From 61598093bbdd283a7edc367d900f223070ead8d2 Mon Sep 17 00:00:00 2001 From: hc <hc@nodka.com> Date: Fri, 10 May 2024 07:43:03 +0000 Subject: [PATCH] add ax88772C AX88772C_eeprom_tools --- kernel/kernel/trace/trace.c | 2549 ++++++++++++++++++++++++++++++++++++++++++---------------- 1 files changed, 1,847 insertions(+), 702 deletions(-) diff --git a/kernel/kernel/trace/trace.c b/kernel/kernel/trace/trace.c index ead2e09..3992a50 100644 --- a/kernel/kernel/trace/trace.c +++ b/kernel/kernel/trace/trace.c @@ -17,6 +17,7 @@ #include <linux/stacktrace.h> #include <linux/writeback.h> #include <linux/kallsyms.h> +#include <linux/security.h> #include <linux/seq_file.h> #include <linux/notifier.h> #include <linux/irqflags.h> @@ -44,6 +45,10 @@ #include <linux/trace.h> #include <linux/sched/clock.h> #include <linux/sched/rt.h> +#include <linux/fsnotify.h> +#include <linux/irq_work.h> +#include <linux/workqueue.h> +#include <trace/hooks/ftrace_dump.h> #include "trace.h" #include "trace_output.h" @@ -64,9 +69,20 @@ static bool __read_mostly tracing_selftest_running; /* - * If a tracer is running, we do not want to run SELFTEST. + * If boot-time tracing including tracers/events via kernel cmdline + * is running, we do not want to run SELFTEST. */ bool __read_mostly tracing_selftest_disabled; + +#ifdef CONFIG_FTRACE_STARTUP_TEST +void __init disable_tracing_selftest(const char *reason) +{ + if (!tracing_selftest_disabled) { + tracing_selftest_disabled = true; + pr_info("Ftrace startup test is disabled due to %s\n", reason); + } +} +#endif /* Pipe tracepoints to printk */ struct trace_iterator *tracepoint_print_iter; @@ -158,7 +174,10 @@ static union trace_eval_map_item *trace_eval_maps; #endif /* CONFIG_TRACE_EVAL_MAP_FILE */ -static int tracing_set_tracer(struct trace_array *tr, const char *buf); +int tracing_set_tracer(struct trace_array *tr, const char *buf); +static void ftrace_trace_userstack(struct trace_array *tr, + struct trace_buffer *buffer, + unsigned long flags, int pc); #define MAX_TRACER_SIZE 100 static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; @@ -215,7 +234,7 @@ static int __init set_trace_boot_options(char *str) { strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); - return 0; + return 1; } __setup("trace_options=", set_trace_boot_options); @@ -226,7 +245,7 @@ { strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE); trace_boot_clock = trace_boot_clock_buf; - return 0; + return 1; } __setup("trace_clock=", set_trace_boot_clock); @@ -248,6 +267,145 @@ do_div(nsec, 1000); return nsec; } + +static void +trace_process_export(struct trace_export *export, + struct ring_buffer_event *event, int flag) +{ + struct trace_entry *entry; + unsigned int size = 0; + + if (export->flags & flag) { + entry = ring_buffer_event_data(event); + size = ring_buffer_event_length(event); + export->write(export, entry, size); + } +} + +static DEFINE_MUTEX(ftrace_export_lock); + +static struct trace_export __rcu *ftrace_exports_list __read_mostly; + +static DEFINE_STATIC_KEY_FALSE(trace_function_exports_enabled); +static DEFINE_STATIC_KEY_FALSE(trace_event_exports_enabled); +static DEFINE_STATIC_KEY_FALSE(trace_marker_exports_enabled); + +static inline void ftrace_exports_enable(struct trace_export *export) +{ + if (export->flags & TRACE_EXPORT_FUNCTION) + static_branch_inc(&trace_function_exports_enabled); + + if (export->flags & TRACE_EXPORT_EVENT) + static_branch_inc(&trace_event_exports_enabled); + + if (export->flags & TRACE_EXPORT_MARKER) + static_branch_inc(&trace_marker_exports_enabled); +} + +static inline void ftrace_exports_disable(struct trace_export *export) +{ + if (export->flags & TRACE_EXPORT_FUNCTION) + static_branch_dec(&trace_function_exports_enabled); + + if (export->flags & TRACE_EXPORT_EVENT) + static_branch_dec(&trace_event_exports_enabled); + + if (export->flags & TRACE_EXPORT_MARKER) + static_branch_dec(&trace_marker_exports_enabled); +} + +static void ftrace_exports(struct ring_buffer_event *event, int flag) +{ + struct trace_export *export; + + preempt_disable_notrace(); + + export = rcu_dereference_raw_check(ftrace_exports_list); + while (export) { + trace_process_export(export, event, flag); + export = rcu_dereference_raw_check(export->next); + } + + preempt_enable_notrace(); +} + +static inline void +add_trace_export(struct trace_export **list, struct trace_export *export) +{ + rcu_assign_pointer(export->next, *list); + /* + * We are entering export into the list but another + * CPU might be walking that list. We need to make sure + * the export->next pointer is valid before another CPU sees + * the export pointer included into the list. + */ + rcu_assign_pointer(*list, export); +} + +static inline int +rm_trace_export(struct trace_export **list, struct trace_export *export) +{ + struct trace_export **p; + + for (p = list; *p != NULL; p = &(*p)->next) + if (*p == export) + break; + + if (*p != export) + return -1; + + rcu_assign_pointer(*p, (*p)->next); + + return 0; +} + +static inline void +add_ftrace_export(struct trace_export **list, struct trace_export *export) +{ + ftrace_exports_enable(export); + + add_trace_export(list, export); +} + +static inline int +rm_ftrace_export(struct trace_export **list, struct trace_export *export) +{ + int ret; + + ret = rm_trace_export(list, export); + ftrace_exports_disable(export); + + return ret; +} + +int register_ftrace_export(struct trace_export *export) +{ + if (WARN_ON_ONCE(!export->write)) + return -1; + + mutex_lock(&ftrace_export_lock); + + add_ftrace_export(&ftrace_exports_list, export); + + mutex_unlock(&ftrace_export_lock); + + return 0; +} +EXPORT_SYMBOL_GPL(register_ftrace_export); + +int unregister_ftrace_export(struct trace_export *export) +{ + int ret; + + mutex_lock(&ftrace_export_lock); + + ret = rm_ftrace_export(&ftrace_exports_list, export); + + mutex_unlock(&ftrace_export_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(unregister_ftrace_export); /* trace_flags holds trace_options default values */ #define TRACE_DEFAULT_FLAGS \ @@ -299,15 +457,44 @@ this_tr->ref--; } +/** + * trace_array_put - Decrement the reference counter for this trace array. + * + * NOTE: Use this when we no longer need the trace array returned by + * trace_array_get_by_name(). This ensures the trace array can be later + * destroyed. + * + */ void trace_array_put(struct trace_array *this_tr) { + if (!this_tr) + return; + mutex_lock(&trace_types_lock); __trace_array_put(this_tr); mutex_unlock(&trace_types_lock); } +EXPORT_SYMBOL_GPL(trace_array_put); + +int tracing_check_open_get_tr(struct trace_array *tr) +{ + int ret; + + ret = security_locked_down(LOCKDOWN_TRACEFS); + if (ret) + return ret; + + if (tracing_disabled) + return -ENODEV; + + if (tr && trace_array_get(tr) < 0) + return -ENODEV; + + return 0; +} int call_filter_check_discard(struct trace_event_call *call, void *rec, - struct ring_buffer *buffer, + struct trace_buffer *buffer, struct ring_buffer_event *event) { if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) && @@ -355,20 +542,26 @@ * Returns false if @task should be traced. */ bool -trace_ignore_this_task(struct trace_pid_list *filtered_pids, struct task_struct *task) +trace_ignore_this_task(struct trace_pid_list *filtered_pids, + struct trace_pid_list *filtered_no_pids, + struct task_struct *task) { /* - * Return false, because if filtered_pids does not exist, - * all pids are good to trace. + * If filterd_no_pids is not empty, and the task's pid is listed + * in filtered_no_pids, then return true. + * Otherwise, if filtered_pids is empty, that means we can + * trace all tasks. If it has content, then only trace pids + * within filtered_pids. */ - if (!filtered_pids) - return false; - return !trace_find_filtered_pid(filtered_pids, task->pid); + return (filtered_pids && + !trace_find_filtered_pid(filtered_pids, task->pid)) || + (filtered_no_pids && + trace_find_filtered_pid(filtered_no_pids, task->pid)); } /** - * trace_pid_filter_add_remove_task - Add or remove a task from a pid_list + * trace_filter_add_remove_task - Add or remove a task from a pid_list * @pid_list: The list to modify * @self: The current task for fork or NULL for exit * @task: The task to add or remove @@ -572,7 +765,7 @@ return read; } -static u64 buffer_ftrace_now(struct trace_buffer *buf, int cpu) +static u64 buffer_ftrace_now(struct array_buffer *buf, int cpu) { u64 ts; @@ -588,7 +781,7 @@ u64 ftrace_now(int cpu) { - return buffer_ftrace_now(&global_trace.trace_buffer, cpu); + return buffer_ftrace_now(&global_trace.array_buffer, cpu); } /** @@ -716,22 +909,22 @@ #endif #ifdef CONFIG_STACKTRACE -static void __ftrace_trace_stack(struct ring_buffer *buffer, +static void __ftrace_trace_stack(struct trace_buffer *buffer, unsigned long flags, int skip, int pc, struct pt_regs *regs); static inline void ftrace_trace_stack(struct trace_array *tr, - struct ring_buffer *buffer, + struct trace_buffer *buffer, unsigned long flags, int skip, int pc, struct pt_regs *regs); #else -static inline void __ftrace_trace_stack(struct ring_buffer *buffer, +static inline void __ftrace_trace_stack(struct trace_buffer *buffer, unsigned long flags, int skip, int pc, struct pt_regs *regs) { } static inline void ftrace_trace_stack(struct trace_array *tr, - struct ring_buffer *buffer, + struct trace_buffer *buffer, unsigned long flags, int skip, int pc, struct pt_regs *regs) { @@ -745,12 +938,11 @@ { struct trace_entry *ent = ring_buffer_event_data(event); - tracing_generic_entry_update(ent, flags, pc); - ent->type = type; + tracing_generic_entry_update(ent, type, flags, pc); } static __always_inline struct ring_buffer_event * -__trace_buffer_lock_reserve(struct ring_buffer *buffer, +__trace_buffer_lock_reserve(struct trace_buffer *buffer, int type, unsigned long len, unsigned long flags, int pc) @@ -766,8 +958,8 @@ void tracer_tracing_on(struct trace_array *tr) { - if (tr->trace_buffer.buffer) - ring_buffer_record_on(tr->trace_buffer.buffer); + if (tr->array_buffer.buffer) + ring_buffer_record_on(tr->array_buffer.buffer); /* * This flag is looked at when buffers haven't been allocated * yet, or by some tracers (like irqsoff), that just want to @@ -795,7 +987,7 @@ static __always_inline void -__buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) +__buffer_unlock_commit(struct trace_buffer *buffer, struct ring_buffer_event *event) { __this_cpu_write(trace_taskinfo_save, true); @@ -818,7 +1010,7 @@ int __trace_puts(unsigned long ip, const char *str, int size) { struct ring_buffer_event *event; - struct ring_buffer *buffer; + struct trace_buffer *buffer; struct print_entry *entry; unsigned long irq_flags; int alloc; @@ -835,11 +1027,14 @@ alloc = sizeof(*entry) + size + 2; /* possible \n added */ local_save_flags(irq_flags); - buffer = global_trace.trace_buffer.buffer; + buffer = global_trace.array_buffer.buffer; + ring_buffer_nest_start(buffer); event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, irq_flags, pc); - if (!event) - return 0; + if (!event) { + size = 0; + goto out; + } entry = ring_buffer_event_data(event); entry->ip = ip; @@ -855,7 +1050,8 @@ __buffer_unlock_commit(buffer, event); ftrace_trace_stack(&global_trace, buffer, irq_flags, 4, pc, NULL); - + out: + ring_buffer_nest_end(buffer); return size; } EXPORT_SYMBOL_GPL(__trace_puts); @@ -868,10 +1064,11 @@ int __trace_bputs(unsigned long ip, const char *str) { struct ring_buffer_event *event; - struct ring_buffer *buffer; + struct trace_buffer *buffer; struct bputs_entry *entry; unsigned long irq_flags; int size = sizeof(struct bputs_entry); + int ret = 0; int pc; if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) @@ -883,11 +1080,13 @@ return 0; local_save_flags(irq_flags); - buffer = global_trace.trace_buffer.buffer; + buffer = global_trace.array_buffer.buffer; + + ring_buffer_nest_start(buffer); event = __trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, irq_flags, pc); if (!event) - return 0; + goto out; entry = ring_buffer_event_data(event); entry->ip = ip; @@ -896,12 +1095,16 @@ __buffer_unlock_commit(buffer, event); ftrace_trace_stack(&global_trace, buffer, irq_flags, 4, pc, NULL); - return 1; + ret = 1; + out: + ring_buffer_nest_end(buffer); + return ret; } EXPORT_SYMBOL_GPL(__trace_bputs); #ifdef CONFIG_TRACER_SNAPSHOT -void tracing_snapshot_instance(struct trace_array *tr) +static void tracing_snapshot_instance_cond(struct trace_array *tr, + void *cond_data) { struct tracer *tracer = tr->current_trace; unsigned long flags; @@ -927,8 +1130,13 @@ } local_irq_save(flags); - update_max_tr(tr, current, smp_processor_id()); + update_max_tr(tr, current, smp_processor_id(), cond_data); local_irq_restore(flags); +} + +void tracing_snapshot_instance(struct trace_array *tr) +{ + tracing_snapshot_instance_cond(tr, NULL); } /** @@ -953,9 +1161,59 @@ } EXPORT_SYMBOL_GPL(tracing_snapshot); -static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, - struct trace_buffer *size_buf, int cpu_id); -static void set_buffer_entries(struct trace_buffer *buf, unsigned long val); +/** + * tracing_snapshot_cond - conditionally take a snapshot of the current buffer. + * @tr: The tracing instance to snapshot + * @cond_data: The data to be tested conditionally, and possibly saved + * + * This is the same as tracing_snapshot() except that the snapshot is + * conditional - the snapshot will only happen if the + * cond_snapshot.update() implementation receiving the cond_data + * returns true, which means that the trace array's cond_snapshot + * update() operation used the cond_data to determine whether the + * snapshot should be taken, and if it was, presumably saved it along + * with the snapshot. + */ +void tracing_snapshot_cond(struct trace_array *tr, void *cond_data) +{ + tracing_snapshot_instance_cond(tr, cond_data); +} +EXPORT_SYMBOL_GPL(tracing_snapshot_cond); + +/** + * tracing_snapshot_cond_data - get the user data associated with a snapshot + * @tr: The tracing instance + * + * When the user enables a conditional snapshot using + * tracing_snapshot_cond_enable(), the user-defined cond_data is saved + * with the snapshot. This accessor is used to retrieve it. + * + * Should not be called from cond_snapshot.update(), since it takes + * the tr->max_lock lock, which the code calling + * cond_snapshot.update() has already done. + * + * Returns the cond_data associated with the trace array's snapshot. + */ +void *tracing_cond_snapshot_data(struct trace_array *tr) +{ + void *cond_data = NULL; + + local_irq_disable(); + arch_spin_lock(&tr->max_lock); + + if (tr->cond_snapshot) + cond_data = tr->cond_snapshot->cond_data; + + arch_spin_unlock(&tr->max_lock); + local_irq_enable(); + + return cond_data; +} +EXPORT_SYMBOL_GPL(tracing_cond_snapshot_data); + +static int resize_buffer_duplicate_size(struct array_buffer *trace_buf, + struct array_buffer *size_buf, int cpu_id); +static void set_buffer_entries(struct array_buffer *buf, unsigned long val); int tracing_alloc_snapshot_instance(struct trace_array *tr) { @@ -965,7 +1223,7 @@ /* allocate spare buffer */ ret = resize_buffer_duplicate_size(&tr->max_buffer, - &tr->trace_buffer, RING_BUFFER_ALL_CPUS); + &tr->array_buffer, RING_BUFFER_ALL_CPUS); if (ret < 0) return ret; @@ -1032,12 +1290,115 @@ tracing_snapshot(); } EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); + +/** + * tracing_snapshot_cond_enable - enable conditional snapshot for an instance + * @tr: The tracing instance + * @cond_data: User data to associate with the snapshot + * @update: Implementation of the cond_snapshot update function + * + * Check whether the conditional snapshot for the given instance has + * already been enabled, or if the current tracer is already