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/ftrace.c | 1787 ++++++++++++++++++++++++++++++++++++++---------------------
1 files changed, 1,140 insertions(+), 647 deletions(-)
diff --git a/kernel/kernel/trace/ftrace.c b/kernel/kernel/trace/ftrace.c
index 35f8765..31fec92 100644
--- a/kernel/kernel/trace/ftrace.c
+++ b/kernel/kernel/trace/ftrace.c
@@ -18,8 +18,8 @@
#include <linux/clocksource.h>
#include <linux/sched/task.h>
#include <linux/kallsyms.h>
+#include <linux/security.h>
#include <linux/seq_file.h>
-#include <linux/suspend.h>
#include <linux/tracefs.h>
#include <linux/hardirq.h>
#include <linux/kthread.h>
@@ -41,6 +41,7 @@
#include <asm/sections.h>
#include <asm/setup.h>
+#include "ftrace_internal.h"
#include "trace_output.h"
#include "trace_stat.h"
@@ -61,8 +62,6 @@
})
/* hash bits for specific function selection */
-#define FTRACE_HASH_BITS 7
-#define FTRACE_FUNC_HASHSIZE (1 << FTRACE_HASH_BITS)
#define FTRACE_HASH_DEFAULT_BITS 10
#define FTRACE_HASH_MAX_BITS 12
@@ -70,15 +69,16 @@
#define INIT_OPS_HASH(opsname) \
.func_hash = &opsname.local_hash, \
.local_hash.regex_lock = __MUTEX_INITIALIZER(opsname.local_hash.regex_lock),
-#define ASSIGN_OPS_HASH(opsname, val) \
- .func_hash = val, \
- .local_hash.regex_lock = __MUTEX_INITIALIZER(opsname.local_hash.regex_lock),
#else
#define INIT_OPS_HASH(opsname)
-#define ASSIGN_OPS_HASH(opsname, val)
#endif
-static struct ftrace_ops ftrace_list_end __read_mostly = {
+enum {
+ FTRACE_MODIFY_ENABLE_FL = (1 << 0),
+ FTRACE_MODIFY_MAY_SLEEP_FL = (1 << 1),
+};
+
+struct ftrace_ops ftrace_list_end __read_mostly = {
.func = ftrace_stub,
.flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_STUB,
INIT_OPS_HASH(ftrace_list_end)
@@ -102,7 +102,7 @@
tr = ops->private;
- return tr->function_pids != NULL;
+ return tr->function_pids != NULL || tr->function_no_pids != NULL;
}
static void ftrace_update_trampoline(struct ftrace_ops *ops);
@@ -113,41 +113,20 @@
*/
static int ftrace_disabled __read_mostly;
-static DEFINE_MUTEX(ftrace_lock);
+DEFINE_MUTEX(ftrace_lock);
-static struct ftrace_ops __rcu *ftrace_ops_list __read_mostly = &ftrace_list_end;
+struct ftrace_ops __rcu *ftrace_ops_list __read_mostly = &ftrace_list_end;
ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub;
-static struct ftrace_ops global_ops;
+struct ftrace_ops global_ops;
#if ARCH_SUPPORTS_FTRACE_OPS
static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct pt_regs *regs);
#else
/* See comment below, where ftrace_ops_list_func is defined */
-static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip,
- struct ftrace_ops *op, struct pt_regs *regs);
-#define ftrace_ops_list_func ftrace_ops_no_ops
+static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip);
+#define ftrace_ops_list_func ((ftrace_func_t)ftrace_ops_no_ops)
#endif
-
-/*
- * Traverse the ftrace_global_list, invoking all entries. The reason that we
- * can use rcu_dereference_raw_notrace() is that elements removed from this list
- * are simply leaked, so there is no need to interact with a grace-period
- * mechanism. The rcu_dereference_raw_notrace() calls are needed to handle
- * concurrent insertions into the ftrace_global_list.
- *
- * Silly Alpha and silly pointer-speculation compiler optimizations!
- */
-#define do_for_each_ftrace_op(op, list) \
- op = rcu_dereference_raw_notrace(list); \
- do
-
-/*
- * Optimized for just a single item in the list (as that is the normal case).
- */
-#define while_for_each_ftrace_op(op) \
- while (likely(op = rcu_dereference_raw_notrace((op)->next)) && \
- unlikely((op) != &ftrace_list_end))
static inline void ftrace_ops_init(struct ftrace_ops *ops)
{
@@ -164,22 +143,18 @@
struct ftrace_ops *op, struct pt_regs *regs)
{
struct trace_array *tr = op->private;
+ int pid;
- if (tr && this_cpu_read(tr->trace_buffer.data->ftrace_ignore_pid))
- return;
+ if (tr) {
+ pid = this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid);
+ if (pid == FTRACE_PID_IGNORE)
+ return;
+ if (pid != FTRACE_PID_TRACE &&
+ pid != current->pid)
+ return;
+ }
op->saved_func(ip, parent_ip, op, regs);
-}
-
-static void ftrace_sync(struct work_struct *work)
-{
- /*
- * This function is just a stub to implement a hard force
- * of synchronize_sched(). This requires synchronizing
- * tasks even in userspace and idle.
- *
- * Yes, function tracing is rude.
- */
}
static void ftrace_sync_ipi(void *data)
@@ -187,18 +162,6 @@
/* Probably not needed, but do it anyway */
smp_rmb();
}
-
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-static void update_function_graph_func(void);
-
-/* Both enabled by default (can be cleared by function_graph tracer flags */
-static bool fgraph_sleep_time = true;
-static bool fgraph_graph_time = true;
-
-#else
-static inline void update_function_graph_func(void) { }
-#endif
-
static ftrace_func_t ftrace_ops_get_list_func(struct ftrace_ops *ops)
{
@@ -267,7 +230,7 @@
/*
* For static tracing, we need to be a bit more careful.
* The function change takes affect immediately. Thus,
- * we need to coorditate the setting of the function_trace_ops
+ * we need to coordinate the setting of the function_trace_ops
* with the setting of the ftrace_trace_function.
*
* Set the function to the list ops, which will call the
@@ -279,7 +242,7 @@
* Make sure all CPUs see this. Yes this is slow, but static
* tracing is slow and nasty to have enabled.
*/
- schedule_on_each_cpu(ftrace_sync);
+ synchronize_rcu_tasks_rude();
/* Now all cpus are using the list ops. */
function_trace_op = set_function_trace_op;
/* Make sure the function_trace_op is visible on all CPUs */
@@ -336,7 +299,7 @@
static void ftrace_update_trampoline(struct ftrace_ops *ops);
-static int __register_ftrace_function(struct ftrace_ops *ops)
+int __register_ftrace_function(struct ftrace_ops *ops)
{
if (ops->flags & FTRACE_OPS_FL_DELETED)
return -EINVAL;
@@ -357,6 +320,8 @@
if (ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED)
ops->flags |= FTRACE_OPS_FL_SAVE_REGS;
#endif
+ if (!ftrace_enabled && (ops->flags & FTRACE_OPS_FL_PERMANENT))
+ return -EBUSY;
if (!core_kernel_data((unsigned long)ops))
ops->flags |= FTRACE_OPS_FL_DYNAMIC;
@@ -377,7 +342,7 @@
return 0;
}
-static int __unregister_ftrace_function(struct ftrace_ops *ops)
+int __unregister_ftrace_function(struct ftrace_ops *ops)
{
int ret;
@@ -494,10 +459,10 @@
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
/* function graph compares on total time */
-static int function_stat_cmp(void *p1, void *p2)
+static int function_stat_cmp(const void *p1, const void *p2)
{
- struct ftrace_profile *a = p1;
- struct ftrace_profile *b = p2;
+ const struct ftrace_profile *a = p1;
+ const struct ftrace_profile *b = p2;
if (a->time < b->time)
return -1;
@@ -508,10 +473,10 @@
}
#else
/* not function graph compares against hits */
-static int function_stat_cmp(void *p1, void *p2)
+static int function_stat_cmp(const void *p1, const void *p2)
{
- struct ftrace_profile *a = p1;
- struct ftrace_profile *b = p2;
+ const struct ftrace_profile *a = p1;
+ const struct ftrace_profile *b = p2;
if (a->counter < b->counter)
return -1;
@@ -817,9 +782,16 @@
}
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+static bool fgraph_graph_time = true;
+
+void ftrace_graph_graph_time_control(bool enable)
+{
+ fgraph_graph_time = enable;
+}
+
static int profile_graph_entry(struct ftrace_graph_ent *trace)
{
- int index = current->curr_ret_stack;
+ struct ftrace_ret_stack *ret_stack;
function_profile_call(trace->func, 0, NULL, NULL);
@@ -827,14 +799,16 @@
if (!current->ret_stack)
return 0;
- if (index >= 0 && index < FTRACE_RETFUNC_DEPTH)
- current->ret_stack[index].subtime = 0;
+ ret_stack = ftrace_graph_get_ret_stack(current, 0);
+ if (ret_stack)
+ ret_stack->subtime = 0;
return 1;
}
static void profile_graph_return(struct ftrace_graph_ret *trace)
{
+ struct ftrace_ret_stack *ret_stack;
struct ftrace_profile_stat *stat;
unsigned long long calltime;
struct ftrace_profile *rec;
@@ -852,16 +826,15 @@
calltime = trace->rettime - trace->calltime;
if (!fgraph_graph_time) {
- int index;
-
- index = current->curr_ret_stack;
/* Append this call time to the parent time to subtract */
- if (index)
- current->ret_stack[index - 1].subtime += calltime;
+ ret_stack = ftrace_graph_get_ret_stack(current, 1);
+ if (ret_stack)
+ ret_stack->subtime += calltime;
- if (current->ret_stack[index].subtime < calltime)
- calltime -= current->ret_stack[index].subtime;
+ ret_stack = ftrace_graph_get_ret_stack(current, 0);
+ if (ret_stack && ret_stack->subtime < calltime)
+ calltime -= ret_stack->subtime;
else
calltime = 0;
}
@@ -876,15 +849,19 @@
local_irq_restore(flags);
}
+static struct fgraph_ops fprofiler_ops = {
+ .entryfunc = &profile_graph_entry,
+ .retfunc = &profile_graph_return,
+};
+
static int register_ftrace_profiler(void)
{
- return register_ftrace_graph(&profile_graph_return,
- &profile_graph_entry);
+ return register_ftrace_graph(&fprofiler_ops);
}
static void unregister_ftrace_profiler(void)
{
- unregister_ftrace_graph();
+ unregister_ftrace_graph(&fprofiler_ops);
}
#else
static struct ftrace_ops ftrace_profile_ops __read_mostly = {
@@ -936,7 +913,7 @@
ftrace_profile_enabled = 0;
/*
* unregister_ftrace_profiler calls stop_machine
- * so this acts like an synchronize_sched.
+ * so this acts like an synchronize_rcu.
*/
unregister_ftrace_profiler();
}
@@ -1023,12 +1000,6 @@
}
#endif /* CONFIG_FUNCTION_PROFILER */
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-static int ftrace_graph_active;
-#else
-# define ftrace_graph_active 0
-#endif
-
#ifdef CONFIG_DYNAMIC_FTRACE
static struct ftrace_ops *removed_ops;
@@ -1042,11 +1013,6 @@
#ifndef CONFIG_FTRACE_MCOUNT_RECORD
# error Dynamic ftrace depends on MCOUNT_RECORD
#endif
-
-struct ftrace_func_entry {
- struct hlist_node hlist;
- unsigned long ip;
-};
struct ftrace_func_probe {
struct ftrace_probe_ops *probe_ops;
@@ -1069,7 +1035,7 @@
};
#define EMPTY_HASH ((struct ftrace_hash *)&empty_hash)
-static struct ftrace_ops global_ops = {
+struct ftrace_ops global_ops = {
.func = ftrace_stub,
.local_hash.notrace_hash = EMPTY_HASH,
.local_hash.filter_hash = EMPTY_HASH,
@@ -1088,7 +1054,7 @@
/*
* Some of the ops may be dynamically allocated,
- * they are freed after a synchronize_sched().
+ * they are freed after a synchronize_rcu().
*/
preempt_disable_notrace();
@@ -1125,14 +1091,11 @@
struct ftrace_page *next;
struct dyn_ftrace *records;
int index;
- int size;
+ int order;
};
#define ENTRY_SIZE sizeof(struct dyn_ftrace)
#define ENTRIES_PER_PAGE (PAGE_SIZE / ENTRY_SIZE)
-
-/* estimate from running different kernels */
-#define NR_TO_INIT 10000
static struct ftrace_page *ftrace_pages_start;
static struct ftrace_page *ftrace_pages;
@@ -1288,7 +1251,7 @@
{
if (!hash || hash == EMPTY_HASH)
return;
- call_rcu_sched(&hash->rcu, __free_ftrace_hash_rcu);
+ call_rcu(&hash->rcu, __free_ftrace_hash_rcu);
}
void ftrace_free_filter(struct ftrace_ops *ops)
@@ -1332,6 +1295,7 @@
if (!ftrace_mod)
return -ENOMEM;
+ INIT_LIST_HEAD(&ftrace_mod->list);
ftrace_mod->func = kstrdup(func, GFP_KERNEL);
ftrace_mod->module = kstrdup(module, GFP_KERNEL);
ftrace_mod->enable = enable;
@@ -1395,28 +1359,20 @@
static int ftrace_hash_ipmodify_update(struct ftrace_ops *ops,
struct ftrace_hash *new_hash);
-static struct ftrace_hash *
-__ftrace_hash_move(struct ftrace_hash *src)
+static struct ftrace_hash *dup_hash(struct ftrace_hash *src, int size)
{
struct ftrace_func_entry *entry;
- struct hlist_node *tn;
- struct hlist_head *hhd;
struct ftrace_hash *new_hash;
- int size = src->count;
+ struct hlist_head *hhd;
+ struct hlist_node *tn;
int bits = 0;
int i;
/*
- * If the new source is empty, just return the empty_hash.
+ * Use around half the size (max bit of it), but
+ * a minimum of 2 is fine (as size of 0 or 1 both give 1 for bits).
*/
- if (ftrace_hash_empty(src))
- return EMPTY_HASH;
-
- /*
- * Make the hash size about 1/2 the # found
- */
- for (size /= 2; size; size >>= 1)
- bits++;
+ bits = fls(size / 2);
/* Don't allocate too much */
if (bits > FTRACE_HASH_MAX_BITS)
@@ -1436,8 +1392,21 @@
__add_hash_entry(new_hash, entry);
}
}
-
return new_hash;
+}
+
+static struct ftrace_hash *
+__ftrace_hash_move(struct ftrace_hash *src)
+{
+ int size = src->count;
+
+ /*
+ * If the new source is empty, just return the empty_hash.
+ */
+ if (ftrace_hash_empty(src))
+ return EMPTY_HASH;
+
+ return dup_hash(src, size);
}
static int
@@ -1483,7 +1452,7 @@
{
/*
* The function record is a match if it exists in the filter
- * hash and not in the notrace hash. Note, an emty hash is
+ * hash and not in the notrace hash. Note, an empty hash is
* considered a match for the filter hash, but an empty
* notrace hash is considered not in the notrace hash.
*/
@@ -1503,9 +1472,9 @@
* the ip is not in the ops->notrace_hash.
*
* This needs to be called with preemption disabled as
- * the hashes are freed with call_rcu_sched().
+ * the hashes are freed with call_rcu().
*/
-static int
+int
ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs)
{
struct ftrace_ops_hash hash;
@@ -1559,6 +1528,29 @@
return 0;
}
+static struct dyn_ftrace *lookup_rec(unsigned long start, unsigned long end)
+{
+ struct ftrace_page *pg;
+ struct dyn_ftrace *rec = NULL;
+ struct dyn_ftrace key;
+
+ key.ip = start;
+ key.flags = end; /* overload flags, as it is unsigned long */
+
+ for (pg = ftrace_pages_start; pg; pg = pg->next) {
+ if (pg->index == 0 ||
+ end < pg->records[0].ip ||
+ start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE))
+ continue;
+ rec = bsearch(&key, pg->records, pg->index,
+ sizeof(struct dyn_ftrace),
+ ftrace_cmp_recs);
+ if (rec)
+ break;
+ }
+ return rec;
+}
+
/**
* ftrace_location_range - return the first address of a traced location
* if it touches the given ip range
@@ -1573,23 +1565,11 @@
*/
unsigned long ftrace_location_range(unsigned long start, unsigned long end)
{
- struct ftrace_page *pg;
struct dyn_ftrace *rec;
- struct dyn_ftrace key;
- key.ip = start;
- key.flags = end; /* overload flags, as it is unsigned long */
-
- for (pg = ftrace_pages_start; pg; pg = pg->next) {
- if (end < pg->records[0].ip ||
- start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE))
- continue;
- rec = bsearch(&key, pg->records, pg->index,
- sizeof(struct dyn_ftrace),
- ftrace_cmp_recs);
- if (rec)
- return rec->ip;
- }
+ rec = lookup_rec(start, end);
+ if (rec)
+ return rec->ip;
return 0;
}
@@ -1742,6 +1722,9 @@
if (FTRACE_WARN_ON(ftrace_rec_count(rec) == FTRACE_REF_MAX))
return false;
+ if (ops->flags & FTRACE_OPS_FL_DIRECT)
+ rec->flags |= FTRACE_FL_DIRECT;
+
/*
* If there's only a single callback registered to a
* function, and the ops has a trampoline registered
@@ -1768,6 +1751,15 @@
if (FTRACE_WARN_ON(ftrace_rec_count(rec) == 0))
return false;
rec->flags--;
+
+ /*
+ * Only the internal direct_ops should have the
+ * DIRECT flag set. Thus, if it is removing a
+ * function, then that function should no longer
+ * be direct.
+ */
+ if (ops->flags & FTRACE_OPS_FL_DIRECT)
+ rec->flags &= ~FTRACE_FL_DIRECT;
/*
* If the rec had REGS enabled and the ops that is
@@ -1803,7 +1795,7 @@
count++;
/* Must match FTRACE_UPDATE_CALLS in ftrace_modify_all_code() */
- update |= ftrace_test_record(rec, 1) != FTRACE_UPDATE_IGNORE;
+ update |= ftrace_test_record(rec, true) != FTRACE_UPDATE_IGNORE;
/* Shortcut, if we handled all records, we are done. */
if (!all && count == hash->count)
@@ -1981,7 +1973,7 @@
char ins[MCOUNT_INSN_SIZE];
int i;
- if (probe_kernel_read(ins, p, MCOUNT_INSN_SIZE)) {
+ if (copy_from_kernel_nofault(ins, p, MCOUNT_INSN_SIZE)) {
printk(KERN_CONT "%s[FAULT] %px\n", fmt, p);
return;
}
@@ -2025,22 +2017,22 @@
* modifying the code. @failed should be one of either:
* EFAULT - if the problem happens on reading the @ip address
* EINVAL - if what is read at @ip is not what was expected
- * EPERM - if the problem happens on writting to the @ip address
+ * EPERM - if the problem happens on writing to the @ip address
*/
void ftrace_bug(int failed, struct dyn_ftrace *rec)
{
unsigned long ip = rec ? rec->ip : 0;
+ pr_info("------------[ ftrace bug ]------------\n");
+
switch (failed) {
case -EFAULT:
- FTRACE_WARN_ON_ONCE(1);
pr_info("ftrace faulted on modifying ");
- print_ip_sym(ip);
+ print_ip_sym(KERN_INFO, ip);
break;
case -EINVAL:
- FTRACE_WARN_ON_ONCE(1);
pr_info("ftrace failed to modify ");
- print_ip_sym(ip);
+ print_ip_sym(KERN_INFO, ip);
print_ip_ins(" actual: ", (unsigned char *)ip);
pr_cont("\n");
if (ftrace_expected) {
@@ -2049,14 +2041,12 @@
}
break;
case -EPERM:
- FTRACE_WARN_ON_ONCE(1);
pr_info("ftrace faulted on writing ");
- print_ip_sym(ip);
+ print_ip_sym(KERN_INFO, ip);
break;
default:
- FTRACE_WARN_ON_ONCE(1);
pr_info("ftrace faulted on unknown error ");
- print_ip_sym(ip);
+ print_ip_sym(KERN_INFO, ip);
}
print_bug_type();
if (rec) {
@@ -2081,9 +2071,11 @@
ip = ftrace_get_addr_curr(rec);
pr_cont("\n expected tramp: %lx\n", ip);
}
+
+ FTRACE_WARN_ON_ONCE(1);
}
-static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update)
+static int ftrace_check_record(struct dyn_ftrace *rec, bool enable, bool update)
{
unsigned long flag = 0UL;
@@ -2110,15 +2102,34 @@
* If enabling and the REGS flag does not match the REGS_EN, or
* the TRAMP flag doesn't match the TRAMP_EN, then do not ignore
* this record. Set flags to fail the compare against ENABLED.
+ * Same for direct calls.
*/
if (flag) {
- if (!(rec->flags & FTRACE_FL_REGS) !=
+ if (!(rec->flags & FTRACE_FL_REGS) !=
!(rec->flags & FTRACE_FL_REGS_EN))
flag |= FTRACE_FL_REGS;
- if (!(rec->flags & FTRACE_FL_TRAMP) !=
+ if (!(rec->flags & FTRACE_FL_TRAMP) !=
!(rec->flags & FTRACE_FL_TRAMP_EN))
flag |= FTRACE_FL_TRAMP;
+
+ /*
+ * Direct calls are special, as count matters.