using a + * snapshot; if so, return -EBUSY, else create a cond_snapshot and + * save the cond_data and update function inside. + * + * Returns 0 if successful, error otherwise. + */ +int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, + cond_update_fn_t update) +{ + struct cond_snapshot *cond_snapshot; + int ret = 0; + + cond_snapshot = kzalloc(sizeof(*cond_snapshot), GFP_KERNEL); + if (!cond_snapshot) + return -ENOMEM; + + cond_snapshot->cond_data = cond_data; + cond_snapshot->update = update; + + mutex_lock(&trace_types_lock); + + ret = tracing_alloc_snapshot_instance(tr); + if (ret) + goto fail_unlock; + + if (tr->current_trace->use_max_tr) { + ret = -EBUSY; + goto fail_unlock; + } + + /* + * The cond_snapshot can only change to NULL without the + * trace_types_lock. We don't care if we race with it going + * to NULL, but we want to make sure that it's not set to + * something other than NULL when we get here, which we can + * do safely with only holding the trace_types_lock and not + * having to take the max_lock. + */ + if (tr->cond_snapshot) { + ret = -EBUSY; + goto fail_unlock; + } + + local_irq_disable(); + arch_spin_lock(&tr->max_lock); + tr->cond_snapshot = cond_snapshot; + arch_spin_unlock(&tr->max_lock); + local_irq_enable(); + + mutex_unlock(&trace_types_lock); + + return ret; + + fail_unlock: + mutex_unlock(&trace_types_lock); + kfree(cond_snapshot); + return ret; +} +EXPORT_SYMBOL_GPL(tracing_snapshot_cond_enable); + +/** + * tracing_snapshot_cond_disable - disable conditional snapshot for an instance + * @tr: The tracing instance + * + * Check whether the conditional snapshot for the given instance is + * enabled; if so, free the cond_snapshot associated with it, + * otherwise return -EINVAL. + * + * Returns 0 if successful, error otherwise. + */ +int tracing_snapshot_cond_disable(struct trace_array *tr) +{ + int ret = 0; + + local_irq_disable(); + arch_spin_lock(&tr->max_lock); + + if (!tr->cond_snapshot) + ret = -EINVAL; + else { + kfree(tr->cond_snapshot); + tr->cond_snapshot = NULL; + } + + arch_spin_unlock(&tr->max_lock); + local_irq_enable(); + + return ret; +} +EXPORT_SYMBOL_GPL(tracing_snapshot_cond_disable); #else void tracing_snapshot(void) { WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); } EXPORT_SYMBOL_GPL(tracing_snapshot); +void tracing_snapshot_cond(struct trace_array *tr, void *cond_data) +{ + WARN_ONCE(1, "Snapshot feature not enabled, but internal conditional snapshot used"); +} +EXPORT_SYMBOL_GPL(tracing_snapshot_cond); int tracing_alloc_snapshot(void) { WARN_ONCE(1, "Snapshot feature not enabled, but snapshot allocation used"); @@ -1050,12 +1411,27 @@ tracing_snapshot(); } EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); +void *tracing_cond_snapshot_data(struct trace_array *tr) +{ + return NULL; +} +EXPORT_SYMBOL_GPL(tracing_cond_snapshot_data); +int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update) +{ + return -ENODEV; +} +EXPORT_SYMBOL_GPL(tracing_snapshot_cond_enable); +int tracing_snapshot_cond_disable(struct trace_array *tr) +{ + return false; +} +EXPORT_SYMBOL_GPL(tracing_snapshot_cond_disable); #endif /* CONFIG_TRACER_SNAPSHOT */ void tracer_tracing_off(struct trace_array *tr) { - if (tr->trace_buffer.buffer) - ring_buffer_record_off(tr->trace_buffer.buffer); + if (tr->array_buffer.buffer) + ring_buffer_record_off(tr->array_buffer.buffer); /* * This flag is looked at when buffers haven't been allocated * yet, or by some tracers (like irqsoff), that just want to @@ -1085,8 +1461,11 @@ void disable_trace_on_warning(void) { - if (__disable_trace_on_warning) + if (__disable_trace_on_warning) { + trace_array_printk_buf(global_trace.array_buffer.buffer, _THIS_IP_, + "Disabling tracing due to warning\n"); tracing_off(); + } } /** @@ -1097,8 +1476,8 @@ */ bool tracer_tracing_is_on(struct trace_array *tr) { - if (tr->trace_buffer.buffer) - return ring_buffer_record_is_on(tr->trace_buffer.buffer); + if (tr->array_buffer.buffer) + return ring_buffer_record_is_on(tr->array_buffer.buffer); return !tr->buffer_disabled; } @@ -1118,10 +1497,12 @@ if (!str) return 0; buf_size = memparse(str, &str); - /* nr_entries can not be zero */ - if (buf_size == 0) - return 0; - trace_buf_size = buf_size; + /* + * nr_entries can not be zero and the startup + * tests require some buffer space. Therefore + * ensure we have at least 4096 bytes of buffer. + */ + trace_buf_size = max(4096UL, buf_size); return 1; } __setup("trace_buf_size=", set_buf_size); @@ -1315,6 +1696,73 @@ } unsigned long __read_mostly tracing_thresh; +static const struct file_operations tracing_max_lat_fops; + +#if (defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)) && \ + defined(CONFIG_FSNOTIFY) + +static struct workqueue_struct *fsnotify_wq; + +static void latency_fsnotify_workfn(struct work_struct *work) +{ + struct trace_array *tr = container_of(work, struct trace_array, + fsnotify_work); + fsnotify_inode(tr->d_max_latency->d_inode, FS_MODIFY); +} + +static void latency_fsnotify_workfn_irq(struct irq_work *iwork) +{ + struct trace_array *tr = container_of(iwork, struct trace_array, + fsnotify_irqwork); + queue_work(fsnotify_wq, &tr->fsnotify_work); +} + +static void trace_create_maxlat_file(struct trace_array *tr, + struct dentry *d_tracer) +{ + INIT_WORK(&tr->fsnotify_work, latency_fsnotify_workfn); + init_irq_work(&tr->fsnotify_irqwork, latency_fsnotify_workfn_irq); + tr->d_max_latency = trace_create_file("tracing_max_latency", 0644, + d_tracer, &tr->max_latency, + &tracing_max_lat_fops); +} + +__init static int latency_fsnotify_init(void) +{ + fsnotify_wq = alloc_workqueue("tr_max_lat_wq", + WQ_UNBOUND | WQ_HIGHPRI, 0); + if (!fsnotify_wq) { + pr_err("Unable to allocate tr_max_lat_wq\n"); + return -ENOMEM; + } + return 0; +} + +late_initcall_sync(latency_fsnotify_init); + +void latency_fsnotify(struct trace_array *tr) +{ + if (!fsnotify_wq) + return; + /* + * We cannot call queue_work(&tr->fsnotify_work) from here because it's + * possible that we are called from __schedule() or do_idle(), which + * could cause a deadlock. + */ + irq_work_queue(&tr->fsnotify_irqwork); +} + +/* + * (defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)) && \ + * defined(CONFIG_FSNOTIFY) + */ +#else + +#define trace_create_maxlat_file(tr, d_tracer) \ + trace_create_file("tracing_max_latency", 0644, d_tracer, \ + &tr->max_latency, &tracing_max_lat_fops) + +#endif #ifdef CONFIG_TRACER_MAX_TRACE /* @@ -1325,8 +1773,8 @@ static void __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) { - struct trace_buffer *trace_buf = &tr->trace_buffer; - struct trace_buffer *max_buf = &tr->max_buffer; + struct array_buffer *trace_buf = &tr->array_buffer; + struct array_buffer *max_buf = &tr->max_buffer; struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu); struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu); @@ -1337,7 +1785,7 @@ max_data->critical_start = data->critical_start; max_data->critical_end = data->critical_end; - memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); + strncpy(max_data->comm, tsk->comm, TASK_COMM_LEN); max_data->pid = tsk->pid; /* * If tsk == current, then use current_uid(), as that does not use @@ -1354,6 +1802,7 @@ /* record this tasks comm */ tracing_record_cmdline(tsk); + latency_fsnotify(tr); } /** @@ -1361,12 +1810,14 @@ * @tr: tracer * @tsk: the task with the latency * @cpu: The cpu that initiated the trace. + * @cond_data: User data associated with a conditional snapshot * * Flip the buffers between the @tr and the max_tr and record information * about which task was the cause of this latency. */ void -update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) +update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu, + void *cond_data) { if (tr->stop_count) return; @@ -1381,23 +1832,29 @@ arch_spin_lock(&tr->max_lock); - /* Inherit the recordable setting from trace_buffer */ - if (ring_buffer_record_is_set_on(tr->trace_buffer.buffer)) + /* Inherit the recordable setting from array_buffer */ + if (ring_buffer_record_is_set_on(tr->array_buffer.buffer)) ring_buffer_record_on(tr->max_buffer.buffer); else ring_buffer_record_off(tr->max_buffer.buffer); - swap(tr->trace_buffer.buffer, tr->max_buffer.buffer); +#ifdef CONFIG_TRACER_SNAPSHOT + if (tr->cond_snapshot && !tr->cond_snapshot->update(tr, cond_data)) + goto out_unlock; +#endif + swap(tr->array_buffer.buffer, tr->max_buffer.buffer); __update_max_tr(tr, tsk, cpu); + + out_unlock: arch_spin_unlock(&tr->max_lock); } /** * update_max_tr_single - only copy one trace over, and reset the rest - * @tr - tracer - * @tsk - task with the latency - * @cpu - the cpu of the buffer to copy. + * @tr: tracer + * @tsk: task with the latency + * @cpu: the cpu of the buffer to copy. * * Flip the trace of a single CPU buffer between the @tr and the max_tr. */ @@ -1418,7 +1875,7 @@ arch_spin_lock(&tr->max_lock); - ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu); + ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->array_buffer.buffer, cpu); if (ret == -EBUSY) { /* @@ -1426,9 +1883,10 @@ * place on this CPU. We fail to record, but we reset * the max trace buffer (no one writes directly to it) * and flag that it failed. + * Another reason is resize is in progress. */ trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_, - "Failed to swap buffers due to commit in progress\n"); + "Failed to swap buffers due to commit or resize in progress\n"); } WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); @@ -1438,13 +1896,13 @@ } #endif /* CONFIG_TRACER_MAX_TRACE */ -static int wait_on_pipe(struct trace_iterator *iter, bool full) +static int wait_on_pipe(struct trace_iterator *iter, int full) { /* Iterators are static, they should be filled or empty */ if (trace_buffer_iter(iter, iter->cpu_file)) return 0; - return ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file, + return ring_buffer_wait(iter->array_buffer->buffer, iter->cpu_file, full); } @@ -1495,7 +1953,7 @@ * internal tracing to verify that everything is in order. * If we fail, we do not register this tracer. */ - tracing_reset_online_cpus(&tr->trace_buffer); + tracing_reset_online_cpus(&tr->array_buffer); tr->current_trace = type; @@ -1521,7 +1979,7 @@ return -1; } /* Only reset on passing, to avoid touching corrupted buffers */ - tracing_reset_online_cpus(&tr->trace_buffer); + tracing_reset_online_cpus(&tr->array_buffer); #ifdef CONFIG_TRACER_MAX_TRACE if (type->use_max_tr) { @@ -1555,6 +2013,10 @@ tracing_selftest_running = true; list_for_each_entry_safe(p, n, &postponed_selftests, list) { + /* This loop can take minutes when sanitizers are enabled, so + * lets make sure we allow RCU processing. + */ + cond_resched(); ret = run_tracer_selftest(p->type); /* If the test fails, then warn and remove from available_tracers */ if (ret < 0) { @@ -1593,7 +2055,7 @@ /** * register_tracer - register a tracer with the ftrace system. - * @type - the plugin for the tracer + * @type: the plugin for the tracer * * Register a new plugin tracer. */ @@ -1610,6 +2072,12 @@ if (strlen(type->name) >= MAX_TRACER_SIZE) { pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); return -1; + } + + if (security_locked_down(LOCKDOWN_TRACEFS)) { + pr_warn("Can not register tracer %s due to lockdown\n", + type->name); + return -EPERM; } mutex_lock(&trace_types_lock); @@ -1670,19 +2138,15 @@ apply_trace_boot_options(); /* disable other selftests, since this will break it. */ - tracing_selftest_disabled = true; -#ifdef CONFIG_FTRACE_STARTUP_TEST - printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", - type->name); -#endif + disable_tracing_selftest("running a tracer"); out_unlock: return ret; } -void tracing_reset(struct trace_buffer *buf, int cpu) +static void tracing_reset_cpu(struct array_buffer *buf, int cpu) { - struct ring_buffer *buffer = buf->buffer; + struct trace_buffer *buffer = buf->buffer; if (!buffer) return; @@ -1690,16 +2154,15 @@ ring_buffer_record_disable(buffer); /* Make sure all commits have finished */ - synchronize_sched(); + synchronize_rcu(); ring_buffer_reset_cpu(buffer, cpu); ring_buffer_record_enable(buffer); } -void tracing_reset_online_cpus(struct trace_buffer *buf) +void tracing_reset_online_cpus(struct array_buffer *buf) { - struct ring_buffer *buffer = buf->buffer; - int cpu; + struct trace_buffer *buffer = buf->buffer; if (!buffer) return; @@ -1707,30 +2170,38 @@ ring_buffer_record_disable(buffer); /* Make sure all commits have finished */ - synchronize_sched(); + synchronize_rcu(); buf->time_start = buffer_ftrace_now(buf, buf->cpu); - for_each_online_cpu(cpu) - ring_buffer_reset_cpu(buffer, cpu); + ring_buffer_reset_online_cpus(buffer); ring_buffer_record_enable(buffer); } /* Must have trace_types_lock held */ -void tracing_reset_all_online_cpus(void) +void tracing_reset_all_online_cpus_unlocked(void) { struct trace_array *tr; + + lockdep_assert_held(&trace_types_lock); list_for_each_entry(tr, &ftrace_trace_arrays, list) { if (!tr->clear_trace) continue; tr->clear_trace = false; - tracing_reset_online_cpus(&tr->trace_buffer); + tracing_reset_online_cpus(&tr->array_buffer); #ifdef CONFIG_TRACER_MAX_TRACE tracing_reset_online_cpus(&tr->max_buffer); #endif } +} + +void tracing_reset_all_online_cpus(void) +{ + mutex_lock(&trace_types_lock); + tracing_reset_all_online_cpus_unlocked(); + mutex_unlock(&trace_types_lock); } /* @@ -1744,6 +2215,11 @@ #define SAVED_CMDLINES_DEFAULT 128 #define NO_CMDLINE_MAP UINT_MAX +/* + * Preemption must be disabled before acquiring trace_cmdline_lock. + * The various trace_arrays' max_lock must be acquired in a context + * where interrupt is disabled. + */ static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; struct saved_cmdlines_buffer { unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; @@ -1761,7 +2237,7 @@ static inline void set_cmdline(int idx, const char *cmdline) { - memcpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN); + strncpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN); } static int allocate_cmdlines_buffer(unsigned int val, @@ -1820,7 +2296,7 @@ */ void tracing_start(void) { - struct ring_buffer *buffer; + struct trace_buffer *buffer; unsigned long flags; if (tracing_disabled) @@ -1839,7 +2315,7 @@ /* Prevent the buffers from switching */ arch_spin_lock(&global_trace.max_lock); - buffer = global_trace.trace_buffer.buffer; + buffer = global_trace.array_buffer.buffer; if (buffer) ring_buffer_record_enable(buffer); @@ -1857,7 +2333,7 @@ static void tracing_start_tr(struct trace_array *tr) { - struct ring_buffer *buffer; + struct trace_buffer *buffer; unsigned long flags; if (tracing_disabled) @@ -1878,7 +2354,7 @@ goto out; } - buffer = tr->trace_buffer.buffer; + buffer = tr->array_buffer.buffer; if (buffer) ring_buffer_record_enable(buffer); @@ -1894,7 +2370,7 @@ */ void tracing_stop(void) { - struct ring_buffer *buffer; + struct trace_buffer *buffer; unsigned long flags; raw_spin_lock_irqsave(&global_trace.start_lock, flags); @@ -1904,7 +2380,7 @@ /* Prevent the buffers from switching */ arch_spin_lock(&global_trace.max_lock); - buffer = global_trace.trace_buffer.buffer; + buffer = global_trace.array_buffer.buffer; if (buffer) ring_buffer_record_disable(buffer); @@ -1922,7 +2398,7 @@ static void tracing_stop_tr(struct trace_array *tr) { - struct ring_buffer *buffer; + struct trace_buffer *buffer; unsigned long flags; /* If global, we need to also stop the max tracer */ @@ -1933,7 +2409,7 @@ if (tr->stop_count++) goto out; - buffer = tr->trace_buffer.buffer; + buffer = tr->array_buffer.buffer; if (buffer) ring_buffer_record_disable(buffer); @@ -1956,7 +2432,11 @@ * the lock, but we also don't want to spin * nor do we want to