+ * We must test the record for direct, if the
+ * DIRECT and DIRECT_EN do not match, but only
+ * if the count is 1. That's because, if the
+ * count is something other than one, we do not
+ * want the direct enabled (it will be done via the
+ * direct helper). But if DIRECT_EN is set, and
+ * the count is not one, we need to clear it.
+ */
+ if (ftrace_rec_count(rec) == 1) {
+ if (!(rec->flags & FTRACE_FL_DIRECT) !=
+ !(rec->flags & FTRACE_FL_DIRECT_EN))
+ flag |= FTRACE_FL_DIRECT;
+ } else if (rec->flags & FTRACE_FL_DIRECT_EN) {
+ flag |= FTRACE_FL_DIRECT;
+ }
}
/* If the state of this record hasn't changed, then do nothing */
@@ -2142,6 +2153,25 @@
rec->flags |= FTRACE_FL_TRAMP_EN;
else
rec->flags &= ~FTRACE_FL_TRAMP_EN;
+ }
+ if (flag & FTRACE_FL_DIRECT) {
+ /*
+ * If there's only one user (direct_ops helper)
+ * then we can call the direct function
+ * directly (no ftrace trampoline).
+ */
+ if (ftrace_rec_count(rec) == 1) {
+ if (rec->flags & FTRACE_FL_DIRECT)
+ rec->flags |= FTRACE_FL_DIRECT_EN;
+ else
+ rec->flags &= ~FTRACE_FL_DIRECT_EN;
+ } else {
+ /*
+ * Can only call directly if there's
+ * only one callback to the function.
+ */
+ rec->flags &= ~FTRACE_FL_DIRECT_EN;
+ }
}
}
@@ -2172,7 +2202,7 @@
* and REGS states. The _EN flags must be disabled though.
*/
rec->flags &= ~(FTRACE_FL_ENABLED | FTRACE_FL_TRAMP_EN |
- FTRACE_FL_REGS_EN);
+ FTRACE_FL_REGS_EN | FTRACE_FL_DIRECT_EN);
}
ftrace_bug_type = FTRACE_BUG_NOP;
@@ -2182,28 +2212,28 @@
/**
* ftrace_update_record, set a record that now is tracing or not
* @rec: the record to update
- * @enable: set to 1 if the record is tracing, zero to force disable
+ * @enable: set to true if the record is tracing, false to force disable
*
* The records that represent all functions that can be traced need
* to be updated when tracing has been enabled.
*/
-int ftrace_update_record(struct dyn_ftrace *rec, int enable)
+int ftrace_update_record(struct dyn_ftrace *rec, bool enable)
{
- return ftrace_check_record(rec, enable, 1);
+ return ftrace_check_record(rec, enable, true);
}
/**
* ftrace_test_record, check if the record has been enabled or not
* @rec: the record to test
- * @enable: set to 1 to check if enabled, 0 if it is disabled
+ * @enable: set to true to check if enabled, false if it is disabled
*
* The arch code may need to test if a record is already set to
* tracing to determine how to modify the function code that it
* represents.
*/
-int ftrace_test_record(struct dyn_ftrace *rec, int enable)
+int ftrace_test_record(struct dyn_ftrace *rec, bool enable)
{
- return ftrace_check_record(rec, enable, 0);
+ return ftrace_check_record(rec, enable, false);
}
static struct ftrace_ops *
@@ -2255,7 +2285,7 @@
if (hash_contains_ip(ip, op->func_hash))
return op;
- }
+ }
return NULL;
}
@@ -2345,19 +2375,77 @@
return NULL;
}
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
+/* Protected by rcu_tasks for reading, and direct_mutex for writing */
+static struct ftrace_hash *direct_functions = EMPTY_HASH;
+static DEFINE_MUTEX(direct_mutex);
+int ftrace_direct_func_count;
+
+/*
+ * Search the direct_functions hash to see if the given instruction pointer
+ * has a direct caller attached to it.
+ */
+unsigned long ftrace_find_rec_direct(unsigned long ip)
+{
+ struct ftrace_func_entry *entry;
+
+ entry = __ftrace_lookup_ip(direct_functions, ip);
+ if (!entry)
+ return 0;
+
+ return entry->direct;
+}
+
+static void call_direct_funcs(unsigned long ip, unsigned long pip,
+ struct ftrace_ops *ops, struct pt_regs *regs)
+{
+ unsigned long addr;
+
+ addr = ftrace_find_rec_direct(ip);
+ if (!addr)
+ return;
+
+ arch_ftrace_set_direct_caller(regs, addr);
+}
+
+struct ftrace_ops direct_ops = {
+ .func = call_direct_funcs,
+ .flags = FTRACE_OPS_FL_IPMODIFY | FTRACE_OPS_FL_RECURSION_SAFE
+ | FTRACE_OPS_FL_DIRECT | FTRACE_OPS_FL_SAVE_REGS
+ | FTRACE_OPS_FL_PERMANENT,
+ /*
+ * By declaring the main trampoline as this trampoline
+ * it will never have one allocated for it. Allocated
+ * trampolines should not call direct functions.
+ * The direct_ops should only be called by the builtin
+ * ftrace_regs_caller trampoline.
+ */
+ .trampoline = FTRACE_REGS_ADDR,
+};
+#endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */
+
/**
* ftrace_get_addr_new - Get the call address to set to
* @rec: The ftrace record descriptor
*
* If the record has the FTRACE_FL_REGS set, that means that it
* wants to convert to a callback that saves all regs. If FTRACE_FL_REGS
- * is not not set, then it wants to convert to the normal callback.
+ * is not set, then it wants to convert to the normal callback.
*
* Returns the address of the trampoline to set to
*/
unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec)
{
struct ftrace_ops *ops;
+ unsigned long addr;
+
+ if ((rec->flags & FTRACE_FL_DIRECT) &&
+ (ftrace_rec_count(rec) == 1)) {
+ addr = ftrace_find_rec_direct(rec->ip);
+ if (addr)
+ return addr;
+ WARN_ON_ONCE(1);
+ }
/* Trampolines take precedence over regs */
if (rec->flags & FTRACE_FL_TRAMP) {
@@ -2390,6 +2478,15 @@
unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec)
{
struct ftrace_ops *ops;
+ unsigned long addr;
+
+ /* Direct calls take precedence over trampolines */
+ if (rec->flags & FTRACE_FL_DIRECT_EN) {
+ addr = ftrace_find_rec_direct(rec->ip);
+ if (addr)
+ return addr;
+ WARN_ON_ONCE(1);
+ }
/* Trampolines take precedence over regs */
if (rec->flags & FTRACE_FL_TRAMP_EN) {
@@ -2410,7 +2507,7 @@
}
static int
-__ftrace_replace_code(struct dyn_ftrace *rec, int enable)
+__ftrace_replace_code(struct dyn_ftrace *rec, bool enable)
{
unsigned long ftrace_old_addr;
unsigned long ftrace_addr;
@@ -2442,13 +2539,15 @@
return ftrace_modify_call(rec, ftrace_old_addr, ftrace_addr);
}
- return -1; /* unknow ftrace bug */
+ return -1; /* unknown ftrace bug */
}
-void __weak ftrace_replace_code(int enable)
+void __weak ftrace_replace_code(int mod_flags)
{
struct dyn_ftrace *rec;
struct ftrace_page *pg;
+ bool enable = mod_flags & FTRACE_MODIFY_ENABLE_FL;
+ int schedulable = mod_flags & FTRACE_MODIFY_MAY_SLEEP_FL;
int failed;
if (unlikely(ftrace_disabled))
@@ -2465,6 +2564,8 @@
/* Stop processing */
return;
}
+ if (schedulable)
+ cond_resched();
} while_for_each_ftrace_rec();
}
@@ -2541,14 +2642,14 @@
}
static int
-ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec)
+ftrace_nop_initialize(struct module *mod, struct dyn_ftrace *rec)
{
int ret;
if (unlikely(ftrace_disabled))
return 0;
- ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR);
+ ret = ftrace_init_nop(mod, rec);
if (ret) {
ftrace_bug_type = FTRACE_BUG_INIT;
ftrace_bug(ret, rec);
@@ -2578,7 +2679,11 @@
void ftrace_modify_all_code(int command)
{
int update = command & FTRACE_UPDATE_TRACE_FUNC;
+ int mod_flags = 0;
int err = 0;
+
+ if (command & FTRACE_MAY_SLEEP)
+ mod_flags = FTRACE_MODIFY_MAY_SLEEP_FL;
/*
* If the ftrace_caller calls a ftrace_ops func directly,
@@ -2597,9 +2702,9 @@
}
if (command & FTRACE_UPDATE_CALLS)
- ftrace_replace_code(1);
+ ftrace_replace_code(mod_flags | FTRACE_MODIFY_ENABLE_FL);
else if (command & FTRACE_DISABLE_CALLS)
- ftrace_replace_code(0);
+ ftrace_replace_code(mod_flags);
if (update && ftrace_trace_function != ftrace_ops_list_func) {
function_trace_op = set_function_trace_op;
@@ -2692,6 +2797,51 @@
{
}
+/* List of trace_ops that have allocated trampolines */
+static LIST_HEAD(ftrace_ops_trampoline_list);
+
+static void ftrace_add_trampoline_to_kallsyms(struct ftrace_ops *ops)
+{
+ lockdep_assert_held(&ftrace_lock);
+ list_add_rcu(&ops->list, &ftrace_ops_trampoline_list);
+}
+
+static void ftrace_remove_trampoline_from_kallsyms(struct ftrace_ops *ops)
+{
+ lockdep_assert_held(&ftrace_lock);
+ list_del_rcu(&ops->list);
+ synchronize_rcu();
+}
+
+/*
+ * "__builtin__ftrace" is used as a module name in /proc/kallsyms for symbols
+ * for pages allocated for ftrace purposes, even though "__builtin__ftrace" is
+ * not a module.
+ */
+#define FTRACE_TRAMPOLINE_MOD "__builtin__ftrace"
+#define FTRACE_TRAMPOLINE_SYM "ftrace_trampoline"
+
+static void ftrace_trampoline_free(struct ftrace_ops *ops)
+{
+ if (ops && (ops->flags & FTRACE_OPS_FL_ALLOC_TRAMP) &&
+ ops->trampoline) {
+ /*
+ * Record the text poke event before the ksymbol unregister
+ * event.
+ */
+ perf_event_text_poke((void *)ops->trampoline,
+ (void *)ops->trampoline,
+ ops->trampoline_size, NULL, 0);
+ perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_OOL,
+ ops->trampoline, ops->trampoline_size,
+ true, FTRACE_TRAMPOLINE_SYM);
+ /* Remove from kallsyms after the perf events */
+ ftrace_remove_trampoline_from_kallsyms(ops);
+ }
+
+ arch_ftrace_trampoline_free(ops);
+}
+
static void ftrace_startup_enable(int command)
{
if (saved_ftrace_func != ftrace_trace_function) {
@@ -2712,7 +2862,7 @@
update_all_ops = false;
}
-static int ftrace_startup(struct ftrace_ops *ops, int command)
+int ftrace_startup(struct ftrace_ops *ops, int command)
{
int ret;
@@ -2741,6 +2891,8 @@
__unregister_ftrace_function(ops);
ftrace_start_up--;
ops->flags &= ~FTRACE_OPS_FL_ENABLED;
+ if (ops->flags & FTRACE_OPS_FL_DYNAMIC)
+ ftrace_trampoline_free(ops);
return ret;
}
@@ -2749,12 +2901,22 @@
ftrace_startup_enable(command);
+ /*
+ * If ftrace is in an undefined state, we just remove ops from list
+ * to prevent the NULL pointer, instead of totally rolling it back and
+ * free trampoline, because those actions could cause further damage.
+ */
+ if (unlikely(ftrace_disabled)) {
+ __unregister_ftrace_function(ops);
+ return -ENODEV;
+ }
+
ops->flags &= ~FTRACE_OPS_FL_ADDING;
return 0;
}
-static int ftrace_shutdown(struct ftrace_ops *ops, int command)
+int ftrace_shutdown(struct ftrace_ops *ops, int command)
{
int ret;
@@ -2786,18 +2948,8 @@
command |= FTRACE_UPDATE_TRACE_FUNC;
}
- if (!command || !ftrace_enabled) {
- /*
- * If these are dynamic or per_cpu ops, they still
- * need their data freed. Since, function tracing is
- * not currently active, we can just free them
- * without synchronizing all CPUs.
- */
- if (ops->flags & FTRACE_OPS_FL_DYNAMIC)
- goto free_ops;
-
- return 0;
- }
+ if (!command || !ftrace_enabled)
+ goto out;
/*
* If the ops uses a trampoline, then it needs to be
@@ -2834,6 +2986,7 @@
removed_ops = NULL;
ops->flags &= ~FTRACE_OPS_FL_REMOVING;
+out:
/*
* Dynamic ops may be freed, we must make sure that all
* callers are done before leaving this function.
@@ -2849,20 +3002,19 @@
* infrastructure to do the synchronization, thus we must do it
* ourselves.
*/
- schedule_on_each_cpu(ftrace_sync);
+ synchronize_rcu_tasks_rude();
/*
- * When the kernel is preeptive, tasks can be preempted
+ * When the kernel is preemptive, tasks can be preempted
* while on a ftrace trampoline. Just scheduling a task on
* a CPU is not good enough to flush them. Calling
* synchornize_rcu_tasks() will wait for those tasks to
* execute and either schedule voluntarily or enter user space.
*/
- if (IS_ENABLED(CONFIG_PREEMPT))
+ if (IS_ENABLED(CONFIG_PREEMPTION))
synchronize_rcu_tasks();
- free_ops:
- arch_ftrace_trampoline_free(ops);
+ ftrace_trampoline_free(ops);
}
return 0;
@@ -2904,6 +3056,8 @@
static u64 ftrace_update_time;
unsigned long ftrace_update_tot_cnt;
+unsigned long ftrace_number_of_pages;
+unsigned long ftrace_number_of_groups;
static inline int ops_traces_mod(struct ftrace_ops *ops)
{
@@ -2986,7 +3140,7 @@
* to the NOP instructions.
*/
if (!__is_defined(CC_USING_NOP_MCOUNT) &&
- !ftrace_code_disable(mod, p))
+ !ftrace_nop_initialize(mod, p))
break;
update_cnt++;
@@ -3003,18 +3157,20 @@
static int ftrace_allocate_records(struct ftrace_page *pg, int count)
{
int order;
+ int pages;
int cnt;
if (WARN_ON(!count))
return -EINVAL;
- order = get_count_order(DIV_ROUND_UP(count, ENTRIES_PER_PAGE));
+ pages = DIV_ROUND_UP(count, ENTRIES_PER_PAGE);
+ order = get_count_order(pages);
/*
* We want to fill as much as possible. No more than a page
* may be empty.
*/
- while ((PAGE_SIZE << order) / ENTRY_SIZE >= count + ENTRIES_PER_PAGE)
+ if (!is_power_of_2(pages))
order--;
again:
@@ -3024,12 +3180,15 @@
/* if we can't allocate this size, try something smaller */
if (!order)
return -ENOMEM;
- order >>= 1;
+ order--;
goto again;
}
+ ftrace_number_of_pages += 1 << order;
+ ftrace_number_of_groups++;
+
cnt = (PAGE_SIZE << order) / ENTRY_SIZE;
- pg->size = cnt;
+ pg->order = order;
if (cnt > count)
cnt = count;
@@ -3037,16 +3196,31 @@
return cnt;
}
+static void ftrace_free_pages(struct ftrace_page *pages)
+{
+ struct ftrace_page *pg = pages;
+
+ while (pg) {
+ if (pg->records) {
+ free_pages((unsigned long)pg->records, pg->order);
+ ftrace_number_of_pages -= 1 << pg->order;
+ }
+ pages = pg->next;
+ kfree(pg);
+ pg = pages;
+ ftrace_number_of_groups--;
+ }
+}
+
static struct ftrace_page *
ftrace_allocate_pages(unsigned long num_to_init)
{
struct ftrace_page *start_pg;
struct ftrace_page *pg;
- int order;
int cnt;
if (!num_to_init)
- return 0;
+ return NULL;
start_pg = pg = kzalloc(sizeof(*pg), GFP_KERNEL);
if (!pg)
@@ -3076,14 +3250,7 @@
return start_pg;
free_pages:
- pg = start_pg;
- while (pg) {
- order = get_count_order(pg->size / ENTRIES_PER_PAGE);
- free_pages((unsigned long)pg->records, order);
- start_pg = pg->next;
- kfree(pg);
- pg = start_pg;
- }
+ ftrace_free_pages(start_pg);
pr_info("ftrace: FAILED to allocate memory for functions\n");
return NULL;
}
@@ -3493,10 +3660,11 @@
if (iter->flags & FTRACE_ITER_ENABLED) {
struct ftrace_ops *ops;
- seq_printf(m, " (%ld)%s%s",
+ seq_printf(m, " (%ld)%s%s%s",
ftrace_rec_count(rec),
rec->flags & FTRACE_FL_REGS ? " R" : " ",
- rec->flags & FTRACE_FL_IPMODIFY ? " I" : " ");
+ rec->flags & FTRACE_FL_IPMODIFY ? " I" : " ",
+ rec->flags & FTRACE_FL_DIRECT ? " D" : " ");
if (rec->flags & FTRACE_FL_TRAMP_EN) {
ops = ftrace_find_tramp_ops_any(rec);
if (ops) {
@@ -3512,7 +3680,14 @@
} else {
add_trampoline_func(m, NULL, rec);
}
- }
+ if (rec->flags & FTRACE_FL_DIRECT) {
+ unsigned long direct;
+
+ direct = ftrace_find_rec_direct(rec->ip);
+ if (direct)
+ seq_printf(m, "\n\tdirect-->%pS", (void *)direct);
+ }
+ }
seq_putc(m, '\n');
@@ -3530,6 +3705,11 @@
ftrace_avail_open(struct inode *inode, struct file *file)
{
struct ftrace_iterator *iter;
+ int ret;
+
+ ret = security_locked_down(LOCKDOWN_TRACEFS);
+ if (ret)
+ return ret;
if (unlikely(ftrace_disabled))
return -ENODEV;
@@ -3548,6 +3728,15 @@
ftrace_enabled_open(struct inode *inode, struct file *file)
{
struct ftrace_iterator *iter;
+
+ /*
+ * This shows us what functions are currently being
+ * traced and by what. Not sure if we want lockdown
+ * to hide such critical information for an admin.
+ * Although, perhaps it can show information we don't
+ * want people to see, but if something is tracing
+ * something, we probably want to know about it.
+ */
iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter));
if (!iter)
@@ -3591,7 +3780,7 @@
if (unlikely(ftrace_disabled))
return -ENODEV;
- if (tr && trace_array_get(tr) < 0)
+ if (tracing_check_open_get_tr(tr))
return -ENODEV;
iter = kzalloc(sizeof(*iter), GFP_KERNEL);
@@ -3669,6 +3858,7 @@
{
struct ftrace_ops *ops = inode->i_private;
+ /* Checks for tracefs lockdown */
return ftrace_regex_open(ops,
FTRACE_ITER_FILTER | FTRACE_ITER_DO_PROBES,
inode, file);
@@ -3679,6 +3869,7 @@
{
struct ftrace_ops *ops = inode->i_private;
+ /* Checks for tracefs lockdown */
return ftrace_regex_open(ops, FTRACE_ITER_NOTRACE,
inode, file);
}
@@ -3759,6 +3950,31 @@
}
static int
+add_rec_by_index(struct ftrace_hash *hash, struct ftrace_glob *func_g,
+ int clear_filter)
+{
+ long index = simple_strtoul(func_g->search, NULL, 0);
+ struct ftrace_page *pg;
+ struct dyn_ftrace *rec;
+
+ /* The index starts at 1 */
+ if (--index < 0)
+ return 0;
+
+ do_for_each_ftrace_rec(pg, rec) {
+ if (pg->index <= index) {
+ index -= pg->index;
+ /* this is a double loop, break goes to the next page */
+ break;
+ }
+ rec = &pg->records[index];
+ enter_record(hash, rec, clear_filter);
+ return 1;
+ } while_for_each_ftrace_rec();
+ return 0;
+}
+
+static int
ftrace_match_record(struct dyn_ftrace *rec, struct ftrace_glob *func_g,
struct ftrace_glob *mod_g, int exclude_mod)
{
@@ -3825,6 +4041,11 @@
if (unlikely(ftrace_disabled))
goto out_unlock;
+
+ if (func_g.type == MATCH_INDEX) {
+ found = add_rec_by_index(hash, &func_g, clear_filter);
+ goto out_unlock;
+ }
do_for_each_ftrace_rec(pg, rec) {
@@ -3906,7 +4127,7 @@
static bool module_exists(const char *module)
{
/* All modules have the symbol __this_module */
- const char this_mod[] = "__this_module";
+ static const char this_mod[] = "__this_module";
char modname[MAX_PARAM_PREFIX_LEN + sizeof(this_mod) + 2];
unsigned long val;
int n;
@@ -4183,7 +4404,7 @@
* @ip: The instruction pointer address to map @data to
* @data: The data to map to @ip
*
- * Returns 0 on succes otherwise an error.
+ * Returns 0 on success otherwise an error.
*/
int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
unsigned long ip, void *data)
@@ -4213,7 +4434,7 @@
* @ip: The instruction pointer address to remove the data from
*
* Returns the data if it is found, otherwise NULL.