disable interrupts, * so if we miss here, then better luck next time. + * + * This is called within the scheduler and wake up, so interrupts + * had better been disabled and run queue lock been held. */ + lockdep_assert_preemption_disabled(); if (!arch_spin_trylock(&trace_cmdline_lock)) return 0; @@ -2064,9 +2544,9 @@ /** * tracing_record_taskinfo - record the task info of a task * - * @task - task to record - * @flags - TRACE_RECORD_CMDLINE for recording comm - * - TRACE_RECORD_TGID for recording tgid + * @task: task to record + * @flags: TRACE_RECORD_CMDLINE for recording comm + * TRACE_RECORD_TGID for recording tgid */ void tracing_record_taskinfo(struct task_struct *task, int flags) { @@ -2092,10 +2572,10 @@ /** * tracing_record_taskinfo_sched_switch - record task info for sched_switch * - * @prev - previous task during sched_switch - * @next - next task during sched_switch - * @flags - TRACE_RECORD_CMDLINE for recording comm - * TRACE_RECORD_TGID for recording tgid + * @prev: previous task during sched_switch + * @next: next task during sched_switch + * @flags: TRACE_RECORD_CMDLINE for recording comm + * TRACE_RECORD_TGID for recording tgid */ void tracing_record_taskinfo_sched_switch(struct task_struct *prev, struct task_struct *next, int flags) @@ -2145,14 +2625,14 @@ EXPORT_SYMBOL_GPL(trace_handle_return); void -tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, - int pc) +tracing_generic_entry_update(struct trace_entry *entry, unsigned short type, + unsigned long flags, int pc) { struct task_struct *tsk = current; entry->preempt_count = pc & 0xff; - entry->preempt_lazy_count = preempt_lazy_count(); entry->pid = (tsk) ? tsk->pid : 0; + entry->type = type; entry->flags = #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | @@ -2162,16 +2642,13 @@ ((pc & NMI_MASK ) ? TRACE_FLAG_NMI : 0) | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | ((pc & SOFTIRQ_OFFSET) ? TRACE_FLAG_SOFTIRQ : 0) | - (tif_need_resched_now() ? TRACE_FLAG_NEED_RESCHED : 0) | - (need_resched_lazy() ? TRACE_FLAG_NEED_RESCHED_LAZY : 0) | + (tif_need_resched() ? TRACE_FLAG_NEED_RESCHED : 0) | (test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0); - - entry->migrate_disable = (tsk) ? __migrate_disabled(tsk) & 0xFF : 0; } EXPORT_SYMBOL_GPL(tracing_generic_entry_update); struct ring_buffer_event * -trace_buffer_lock_reserve(struct ring_buffer *buffer, +trace_buffer_lock_reserve(struct trace_buffer *buffer, int type, unsigned long len, unsigned long flags, int pc) @@ -2221,7 +2698,7 @@ preempt_disable(); if (cpu == smp_processor_id() && - this_cpu_read(trace_buffered_event) != + __this_cpu_read(trace_buffered_event) != per_cpu(trace_buffered_event, cpu)) WARN_ON_ONCE(1); preempt_enable(); @@ -2271,7 +2748,7 @@ preempt_enable(); /* Wait for all current users to finish */ - synchronize_sched(); + synchronize_rcu(); for_each_tracing_cpu(cpu) { free_page((unsigned long)per_cpu(trace_buffered_event, cpu)); @@ -2290,10 +2767,10 @@ preempt_enable(); } -static struct ring_buffer *temp_buffer; +static struct trace_buffer *temp_buffer; struct ring_buffer_event * -trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, +trace_event_buffer_lock_reserve(struct trace_buffer **current_rb, struct trace_event_file *trace_file, int type, unsigned long len, unsigned long flags, int pc) @@ -2301,7 +2778,7 @@ struct ring_buffer_event *entry; int val; - *current_rb = trace_file->tr->trace_buffer.buffer; + *current_rb = trace_file->tr->array_buffer.buffer; if (!ring_buffer_time_stamp_abs(*current_rb) && (trace_file->flags & (EVENT_FILE_FL_SOFT_DISABLED | EVENT_FILE_FL_FILTERED)) && @@ -2321,7 +2798,7 @@ /* * If tracing is off, but we have triggers enabled * we still need to look at the event data. Use the temp_buffer - * to store the trace event for the tigger to use. It's recusive + * to store the trace event for the trigger to use. It's recursive * safe and will not be recorded anywhere. */ if (!entry && trace_file->flags & EVENT_FILE_FL_TRIGGER_COND) { @@ -2333,12 +2810,13 @@ } EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); -static DEFINE_SPINLOCK(tracepoint_iter_lock); +static DEFINE_RAW_SPINLOCK(tracepoint_iter_lock); static DEFINE_MUTEX(tracepoint_printk_mutex); static void output_printk(struct trace_event_buffer *fbuffer) { struct trace_event_call *event_call; + struct trace_event_file *file; struct trace_event *event; unsigned long flags; struct trace_iterator *iter = tracepoint_print_iter; @@ -2352,20 +2830,26 @@ !event_call->event.funcs->trace) return; + file = fbuffer->trace_file; + if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) || + (unlikely(file->flags & EVENT_FILE_FL_FILTERED) && + !filter_match_preds(file->filter, fbuffer->entry))) + return; + event = &fbuffer->trace_file->event_call->event; - spin_lock_irqsave(&tracepoint_iter_lock, flags); + raw_spin_lock_irqsave(&tracepoint_iter_lock, flags); trace_seq_init(&iter->seq); iter->ent = fbuffer->entry; event_call->event.funcs->trace(iter, 0, event); trace_seq_putc(&iter->seq, 0); printk("%s", iter->seq.buffer); - spin_unlock_irqrestore(&tracepoint_iter_lock, flags); + raw_spin_unlock_irqrestore(&tracepoint_iter_lock, flags); } int tracepoint_printk_sysctl(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, + void *buffer, size_t *lenp, loff_t *ppos) { int save_tracepoint_printk; @@ -2402,9 +2886,11 @@ if (static_key_false(&tracepoint_printk_key.key)) output_printk(fbuffer); - event_trigger_unlock_commit(fbuffer->trace_file, fbuffer->buffer, + if (static_branch_unlikely(&trace_event_exports_enabled)) + ftrace_exports(fbuffer->event, TRACE_EXPORT_EVENT); + event_trigger_unlock_commit_regs(fbuffer->trace_file, fbuffer->buffer, fbuffer->event, fbuffer->entry, - fbuffer->flags, fbuffer->pc); + fbuffer->flags, fbuffer->pc, fbuffer->regs); } EXPORT_SYMBOL_GPL(trace_event_buffer_commit); @@ -2418,7 +2904,7 @@ # define STACK_SKIP 3 void trace_buffer_unlock_commit_regs(struct trace_array *tr, - struct ring_buffer *buffer, + struct trace_buffer *buffer, struct ring_buffer_event *event, unsigned long flags, int pc, struct pt_regs *regs) @@ -2439,134 +2925,11 @@ * Similar to trace_buffer_unlock_commit_regs() but do not dump stack. */ void -trace_buffer_unlock_commit_nostack(struct ring_buffer *buffer, +trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer, struct ring_buffer_event *event) { __buffer_unlock_commit(buffer, event); } - -static void -trace_process_export(struct trace_export *export, - struct ring_buffer_event *event) -{ - struct trace_entry *entry; - unsigned int size = 0; - - entry = ring_buffer_event_data(event); - size = ring_buffer_event_length(event); - export->write(export, entry, size); -} - -static DEFINE_MUTEX(ftrace_export_lock); - -static struct trace_export __rcu *ftrace_exports_list __read_mostly; - -static DEFINE_STATIC_KEY_FALSE(ftrace_exports_enabled); - -static inline void ftrace_exports_enable(void) -{ - static_branch_enable(&ftrace_exports_enabled); -} - -static inline void ftrace_exports_disable(void) -{ - static_branch_disable(&ftrace_exports_enabled); -} - -void ftrace_exports(struct ring_buffer_event *event) -{ - struct trace_export *export; - - preempt_disable_notrace(); - - export = rcu_dereference_raw_notrace(ftrace_exports_list); - while (export) { - trace_process_export(export, event); - export = rcu_dereference_raw_notrace(export->next); - } - - preempt_enable_notrace(); -} - -static inline void -add_trace_export(struct trace_export **list, struct trace_export *export) -{ - rcu_assign_pointer(export->next, *list); - /* - * We are entering export into the list but another - * CPU might be walking that list. We need to make sure - * the export->next pointer is valid before another CPU sees - * the export pointer included into the list. - */ - rcu_assign_pointer(*list, export); -} - -static inline int -rm_trace_export(struct trace_export **list, struct trace_export *export) -{ - struct trace_export **p; - - for (p = list; *p != NULL; p = &(*p)->next) - if (*p == export) - break; - - if (*p != export) - return -1; - - rcu_assign_pointer(*p, (*p)->next); - - return 0; -} - -static inline void -add_ftrace_export(struct trace_export **list, struct trace_export *export) -{ - if (*list == NULL) - ftrace_exports_enable(); - - add_trace_export(list, export); -} - -static inline int -rm_ftrace_export(struct trace_export **list, struct trace_export *export) -{ - int ret; - - ret = rm_trace_export(list, export); - if (*list == NULL) - ftrace_exports_disable(); - - return ret; -} - -int register_ftrace_export(struct trace_export *export) -{ - if (WARN_ON_ONCE(!export->write)) - return -1; - - mutex_lock(&ftrace_export_lock); - - add_ftrace_export(&ftrace_exports_list, export); - - mutex_unlock(&ftrace_export_lock); - - return 0; -} -EXPORT_SYMBOL_GPL(register_ftrace_export); - -int unregister_ftrace_export(struct trace_export *export) -{ - int ret; - - mutex_lock(&ftrace_export_lock); - - ret = rm_ftrace_export(&ftrace_exports_list, export); - - mutex_unlock(&ftrace_export_lock); - - return ret; -} -EXPORT_SYMBOL_GPL(unregister_ftrace_export); void trace_function(struct trace_array *tr, @@ -2574,7 +2937,7 @@ int pc) { struct trace_event_call *call = &event_function; - struct ring_buffer *buffer = tr->trace_buffer.buffer; + struct trace_buffer *buffer = tr->array_buffer.buffer; struct ring_buffer_event *event; struct ftrace_entry *entry; @@ -2587,35 +2950,41 @@ entry->parent_ip = parent_ip; if (!call_filter_check_discard(call, entry, buffer, event)) { - if (static_branch_unlikely(&ftrace_exports_enabled)) - ftrace_exports(event); + if (static_branch_unlikely(&trace_function_exports_enabled)) + ftrace_exports(event, TRACE_EXPORT_FUNCTION); __buffer_unlock_commit(buffer, event); } } #ifdef CONFIG_STACKTRACE -#define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) +/* Allow 4 levels of nesting: normal, softirq, irq, NMI */ +#define FTRACE_KSTACK_NESTING 4 + +#define FTRACE_KSTACK_ENTRIES (PAGE_SIZE / FTRACE_KSTACK_NESTING) + struct ftrace_stack { - unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; + unsigned long calls[FTRACE_KSTACK_ENTRIES]; }; -static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); + +struct ftrace_stacks { + struct ftrace_stack stacks[FTRACE_KSTACK_NESTING]; +}; + +static DEFINE_PER_CPU(struct ftrace_stacks, ftrace_stacks); static DEFINE_PER_CPU(int, ftrace_stack_reserve); -static void __ftrace_trace_stack(struct ring_buffer *buffer, +static void __ftrace_trace_stack(struct trace_buffer *buffer, unsigned long flags, int skip, int pc, struct pt_regs *regs) { struct trace_event_call *call = &event_kernel_stack; struct ring_buffer_event *event; + unsigned int size, nr_entries; + struct ftrace_stack *fstack; struct stack_entry *entry; - struct stack_trace trace; - int use_stack; - int size = FTRACE_STACK_ENTRIES; - - trace.nr_entries = 0; - trace.skip = skip; + int stackidx; /* * Add one, for this function and the call to save_stack_trace() @@ -2623,43 +2992,37 @@ */ #ifndef CONFIG_UNWINDER_ORC if (!regs) - trace.skip++; + skip++; #endif - /* - * Since events can happen in NMIs there's no safe way to - * use the per cpu ftrace_stacks. We reserve it and if an interrupt - * or NMI comes in, it will just have to use the default - * FTRACE_STACK_SIZE. - */ preempt_disable_notrace(); - use_stack = __this_cpu_inc_return(ftrace_stack_reserve); + stackidx = __this_cpu_inc_return(ftrace_stack_reserve) - 1; + + /* This should never happen. If it does, yell once and skip */ + if (WARN_ON_ONCE(stackidx >= FTRACE_KSTACK_NESTING)) + goto out; + /* - * We don't need any atomic variables, just a barrier. - * If an interrupt comes in, we don't care, because it would - * have exited and put the counter back to what we want. - * We just need a barrier to keep gcc from moving things - * around. + * The above __this_cpu_inc_return() is 'atomic' cpu local. An + * interrupt will either see the value pre increment or post + * increment. If the interrupt happens pre increment it will have + * restored the counter when it returns. We just need a barrier to + * keep gcc from moving things around. */ barrier(); - if (use_stack == 1) { - trace.entries = this_cpu_ptr(ftrace_stack.calls); - trace.max_entries = FTRACE_STACK_MAX_ENTRIES; - if (regs) - save_stack_trace_regs(regs, &trace); - else - save_stack_trace(&trace); + fstack = this_cpu_ptr(ftrace_stacks.stacks) + stackidx; + size = ARRAY_SIZE(fstack->calls); - if (trace.nr_entries > size) - size = trace.nr_entries; - } else - /* From now on, use_stack is a boolean */ - use_stack = 0; + if (regs) { + nr_entries = stack_trace_save_regs(regs, fstack->calls, + size, skip); + } else { + nr_entries = stack_trace_save(fstack->calls, size, skip); + } - size *= sizeof(unsigned long); - + size = nr_entries * sizeof(unsigned long); event = __trace_buffer_lock_reserve(buffer, TRACE_STACK, (sizeof(*entry) - sizeof(entry->caller)) + size, flags, pc); @@ -2667,21 +3030,8 @@ goto out; entry = ring_buffer_event_data(event); - memset(&entry->caller, 0, size); - - if (use_stack) - memcpy(&entry->caller, trace.entries, - trace.nr_entries * sizeof(unsigned long)); - else { - trace.max_entries = FTRACE_STACK_ENTRIES; - trace.entries = entry->caller; - if (regs) - save_stack_trace_regs(regs, &trace); - else - save_stack_trace(&trace); - } - - entry->size = trace.nr_entries; + memcpy(&entry->caller, fstack->calls, size); + entry->size = nr_entries; if (!call_filter_check_discard(call, entry, buffer, event)) __buffer_unlock_commit(buffer, event); @@ -2695,7 +3045,7 @@ } static inline void ftrace_trace_stack(struct trace_array *tr, - struct ring_buffer *buffer, + struct trace_buffer *buffer, unsigned long flags, int skip, int pc, struct pt_regs *regs) { @@ -2708,7 +3058,7 @@ void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, int pc) { - struct ring_buffer *buffer = tr->trace_buffer.buffer; + struct trace_buffer *buffer = tr->array_buffer.buffer; if (rcu_is_watching()) { __ftrace_trace_stack(buffer, flags, skip, pc, NULL); @@ -2746,20 +3096,21 @@ /* Skip 1 to skip this function. */ skip++; #endif - __ftrace_trace_stack(global_trace.trace_buffer.buffer, + __ftrace_trace_stack(global_trace.array_buffer.buffer, flags, skip, preempt_count(), NULL); } +EXPORT_SYMBOL_GPL(trace_dump_stack); +#ifdef CONFIG_USER_STACKTRACE_SUPPORT static DEFINE_PER_CPU(int, user_stack_count); -void +static void ftrace_trace_userstack(struct trace_array *tr, - struct ring_buffer *buffer, unsigned long flags, int pc) + struct trace_buffer *buffer, unsigned long flags, int pc) { struct trace_event_call *call = &event_user_stack; struct ring_buffer_event *event; struct userstack_entry *entry; - struct stack_trace trace; if (!