- * Note, if the data pointer is used as the data itself, (see
+ * Note, if the data pointer is used as the data itself, (see
* ftrace_func_mapper_find_ip(), then the return value may be meaningless,
* if the data pointer was set to zero.
*/
@@ -4351,7 +4572,7 @@
/*
* Note, there's a small window here that the func_hash->filter_hash
- * may be NULL or empty. Need to be carefule when reading the loop.
+ * may be NULL or empty. Need to be careful when reading the loop.
*/
mutex_lock(&probe->ops.func_hash->regex_lock);
@@ -4552,7 +4773,7 @@
if (ftrace_enabled && !ftrace_hash_empty(hash))
ftrace_run_modify_code(&probe->ops, FTRACE_UPDATE_CALLS,
&old_hash_ops);
- synchronize_sched();
+ synchronize_rcu();
hlist_for_each_entry_safe(entry, tmp, &hhd, hlist) {
hlist_del(&entry->hlist);
@@ -4794,8 +5015,404 @@
ftrace_set_addr(struct ftrace_ops *ops, unsigned long ip, int remove,
int reset, int enable)
{
- return ftrace_set_hash(ops, 0, 0, ip, remove, reset, enable);
+ return ftrace_set_hash(ops, NULL, 0, ip, remove, reset, enable);
}
+
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
+
+struct ftrace_direct_func {
+ struct list_head next;
+ unsigned long addr;
+ int count;
+};
+
+static LIST_HEAD(ftrace_direct_funcs);
+
+/**
+ * ftrace_find_direct_func - test an address if it is a registered direct caller
+ * @addr: The address of a registered direct caller
+ *
+ * This searches to see if a ftrace direct caller has been registered
+ * at a specific address, and if so, it returns a descriptor for it.
+ *
+ * This can be used by architecture code to see if an address is
+ * a direct caller (trampoline) attached to a fentry/mcount location.
+ * This is useful for the function_graph tracer, as it may need to
+ * do adjustments if it traced a location that also has a direct
+ * trampoline attached to it.
+ */
+struct ftrace_direct_func *ftrace_find_direct_func(unsigned long addr)
+{
+ struct ftrace_direct_func *entry;
+ bool found = false;
+
+ /* May be called by fgraph trampoline (protected by rcu tasks) */
+ list_for_each_entry_rcu(entry, &ftrace_direct_funcs, next) {
+ if (entry->addr == addr) {
+ found = true;
+ break;
+ }
+ }
+ if (found)
+ return entry;
+
+ return NULL;
+}
+
+static struct ftrace_direct_func *ftrace_alloc_direct_func(unsigned long addr)
+{
+ struct ftrace_direct_func *direct;
+
+ direct = kmalloc(sizeof(*direct), GFP_KERNEL);
+ if (!direct)
+ return NULL;
+ direct->addr = addr;
+ direct->count = 0;
+ list_add_rcu(&direct->next, &ftrace_direct_funcs);
+ ftrace_direct_func_count++;
+ return direct;
+}
+
+/**
+ * register_ftrace_direct - Call a custom trampoline directly
+ * @ip: The address of the nop at the beginning of a function
+ * @addr: The address of the trampoline to call at @ip
+ *
+ * This is used to connect a direct call from the nop location (@ip)
+ * at the start of ftrace traced functions. The location that it calls
+ * (@addr) must be able to handle a direct call, and save the parameters
+ * of the function being traced, and restore them (or inject new ones
+ * if needed), before returning.
+ *
+ * Returns:
+ * 0 on success
+ * -EBUSY - Another direct function is already attached (there can be only one)
+ * -ENODEV - @ip does not point to a ftrace nop location (or not supported)
+ * -ENOMEM - There was an allocation failure.
+ */
+int register_ftrace_direct(unsigned long ip, unsigned long addr)
+{
+ struct ftrace_direct_func *direct;
+ struct ftrace_func_entry *entry;
+ struct ftrace_hash *free_hash = NULL;
+ struct dyn_ftrace *rec;
+ int ret = -EBUSY;
+
+ mutex_lock(&direct_mutex);
+
+ /* See if there's a direct function at @ip already */
+ if (ftrace_find_rec_direct(ip))
+ goto out_unlock;
+
+ ret = -ENODEV;
+ rec = lookup_rec(ip, ip);
+ if (!rec)
+ goto out_unlock;
+
+ /*
+ * Check if the rec says it has a direct call but we didn't
+ * find one earlier?
+ */
+ if (WARN_ON(rec->flags & FTRACE_FL_DIRECT))
+ goto out_unlock;
+
+ /* Make sure the ip points to the exact record */
+ if (ip != rec->ip) {
+ ip = rec->ip;
+ /* Need to check this ip for a direct. */
+ if (ftrace_find_rec_direct(ip))
+ goto out_unlock;
+ }
+
+ ret = -ENOMEM;
+ if (ftrace_hash_empty(direct_functions) ||
+ direct_functions->count > 2 * (1 << direct_functions->size_bits)) {
+ struct ftrace_hash *new_hash;
+ int size = ftrace_hash_empty(direct_functions) ? 0 :
+ direct_functions->count + 1;
+
+ if (size < 32)
+ size = 32;
+
+ new_hash = dup_hash(direct_functions, size);
+ if (!new_hash)
+ goto out_unlock;
+
+ free_hash = direct_functions;
+ direct_functions = new_hash;
+ }
+
+ entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ goto out_unlock;
+
+ direct = ftrace_find_direct_func(addr);
+ if (!direct) {
+ direct = ftrace_alloc_direct_func(addr);
+ if (!direct) {
+ kfree(entry);
+ goto out_unlock;
+ }
+ }
+
+ entry->ip = ip;
+ entry->direct = addr;
+ __add_hash_entry(direct_functions, entry);
+
+ ret = ftrace_set_filter_ip(&direct_ops, ip, 0, 0);
+
+ if (!ret && !(direct_ops.flags & FTRACE_OPS_FL_ENABLED)) {
+ ret = register_ftrace_function(&direct_ops);
+ if (ret)
+ ftrace_set_filter_ip(&direct_ops, ip, 1, 0);
+ }
+
+ if (ret) {
+ remove_hash_entry(direct_functions, entry);
+ kfree(entry);
+ if (!direct->count) {
+ list_del_rcu(&direct->next);
+ synchronize_rcu_tasks();
+ kfree(direct);
+ if (free_hash)
+ free_ftrace_hash(free_hash);
+ free_hash = NULL;
+ ftrace_direct_func_count--;
+ }
+ } else {
+ direct->count++;
+ }
+ out_unlock:
+ mutex_unlock(&direct_mutex);
+
+ if (free_hash) {
+ synchronize_rcu_tasks();
+ free_ftrace_hash(free_hash);
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(register_ftrace_direct);
+
+static struct ftrace_func_entry *find_direct_entry(unsigned long *ip,
+ struct dyn_ftrace **recp)
+{
+ struct ftrace_func_entry *entry;
+ struct dyn_ftrace *rec;
+
+ rec = lookup_rec(*ip, *ip);
+ if (!rec)
+ return NULL;
+
+ entry = __ftrace_lookup_ip(direct_functions, rec->ip);
+ if (!entry) {
+ WARN_ON(rec->flags & FTRACE_FL_DIRECT);
+ return NULL;
+ }
+
+ WARN_ON(!(rec->flags & FTRACE_FL_DIRECT));
+
+ /* Passed in ip just needs to be on the call site */
+ *ip = rec->ip;
+
+ if (recp)
+ *recp = rec;
+
+ return entry;
+}
+
+int unregister_ftrace_direct(unsigned long ip, unsigned long addr)
+{
+ struct ftrace_direct_func *direct;
+ struct ftrace_func_entry *entry;
+ int ret = -ENODEV;
+
+ mutex_lock(&direct_mutex);
+
+ entry = find_direct_entry(&ip, NULL);
+ if (!entry)
+ goto out_unlock;
+
+ if (direct_functions->count == 1)
+ unregister_ftrace_function(&direct_ops);
+
+ ret = ftrace_set_filter_ip(&direct_ops, ip, 1, 0);
+
+ WARN_ON(ret);
+
+ remove_hash_entry(direct_functions, entry);
+
+ direct = ftrace_find_direct_func(addr);
+ if (!WARN_ON(!direct)) {
+ /* This is the good path (see the ! before WARN) */
+ direct->count--;
+ WARN_ON(direct->count < 0);
+ if (!direct->count) {
+ list_del_rcu(&direct->next);
+ synchronize_rcu_tasks();
+ kfree(direct);
+ kfree(entry);
+ ftrace_direct_func_count--;
+ }
+ }
+ out_unlock:
+ mutex_unlock(&direct_mutex);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(unregister_ftrace_direct);
+
+static struct ftrace_ops stub_ops = {
+ .func = ftrace_stub,
+};
+
+/**
+ * ftrace_modify_direct_caller - modify ftrace nop directly
+ * @entry: The ftrace hash entry of the direct helper for @rec
+ * @rec: The record representing the function site to patch
+ * @old_addr: The location that the site at @rec->ip currently calls
+ * @new_addr: The location that the site at @rec->ip should call
+ *
+ * An architecture may overwrite this function to optimize the
+ * changing of the direct callback on an ftrace nop location.
+ * This is called with the ftrace_lock mutex held, and no other
+ * ftrace callbacks are on the associated record (@rec). Thus,
+ * it is safe to modify the ftrace record, where it should be
+ * currently calling @old_addr directly, to call @new_addr.
+ *
+ * Safety checks should be made to make sure that the code at
+ * @rec->ip is currently calling @old_addr. And this must
+ * also update entry->direct to @new_addr.
+ */
+int __weak ftrace_modify_direct_caller(struct ftrace_func_entry *entry,
+ struct dyn_ftrace *rec,
+ unsigned long old_addr,
+ unsigned long new_addr)
+{
+ unsigned long ip = rec->ip;
+ int ret;
+
+ /*
+ * The ftrace_lock was used to determine if the record
+ * had more than one registered user to it. If it did,
+ * we needed to prevent that from changing to do the quick
+ * switch. But if it did not (only a direct caller was attached)
+ * then this function is called. But this function can deal
+ * with attached callers to the rec that we care about, and
+ * since this function uses standard ftrace calls that take
+ * the ftrace_lock mutex, we need to release it.
+ */
+ mutex_unlock(&ftrace_lock);
+
+ /*
+ * By setting a stub function at the same address, we force
+ * the code to call the iterator and the direct_ops helper.
+ * This means that @ip does not call the direct call, and
+ * we can simply modify it.
+ */
+ ret = ftrace_set_filter_ip(&stub_ops, ip, 0, 0);
+ if (ret)
+ goto out_lock;
+
+ ret = register_ftrace_function(&stub_ops);
+ if (ret) {
+ ftrace_set_filter_ip(&stub_ops, ip, 1, 0);
+ goto out_lock;
+ }
+
+ entry->direct = new_addr;
+
+ /*
+ * By removing the stub, we put back the direct call, calling
+ * the @new_addr.
+ */
+ unregister_ftrace_function(&stub_ops);
+ ftrace_set_filter_ip(&stub_ops, ip, 1, 0);
+
+ out_lock:
+ mutex_lock(&ftrace_lock);
+
+ return ret;
+}
+
+/**
+ * modify_ftrace_direct - Modify an existing direct call to call something else
+ * @ip: The instruction pointer to modify
+ * @old_addr: The address that the current @ip calls directly
+ * @new_addr: The address that the @ip should call
+ *
+ * This modifies a ftrace direct caller at an instruction pointer without
+ * having to disable it first. The direct call will switch over to the
+ * @new_addr without missing anything.
+ *
+ * Returns: zero on success. Non zero on error, which includes:
+ * -ENODEV : the @ip given has no direct caller attached
+ * -EINVAL : the @old_addr does not match the current direct caller
+ */
+int modify_ftrace_direct(unsigned long ip,
+ unsigned long old_addr, unsigned long new_addr)
+{
+ struct ftrace_direct_func *direct, *new_direct = NULL;
+ struct ftrace_func_entry *entry;
+ struct dyn_ftrace *rec;
+ int ret = -ENODEV;
+
+ mutex_lock(&direct_mutex);
+
+ mutex_lock(&ftrace_lock);
+ entry = find_direct_entry(&ip, &rec);
+ if (!entry)
+ goto out_unlock;
+
+ ret = -EINVAL;
+ if (entry->direct != old_addr)
+ goto out_unlock;
+
+ direct = ftrace_find_direct_func(old_addr);
+ if (WARN_ON(!direct))
+ goto out_unlock;
+ if (direct->count > 1) {
+ ret = -ENOMEM;
+ new_direct = ftrace_alloc_direct_func(new_addr);
+ if (!new_direct)
+ goto out_unlock;
+ direct->count--;
+ new_direct->count++;
+ } else {
+ direct->addr = new_addr;
+ }
+
+ /*
+ * If there's no other ftrace callback on the rec->ip location,
+ * then it can be changed directly by the architecture.
+ * If there is another caller, then we just need to change the
+ * direct caller helper to point to @new_addr.
+ */
+ if (ftrace_rec_count(rec) == 1) {
+ ret = ftrace_modify_direct_caller(entry, rec, old_addr, new_addr);
+ } else {
+ entry->direct = new_addr;
+ ret = 0;
+ }
+
+ if (ret) {
+ direct->addr = old_addr;
+ if (unlikely(new_direct)) {
+ direct->count++;
+ list_del_rcu(&new_direct->next);
+ synchronize_rcu_tasks();
+ kfree(new_direct);
+ ftrace_direct_func_count--;
+ }
+ }
+
+ out_unlock:
+ mutex_unlock(&ftrace_lock);
+ mutex_unlock(&direct_mutex);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(modify_ftrace_direct);
+#endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */
/**
* ftrace_set_filter_ip - set a function to filter on in ftrace by address
@@ -4967,7 +5584,7 @@
struct ftrace_hash *hash;
hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS);
- if (WARN_ON(!hash))
+ if (MEM_FAIL(!hash, "Failed to allocate hash\n"))
return;
while (buf) {
@@ -5045,8 +5662,12 @@
if (filter_hash) {
orig_hash = &iter->ops->func_hash->filter_hash;
- if (iter->tr && !list_empty(&iter->tr->mod_trace))
- iter->hash->flags |= FTRACE_HASH_FL_MOD;
+ if (iter->tr) {
+ if (list_empty(&iter->tr->mod_trace))
+ iter->hash->flags &= ~FTRACE_HASH_FL_MOD;
+ else
+ iter->hash->flags |= FTRACE_HASH_FL_MOD;
+ }
} else
orig_hash = &iter->ops->func_hash->notrace_hash;
@@ -5220,8 +5841,12 @@
__ftrace_graph_open(struct inode *inode, struct file *file,
struct ftrace_graph_data *fgd)
{
- int ret = 0;
+ int ret;
struct ftrace_hash *new_hash = NULL;
+
+ ret = security_locked_down(LOCKDOWN_TRACEFS);
+ if (ret)
+ return ret;
if (file->f_mode & FMODE_WRITE) {
const int size_bits = FTRACE_HASH_DEFAULT_BITS;
@@ -5382,7 +6007,7 @@
* infrastructure to do the synchronization, thus we must do it
* ourselves.
*/
- schedule_on_each_cpu(ftrace_sync);
+ synchronize_rcu_tasks_rude();
free_ftrace_hash(old_hash);
}
@@ -5514,7 +6139,7 @@
/*
* The name "destroy_filter_files" is really a misnomer. Although
- * in the future, it may actualy delete the files, but this is
+ * in the future, it may actually delete the files, but this is
* really intended to make sure the ops passed in are disabled
* and that when this function returns, the caller is free to
* free the ops.
@@ -5567,13 +6192,15 @@
return 0;
}
-static int __norecordmcount ftrace_process_locs(struct module *mod,
- unsigned long *start,
- unsigned long *end)
+static int ftrace_process_locs(struct module *mod,
+ unsigned long *start,
+ unsigned long *end)
{
+ struct ftrace_page *pg_unuse = NULL;
struct ftrace_page *start_pg;
struct ftrace_page *pg;
struct dyn_ftrace *rec;
+ unsigned long skipped = 0;
unsigned long count;
unsigned long *p;
unsigned long addr;
@@ -5619,6 +6246,7 @@
p = start;
pg = start_pg;
while (p < end) {
+ unsigned long end_offset;
addr = ftrace_call_adjust(*p++);
/*
* Some architecture linkers will pad between
@@ -5626,10 +6254,13 @@
* object files to satisfy alignments.
* Skip any NULL pointers.
*/
- if (!addr)
+ if (!addr) {
+ skipped++;
continue;
+ }
- if (pg->index == pg->size) {
+ end_offset = (pg->index+1) * sizeof(pg->records[0]);
+ if (end_offset > PAGE_SIZE << pg->order) {
/* We should have allocated enough */
if (WARN_ON(!pg->next))
break;
@@ -5640,8 +6271,10 @@
rec->ip = addr;
}
- /* We should have used all pages */
- WARN_ON(pg->next);
+ if (pg->next) {
+ pg_unuse = pg->next;
+ pg->next = NULL;
+ }
/* Assign the last page to ftrace_pages */
ftrace_pages = pg;
@@ -5663,6 +6296,11 @@
out:
mutex_unlock(&ftrace_lock);
+ /* We should have used all pages unless we skipped some */
+ if (pg_unuse) {
+ WARN_ON(!skipped);
+ ftrace_free_pages(pg_unuse);
+ }
return ret;
}
@@ -5683,6 +6321,27 @@
unsigned int num_funcs;
};
+static int ftrace_get_trampoline_kallsym(unsigned int symnum,
+ unsigned long *value, char *type,
+ char *name, char *module_name,
+ int *exported)
+{
+ struct ftrace_ops *op;
+
+ list_for_each_entry_rcu(op, &ftrace_ops_trampoline_list, list) {
+ if (!op->trampoline || symnum--)
+ continue;
+ *value = op->trampoline;
+ *type = 't';
+ strlcpy(name, FTRACE_TRAMPOLINE_SYM, KSYM_NAME_LEN);
+ strlcpy(module_name, FTRACE_TRAMPOLINE_MOD, MODULE_NAME_LEN);
+ *exported = 0;
+ return 0;
+ }
+
+ return -ERANGE;
+}
+
#ifdef CONFIG_MODULES
#define next_to_ftrace_page(p) container_of(p, struct ftrace_page, next)
@@ -5696,9 +6355,17 @@
for (ops = ftrace_ops_list; ops != &ftrace_list_end; ops = ops->next) {
if (ops_references_rec(ops, rec)) {
+ if (WARN_ON_ONCE(ops->flags & FTRACE_OPS_FL_DIRECT))
+ continue;
+ if (WARN_ON_ONCE(ops->flags & FTRACE_OPS_FL_IPMODIFY))
+ continue;
cnt++;
if (ops->flags & FTRACE_OPS_FL_SAVE_REGS)
rec->flags |= FTRACE_FL_REGS;
+ if (cnt == 1 && ops->trampoline)
+ rec->flags |= FTRACE_FL_TRAMP;
+ else
+ rec->flags &= ~FTRACE_FL_TRAMP;
}
}
@@ -5769,7 +6436,6 @@
struct ftrace_page **last_pg;
struct ftrace_page *tmp_page = NULL;
struct ftrace_page *pg;
- int order;
mutex_lock(&ftrace_lock);
@@ -5779,7 +6445,7 @@
list_for_each_entry_safe(mod_map, n, &ftrace_mod_maps, list) {
if (mod_map->mod == mod) {
list_del_rcu(&mod_map->list);
- call_rcu_sched(&mod_map->rcu, ftrace_free_mod_map);
+ call_rcu(&mod_map->rcu, ftrace_free_mod_map);
break;
}
}
@@ -5820,10 +6486,13 @@
/* Needs to be called outside of ftrace_lock */
clear_mod_from_hashes(pg);
- order = get_count_order(pg->size / ENTRIES_PER_PAGE);
- free_pages((unsigned long)pg->records, order);
+ if (pg->records) {
+ free_pages((unsigned long)pg->records, pg->order);
+ ftrace_number_of_pages -= 1 << pg->order;
+ }
tmp_page = pg->next;
kfree(pg);
+ ftrace_number_of_groups--;
}
}
@@ -5840,7 +6509,7 @@
/*
* If the tracing is enabled, go ahead and enable the record.
*
- * The reason not to enable the record immediatelly is the
+ * The reason not to enable the record immediately is the
* inherent check of ftrace_make_nop/ftrace_make_call for
* correct previous instructions. Making first the NOP
* conversion puts the module to the correct state, thus
@@ -5999,7 +6668,7 @@
struct ftrace_mod_map *mod_map;
const char *ret = NULL;
- /* mod_map is freed via call_rcu_sched() */
+ /* mod_map is freed via call_rcu() */
preempt_disable();
list_for_each_entry_rcu(mod_map, &ftrace_mod_maps, list) {
ret = ftrace_func_address_lookup(mod_map, addr, size, off, sym);
@@ -6020,6 +6689,7 @@
{
struct ftrace_mod_map *mod_map;
struct ftrace_mod_func *mod_func;
+ int ret;
preempt_disable();
list_for_each_entry_rcu(mod_map, &ftrace_mod_maps, list) {
@@ -6046,8 +6716,10 @@
WARN_ON(1);
break;
}
+ ret = ftrace_get_trampoline_kallsym(symnum, value, type, name,
+ module_name, exported);
preempt_enable();
- return -ERANGE;
+ return ret;
}
#else
@@ -6058,6 +6730,18 @@
unsigned long start, unsigned long end)
{
return NULL;
+}
+int ftrace_mod_get_kallsym(unsigned int symnum, unsigned long *value,
+ char *type, char *name, char *module_name,
+ int *exported)
+{
+ int ret;
+
+ preempt_disable();
+ ret = ftrace_get_trampoline_kallsym(symnum, value, type, name,
+ module_name, exported);
+ preempt_enable();
+ return ret;
}
#endif /* CONFIG_MODULES */
@@ -6072,11 +6756,7 @@
{
struct ftrace_func_entry *entry;
- if (ftrace_hash_empty(hash))
- return;
-
- entry = __ftrace_lookup_ip(hash, func->ip);
-
+ entry = ftrace_lookup_ip(hash, func->ip);
/*
* Do not allow this rec to match again.