(tr->trace_flags & TRACE_ITER_USERSTACKTRACE)) return; @@ -2790,12 +3141,7 @@ entry->tgid = current->tgid; memset(&entry->caller, 0, sizeof(entry->caller)); - trace.nr_entries = 0; - trace.max_entries = FTRACE_STACK_ENTRIES; - trace.skip = 0; - trace.entries = entry->caller; - - save_stack_trace_user(&trace); + stack_trace_save_user(entry->caller, FTRACE_STACK_ENTRIES); if (!call_filter_check_discard(call, entry, buffer, event)) __buffer_unlock_commit(buffer, event); @@ -2804,13 +3150,13 @@ out: preempt_enable(); } - -#ifdef UNUSED -static void __trace_userstack(struct trace_array *tr, unsigned long flags) +#else /* CONFIG_USER_STACKTRACE_SUPPORT */ +static void ftrace_trace_userstack(struct trace_array *tr, + struct trace_buffer *buffer, + unsigned long flags, int pc) { - ftrace_trace_userstack(tr, flags, preempt_count()); } -#endif /* UNUSED */ +#endif /* !CONFIG_USER_STACKTRACE_SUPPORT */ #endif /* CONFIG_STACKTRACE */ @@ -2851,8 +3197,11 @@ { struct trace_buffer_struct __percpu *buffers; + if (trace_percpu_buffer) + return 0; + buffers = alloc_percpu(struct trace_buffer_struct); - if (WARN(!buffers, "Could not allocate percpu trace_printk buffer")) + if (MEM_FAIL(!buffers, "Could not allocate percpu trace_printk buffer")) return -ENOMEM; trace_percpu_buffer = buffers; @@ -2897,9 +3246,10 @@ * directly here. If the global_trace.buffer is already * allocated here, then this was called by module code. */ - if (global_trace.trace_buffer.buffer) + if (global_trace.array_buffer.buffer) tracing_start_cmdline_record(); } +EXPORT_SYMBOL_GPL(trace_printk_init_buffers); void trace_printk_start_comm(void) { @@ -2922,13 +3272,15 @@ /** * trace_vbprintk - write binary msg to tracing buffer - * + * @ip: The address of the caller + * @fmt: The string format to write to the buffer + * @args: Arguments for @fmt */ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) { struct trace_event_call *call = &event_bprint; struct ring_buffer_event *event; - struct ring_buffer *buffer; + struct trace_buffer *buffer; struct trace_array *tr = &global_trace; struct bprint_entry *entry; unsigned long flags; @@ -2953,11 +3305,12 @@ len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) - goto out; + goto out_put; local_save_flags(flags); size = sizeof(*entry) + sizeof(u32) * len; - buffer = tr->trace_buffer.buffer; + buffer = tr->array_buffer.buffer; + ring_buffer_nest_start(buffer); event = __trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, flags, pc); if (!event) @@ -2973,6 +3326,8 @@ } out: + ring_buffer_nest_end(buffer); +out_put: put_trace_buf(); out_nobuffer: @@ -2985,7 +3340,7 @@ __printf(3, 0) static int -__trace_array_vprintk(struct ring_buffer *buffer, +__trace_array_vprintk(struct trace_buffer *buffer, unsigned long ip, const char *fmt, va_list args) { struct trace_event_call *call = &event_print; @@ -3015,6 +3370,7 @@ local_save_flags(flags); size = sizeof(*entry) + len + 1; + ring_buffer_nest_start(buffer); event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, flags, pc); if (!event) @@ -3029,6 +3385,7 @@ } out: + ring_buffer_nest_end(buffer); put_trace_buf(); out_nobuffer: @@ -3042,9 +3399,29 @@ int trace_array_vprintk(struct trace_array *tr, unsigned long ip, const char *fmt, va_list args) { - return __trace_array_vprintk(tr->trace_buffer.buffer, ip, fmt, args); + return __trace_array_vprintk(tr->array_buffer.buffer, ip, fmt, args); } +/** + * trace_array_printk - Print a message to a specific instance + * @tr: The instance trace_array descriptor + * @ip: The instruction pointer that this is called from. + * @fmt: The format to print (printf format) + * + * If a subsystem sets up its own instance, they have the right to + * printk strings into their tracing instance buffer using this + * function. Note, this function will not write into the top level + * buffer (use trace_printk() for that), as writing into the top level + * buffer should only have events that can be individually disabled. + * trace_printk() is only used for debugging a kernel, and should not + * be ever encorporated in normal use. + * + * trace_array_printk() can be used, as it will not add noise to the + * top level tracing buffer. + * + * Note, trace_array_init_printk() must be called on @tr before this + * can be used. + */ __printf(3, 0) int trace_array_printk(struct trace_array *tr, unsigned long ip, const char *fmt, ...) @@ -3052,20 +3429,46 @@ int ret; va_list ap; - if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) - return 0; - if (!tr) return -ENOENT; + + /* This is only allowed for created instances */ + if (tr == &global_trace) + return 0; + + if (!(tr->trace_flags & TRACE_ITER_PRINTK)) + return 0; va_start(ap, fmt); ret = trace_array_vprintk(tr, ip, fmt, ap); va_end(ap); return ret; } +EXPORT_SYMBOL_GPL(trace_array_printk); + +/** + * trace_array_init_printk - Initialize buffers for trace_array_printk() + * @tr: The trace array to initialize the buffers for + * + * As trace_array_printk() only writes into instances, they are OK to + * have in the kernel (unlike trace_printk()). This needs to be called + * before trace_array_printk() can be used on a trace_array. + */ +int trace_array_init_printk(struct trace_array *tr) +{ + if (!tr) + return -ENOENT; + + /* This is only allowed for created instances */ + if (tr == &global_trace) + return -EINVAL; + + return alloc_percpu_trace_buffer(); +} +EXPORT_SYMBOL_GPL(trace_array_init_printk); __printf(3, 4) -int trace_array_printk_buf(struct ring_buffer *buffer, +int trace_array_printk_buf(struct trace_buffer *buffer, unsigned long ip, const char *fmt, ...) { int ret; @@ -3093,7 +3496,7 @@ iter->idx++; if (buf_iter) - ring_buffer_read(buf_iter, NULL); + ring_buffer_iter_advance(buf_iter); } static struct trace_entry * @@ -3103,11 +3506,15 @@ struct ring_buffer_event *event; struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); - if (buf_iter) + if (buf_iter) { event = ring_buffer_iter_peek(buf_iter, ts); - else - event = ring_buffer_peek(iter->trace_buffer->buffer, cpu, ts, + if (lost_events) + *lost_events = ring_buffer_iter_dropped(buf_iter) ? + (unsigned long)-1 : 0; + } else { + event = ring_buffer_peek(iter->array_buffer->buffer, cpu, ts, lost_events); + } if (event) { iter->ent_size = ring_buffer_event_length(event); @@ -3121,7 +3528,7 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu, unsigned long *missing_events, u64 *ent_ts) { - struct ring_buffer *buffer = iter->trace_buffer->buffer; + struct trace_buffer *buffer = iter->array_buffer->buffer; struct trace_entry *ent, *next = NULL; unsigned long lost_events = 0, next_lost = 0; int cpu_file = iter->cpu_file; @@ -3177,11 +3584,53 @@ return next; } +#define STATIC_TEMP_BUF_SIZE 128 +static char static_temp_buf[STATIC_TEMP_BUF_SIZE] __aligned(4); + /* Find the next real entry, without updating the iterator itself */ struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) { - return __find_next_entry(iter, ent_cpu, NULL, ent_ts); + /* __find_next_entry will reset ent_size */ + int ent_size = iter->ent_size; + struct trace_entry *entry; + + /* + * If called from ftrace_dump(), then the iter->temp buffer + * will be the static_temp_buf and not created from kmalloc. + * If the entry size is greater than the buffer, we can + * not save it. Just return NULL in that case. This is only + * used to add markers when two consecutive events' time + * stamps have a large delta. See trace_print_lat_context() + */ + if (iter->temp == static_temp_buf && + STATIC_TEMP_BUF_SIZE < ent_size) + return NULL; + + /* + * The __find_next_entry() may call peek_next_entry(), which may + * call ring_buffer_peek() that may make the contents of iter->ent + * undefined. Need to copy iter->ent now. + */ + if (iter->ent && iter->ent != iter->temp) { + if ((!iter->temp || iter->temp_size < iter->ent_size) && + !WARN_ON_ONCE(iter->temp == static_temp_buf)) { + void *temp; + temp = kmalloc(iter->ent_size, GFP_KERNEL); + if (!temp) + return NULL; + kfree(iter->temp); + iter->temp = temp; + iter->temp_size = iter->ent_size; + } + memcpy(iter->temp, iter->ent, iter->ent_size); + iter->ent = iter->temp; + } + entry = __find_next_entry(iter, ent_cpu, NULL, ent_ts); + /* Put back the original ent_size */ + iter->ent_size = ent_size; + + return entry; } /* Find the next real entry, and increment the iterator to the next entry */ @@ -3198,7 +3647,7 @@ static void trace_consume(struct trace_iterator *iter) { - ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, &iter->ts, + ring_buffer_consume(iter->array_buffer->buffer, iter->cpu, &iter->ts, &iter->lost_events); } @@ -3231,12 +3680,11 @@ void tracing_iter_reset(struct trace_iterator *iter, int cpu) { - struct ring_buffer_event *event; struct ring_buffer_iter *buf_iter; unsigned long entries = 0; u64 ts; - per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = 0; + per_cpu_ptr(iter->array_buffer->data, cpu)->skipped_entries = 0; buf_iter = trace_buffer_iter(iter, cpu); if (!buf_iter) @@ -3249,14 +3697,14 @@ * that a reset never took place on a cpu. This is evident * by the timestamp being before the start of the buffer. */ - while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { - if (ts >= iter->trace_buffer->time_start) + while (ring_buffer_iter_peek(buf_iter, &ts)) { + if (ts >= iter->array_buffer->time_start) break; entries++; - ring_buffer_read(buf_iter, NULL); + ring_buffer_iter_advance(buf_iter); } - per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = entries; + per_cpu_ptr(iter->array_buffer->data, cpu)->skipped_entries = entries; } /* @@ -3279,8 +3727,15 @@ * will point to the same string as current_trace->name. */ mutex_lock(&trace_types_lock); - if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) + if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) { + /* Close iter->trace before switching to the new current tracer */ + if (iter->trace->close) + iter->trace->close(iter); *iter->trace = *tr->current_trace; + /* Reopen the new current tracer */ + if (iter->trace->open) + iter->trace->open(iter); + } mutex_unlock(&trace_types_lock); #ifdef CONFIG_TRACER_MAX_TRACE @@ -3335,49 +3790,81 @@ } static void -get_total_entries(struct trace_buffer *buf, - unsigned long *total, unsigned long *entries) +get_total_entries_cpu(struct array_buffer *buf, unsigned long *total, + unsigned long *entries, int cpu) { unsigned long count; + + count = ring_buffer_entries_cpu(buf->buffer, cpu); + /* + * If this buffer has skipped entries, then we hold all + * entries for the trace and we need to ignore the + * ones before the time stamp. + */ + if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { + count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; + /* total is the same as the entries */ + *total = count; + } else + *total = count + + ring_buffer_overrun_cpu(buf->buffer, cpu); + *entries = count; +} + +static void +get_total_entries(struct array_buffer *buf, + unsigned long *total, unsigned long *entries) +{ + unsigned long t, e; int cpu; *total = 0; *entries = 0; for_each_tracing_cpu(cpu) { - count = ring_buffer_entries_cpu(buf->buffer, cpu); - /* - * If this buffer has skipped entries, then we hold all - * entries for the trace and we need to ignore the - * ones before the time stamp. - */ - if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { - count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; - /* total is the same as the entries */ - *total += count; - } else - *total += count + - ring_buffer_overrun_cpu(buf->buffer, cpu); - *entries += count; + get_total_entries_cpu(buf, &t, &e, cpu); + *total += t; + *entries += e; } +} + +unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu) +{ + unsigned long total, entries; + + if (!tr) + tr = &global_trace; + + get_total_entries_cpu(&tr->array_buffer, &total, &entries, cpu); + + return entries; +} + +unsigned long trace_total_entries(struct trace_array *tr) +{ + unsigned long total, entries; + + if (!tr) + tr = &global_trace; + + get_total_entries(&tr->array_buffer, &total, &entries); + + return entries; } static void print_lat_help_header(struct seq_file *m) { - seq_puts(m, "# _--------=> CPU# \n" - "# / _-------=> irqs-off \n" - "# | / _------=> need-resched \n" - "# || / _-----=> need-resched_lazy \n" - "# ||| / _----=> hardirq/softirq \n" - "# |||| / _---=> preempt-depth \n" - "# ||||| / _--=> preempt-lazy-depth\n" - "# |||||| / _-=> migrate-disable \n" - "# ||||||| / delay \n" - "# cmd pid |||||||| time | caller \n" - "# \\ / |||||||| \\ | / \n"); + seq_puts(m, "# _------=> CPU# \n" + "# / _-----=> irqs-off \n" + "# | / _----=> need-resched \n" + "# || / _---=> hardirq/softirq \n" + "# ||| / _--=> preempt-depth \n" + "# |||| / delay \n" + "# cmd pid ||||| time | caller \n" + "# \\ / ||||| \\ | / \n"); } -static void print_event_info(struct trace_buffer *buf, struct seq_file *m) +static void print_event_info(struct array_buffer *buf, struct seq_file *m) { unsigned long total; unsigned long entries; @@ -3388,49 +3875,40 @@ seq_puts(m, "#\n"); } -static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m, +static void print_func_help_header(struct array_buffer *buf, struct seq_file *m, unsigned int flags) { bool tgid = flags & TRACE_ITER_RECORD_TGID; print_event_info(buf, m); - seq_printf(m, "# TASK-PID %s CPU# TIMESTAMP FUNCTION\n", tgid ? "TGID " : ""); - seq_printf(m, "# | | %s | | |\n", tgid ? " | " : ""); + seq_printf(m, "# TASK-PID %s CPU# TIMESTAMP FUNCTION\n", tgid ? " TGID " : ""); + seq_printf(m, "# | | %s | | |\n", tgid ? " | " : ""); } -static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m, +static void print_func_help_header_irq(struct array_buffer *buf, struct seq_file *m, unsigned int flags) { bool tgid = flags & TRACE_ITER_RECORD_TGID; - const char tgid_space[] = " "; - const char space[] = " "; + const char *space = " "; + int prec = tgid ? 12 : 2; print_event_info(buf, m); - seq_printf(m, "# %s _-----=> irqs-off\n", - tgid ? tgid_space : space); - seq_printf(m, "# %s / _----=> need-resched\n", - tgid ? tgid_space : space); - seq_printf(m, "# %s| / _---=> need-resched_lazy\n", - tgid ? tgid_space : space); - seq_printf(m, "# %s|| / _--=> hardirq/softirq\n", - tgid ? tgid_space : space); - seq_printf(m, "# %s||| / preempt-depth\n", - tgid ? tgid_space : space); - seq_printf(m, "# %s|||| / delay\n", - tgid ? tgid_space : space); - seq_printf(m, "# TASK-PID %sCPU# ||||| TIMESTAMP FUNCTION\n", - tgid ? " TGID " : space); - seq_printf(m, "# | | %s | ||||| | |\n", - tgid ? " | " : space); + seq_printf(m, "# %.*s _-----=> irqs-off\n", prec, space); + seq_printf(m, "# %.*s / _----=> need-resched\n", prec, space); + seq_printf(m, "# %.*s| / _---=> hardirq/softirq\n", prec, space); + seq_printf(m, "# %.*s|| / _--=> preempt-depth\n", prec, space); + seq_printf(m, "# %.*s||| / delay\n", prec, space); + seq_printf(m, "# TASK-PID %.*s CPU# |||| TIMESTAMP FUNCTION\n", prec, " TGID "); + seq_printf(m, "# | | %.*s | |||| | |\n", prec, " | "); } void print_trace_header(struct seq_file *m, struct trace_iterator *iter) { unsigned long sym_flags = (global_trace.trace_flags & TRACE_ITER_SYM_MASK); - struct trace_buffer *buf = iter->trace_buffer; + struct array_buffer *buf = iter->array_buffer; struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); struct tracer *type = iter->trace; unsigned long entries; @@ -3457,6 +3935,8 @@ "desktop", #elif defined(CONFIG_PREEMPT) "preempt", +#elif defined(CONFIG_PREEMPT_RT) + "preempt_rt", #else "unknown", #endif @@ -3503,7 +3983,7 @@ cpumask_test_cpu(iter->cpu, iter->started)) return; - if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries) + if (per_cpu_ptr(iter->array_buffer->data, iter->cpu)->skipped_entries) return; if (cpumask_available(iter->started)) @@ -3637,7 +4117,7 @@ if (!ring_buffer_iter_empty(buf_iter)) return 0; } else { - if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) + if (!ring_buffer_empty_cpu(iter->array_buffer->buffer, cpu)) return 0; } return 1; @@ -3649,7 +4129,7 @@ if (!ring_buffer_iter_empty(buf_iter)) return 0; } else { - if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) + if (!ring_buffer_empty_cpu(iter->array_buffer->buffer, cpu)) return 0; } } @@ -3665,8 +4145,12 @@ enum print_line_t ret; if (iter->lost_events) { - trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", - iter->cpu, iter->lost_events); + if (iter->lost_events == (unsigned long)-1) + trace_seq_printf(&iter->seq, "CPU:%d [LOST EVENTS]\n", + iter->cpu); + else + trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", + iter->cpu, iter->lost_events); if (trace_seq_has_overflowed(&iter->seq)) return TRACE_TYPE_PARTIAL_LINE; } @@ -3739,10 +4223,10 @@ } else { if (!(trace_flags & TRACE_ITER_VERBOSE)) { if (trace_flags & TRACE_ITER_IRQ_INFO) - print_func_help_header_irq(iter->trace_buffer, + print_func_help_header_irq(iter->array_buffer, m, trace_flags); else - print_func_help_header(iter->trace_buffer, m, + print_func_help_header(iter->array_buffer, m, trace_flags); } } @@ -3882,6 +4366,18 @@ goto release; /* + * trace_find_next_entry() may need to save off iter->ent. + * It will place it into the iter->temp buffer. As most + * events are less than 128, allocate a buffer of that size. + * If one is greater, then trace_find_next_entry() will + * allocate a new buffer to adjust for the bigger iter->ent. + * It's not critical if it fails to get allocated here. + */ + iter->temp = kmalloc(128, GFP_KERNEL); + if (iter->temp) + iter->temp_size = 128; + + /* * We make a copy of the current tracer to avoid concurrent * changes on it while we are reading. */ @@ -3900,35 +4396,38 @@ #ifdef CONFIG_TRACER_MAX_TRACE /* Currently only the top directory has a snapshot */ if (tr->current_trace->print_max || snapshot) - iter->trace_buffer = &tr->max_buffer; + iter->array_buffer = &tr->max_buffer; else #endif - iter->trace_buffer = &tr->trace_buffer; + iter->array_buffer = &tr->array_buffer; iter->snapshot = snapshot; iter->pos = -1; iter->cpu_file = tracing_get_cpu(inode); mutex_init(&iter->mutex); /* Notify the tracer early; before we stop tracing. */ - if (iter->trace && iter->trace->open) + if (iter->trace->open) iter->trace->open(iter); /* Annotate start of buffers if we had overruns */ - if (ring_buffer_overruns(iter->trace_buffer->buffer)) + if (ring_buffer_overruns(iter->array_buffer->buffer)) iter->iter_flags |= TRACE_FILE_ANNOTATE; /* Output in nanoseconds only if we are using a clock in nanoseconds. */ if (trace_clocks[tr->clock_id].in_ns) iter->iter_flags |= TRACE_FILE_TIME_IN_NS; - /* stop the trace while dumping if we are not opening "snapshot" */ - if (!iter->snapshot) + /* + * If pause-on-trace is enabled, then stop the trace while + * dumping, unless this is the "snapshot" file + */ + if (!iter->snapshot && (tr->trace_flags & TRACE_ITER_PAUSE_ON_TRACE)) tracing_stop_tr(tr); if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { for_each_tracing_cpu(cpu) { iter->buffer_iter[cpu] = - ring_buffer_read_prepare(iter->trace_buffer->buffer, + ring_buffer_read_prepare(iter->array_buffer->buffer, cpu, GFP_KERNEL); } ring_buffer_read_prepare_sync(); @@ -3939,7 +4438,7 @@ } else { cpu = iter->cpu_file; iter->buffer_iter[cpu] = - ring_buffer_read_prepare(iter->trace_buffer->buffer, + ring_buffer_read_prepare(iter->array_buffer->buffer, cpu, GFP_KERNEL); ring_buffer_read_prepare_sync(); ring_buffer_read_start(iter->buffer_iter[cpu]); @@ -3953,6 +4452,7 @@ fail: mutex_unlock(&trace_types_lock); kfree(iter->trace); + kfree(iter->temp); kfree(iter->buffer_iter); release: seq_release_private(inode, file); @@ -3961,8 +4461,11 @@ int tracing_open_generic(struct inode *inode, struct file *filp) { - if (tracing_disabled) - return -ENODEV; + int ret; + + ret = tracing_check_open_get_tr(NULL); + if (ret) + return ret; filp->private_data = inode->i_private; return 0; @@ -3977,17 +4480,43 @@ * Open and update trace_array ref count. * Must have the current trace_array passed to it. */ -static int tracing_open_generic_tr(struct inode *inode, struct file *filp) +int tracing_open_generic_tr(struct inode *inode, struct file *filp) { struct trace_array *tr = inode->i_private; + int ret; - if (tracing_disabled) - return -ENODEV; - - if (trace_array_get(tr) < 0) - return -ENODEV; + ret = tracing_check_open_get_tr(tr); + if (ret) + return ret; filp->private_data = inode->i_private; + + return 0; +} + +/* + * The private pointer of the inode is the trace_event_file. + * Update the tr ref count associated to it. + */ +int tracing_open_file_tr(struct inode *inode, struct file *filp) +{ + struct trace_event_file *file = inode->i_private; + int ret; + + ret = tracing_check_open_get_tr(file->tr); + if (ret) + return ret; + + filp->private_data = inode->i_private; + + return 0; +} + +int tracing_release_file_tr(struct inode *inode, struct file *filp) +{ + struct trace_event_file *file = inode->i_private; + + trace_array_put(file->tr); return 0; } @@ -4016,7 +4545,7 @@ if (iter->trace && iter->trace->close) iter->trace->close(iter); - if (!iter->snapshot) + if (!iter->snapshot && tr->stop_count) /* reenable tracing if it was previously enabled */ tracing_start_tr(tr); @@ -4026,6 +4555,7 @@ mutex_destroy(&iter->mutex); free_cpumask_var(iter->started); + kfree(iter->temp); kfree(iter->trace); kfree(iter->buffer_iter); seq_release_private(inode, file); @@ -4054,15 +4584,16 @@ { struct trace_array *tr = inode->i_private; struct trace_iterator *iter; - int ret = 0; + int ret; - if (trace_array_get(tr) < 0) - return -ENODEV; + ret = tracing_check_open_get_tr(tr); + if (ret) + return ret; /* If this file was open for write, then erase contents */ if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { int cpu = tracing_get_cpu(inode); - struct trace_buffer *trace_buf = &tr->trace_buffer; + struct array_buffer *trace_buf = &tr->array_buffer; #ifdef CONFIG_TRACER_MAX_TRACE if (tr->current_trace->print_max) @@ -4072,7 +4603,7 @@ if (cpu == RING_BUFFER_ALL_CPUS) tracing_reset_online_cpus(trace_buf); else - tracing_reset(trace_buf, cpu); + tracing_reset_cpu(trace_buf, cpu); } if (file->f_mode & FMODE_READ) { @@ -4173,11 +4704,9 @@ struct seq_file *m; int ret; - if (tracing_disabled) - return -ENODEV; - - if (trace_array_get(tr) < 0) - return -ENODEV; + ret = tracing_check_open_get_tr(tr); + if (ret) + return ret; ret = seq_open(file, &show_traces_seq_ops); if (ret) { @@ -4221,6 +4750,8 @@ static const struct file_operations tracing_fops = { .open = tracing_open, .read = seq_read, + .read_iter = seq_read_iter, + .splice_read = generic_file_splice_read, .write = tracing_write_stub, .llseek = tracing_lseek, .release = tracing_release, @@ -4261,20 +4792,13 @@ return count; } -static ssize_t -tracing_cpumask_write(struct file *filp, const char __user *ubuf, - size_t count, loff_t *ppos) +int tracing_set_cpumask(struct trace_array *tr, + cpumask_var_t tracing_cpumask_new) { - struct trace_array *tr = file_inode(filp)->i_private; - cpumask_var_t tracing_cpumask_new; - int err, cpu; + int cpu; - if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) - return -ENOMEM; - - err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); - if (err) - goto err_unlock; + if (!tr) + return -EINVAL; local_irq_disable(); arch_spin_lock(&tr->max_lock); @@ -4285,24 +4809,53 @@ */ if (cpumask_test_cpu(cpu, tr->tracing_cpumask) && !cpumask_test_cpu(cpu, tracing_cpumask_new)) { - atomic_inc(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); - ring_buffer_record_disable_cpu(tr->trace_buffer.buffer, cpu); + atomic_inc(&per_cpu_ptr(tr->array_buffer.data, cpu)->disabled); + ring_buffer_record_disable_cpu(tr->array_buffer.buffer, cpu); +#ifdef CONFIG_TRACER_MAX_TRACE + ring_buffer_record_disable_cpu(tr->max_buffer.buffer, cpu); +#endif } if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) && cpumask_test_cpu(cpu, tracing_cpumask_new)) { - atomic_dec(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); - ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu); + atomic_dec(&per_cpu_ptr(tr->array_buffer.data, cpu)->disabled); + ring_buffer_record_enable_cpu(tr->array_buffer.buffer, cpu); +#ifdef CONFIG_TRACER_MAX_TRACE + ring_buffer_record_enable_cpu(tr->max_buffer.buffer, cpu); +#endif } } arch_spin_unlock(&tr->max_lock); local_irq_enable(); cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new); + + return 0; +} + +static ssize_t +tracing_cpumask_write(struct file *filp, const char __user *ubuf, + size_t count, loff_t *ppos) +{ + struct trace_array *tr = file_inode(filp)->i_private; + cpumask_var_t tracing_cpumask_new; + int err; + + if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) + return -ENOMEM; + + err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); + if (err) + goto err_free; + + err = tracing_set_cpumask(tr, tracing_cpumask_new); + if (err) + goto err_free; + free_cpumask_var(tracing_cpumask_new); return count; -err_unlock: +err_free: free_cpumask_var(tracing_cpumask_new); return err; @@ -4444,7 +4997,7 @@ ftrace_pid_follow_fork(tr, enabled); if (mask == TRACE_ITER_OVERWRITE) { - ring_buffer_change_overwrite(tr->trace_buffer.buffer, enabled); + ring_buffer_change_overwrite(tr->array_buffer.buffer, enabled); #ifdef CONFIG_TRACER_MAX_TRACE ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled); #endif @@ -4458,19 +5011,21 @@ return 0; } -static int trace_set_options(struct trace_array *tr, char *option) +int trace_set_options(struct trace_array *tr, char *option) { char *cmp; int neg = 0; int ret; size_t orig_len = strlen(option); + int len; cmp = strstrip(option); - if (strncmp(cmp, "no", 2) == 0) { + len = str_has_prefix(cmp, "no"); + if (len) neg = 1; - cmp += 2; - } + + cmp += len; mutex_lock(&event_mutex); mutex_lock(&trace_types_lock); @@ -4546,11 +5101,9 @@ struct trace_array *tr = inode->i_private; int ret; - if (tracing_disabled) - return -ENODEV; - - if (trace_array_get(tr) < 0) - return -ENODEV; + ret = tracing_check_open_get_tr(tr); + if (ret) + return ret; ret = single_open(file, tracing_trace_options_show, inode->i_private); if (ret < 0) @@ -4577,6 +5130,7 @@ " trace_pipe\t\t- A consuming read to see the contents of the buffer\n" " current_tracer\t- function and latency tracers\n" " available_tracers\t- list of configured tracers for current_tracer\n" + " error_log\t- error log for failed commands (that support it)\n" " buffer_size_kb\t- view and modify size of per cpu buffer\n" " buffer_total_size_kb - view total size of all cpu buffers\n\n" " trace_clock\t\t-change the clock used to order events\n" @@ -4597,7 +5151,7 @@ " instances\t\t- Make sub-buffers with: mkdir instances/foo\n" "\t\t\t Remove sub-buffer with rmdir\n" " trace_options\t\t- Set format or modify how tracing happens\n" - "\t\t\t Disable an option by adding a suffix 'no' to the\n" + "\t\t\t Disable an option by prefixing 'no' to the\n" "\t\t\t option name\n" " saved_cmdlines_size\t- echo command number in here to store comm-pid list\n" #ifdef CONFIG_DYNAMIC_FTRACE @@ -4641,6 +5195,8 @@ #ifdef CONFIG_FUNCTION_TRACER " set_ftrace_pid\t- Write pid(s) to only function trace those pids\n" "\t\t (function)\n" + " set_ftrace_notrace_pid\t- Write pid(s) to not function trace those pids\n" + "\t\t (function)\n" #endif #ifdef CONFIG_FUNCTION_GRAPH_TRACER " set_graph_function\t- Trace the nested calls of a function (function_graph)\n" @@ -4662,31 +5218,49 @@ "\t\t\t traces\n" #endif #endif /* CONFIG_STACK_TRACER */ +#ifdef CONFIG_DYNAMIC_EVENTS + " dynamic_events\t\t- Create/append/remove/show the generic dynamic events\n" + "\t\t\t Write into this file to define/undefine new trace events.\n" +#endif #ifdef CONFIG_KPROBE_EVENTS - " kprobe_events\t\t- Add/remove/show the kernel dynamic events\n" + " kprobe_events\t\t- Create/append/remove/show the kernel dynamic events\n" "\t\t\t Write into this file to define/undefine new trace events.\n" #endif #ifdef CONFIG_UPROBE_EVENTS - " uprobe_events\t\t- Add/remove/show the userspace dynamic events\n" + " uprobe_events\t\t- Create/append/remove/show the userspace dynamic events\n" "\t\t\t Write into this file to define/undefine new trace events.\n" #endif #if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) "\t accepts: event-definitions (one definition per line)\n" "\t Format: p[:[<group>/]<event>] <place> [<args>]\n" "\t r[maxactive][:[<group>/]<event>] <place> [<args>]\n" +#ifdef CONFIG_HIST_TRIGGERS + "\t s:[synthetic/]<event> <field> [<field>]\n" +#endif "\t -:[<group>/]<event>\n" #ifdef CONFIG_KPROBE_EVENTS "\t place: [<module>:]<symbol>[+<offset>]|<memaddr>\n" - "place (kretprobe): [<module>:]<symbol>[+<offset>]|<memaddr>\n" + "place (kretprobe): [<module>:]<symbol>[+<offset>]%return|<memaddr>\n" #endif #ifdef CONFIG_UPROBE_EVENTS - "\t place: <path>:<offset>\n" + " place (uprobe): <path>:<offset>[%return][(ref_ctr_offset)]\n" #endif "\t args: <name>=fetcharg[:type]\n" "\t fetcharg: %<register>, @<address>, @<symbol>[+|-<offset>],\n" - "\t $stack<index>, $stack, $retval, $comm\n" - "\t type: s8/16/32/64, u8/16/32/64, x8/16/32/64, string,\n" - "\t b<bit-width>@<bit-offset>/<container-size>\n" +#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API + "\t $stack<index>, $stack, $retval, $comm, $arg<N>,\n" +#else + "\t $stack<index>, $stack, $retval, $comm,\n" +#endif + "\t +|-[u]<offset>(<fetcharg>), \\imm-value, \\\"imm-string\"\n" + "\t type: s8/16/32/64, u8/16/32/64, x8/16/32/64, string, symbol,\n" + "\t b<bit-width>@<bit-offset>/<container-size>, ustring,\n" + "\t <type>\\[<array-size>\\]\n" +#ifdef CONFIG_HIST_TRIGGERS + "\t field: <stype> <name>;\n" + "\t stype: u8/u16/u32/u64, s8/s16/s32/s64, pid_t,\n" + "\t [unsigned] char/int/long\n" +#endif #endif " events/\t\t- Directory containing all trace event subsystems:\n" " enable\t\t- Write 0/1 to enable/disable tracing of all events\n" @@ -4739,6 +5313,7 @@ "\t [:size=#entries]\n" "\t [:pause][:continue][:clear]\n" "\t [:name=histname1]\n" + "\t [:<handler>.<action>]\n" "\t [if <filter>]\n\n" "\t Note, special fields can be used as well:\n" "\t common_timestamp - to record current timestamp\n" @@ -4783,8 +5358,26 @@ "\t unchanged.\n\n" "\t The enable_hist and disable_hist triggers can be used to\n" "\t have one event conditionally start and stop another event's\n" - "\t already-attached hist trigger. The syntax is analagous to\n" - "\t the enable_event and disable_event triggers.\n" + "\t already-attached hist trigger. The syntax is analogous to\n" + "\t the enable_event and disable_event triggers.\n\n" + "\t Hist trigger handlers and actions are executed whenever a\n" + "\t a histogram entry is added or updated. They take the form:\n\n" + "\t <handler>.<action>\n\n" + "\t The available handlers are:\n\n" + "\t onmatch(matching.event) - invoke on addition or update\n" + "\t onmax(var) - invoke if var exceeds current max\n" + "\t onchange(var) - invoke action if var changes\n\n" + "\t The available actions are:\n\n" + "\t trace(<synthetic_event>,param list) - generate synthetic event\n" + "\t save(field,...) - save current event fields\n" +#ifdef CONFIG_TRACER_SNAPSHOT + "\t snapshot() - snapshot the trace buffer\n\n" +#endif +#ifdef CONFIG_SYNTH_EVENTS + " events/synthetic_events\t- Create/append/remove/show synthetic events\n" + "\t Write into this file to define/undefine new synthetic events.