* Yeah, it may waste some memory, but will be removed
@@ -6110,7 +6790,7 @@
func = kmalloc(sizeof(*func), GFP_KERNEL);
if (!func) {
- WARN_ONCE(1, "alloc failure, ftrace filter could be stale\n");
+ MEM_FAIL(1, "alloc failure, ftrace filter could be stale\n");
return;
}
@@ -6129,7 +6809,6 @@
struct ftrace_mod_map *mod_map = NULL;
struct ftrace_init_func *func, *func_next;
struct list_head clear_hash;
- int order;
INIT_LIST_HEAD(&clear_hash);
@@ -6167,8 +6846,11 @@
ftrace_update_tot_cnt--;
if (!pg->index) {
*last_pg = pg->next;
- order = get_count_order(pg->size / ENTRIES_PER_PAGE);
- free_pages((unsigned long)pg->records, order);
+ if (pg->records) {
+ free_pages((unsigned long)pg->records, pg->order);
+ ftrace_number_of_pages -= 1 << pg->order;
+ }
+ ftrace_number_of_groups--;
kfree(pg);
pg = container_of(last_pg, struct ftrace_page, next);
if (!(*last_pg))
@@ -6216,13 +6898,16 @@
}
pr_info("ftrace: allocating %ld entries in %ld pages\n",
- count, count / ENTRIES_PER_PAGE + 1);
+ count, DIV_ROUND_UP(count, ENTRIES_PER_PAGE));
last_ftrace_enabled = ftrace_enabled = 1;
ret = ftrace_process_locs(NULL,
__start_mcount_loc,
__stop_mcount_loc);
+
+ pr_info("ftrace: allocated %ld pages with %ld groups\n",
+ ftrace_number_of_pages, ftrace_number_of_groups);
set_ftrace_early_filters();
@@ -6238,7 +6923,24 @@
static void ftrace_update_trampoline(struct ftrace_ops *ops)
{
+ unsigned long trampoline = ops->trampoline;
+
arch_ftrace_update_trampoline(ops);
+ if (ops->trampoline && ops->trampoline != trampoline &&
+ (ops->flags & FTRACE_OPS_FL_ALLOC_TRAMP)) {
+ /* Add to kallsyms before the perf events */
+ ftrace_add_trampoline_to_kallsyms(ops);
+ perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_OOL,
+ ops->trampoline, ops->trampoline_size, false,
+ FTRACE_TRAMPOLINE_SYM);
+ /*
+ * Record the perf text poke event after the ksymbol register
+ * event.
+ */
+ perf_event_text_poke((void *)ops->trampoline, NULL, 0,
+ (void *)ops->trampoline,
+ ops->trampoline_size);
+ }
}
void ftrace_init_trace_array(struct trace_array *tr)
@@ -6249,7 +6951,7 @@
}
#else
-static struct ftrace_ops global_ops = {
+struct ftrace_ops global_ops = {
.func = ftrace_stub,
.flags = FTRACE_OPS_FL_RECURSION_SAFE |
FTRACE_OPS_FL_INITIALIZED |
@@ -6266,30 +6968,9 @@
static inline int ftrace_init_dyn_tracefs(struct dentry *d_tracer) { return 0; }
static inline void ftrace_startup_enable(int command) { }
static inline void ftrace_startup_all(int command) { }
-/* Keep as macros so we do not need to define the commands */
-# define ftrace_startup(ops, command) \
- ({ \
- int ___ret = __register_ftrace_function(ops); \
- if (!___ret) \
- (ops)->flags |= FTRACE_OPS_FL_ENABLED; \
- ___ret; \
- })
-# define ftrace_shutdown(ops, command) \
- ({ \
- int ___ret = __unregister_ftrace_function(ops); \
- if (!___ret) \
- (ops)->flags &= ~FTRACE_OPS_FL_ENABLED; \
- ___ret; \
- })
# define ftrace_startup_sysctl() do { } while (0)
# define ftrace_shutdown_sysctl() do { } while (0)
-
-static inline int
-ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs)
-{
- return 1;
-}
static void ftrace_update_trampoline(struct ftrace_ops *ops)
{
@@ -6334,11 +7015,14 @@
/*
* Some of the ops may be dynamically allocated,
- * they must be freed after a synchronize_sched().
+ * they must be freed after a synchronize_rcu().
*/
preempt_disable_notrace();
do_for_each_ftrace_op(op, ftrace_ops_list) {
+ /* Stub functions don't need to be called nor tested */
+ if (op->flags & FTRACE_OPS_FL_STUB)
+ continue;
/*
* Check the following for each ops before calling their func:
* if RCU flag is set, then rcu_is_watching() must be true
@@ -6383,8 +7067,7 @@
}
NOKPROBE_SYMBOL(ftrace_ops_list_func);
#else
-static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip,
- struct ftrace_ops *op, struct pt_regs *regs)
+static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip)
{
__ftrace_ops_list_func(ip, parent_ip, NULL, NULL);
}
@@ -6445,11 +7128,17 @@
{
struct trace_array *tr = data;
struct trace_pid_list *pid_list;
+ struct trace_pid_list *no_pid_list;
pid_list = rcu_dereference_sched(tr->function_pids);
+ no_pid_list = rcu_dereference_sched(tr->function_no_pids);
- this_cpu_write(tr->trace_buffer.data->ftrace_ignore_pid,
- trace_ignore_this_task(pid_list, next));
+ if (trace_ignore_this_task(pid_list, no_pid_list, next))
+ this_cpu_write(tr->array_buffer.data->ftrace_ignore_pid,
+ FTRACE_PID_IGNORE);
+ else
+ this_cpu_write(tr->array_buffer.data->ftrace_ignore_pid,
+ next->pid);
}
static void
@@ -6462,6 +7151,9 @@
pid_list = rcu_dereference_sched(tr->function_pids);
trace_filter_add_remove_task(pid_list, self, task);
+
+ pid_list = rcu_dereference_sched(tr->function_no_pids);
+ trace_filter_add_remove_task(pid_list, self, task);
}
static void
@@ -6471,6 +7163,9 @@
struct trace_array *tr = data;
pid_list = rcu_dereference_sched(tr->function_pids);
+ trace_filter_add_remove_task(pid_list, NULL, task);
+
+ pid_list = rcu_dereference_sched(tr->function_no_pids);
trace_filter_add_remove_task(pid_list, NULL, task);
}
@@ -6489,42 +7184,57 @@
}
}
-static void clear_ftrace_pids(struct trace_array *tr)
+static void clear_ftrace_pids(struct trace_array *tr, int type)
{
struct trace_pid_list *pid_list;
+ struct trace_pid_list *no_pid_list;
int cpu;
pid_list = rcu_dereference_protected(tr->function_pids,
lockdep_is_held(&ftrace_lock));
- if (!pid_list)
+ no_pid_list = rcu_dereference_protected(tr->function_no_pids,
+ lockdep_is_held(&ftrace_lock));
+
+ /* Make sure there's something to do */
+ if (!pid_type_enabled(type, pid_list, no_pid_list))
return;
- unregister_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr);
+ /* See if the pids still need to be checked after this */
+ if (!still_need_pid_events(type, pid_list, no_pid_list)) {
+ unregister_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr);
+ for_each_possible_cpu(cpu)
+ per_cpu_ptr(tr->array_buffer.data, cpu)->ftrace_ignore_pid = FTRACE_PID_TRACE;
+ }
- for_each_possible_cpu(cpu)
- per_cpu_ptr(tr->trace_buffer.data, cpu)->ftrace_ignore_pid = false;
+ if (type & TRACE_PIDS)
+ rcu_assign_pointer(tr->function_pids, NULL);
- rcu_assign_pointer(tr->function_pids, NULL);
+ if (type & TRACE_NO_PIDS)
+ rcu_assign_pointer(tr->function_no_pids, NULL);
/* Wait till all users are no longer using pid filtering */
- synchronize_sched();
+ synchronize_rcu();
- trace_free_pid_list(pid_list);
+ if ((type & TRACE_PIDS) && pid_list)
+ trace_free_pid_list(pid_list);
+
+ if ((type & TRACE_NO_PIDS) && no_pid_list)
+ trace_free_pid_list(no_pid_list);
}
void ftrace_clear_pids(struct trace_array *tr)
{
mutex_lock(&ftrace_lock);
- clear_ftrace_pids(tr);
+ clear_ftrace_pids(tr, TRACE_PIDS | TRACE_NO_PIDS);
mutex_unlock(&ftrace_lock);
}
-static void ftrace_pid_reset(struct trace_array *tr)
+static void ftrace_pid_reset(struct trace_array *tr, int type)
{
mutex_lock(&ftrace_lock);
- clear_ftrace_pids(tr);
+ clear_ftrace_pids(tr, type);
ftrace_update_pid_func();
ftrace_startup_all(0);
@@ -6588,21 +7298,71 @@
.show = fpid_show,
};
-static int
-ftrace_pid_open(struct inode *inode, struct file *file)
+static void *fnpid_start(struct seq_file *m, loff_t *pos)
+ __acquires(RCU)
{
+ struct trace_pid_list *pid_list;
+ struct trace_array *tr = m->private;
+
+ mutex_lock(&ftrace_lock);
+ rcu_read_lock_sched();
+
+ pid_list = rcu_dereference_sched(tr->function_no_pids);
+
+ if (!pid_list)
+ return !(*pos) ? FTRACE_NO_PIDS : NULL;
+
+ return trace_pid_start(pid_list, pos);
+}
+
+static void *fnpid_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ struct trace_array *tr = m->private;
+ struct trace_pid_list *pid_list = rcu_dereference_sched(tr->function_no_pids);
+
+ if (v == FTRACE_NO_PIDS) {
+ (*pos)++;
+ return NULL;
+ }
+ return trace_pid_next(pid_list, v, pos);
+}
+
+static const struct seq_operations ftrace_no_pid_sops = {
+ .start = fnpid_start,
+ .next = fnpid_next,
+ .stop = fpid_stop,
+ .show = fpid_show,
+};
+
+static int pid_open(struct inode *inode, struct file *file, int type)
+{
+ const struct seq_operations *seq_ops;
struct trace_array *tr = inode->i_private;
struct seq_file *m;
int ret = 0;
- if (trace_array_get(tr) < 0)
- return -ENODEV;
+ ret = tracing_check_open_get_tr(tr);