\n" + "\t example: echo 'myevent u64 lat; char name[]' >> synthetic_events\n" +#endif #endif ; @@ -4842,8 +5435,11 @@ static int tracing_saved_tgids_open(struct inode *inode, struct file *filp) { - if (tracing_disabled) - return -ENODEV; + int ret; + + ret = tracing_check_open_get_tr(NULL); + if (ret) + return ret; return seq_open(filp, &tracing_saved_tgids_seq_ops); } @@ -4919,8 +5515,11 @@ static int tracing_saved_cmdlines_open(struct inode *inode, struct file *filp) { - if (tracing_disabled) - return -ENODEV; + int ret; + + ret = tracing_check_open_get_tr(NULL); + if (ret) + return ret; return seq_open(filp, &tracing_saved_cmdlines_seq_ops); } @@ -4939,9 +5538,11 @@ char buf[64]; int r; + preempt_disable(); arch_spin_lock(&trace_cmdline_lock); r = scnprintf(buf, sizeof(buf), "%u\n", savedcmd->cmdline_num); arch_spin_unlock(&trace_cmdline_lock); + preempt_enable(); return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); } @@ -4966,10 +5567,12 @@ return -ENOMEM; } + preempt_disable(); arch_spin_lock(&trace_cmdline_lock); savedcmd_temp = savedcmd; savedcmd = s; arch_spin_unlock(&trace_cmdline_lock); + preempt_enable(); free_saved_cmdlines_buffer(savedcmd_temp); return 0; @@ -5028,14 +5631,12 @@ * Paranoid! If ptr points to end, we don't want to increment past it. * This really should never happen. */ + (*pos)++; ptr = update_eval_map(ptr); if (WARN_ON_ONCE(!ptr)) return NULL; ptr++; - - (*pos)++; - ptr = update_eval_map(ptr); return ptr; @@ -5084,8 +5685,11 @@ static int tracing_eval_map_open(struct inode *inode, struct file *filp) { - if (tracing_disabled) - return -ENODEV; + int ret; + + ret = tracing_check_open_get_tr(NULL); + if (ret) + return ret; return seq_open(filp, &tracing_eval_map_seq_ops); } @@ -5198,11 +5802,11 @@ int tracer_init(struct tracer *t, struct trace_array *tr) { - tracing_reset_online_cpus(&tr->trace_buffer); + tracing_reset_online_cpus(&tr->array_buffer); return t->init(tr); } -static void set_buffer_entries(struct trace_buffer *buf, unsigned long val) +static void set_buffer_entries(struct array_buffer *buf, unsigned long val) { int cpu; @@ -5212,8 +5816,8 @@ #ifdef CONFIG_TRACER_MAX_TRACE /* resize @tr's buffer to the size of @size_tr's entries */ -static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, - struct trace_buffer *size_buf, int cpu_id) +static int resize_buffer_duplicate_size(struct array_buffer *trace_buf, + struct array_buffer *size_buf, int cpu_id) { int cpu, ret = 0; @@ -5251,10 +5855,10 @@ ring_buffer_expanded = true; /* May be called before buffers are initialized */ - if (!tr->trace_buffer.buffer) + if (!tr->array_buffer.buffer) return 0; - ret = ring_buffer_resize(tr->trace_buffer.buffer, size, cpu); + ret = ring_buffer_resize(tr->array_buffer.buffer, size, cpu); if (ret < 0) return ret; @@ -5265,8 +5869,8 @@ ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu); if (ret < 0) { - int r = resize_buffer_duplicate_size(&tr->trace_buffer, - &tr->trace_buffer, cpu); + int r = resize_buffer_duplicate_size(&tr->array_buffer, + &tr->array_buffer, cpu); if (r < 0) { /* * AARGH! We are left with different @@ -5297,15 +5901,15 @@ #endif /* CONFIG_TRACER_MAX_TRACE */ if (cpu == RING_BUFFER_ALL_CPUS) - set_buffer_entries(&tr->trace_buffer, size); + set_buffer_entries(&tr->array_buffer, size); else - per_cpu_ptr(tr->trace_buffer.data, cpu)->entries = size; + per_cpu_ptr(tr->array_buffer.data, cpu)->entries = size; return ret; } -static ssize_t tracing_resize_ring_buffer(struct trace_array *tr, - unsigned long size, int cpu_id) +ssize_t tracing_resize_ring_buffer(struct trace_array *tr, + unsigned long size, int cpu_id) { int ret = size; @@ -5375,16 +5979,22 @@ tr->current_trace = &nop_trace; } +static bool tracer_options_updated; + static void add_tracer_options(struct trace_array *tr, struct tracer *t) { /* Only enable if the directory has been created already. */ if (!tr->dir) return; + /* Only create trace option files after update_tracer_options finish */ + if (!tracer_options_updated) + return; + create_trace_option_files(tr, t); } -static int tracing_set_tracer(struct trace_array *tr, const char *buf) +int tracing_set_tracer(struct trace_array *tr, const char *buf) { struct tracer *t; #ifdef CONFIG_TRACER_MAX_TRACE @@ -5413,6 +6023,18 @@ if (t == tr->current_trace) goto out; +#ifdef CONFIG_TRACER_SNAPSHOT + if (t->use_max_tr) { + local_irq_disable(); + arch_spin_lock(&tr->max_lock); + if (tr->cond_snapshot) + ret = -EBUSY; + arch_spin_unlock(&tr->max_lock); + local_irq_enable(); + if (ret) + goto out; + } +#endif /* Some tracers won't work on kernel command line */ if (system_state < SYSTEM_RUNNING && t->noboot) { pr_warn("Tracer '%s' is not allowed on command line, ignored\n", @@ -5427,7 +6049,7 @@ } /* If trace pipe files are being read, we can't change the tracer */ - if (tr->current_trace->ref) { + if (tr->trace_ref) { ret = -EBUSY; goto out; } @@ -5439,11 +6061,11 @@ if (tr->current_trace->reset) tr->current_trace->reset(tr); - /* Current trace needs to be nop_trace before synchronize_sched */ - tr->current_trace = &nop_trace; - #ifdef CONFIG_TRACER_MAX_TRACE - had_max_tr = tr->allocated_snapshot; + had_max_tr = tr->current_trace->use_max_tr; + + /* Current trace needs to be nop_trace before synchronize_rcu */ + tr->current_trace = &nop_trace; if (had_max_tr && !t->use_max_tr) { /* @@ -5453,17 +6075,17 @@ * The update_max_tr is called from interrupts disabled * so a synchronized_sched() is sufficient. */ - synchronize_sched(); + synchronize_rcu(); free_snapshot(tr); } -#endif -#ifdef CONFIG_TRACER_MAX_TRACE - if (t->use_max_tr && !had_max_tr) { + if (t->use_max_tr && !tr->allocated_snapshot) { ret = tracing_alloc_snapshot_instance(tr); if (ret < 0) goto out; } +#else + tr->current_trace = &nop_trace; #endif if (t->init) { @@ -5598,13 +6220,11 @@ { struct trace_array *tr = inode->i_private; struct trace_iterator *iter; - int ret = 0; + int ret; - if (tracing_disabled) - return -ENODEV; - - if (trace_array_get(tr) < 0) - return -ENODEV; + ret = tracing_check_open_get_tr(tr); + if (ret) + return ret; mutex_lock(&trace_types_lock); @@ -5635,7 +6255,7 @@ iter->iter_flags |= TRACE_FILE_TIME_IN_NS; iter->tr = tr; - iter->trace_buffer = &tr->trace_buffer; + iter->array_buffer = &tr->array_buffer; iter->cpu_file = tracing_get_cpu(inode); mutex_init(&iter->mutex); filp->private_data = iter; @@ -5645,7 +6265,7 @@ nonseekable_open(inode, filp); - tr->current_trace->ref++; + tr->trace_ref++; out: mutex_unlock(&trace_types_lock); return ret; @@ -5664,7 +6284,7 @@ mutex_lock(&trace_types_lock); - tr->current_trace->ref--; + tr->trace_ref--; if (iter->trace->pipe_close) iter->trace->pipe_close(iter); @@ -5672,6 +6292,7 @@ mutex_unlock(&trace_types_lock); free_cpumask_var(iter->started); + kfree(iter->temp); mutex_destroy(&iter->mutex); kfree(iter); @@ -5695,8 +6316,8 @@ */ return EPOLLIN | EPOLLRDNORM; else - return ring_buffer_poll_wait(iter->trace_buffer->buffer, iter->cpu_file, - filp, poll_table); + return ring_buffer_poll_wait(iter->array_buffer->buffer, iter->cpu_file, + filp, poll_table, iter->tr->buffer_percent); } static __poll_t @@ -5733,7 +6354,7 @@ mutex_unlock(&iter->mutex); - ret = wait_on_pipe(iter, false); + ret = wait_on_pipe(iter, 0); mutex_lock(&iter->mutex); @@ -5804,7 +6425,20 @@ ret = print_trace_line(iter); if (ret == TRACE_TYPE_PARTIAL_LINE) { - /* don't print partial lines */ + /* + * If one print_trace_line() fills entire trace_seq in one shot, + * trace_seq_to_user() will returns -EBUSY because save_len == 0, + * In this case, we need to consume it, otherwise, loop will peek + * this event next time, resulting in an infinite loop. + */ + if (save_len == 0) { + iter->seq.full = 0; + trace_seq_puts(&iter->seq, "[LINE TOO BIG]\n"); + trace_consume(iter); + break; + } + + /* In other cases, don't print partial lines */ iter->seq.seq.len = save_len; break; } @@ -5848,14 +6482,6 @@ { __free_page(spd->pages[idx]); } - -static const struct pipe_buf_operations tracing_pipe_buf_ops = { - .can_merge = 0, - .confirm = generic_pipe_buf_confirm, - .release = generic_pipe_buf_release, - .steal = generic_pipe_buf_steal, - .get = generic_pipe_buf_get, -}; static size_t tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) @@ -5918,7 +6544,7 @@ .partial = partial_def, .nr_pages = 0, /* This gets updated below. */ .nr_pages_max = PIPE_DEF_BUFFERS, - .ops = &tracing_pipe_buf_ops, + .ops = &default_pipe_buf_ops, .spd_release = tracing_spd_release_pipe, }; ssize_t ret; @@ -6013,8 +6639,8 @@ for_each_tracing_cpu(cpu) { /* fill in the size from first enabled cpu */ if (size == 0) - size = per_cpu_ptr(tr->trace_buffer.data, cpu)->entries; - if (size != per_cpu_ptr(tr->trace_buffer.data, cpu)->entries) { + size = per_cpu_ptr(tr->array_buffer.data, cpu)->entries; + if (size != per_cpu_ptr(tr->array_buffer.data, cpu)->entries) { buf_size_same = 0; break; } @@ -6030,7 +6656,7 @@ } else r = sprintf(buf, "X\n"); } else - r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10); + r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->array_buffer.data, cpu)->entries >> 10); mutex_unlock(&trace_types_lock); @@ -6077,7 +6703,7 @@ mutex_lock(&trace_types_lock); for_each_tracing_cpu(cpu) { - size += per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10; + size += per_cpu_ptr(tr->array_buffer.data, cpu)->entries >> 10; if (!ring_buffer_expanded) expanded_size += trace_buf_size >> 10; } @@ -6127,16 +6753,16 @@ struct trace_array *tr = filp->private_data; struct ring_buffer_event *event; enum event_trigger_type tt = ETT_NONE; - struct ring_buffer *buffer; + struct trace_buffer *buffer; struct print_entry *entry; unsigned long irq_flags; - const char faulted[] = "<faulted>"; ssize_t written; int size; int len; /* Used in tracing_mark_raw_write() as well */ -#define FAULTED_SIZE (sizeof(faulted) - 1) /* '\0' is already accounted for */ +#define FAULTED_STR "<faulted>" +#define FAULTED_SIZE (sizeof(FAULTED_STR) - 1) /* '\0' is already accounted for */ if (tracing_disabled) return -EINVAL; @@ -6156,7 +6782,7 @@ if (cnt < FAULTED_SIZE) size += FAULTED_SIZE - cnt; - buffer = tr->trace_buffer.buffer; + buffer = tr->array_buffer.buffer; event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, irq_flags, preempt_count()); if (unlikely(!event)) @@ -6168,12 +6794,11 @@ len = __copy_from_user_inatomic(&entry->buf, ubuf, cnt); if (len) { - memcpy(&entry->buf, faulted, FAULTED_SIZE); + memcpy(&entry->buf, FAULTED_STR, FAULTED_SIZE); cnt = FAULTED_SIZE; written = -EFAULT; } else written = cnt; - len = cnt; if (tr->trace_marker_file && !list_empty(&tr->trace_marker_file->triggers)) { /* do not add \n before testing triggers, but add \0 */ @@ -6187,6 +6812,8 @@ } else entry->buf[cnt] = '\0'; + if (static_branch_unlikely(&trace_marker_exports_enabled)) + ftrace_exports(event, TRACE_EXPORT_MARKER); __buffer_unlock_commit(buffer, event); if (tt) @@ -6207,9 +6834,8 @@ { struct trace_array *tr = filp->private_data; struct ring_buffer_event *event; - struct ring_buffer *buffer; + struct trace_buffer *buffer; struct raw_data_entry *entry; - const char faulted[] = "<faulted>"; unsigned long irq_flags; ssize_t written; int size; @@ -6237,7 +6863,7 @@ if (cnt < FAULT_SIZE_ID) size += FAULT_SIZE_ID - cnt; - buffer = tr->trace_buffer.buffer; + buffer = tr->array_buffer.buffer; event = __trace_buffer_lock_reserve(buffer, TRACE_RAW_DATA, size, irq_flags, preempt_count()); if (!event) @@ -6249,7 +6875,7 @@ len = __copy_from_user_inatomic(&entry->id, ubuf, cnt); if (len) { entry->id = -1; - memcpy(&entry->buf, faulted, FAULTED_SIZE); + memcpy(&entry->buf, FAULTED_STR, FAULTED_SIZE); written = -EFAULT; } else written = cnt; @@ -6292,13 +6918,13 @@ tr->clock_id = i; - ring_buffer_set_clock(tr->trace_buffer.buffer, trace_clocks[i].func); + ring_buffer_set_clock(tr->array_buffer.buffer, trace_clocks[i].func); /* * New clock may not be consistent with the previous clock. * Reset the buffer so that it doesn't have incomparable timestamps. */ - tracing_reset_online_cpus(&tr->trace_buffer); + tracing_reset_online_cpus(&tr->array_buffer); #ifdef CONFIG_TRACER_MAX_TRACE if (tr->max_buffer.buffer) @@ -6344,11 +6970,9 @@ struct trace_array *tr = inode->i_private; int ret; - if (tracing_disabled) - return -ENODEV; - - if (trace_array_get(tr)) - return -ENODEV; + ret = tracing_check_open_get_tr(tr); + if (ret) + return ret; ret = single_open(file, tracing_clock_show, inode->i_private); if (ret < 0) @@ -6363,7 +6987,7 @@ mutex_lock(&trace_types_lock); - if (ring_buffer_time_stamp_abs(tr->trace_buffer.buffer)) + if (ring_buffer_time_stamp_abs(tr->array_buffer.buffer)) seq_puts(m, "delta [absolute]\n"); else seq_puts(m, "[delta] absolute\n"); @@ -6378,11 +7002,9 @@ struct trace_array *tr = inode->i_private; int ret; - if (tracing_disabled) - return -ENODEV; - - if (trace_array_get(tr)) - return -ENODEV; + ret = tracing_check_open_get_tr(tr); + if (ret) + return ret; ret = single_open(file, tracing_time_stamp_mode_show, inode->i_private); if (ret < 0) @@ -6410,7 +7032,7 @@ goto out; } - ring_buffer_set_time_stamp_abs(tr->trace_buffer.buffer, abs); + ring_buffer_set_time_stamp_abs(tr->array_buffer.buffer, abs); #ifdef CONFIG_TRACER_MAX_TRACE if (tr->max_buffer.buffer) @@ -6435,10 +7057,11 @@ struct trace_array *tr = inode->i_private; struct trace_iterator *iter; struct seq_file *m; - int ret = 0; + int ret; - if (trace_array_get(tr) < 0) - return -ENODEV; + ret = tracing_check_open_get_tr(tr); + if (ret) + return ret; if (file->f_mode & FMODE_READ) { iter = __tracing_open(inode, file, true); @@ -6458,7 +7081,7 @@ ret = 0; iter->tr = tr; - iter->trace_buffer = &tr->max_buffer; + iter->array_buffer = &tr->max_buffer; iter->cpu_file = tracing_get_cpu(inode); m->private = iter; file->private_data = m; @@ -6468,6 +7091,11 @@ trace_array_put(tr); return ret; +} + +static void tracing_swap_cpu_buffer(void *tr) +{ + update_max_tr_single((struct trace_array *)tr, current, smp_processor_id()); } static ssize_t @@ -6495,6 +7123,15 @@ goto out; } + local_irq_disable(); + arch_spin_lock(&tr->max_lock); + if (tr->cond_snapshot) + ret = -EBUSY; + arch_spin_unlock(&tr->max_lock); + local_irq_enable(); + if (ret) + goto out; + switch (val) { case 0: if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { @@ -6514,25 +7151,27 @@ #endif if (tr->allocated_snapshot) ret = resize_buffer_duplicate_size(&tr->max_buffer, - &tr->trace_buffer, iter->cpu_file); + &tr->array_buffer, iter->cpu_file); else ret = tracing_alloc_snapshot_instance(tr); if (ret < 0) break; - local_irq_disable(); /* Now, we're going to swap */ - if (iter->cpu_file == RING_BUFFER_ALL_CPUS) - update_max_tr(tr, current, smp_processor_id()); - else - update_max_tr_single(tr, current, iter->cpu_file); - local_irq_enable(); + if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { + local_irq_disable(); + update_max_tr(tr, current, smp_processor_id(), NULL); + local_irq_enable(); + } else { + smp_call_function_single(iter->cpu_file, tracing_swap_cpu_buffer, + (void *)tr, 1); + } break; default: if (tr->allocated_snapshot) { if (iter->cpu_file == RING_BUFFER_ALL_CPUS) tracing_reset_online_cpus(&tr->max_buffer); else - tracing_reset(&tr->max_buffer, iter->cpu_file); + tracing_reset_cpu(&tr->max_buffer, iter->cpu_file); } break; } @@ -6576,6 +7215,7 @@ struct ftrace_buffer_info *info; int ret; + /* The following checks for tracefs lockdown */ ret = tracing_buffers_open(inode, filp); if (ret < 0) return ret; @@ -6588,7 +7228,7 @@ } info->iter.snapshot = true; - info->iter.trace_buffer = &info->iter.tr->max_buffer; + info->iter.array_buffer = &info->iter.tr->max_buffer; return ret; } @@ -6613,10 +7253,11 @@ #endif static const struct file_operations set_tracer_fops = { - .open = tracing_open_generic, + .open = tracing_open_generic_tr, .read = tracing_set_trace_read, .write = tracing_set_trace_write, .llseek = generic_file_llseek, + .release = tracing_release_generic_tr, }; static const struct file_operations tracing_pipe_fops = { @@ -6697,19 +7338,263 @@ #endif /* CONFIG_TRACER_SNAPSHOT */ +#define TRACING_LOG_ERRS_MAX 8 +#define TRACING_LOG_LOC_MAX 128 + +#define CMD_PREFIX " Command: " + +struct err_info { + const char **errs; /* ptr to loc-specific array of err strings */ + u8 type; /* index into errs -> specific err string */ + u8 pos; /* MAX_FILTER_STR_VAL = 256 */ + u64 ts; +}; + +struct tracing_log_err { + struct list_head list; + struct err_info info; + char loc[TRACING_LOG_LOC_MAX]; /* err location */ + char cmd[MAX_FILTER_STR_VAL]; /* what caused err */ +}; + +static DEFINE_MUTEX(tracing_err_log_lock); + +static struct tracing_log_err *get_tracing_log_err(struct trace_array *tr) +{ + struct tracing_log_err *err; + + if (tr->n_err_log_entries < TRACING_LOG_ERRS_MAX) { + err = kzalloc(sizeof(*err), GFP_KERNEL); + if (!err) + err = ERR_PTR(-ENOMEM); + else + tr->n_err_log_entries++; + + return err; + } + + err = list_first_entry(&tr->err_log, struct tracing_log_err, list); + list_del(&err->list); + + return err; +} + +/** + * err_pos - find the position of a string within a command for error careting + * @cmd: The tracing command that caused the error + * @str: The string to position the caret at within @cmd + * + * Finds the position of the first occurence of @str within @cmd. The + * return value can be passed to tracing_log_err() for caret placement + * within @cmd. + * + * Returns the index within @cmd of the first occurence of @str or 0 + * if @str was not found. + */ +unsigned int err_pos(char *cmd, const char *str) +{ + char *found; + + if (WARN_ON(!strlen(cmd))) + return 0; + + found = strstr(cmd, str); + if (found) + return found - cmd; + + return 0; +} + +/** + * tracing_log_err - write an error to the tracing error log + * @tr: The associated trace array for the error (NULL for top level array) + * @loc: A string describing where the error occurred + * @cmd: The tracing command that caused the error + * @errs: The array of loc-specific static error strings + * @type: The index into errs[], which produces the specific static err string + * @pos: The position the caret should be placed in the cmd + * + * Writes an error into tracing/error_log of the form: + * + * <loc>: error: <text> + * Command: <cmd> + * ^ + * + * tracing/error_log is a small log file containing the last + * TRACING_LOG_ERRS_MAX errors (8). Memory for errors isn't allocated + * unless there has been a tracing error, and the error log can be + * cleared and have its memory freed by writing the empty string in + * truncation mode to it i.e. echo > tracing/error_log. + * + * NOTE: the @errs array along with the @type param are used to + * produce a static error string - this string is not copied and saved + * when the error is logged - only a pointer to it is saved. See + * existing callers for examples of how static strings are typically + * defined for use with tracing_log_err(). + */ +void tracing_log_err(struct trace_array *tr, + const char *loc, const char *cmd, + const char **errs, u8 type, u8 pos) +{ + struct tracing_log_err *err; + + if (!tr) + tr = &global_trace; + + mutex_lock(&tracing_err_log_lock); + err = get_tracing_log_err(tr); + if (PTR_ERR(err) == -ENOMEM) { + mutex_unlock(&tracing_err_log_lock); + return; + } + + snprintf(err->loc, TRACING_LOG_LOC_MAX, "%s: error: ", loc); + snprintf(err->cmd, MAX_FILTER_STR_VAL,"\n" CMD_PREFIX "%s\n", cmd); + + err->info.errs = errs; + err->info.type = type; + err->info.pos = pos; + err->info.ts = local_clock(); + + list_add_tail(&err->list, &tr->err_log); + mutex_unlock(&tracing_err_log_lock); +} + +static void clear_tracing_err_log(struct trace_array *tr) +{ + struct tracing_log_err *err, *next; + + mutex_lock(&tracing_err_log_lock); + list_for_each_entry_safe(err, next, &tr->err_log, list) { + list_del(&err->list); + kfree(err); + } + + tr->n_err_log_entries = 0; + mutex_unlock(&tracing_err_log_lock); +} + +static void *tracing_err_log_seq_start(struct seq_file *m, loff_t *pos) +{ + struct trace_array *tr = m->private; + + mutex_lock(&tracing_err_log_lock); + + return seq_list_start(&tr->err_log, *pos); +} + +static void *tracing_err_log_seq_next(struct seq_file *m, void *v, loff_t *pos) +{ + struct trace_array *tr = m->private; + + return seq_list_next(v, &tr->err_log, pos); +} + +static void tracing_err_log_seq_stop(struct seq_file *m, void *v) +{ + mutex_unlock(&tracing_err_log_lock); +} + +static void tracing_err_log_show_pos(struct seq_file *m, u8 pos) +{ + u8 i; + + for (i = 0; i < sizeof(CMD_PREFIX) - 1; i++) + seq_putc(m, ' '); + for (i = 0; i < pos; i++) + seq_putc(m, ' '); + seq_puts(m, "^\n"); +} + +static int tracing_err_log_seq_show(struct seq_file *m, void *v) +{ + struct tracing_log_err *err = v; + + if (err) { + const char *err_text = err->info.errs[err->info.type]; + u64 sec = err->info.ts; + u32 nsec; + + nsec = do_div(sec, NSEC_PER_SEC); + seq_printf(m, "[%5llu.%06u] %s%s", sec, nsec / 1000, + err->loc, err_text); + seq_printf(m, "%s", err->cmd); + tracing_err_log_show_pos(m, err->info.pos); + } + + return 0; +} + +static const struct seq_operations tracing_err_log_seq_ops = { + .start = tracing_err_log_seq_start, + .next = tracing_err_log_seq_next, + .stop = tracing_err_log_seq_stop, + .show = tracing_err_log_seq_show +}; + +static int tracing_err_log_open(struct inode *inode, struct file *file) +{ + struct trace_array *tr = inode->i_private; + int ret = 0; + + ret = tracing_check_open_get_tr(tr); + if (ret) + return ret; + + /* If this file was opened for write, then erase contents */ + if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) + clear_tracing_err_log(tr); + + if (file->f_mode & FMODE_READ) { + ret = seq_open(file, &tracing_err_log_seq_ops); + if (!ret) { + struct seq_file *m = file->private_data; + m->private = tr; + } else { + trace_array_put(tr); + } + } + return ret; +} + +static ssize_t tracing_err_log_write(struct file *file, + const char __user *buffer, + size_t count, loff_t *ppos) +{ + return count; +} + +static int tracing_err_log_release(struct inode *inode, struct file *file) +{ + struct trace_array *tr = inode->i_private; + + trace_array_put(tr); + + if (file->f_mode & FMODE_READ) + seq_release(inode, file); + + return 0; +} + +static const struct file_operations tracing_err_log_fops = { + .open = tracing_err_log_open, + .write = tracing_err_log_write, + .read = seq_read, + .llseek = tracing_lseek, + .release = tracing_err_log_release, +}; + static int tracing_buffers_open(struct inode *inode, struct file *filp) { struct trace_array *tr = inode->i_private; struct ftrace_buffer_info *info; int ret; - if (tracing_disabled) - return -ENODEV; + ret = tracing_check_open_get_tr(tr); + if (ret) + return ret; - if (trace_array_get(tr) < 0) - return -ENODEV; - - info = kzalloc(sizeof(*info), GFP_KERNEL); + info = kvzalloc(sizeof(*info), GFP_KERNEL); if (!info) { trace_array_put(tr); return -ENOMEM; @@ -6720,14 +7605,14 @@ info->iter.tr = tr; info->iter.cpu_file = tracing_get_cpu(inode); info->iter.trace = tr->current_trace; - info->iter.trace_buffer = &tr->trace_buffer; + info->iter.array_buffer = &tr->array_buffer; info->spare = NULL; /* Force reading ring buffer for first read */ info->read = (unsigned int)-1; filp->private_data = info; - tr->current_trace->ref++; + tr->trace_ref++; mutex_unlock(&trace_types_lock); @@ -6765,7 +7650,7 @@ #endif if (!info->spare) { - info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer, + info->spare = ring_buffer_alloc_read_page(iter->array_buffer->buffer, iter->cpu_file); if (IS_ERR(info->spare)) { ret = PTR_ERR(info->spare); @@ -6783,7 +7668,7 @@ again: trace_access_lock(iter->cpu_file); - ret = ring_buffer_read_page(iter->trace_buffer->buffer, + ret = ring_buffer_read_page(iter->array_buffer->buffer, &info->spare, count, iter->cpu_file, 0); @@ -6794,7 +7679,7 @@ if ((filp->f_flags & O_NONBLOCK)) return -EAGAIN; - ret = wait_on_pipe(iter, false); + ret = wait_on_pipe(iter, 0); if (ret) return ret; @@ -6828,14 +7713,14 @@ mutex_lock(&trace_types_lock); - iter->tr->current_trace->ref--; + iter->tr->trace_ref--; __trace_array_put(iter->tr); if (info->spare) - ring_buffer_free_read_page(iter->trace_buffer->buffer, + ring_buffer_free_read_page(iter->array_buffer->buffer, info->spare_cpu, info->spare); - kfree(info); + kvfree(info); mutex_unlock(&trace_types_lock); @@ -6843,7 +7728,7 @@ } struct buffer_ref { - struct ring_buffer *buffer; + struct trace_buffer *buffer; void *page; int cpu; refcount_t refcount; @@ -6880,10 +7765,7 @@ /* Pipe buffer operations for a buffer. */ static const struct pipe_buf_operations buffer_pipe_buf_ops = { - .can_merge = 0, - .confirm = generic_pipe_buf_confirm, .release = buffer_pipe_buf_release, - .steal = generic_pipe_buf_nosteal, .get = buffer_pipe_buf_get, }; @@ -6939,7 +7821,7 @@ again: trace_access_lock(iter->cpu_file); - entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); + entries = ring_buffer_entries_cpu(iter->array_buffer->buffer, iter->cpu_file); for (i = 0; i < spd.nr_pages_max && len && entries; i++, len -= PAGE_SIZE) { struct page *page; @@ -6952,7 +7834,7 @@ } refcount_set(&ref->refcount, 1); - ref->buffer = iter->trace_buffer->buffer; + ref->buffer = iter->array_buffer->buffer; ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); if (IS_ERR(ref->page)) { ret = PTR_ERR(ref->page); @@ -6980,7 +7862,7 @@ spd.nr_pages++; *ppos += PAGE_SIZE; - entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); + entries = ring_buffer_entries_cpu(iter->array_buffer->buffer, iter->cpu_file); } trace_access_unlock(iter->cpu_file); @@ -6995,7 +7877,7 @@ if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) goto out; - ret = wait_on_pipe(iter, true); + ret = wait_on_pipe(iter, iter->tr->buffer_percent); if (ret) goto out; @@ -7024,7 +7906,7 @@ { struct inode *inode = file_inode(filp); struct trace_array *tr = inode->i_private; - struct trace_buffer *trace_buf = &tr->trace_buffer; + struct array_buffer *trace_buf = &tr->array_buffer; int cpu = tracing_get_cpu(inode); struct trace_seq *s; unsigned long cnt; @@ -7095,14 +7977,23 @@ tracing_read_dyn_info(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { - unsigned long *p = filp->private_data; - char buf[64]; /* Not too big for a shallow stack */ + ssize_t ret; + char *buf; int r; - r = scnprintf(buf, 63, "%ld", *p); - buf[r++] = '\n'; + /* 256 should be plenty to hold the amount needed */ + buf = kmalloc(256, GFP_KERNEL); + if (!buf) + return -ENOMEM; - return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); + r = scnprintf(buf, 256, "%ld pages:%ld groups: %ld\n", + ftrace_update_tot_cnt, + ftrace_number_of_pages, + ftrace_number_of_groups); + + ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); + kfree(buf); + return ret; } static const struct file_operations tracing_dyn_info_fops = { @@ -7296,7 +8187,7 @@ tr->percpu_dir = tracefs_create_dir("per_cpu", d_tracer); - WARN_ONCE(!tr->percpu_dir, + MEM_FAIL(!tr->percpu_dir, "Could not create tracefs directory 'per_cpu/%d'\n", cpu); return tr->percpu_dir; @@ -7405,12 +8296,33 @@ return cnt; } +static int tracing_open_options(struct inode *inode, struct file *filp) +{ + struct trace_option_dentry *topt = inode->i_private; + int ret; + + ret = tracing_check_open_get_tr(topt->tr); + if (ret) + return ret; + + filp->private_data = inode->i_private; + return 0; +} + +static int tracing_release_options(struct inode *inode, struct file *file) +{ + struct trace_option_dentry *topt = file->private_data; + + trace_array_put(topt->tr); + return 0; +} static const struct file_operations trace_options_fops = { - .open = tracing_open_generic, + .open = tracing_open_options, .read = trace_options_read, .write = trace_options_write, .llseek = generic_file_llseek, + .release = tracing_release_options, }; /* @@ -7617,7 +8529,7 @@ for (cnt = 0; opts[cnt].name; cnt++) { create_trace_option_file(tr, &topts[cnt], flags, &opts[cnt]); - WARN_ONCE(topts[cnt].entry == NULL, + MEM_FAIL(topts[cnt].entry == NULL, "Failed to create trace option: %s", opts[cnt].name); } @@ -7674,7 +8586,7 @@ size_t cnt, loff_t *ppos) { struct trace_array *tr = filp->private_data; - struct ring_buffer *buffer = tr->trace_buffer.buffer; + struct trace_buffer *buffer = tr->array_buffer.buffer; unsigned long val; int ret; @@ -7711,13 +8623,57 @@ .llseek = default_llseek, }; -struct dentry *trace_instance_dir; +static ssize_t +buffer_percent_read(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + struct trace_array *tr = filp->private_data; + char buf[64]; + int r; + + r = tr->buffer_percent; + r = sprintf(buf, "%d\n", r); + + return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); +} + +static ssize_t +buffer_percent_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + struct trace_array *tr = filp->private_data; + unsigned long val; + int ret; + + ret = kstrtoul_from_user(ubuf, cnt, 10, &val); + if (ret) + return ret; + + if (val > 100) + return -EINVAL; + + tr->buffer_percent = val; + + (*ppos)++; + + return cnt; +} + +static const struct file_operations buffer_percent_fops = { + .open = tracing_open_generic_tr, + .read = buffer_percent_read, + .write = buffer_percent_write, + .release = tracing_release_generic_tr, + .llseek = default_llseek, +}; + +static struct dentry *trace_instance_dir; static void init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer); static int -allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size) +allocate_trace_buffer(struct trace_array *tr, struct array_buffer *buf, int size) { enum ring_buffer_flags rb_flags; @@ -7737,8 +8693,8 @@ } /* Allocate the first page for all buffers */ - set_buffer_entries(&tr->trace_buffer, - ring_buffer_size(tr->trace_buffer.buffer, 0)); + set_buffer_entries(&tr->array_buffer, + ring_buffer_size(tr->array_buffer.buffer, 0)); return 0; } @@ -7747,18 +8703,18 @@ { int ret; - ret = allocate_trace_buffer(tr, &tr->trace_buffer, size); + ret = allocate_trace_buffer(tr, &tr->array_buffer, size); if (ret) return ret; #ifdef CONFIG_TRACER_MAX_TRACE ret = allocate_trace_buffer(tr, &tr->max_buffer, allocate_snapshot ? size : 1); - if (WARN_ON(ret)) { - ring_buffer_free(tr->trace_buffer.buffer); - tr->trace_buffer.buffer = NULL; - free_percpu(tr->trace_buffer.data); - tr->trace_buffer.data = NULL; + if (MEM_FAIL(ret, "Failed to allocate trace buffer\n")) { + ring_buffer_free(tr->array_buffer.buffer); + tr->array_buffer.buffer = NULL; + free_percpu(tr->array_buffer.data); + tr->array_buffer.data = NULL; return -ENOMEM; } tr->allocated_snapshot = allocate_snapshot; @@ -7770,22 +8726,10 @@ allocate_snapshot = false; #endif - /* - * Because of some magic with the way alloc_percpu() works on - * x86_64, we need to synchronize the pgd of all the tables, - * otherwise the trace events that happen in x86_64 page fault - * handlers can't cope with accessing the chance that a - * alloc_percpu()'d memory might be touched in the page fault trace - * event. Oh, and we need to audit all other alloc_percpu() and vmalloc() - * calls in tracing, because something might get triggered within a - * page fault trace event! - */ - vmalloc_sync_mappings(); - return 0; } -static void free_trace_buffer(struct trace_buffer *buf) +static void free_trace_buffer(struct array_buffer *buf) { if (buf->buffer) { ring_buffer_free(buf->buffer); @@ -7800,7 +8744,7 @@ if (!tr) return; - free_trace_buffer(&tr->trace_buffer); + free_trace_buffer(&tr->array_buffer); #ifdef CONFIG_TRACER_MAX_TRACE free_trace_buffer(&tr->max_buffer); @@ -7827,28 +8771,68 @@ static void update_tracer_options(struct trace_array *tr) { mutex_lock(&trace_types_lock); + tracer_options_updated = true; __update_tracer_options(tr); mutex_unlock(&trace_types_lock); } -static int instance_mkdir(const char *name) +/* Must have trace_types_lock held */ +struct trace_array *trace_array_find(const char *instance) +{ + struct trace_array *tr, *found = NULL; + + list_for_each_entry(tr, &ftrace_trace_arrays, list) { + if (tr->name && strcmp(tr->name, instance) == 0) { + found = tr; + break; + } + } + + return found; +} + +struct trace_array *trace_array_find_get(const char *instance) +{ + struct trace_array *tr; + + mutex_lock(&trace_types_lock); + tr = trace_array_find(instance); + if (tr) + tr->ref++; + mutex_unlock(&trace_types_lock); + + return tr; +} + +static int trace_array_create_dir(struct trace_array *tr) +{ + int ret; + + tr->dir = tracefs_create_dir(tr->name, trace_instance_dir); + if (!tr->dir) + return -EINVAL; + + ret = event_trace_add_tracer(tr->dir, tr); + if (ret) { + tracefs_remove(tr->dir); + return ret; + } + + init_tracer_tracefs(tr, tr->dir); + __update_tracer_options(tr); + + return ret; +} + +static struct trace_array *trace_array_create(const char *name) { struct trace_array *tr; int ret; - mutex_lock(&event_mutex); - mutex_lock(&trace_types_lock); - - ret = -EEXIST; - list_for_each_entry(tr, &ftrace_trace_arrays, list) { - if (tr->name && strcmp(tr->name, name) == 0) - goto out_unlock; - } - ret = -ENOMEM; tr = kzalloc(sizeof(*tr), GFP_KERNEL); if (!tr) - goto out_unlock; + return ERR_PTR(ret); tr->name = kstrdup(name, GFP_KERNEL); if (!tr->name) @@ -7870,70 +8854,112 @@ INIT_LIST_HEAD(&tr->systems); INIT_LIST_HEAD(&tr->events); INIT_LIST_HEAD(&tr->hist_vars); + INIT_LIST_HEAD(&tr->err_log); if (allocate_trace_buffers(tr, trace_buf_size) < 0) goto out_free_tr; - tr->dir = tracefs_create_dir(name, trace_instance_dir); - if (!tr->dir) + if (ftrace_allocate_ftrace_ops(tr) < 0) goto out_free_tr; - - ret = event_trace_add_tracer(tr->dir, tr); - if (ret) { - tracefs_remove_recursive(tr->dir); - goto out_free_tr; - } ftrace_init_trace_array(tr); - init_tracer_tracefs(tr, tr->dir); init_trace_flags_index(tr); - __update_tracer_options(tr); + + if (trace_instance_dir) { + ret = trace_array_create_dir(tr); + if (ret) + goto out_free_tr; + } else + __trace_early_add_events(tr); list_add(&tr->list, &ftrace_trace_arrays); - mutex_unlock(&trace_types_lock); - mutex_unlock(&event_mutex); + tr->ref++; - return 0; + return tr; out_free_tr: + ftrace_free_ftrace_ops(tr); free_trace_buffers(tr); free_cpumask_var(tr->tracing_cpumask); kfree(tr->name); kfree(tr); - out_unlock: - mutex_unlock(&trace_types_lock); - mutex_unlock(&event_mutex); - - return ret; - + return ERR_PTR(ret); } -static int instance_rmdir(const char *name) +static int instance_mkdir(const char *name) { struct trace_array *tr; - int found = 0; int ret; - int i; mutex_lock(&event_mutex); mutex_lock(&trace_types_lock); - ret = -ENODEV; - list_for_each_entry(tr, &ftrace_trace_arrays, list) { - if (tr->name && strcmp(tr->name, name) == 0) { - found = 1; - break; - } - } - if (!found) + ret = -EEXIST; + if (trace_array_find(name)) goto out_unlock; - ret = -EBUSY; - if (tr->ref || (tr->current_trace && tr->current_trace->ref)) - goto out_unlock; + tr = trace_array_create(name); + + ret = PTR_ERR_OR_ZERO(tr); + +out_unlock: + mutex_unlock(&trace_types_lock); + mutex_unlock(&event_mutex); + return ret; +} + +/** + * trace_array_get_by_name - Create/Lookup a trace array, given its name. + * @name: The name of the trace array to be looked up/created. + * + * Returns pointer to trace array with given name. + * NULL, if it cannot be created. + * + * NOTE: This function increments the reference counter associated with the + * trace array returned. This makes sure it cannot be freed while in use. + * Use trace_array_put() once the trace array is no longer needed. + * If the trace_array is to be freed, trace_array_destroy() needs to + * be called after the trace_array_put(), or simply let user space delete + * it from the tracefs instances directory. But until the + * trace_array_put() is called, user space can not delete it. + * + */ +struct trace_array *trace_array_get_by_name(const char *name) +{ + struct trace_array *tr; + + mutex_lock(&event_mutex); + mutex_lock(&trace_types_lock); + + list_for_each_entry(tr, &ftrace_trace_arrays, list) { + if (tr->name && strcmp(tr->name, name) == 0) + goto out_unlock; + } + + tr = trace_array_create(name); + + if (IS_ERR(tr)) + tr = NULL; +out_unlock: + if (tr) + tr->ref++; + + mutex_unlock(&trace_types_lock); + mutex_unlock(&event_mutex); + return tr; +} +EXPORT_SYMBOL_GPL(trace_array_get_by_name); + +static int __remove_instance(struct trace_array *tr) +{ + int i; + + /* Reference counter for a newly created trace array = 1. */ + if (tr->ref > 1 || (tr->current_trace && tr->trace_ref)) + return -EBUSY; list_del(&tr->list); @@ -7948,8 +8974,9 @@ event_trace_del_tracer(tr); ftrace_clear_pids(tr); ftrace_destroy_function_files(tr); - tracefs_remove_recursive(tr->dir); + tracefs_remove(tr->dir); free_trace_buffers(tr); + clear_tracing_err_log(tr); for (i = 0; i < tr->nr_topts; i++) { kfree(tr->topts[i].topts); @@ -7960,9 +8987,50 @@ kfree(tr->name); kfree(tr); - ret = 0; + return 0; +} - out_unlock: +int trace_array_destroy(struct trace_array *this_tr) +{ + struct trace_array *tr; + int ret; + + if (!this_tr) + return -EINVAL; + + mutex_lock(&event_mutex); + mutex_lock(&trace_types_lock); + + ret = -ENODEV; + + /* Making sure trace array exists before destroying it. */ + list_for_each_entry(tr, &ftrace_trace_arrays, list) { + if (tr == this_tr) { + ret = __remove_instance(tr); + break; + } + } + + mutex_unlock(&trace_types_lock); + mutex_unlock(&event_mutex); + + return ret; +} +EXPORT_SYMBOL_GPL(trace_array_destroy); + +static int instance_rmdir(const char *name) +{ + struct trace_array *tr; + int ret; + + mutex_lock(&event_mutex); + mutex_lock(&trace_types_lock); + + ret = -ENODEV; + tr = trace_array_find(name); + if (tr) + ret = __remove_instance(tr); + mutex_unlock(&trace_types_lock); mutex_unlock(&event_mutex); @@ -7971,11 +9039,27 @@ static __init void create_trace_instances(struct dentry *d_tracer) { + struct trace_array *tr; + trace_instance_dir = tracefs_create_instance_dir("instances", d_tracer, instance_mkdir, instance_rmdir); - if (WARN_ON(!trace_instance_dir)) + if (MEM_FAIL(!trace_instance_dir, "Failed to create instances directory\n")) return; + + mutex_lock(&event_mutex); + mutex_lock(&trace_types_lock); + + list_for_each_entry(tr, &ftrace_trace_arrays, list) { + if (!tr->name) + continue; + if (MEM_FAIL(trace_array_create_dir(tr) < 0, + "Failed to create instance directory\n")) + break; + } + + mutex_unlock(&trace_types_lock); + mutex_unlock(&event_mutex); } static void @@ -8032,20 +9116,27 @@ trace_create_file("timestamp_mode", 0444, d_tracer, tr, &trace_time_stamp_mode_fops); + tr->buffer_percent = 50; + + trace_create_file("buffer_percent", 0444, d_tracer, + tr, &buffer_percent_fops); + create_trace_options_dir(tr); #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) - trace_create_file("tracing_max_latency", 0644, d_tracer, - &tr->max_latency, &tracing_max_lat_fops); + trace_create_maxlat_file(tr, d_tracer); #endif if (ftrace_create_function_files(tr, d_tracer)) - WARN(1, "Could not allocate function filter files"); + MEM_FAIL(1, "Could not allocate function filter files"); #ifdef CONFIG_TRACER_SNAPSHOT trace_create_file("snapshot", 0644, d_tracer, tr, &snapshot_fops); #endif + + trace_create_file("error_log", 0644, d_tracer, + tr, &tracing_err_log_fops); for_each_tracing_cpu(cpu) tracing_init_tracefs_percpu(tr, cpu); @@ -8053,6 +9144,7 @@ ftrace_init_tracefs(tr, d_tracer); } +#ifndef CONFIG_TRACEFS_DISABLE_AUTOMOUNT static struct vfsmount *trace_automount(struct dentry *mntpt, void *ingore) { struct vfsmount *mnt; @@ -8074,6 +9166,7 @@ return mnt; } +#endif /** * tracing_init_dentry - initialize top level trace array @@ -8082,19 +9175,23 @@ * directory. It is called via fs_initcall() by any of the boot up code * and expects to return the dentry of the top level tracing directory. */ -struct dentry *tracing_init_dentry(void) +int tracing_init_dentry(void) { struct trace_array *tr = &global_trace; + if (security_locked_down(LOCKDOWN_TRACEFS)) { + pr_warn("Tracing disabled due to lockdown\n"); + return -EPERM; + } + /* The top level trace array uses NULL as parent */ if (tr->dir) - return NULL; + return 0; - if (WARN_ON(!tracefs_initialized()) || - (IS_ENABLED(CONFIG_DEBUG_FS) && - WARN_ON(!debugfs_initialized()))) - return ERR_PTR(-ENODEV); + if (WARN_ON(!tracefs_initialized())) + return -ENODEV; +#ifndef CONFIG_TRACEFS_DISABLE_AUTOMOUNT /* * As there may still be users that expect the tracing * files to exist in debugfs/tracing, we must automount @@ -8103,12 +9200,11 @@ */ tr->dir = debugfs_create_automount("tracing", NULL, trace_automount, NULL); - if (!tr->dir) { - pr_warn_once("Could not create debugfs directory 'tracing'\n"); - return ERR_PTR(-ENOMEM); - } +#else + tr->dir = ERR_PTR(-ENODEV); +#endif - return NULL; + return 0; } extern struct trace_eval_map *__start_ftrace_eval_maps[]; @@ -8184,7 +9280,7 @@ break; } - return 0; + return NOTIFY_OK; } static struct notifier_block trace_module_nb = { @@ -8195,48 +9291,48 @@ static __init int tracer_init_tracefs(void) { - struct dentry *d_tracer; + int ret; trace_access_lock_init(); - d_tracer = tracing_init_dentry(); - if (IS_ERR(d_tracer)) + ret = tracing_init_dentry(); + if (ret) return 0; event_trace_init(); - init_tracer_tracefs(&global_trace, d_tracer); - ftrace_init_tracefs_toplevel(&global_trace, d_tracer); + init_tracer_tracefs(&global_trace, NULL); + ftrace_init_tracefs_toplevel(&global_trace, NULL); - trace_create_file("tracing_thresh", 0644, d_tracer, + trace_create_file("tracing_thresh", 0644, NULL, &global_trace, &tracing_thresh_fops); - trace_create_file("README", 0444, d_tracer, + trace_create_file("README", 0444, NULL, NULL, &tracing_readme_fops); - trace_create_file("saved_cmdlines", 0444, d_tracer, + trace_create_file("saved_cmdlines", 0444, NULL, NULL, &tracing_saved_cmdlines_fops); - trace_create_file("saved_cmdlines_size", 0644, d_tracer, + trace_create_file("saved_cmdlines_size", 0644, NULL, NULL, &tracing_saved_cmdlines_size_fops); - trace_create_file("saved_tgids", 0444, d_tracer, + trace_create_file("saved_tgids", 0444, NULL, NULL, &tracing_saved_tgids_fops); trace_eval_init(); - trace_create_eval_file(d_tracer); + trace_create_eval_file(NULL); #ifdef CONFIG_MODULES register_module_notifier(&trace_module_nb); #endif #ifdef CONFIG_DYNAMIC_FTRACE - trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, - &ftrace_update_tot_cnt, &tracing_dyn_info_fops); + trace_create_file("dyn_ftrace_total_info", 0444, NULL, + NULL, &tracing_dyn_info_fops); #endif - create_trace_instances(d_tracer); + create_trace_instances(NULL); update_tracer_options(&global_trace); @@ -8246,8 +9342,17 @@ static int trace_panic_handler(struct notifier_block *this, unsigned long event, void *unused) { + bool ftrace_check = false; + + trace_android_vh_ftrace_oops_enter(&ftrace_check); + + if (ftrace_check) + return NOTIFY_OK; + if (ftrace_dump_on_oops) ftrace_dump(ftrace_dump_on_oops); + + trace_android_vh_ftrace_oops_exit(&ftrace_check); return NOTIFY_OK; } @@ -8261,6 +9366,13 @@ unsigned long val, void *data) { + bool ftrace_check = false; + + trace_android_vh_ftrace_oops_enter(&ftrace_check); + + if (ftrace_check) + return NOTIFY_OK; + switch (val) { case DIE_OOPS: if (ftrace_dump_on_oops) @@ -8269,6 +9381,8 @@ default: break; } + + trace_android_vh_ftrace_oops_exit(&ftrace_check); return NOTIFY_OK; } @@ -8293,6 +9407,8 @@ void trace_printk_seq(struct trace_seq *s) { + bool dump_printk = true; + /* Probably should print a warning here. */ if (s->seq.len >= TRACE_MAX_PRINT) s->seq.len = TRACE_MAX_PRINT; @@ -8308,7 +9424,9 @@ /* should be zero ended, but we are paranoid. */ s->buffer[s->seq.len] = 0; - printk(KERN_TRACE "%s", s->buffer); + trace_android_vh_ftrace_dump_buffer(s, &dump_printk); + if (dump_printk) + printk(KERN_TRACE "%s", s->buffer); trace_seq_init(s); } @@ -8318,13 +9436,13 @@ iter->tr = &global_trace; iter->trace = iter->tr->current_trace; iter->cpu_file = RING_BUFFER_ALL_CPUS; - iter->trace_buffer = &global_trace.trace_buffer; + iter->array_buffer = &global_trace.array_buffer; if (iter->trace && iter->trace->open) iter->trace->open(iter); /* Annotate start of buffers if we had overruns */ - if (ring_buffer_overruns(iter->trace_buffer->buffer)) + if (ring_buffer_overruns(iter->array_buffer->buffer)) iter->iter_flags |= TRACE_FILE_ANNOTATE; /* Output in nanoseconds only if we are using a clock in nanoseconds. */ @@ -8341,6 +9459,8 @@ unsigned int old_userobj; unsigned long flags; int cnt = 0, cpu; + bool ftrace_check = false; + unsigned long size; /* Only allow one dump user at a time. */ if (atomic_inc_return(&dump_running) != 1) { @@ -8363,15 +9483,23 @@ /* Simulate the iterator */ trace_init_global_iter(&iter); + /* Can not use kmalloc for iter.temp */ + iter.temp = static_temp_buf; + iter.temp_size = STATIC_TEMP_BUF_SIZE; for_each_tracing_cpu(cpu) { - atomic_inc(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); + atomic_inc(&per_cpu_ptr(iter.array_buffer->data, cpu)->disabled); + size = ring_buffer_size(iter.array_buffer->buffer, cpu); + trace_android_vh_ftrace_size_check(size, &ftrace_check); } old_userobj = tr->trace_flags & TRACE_ITER_SYM_USEROBJ; /* don't look at user memory in panic mode */ tr->trace_flags &= ~TRACE_ITER_SYM_USEROBJ; + + if (ftrace_check) + goto out_enable; switch (oops_dump_mode) { case DUMP_ALL: @@ -8396,13 +9524,14 @@ } /* - * We need to stop all tracing on all CPUS to read the + * We need to stop all tracing on all CPUS to read * the next buffer. This is a bit expensive, but is * not done often. We fill all what we can read, * and then release the locks again. */ while (!trace_empty(&iter)) { + ftrace_check = true; if (!cnt) printk(KERN_TRACE "---------------------------------\n"); @@ -8410,7 +9539,9 @@ cnt++; trace_iterator_reset(&iter); - iter.iter_flags |= TRACE_FILE_LAT_FMT; + trace_android_vh_ftrace_format_check(&ftrace_check); + if (ftrace_check) + iter.iter_flags |= TRACE_FILE_LAT_FMT; if (trace_find_next_entry_inc(&iter) != NULL) { int ret; @@ -8433,7 +9564,7 @@ tr->trace_flags |= old_userobj; for_each_tracing_cpu(cpu) { - atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); + atomic_dec(&per_cpu_ptr(iter.array_buffer->data, cpu)->disabled); } atomic_dec(&dump_running); printk_nmi_direct_exit(); @@ -8532,8 +9663,14 @@ int ring_buf_size; int ret = -ENOMEM; + + if (security_locked_down(LOCKDOWN_TRACEFS)) { + pr_warn("Tracing disabled due to lockdown\n"); + return -EPERM; + } + /* - * Make sure we don't accidently add more trace options + * Make sure we don't accidentally add more trace options * than we have bits for. */ BUILD_BUG_ON(TRACE_ITER_LAST_BIT > TRACE_FLAGS_MAX_SIZE); @@ -8562,7 +9699,7 @@ /* * The prepare callbacks allocates some memory for the ring buffer. We - * don't free the buffer if the if the CPU goes down. If we were to free + * don't free the buffer if the CPU goes down. If we were to free * the buffer, then the user would lose any trace that was in the * buffer. The memory will be removed once the "instance" is removed. */ @@ -8582,8 +9719,7 @@ /* TODO: make the number of buffers hot pluggable with CPUS */ if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { - printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); - WARN_ON(1); + MEM_FAIL(1, "tracer: failed to allocate ring buffer!\n"); goto out_free_savedcmd; } @@ -8628,6 +9764,7 @@ INIT_LIST_HEAD(&global_trace.systems); INIT_LIST_HEAD(&global_trace.events); INIT_LIST_HEAD(&global_trace.hist_vars); + INIT_LIST_HEAD(&global_trace.err_log); list_add(&global_trace.list, &ftrace_trace_arrays); apply_trace_boot_options(); @@ -8655,12 +9792,15 @@ if (tracepoint_printk) { tracepoint_print_iter = kmalloc(sizeof(*tracepoint_print_iter), GFP_KERNEL); - if (WARN_ON(!tracepoint_print_iter)) + if (MEM_FAIL(!tracepoint_print_iter, + "Failed to allocate trace iterator\n")) tracepoint_printk = 0; else static_key_enable(&tracepoint_printk_key.key); } tracer_alloc_buffers(); + + init_events(); } void __init trace_init(void) @@ -8695,6 +9835,11 @@ { /* sched_clock_stable() is determined in late_initcall */ if (!trace_boot_clock && !sched_clock_stable()) { + if (security_locked_down(LOCKDOWN_TRACEFS)) { + pr_warn("Can not set tracing clock due to lockdown\n"); + return -EPERM; + } + printk(KERN_WARNING "Unstable clock detected, switching default tracing clock to \"global\"\n" "If you want to keep using the local clock, then add:\n" -- Gitblit v1.6.2