+ if (ret)
+ return ret;
if ((file->f_mode & FMODE_WRITE) &&
(file->f_flags & O_TRUNC))
- ftrace_pid_reset(tr);
+ ftrace_pid_reset(tr, type);
- ret = seq_open(file, &ftrace_pid_sops);
+ switch (type) {
+ case TRACE_PIDS:
+ seq_ops = &ftrace_pid_sops;
+ break;
+ case TRACE_NO_PIDS:
+ seq_ops = &ftrace_no_pid_sops;
+ break;
+ default:
+ trace_array_put(tr);
+ WARN_ON_ONCE(1);
+ return -EINVAL;
+ }
+
+ ret = seq_open(file, seq_ops);
if (ret < 0) {
trace_array_put(tr);
} else {
@@ -6614,10 +7374,23 @@
return ret;
}
+static int
+ftrace_pid_open(struct inode *inode, struct file *file)
+{
+ return pid_open(inode, file, TRACE_PIDS);
+}
+
+static int
+ftrace_no_pid_open(struct inode *inode, struct file *file)
+{
+ return pid_open(inode, file, TRACE_NO_PIDS);
+}
+
static void ignore_task_cpu(void *data)
{
struct trace_array *tr = data;
struct trace_pid_list *pid_list;
+ struct trace_pid_list *no_pid_list;
/*
* This function is called by on_each_cpu() while the
@@ -6625,18 +7398,25 @@
*/
pid_list = rcu_dereference_protected(tr->function_pids,
mutex_is_locked(&ftrace_lock));
+ no_pid_list = rcu_dereference_protected(tr->function_no_pids,
+ mutex_is_locked(&ftrace_lock));
- this_cpu_write(tr->trace_buffer.data->ftrace_ignore_pid,
- trace_ignore_this_task(pid_list, current));
+ if (trace_ignore_this_task(pid_list, no_pid_list, current))
+ this_cpu_write(tr->array_buffer.data->ftrace_ignore_pid,
+ FTRACE_PID_IGNORE);
+ else
+ this_cpu_write(tr->array_buffer.data->ftrace_ignore_pid,
+ current->pid);
}
static ssize_t
-ftrace_pid_write(struct file *filp, const char __user *ubuf,
- size_t cnt, loff_t *ppos)
+pid_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos, int type)
{
struct seq_file *m = filp->private_data;
struct trace_array *tr = m->private;
- struct trace_pid_list *filtered_pids = NULL;
+ struct trace_pid_list *filtered_pids;
+ struct trace_pid_list *other_pids;
struct trace_pid_list *pid_list;
ssize_t ret;
@@ -6645,19 +7425,43 @@
mutex_lock(&ftrace_lock);
- filtered_pids = rcu_dereference_protected(tr->function_pids,
+ switch (type) {
+ case TRACE_PIDS:
+ filtered_pids = rcu_dereference_protected(tr->function_pids,
lockdep_is_held(&ftrace_lock));
+ other_pids = rcu_dereference_protected(tr->function_no_pids,
+ lockdep_is_held(&ftrace_lock));
+ break;
+ case TRACE_NO_PIDS:
+ filtered_pids = rcu_dereference_protected(tr->function_no_pids,
+ lockdep_is_held(&ftrace_lock));
+ other_pids = rcu_dereference_protected(tr->function_pids,
+ lockdep_is_held(&ftrace_lock));
+ break;
+ default:
+ ret = -EINVAL;
+ WARN_ON_ONCE(1);
+ goto out;
+ }
ret = trace_pid_write(filtered_pids, &pid_list, ubuf, cnt);
if (ret < 0)
goto out;
- rcu_assign_pointer(tr->function_pids, pid_list);
+ switch (type) {
+ case TRACE_PIDS:
+ rcu_assign_pointer(tr->function_pids, pid_list);
+ break;
+ case TRACE_NO_PIDS:
+ rcu_assign_pointer(tr->function_no_pids, pid_list);
+ break;
+ }
+
if (filtered_pids) {
- synchronize_sched();
+ synchronize_rcu();
trace_free_pid_list(filtered_pids);
- } else if (pid_list) {
+ } else if (pid_list && !other_pids) {
/* Register a probe to set whether to ignore the tracing of a task */
register_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr);
}
@@ -6680,6 +7484,20 @@
return ret;
}
+static ssize_t
+ftrace_pid_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ return pid_write(filp, ubuf, cnt, ppos, TRACE_PIDS);
+}
+
+static ssize_t
+ftrace_no_pid_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ return pid_write(filp, ubuf, cnt, ppos, TRACE_NO_PIDS);
+}
+
static int
ftrace_pid_release(struct inode *inode, struct file *file)
{
@@ -6698,10 +7516,20 @@
.release = ftrace_pid_release,
};
+static const struct file_operations ftrace_no_pid_fops = {
+ .open = ftrace_no_pid_open,
+ .write = ftrace_no_pid_write,
+ .read = seq_read,
+ .llseek = tracing_lseek,
+ .release = ftrace_pid_release,
+};
+
void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer)
{
trace_create_file("set_ftrace_pid", 0644, d_tracer,
tr, &ftrace_pid_fops);
+ trace_create_file("set_ftrace_notrace_pid", 0644, d_tracer,
+ tr, &ftrace_no_pid_fops);
}
void __init ftrace_init_tracefs_toplevel(struct trace_array *tr,
@@ -6781,10 +7609,21 @@
}
EXPORT_SYMBOL_GPL(unregister_ftrace_function);
+static bool is_permanent_ops_registered(void)
+{
+ struct ftrace_ops *op;
+
+ do_for_each_ftrace_op(op, ftrace_ops_list) {
+ if (op->flags & FTRACE_OPS_FL_PERMANENT)
+ return true;
+ } while_for_each_ftrace_op(op);
+
+ return false;
+}
+
int
ftrace_enable_sysctl(struct ctl_table *table, int write,
- void __user *buffer, size_t *lenp,
- loff_t *ppos)
+ void *buffer, size_t *lenp, loff_t *ppos)
{
int ret = -ENODEV;
@@ -6798,8 +7637,6 @@
if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled))
goto out;
- last_ftrace_enabled = !!ftrace_enabled;
-
if (ftrace_enabled) {
/* we are starting ftrace again */
@@ -6810,364 +7647,20 @@
ftrace_startup_sysctl();
} else {
+ if (is_permanent_ops_registered()) {
+ ftrace_enabled = true;
+ ret = -EBUSY;
+ goto out;
+ }
+
/* stopping ftrace calls (just send to ftrace_stub) */
ftrace_trace_function = ftrace_stub;
ftrace_shutdown_sysctl();
}
+ last_ftrace_enabled = !!ftrace_enabled;
out:
mutex_unlock(&ftrace_lock);
return ret;
}
-
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-
-static struct ftrace_ops graph_ops = {
- .func = ftrace_stub,
- .flags = FTRACE_OPS_FL_RECURSION_SAFE |
- FTRACE_OPS_FL_INITIALIZED |
- FTRACE_OPS_FL_PID |
- FTRACE_OPS_FL_STUB,
-#ifdef FTRACE_GRAPH_TRAMP_ADDR
- .trampoline = FTRACE_GRAPH_TRAMP_ADDR,
- /* trampoline_size is only needed for dynamically allocated tramps */
-#endif
- ASSIGN_OPS_HASH(graph_ops, &global_ops.local_hash)
-};
-
-void ftrace_graph_sleep_time_control(bool enable)
-{
- fgraph_sleep_time = enable;
-}
-
-void ftrace_graph_graph_time_control(bool enable)
-{
- fgraph_graph_time = enable;
-}
-
-void ftrace_graph_return_stub(struct ftrace_graph_ret *trace)
-{
-}
-
-int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace)
-{
- return 0;
-}
-
-/* The callbacks that hook a function */
-trace_func_graph_ret_t ftrace_graph_return = ftrace_graph_return_stub;
-trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub;
-static trace_func_graph_ent_t __ftrace_graph_entry = ftrace_graph_entry_stub;
-
-/* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */
-static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list)
-{
- int i;
- int ret = 0;
- int start = 0, end = FTRACE_RETSTACK_ALLOC_SIZE;
- struct task_struct *g, *t;
-
- for (i = 0; i < FTRACE_RETSTACK_ALLOC_SIZE; i++) {
- ret_stack_list[i] =
- kmalloc_array(FTRACE_RETFUNC_DEPTH,
- sizeof(struct ftrace_ret_stack),
- GFP_KERNEL);
- if (!ret_stack_list[i]) {
- start = 0;
- end = i;
- ret = -ENOMEM;
- goto free;
- }
- }
-
- read_lock(&tasklist_lock);
- do_each_thread(g, t) {
- if (start == end) {
- ret = -EAGAIN;
- goto unlock;
- }
-
- if (t->ret_stack == NULL) {
- atomic_set(&t->trace_overrun, 0);
- t->curr_ret_stack = -1;
- t->curr_ret_depth = -1;
- /* Make sure the tasks see the -1 first: */
- smp_wmb();
- t->ret_stack = ret_stack_list[start++];
- }
- } while_each_thread(g, t);
-
-unlock:
- read_unlock(&tasklist_lock);
-free:
- for (i = start; i < end; i++)
- kfree(ret_stack_list[i]);
- return ret;
-}
-
-static void
-ftrace_graph_probe_sched_switch(void *ignore, bool preempt,
- struct task_struct *prev, struct task_struct *next)
-{
- unsigned long long timestamp;
- int index;
-
- /*
- * Does the user want to count the time a function was asleep.
- * If so, do not update the time stamps.
- */
- if (fgraph_sleep_time)
- return;
-
- timestamp = trace_clock_local();
-
- prev->ftrace_timestamp = timestamp;
-
- /* only process tasks that we timestamped */
- if (!next->ftrace_timestamp)
- return;
-
- /*
- * Update all the counters in next to make up for the
- * time next was sleeping.
- */
- timestamp -= next->ftrace_timestamp;
-
- for (index = next->curr_ret_stack; index >= 0; index--)
- next->ret_stack[index].calltime += timestamp;
-}
-
-/* Allocate a return stack for each task */
-static int start_graph_tracing(void)
-{
- struct ftrace_ret_stack **ret_stack_list;
- int ret, cpu;
-
- ret_stack_list = kmalloc_array(FTRACE_RETSTACK_ALLOC_SIZE,
- sizeof(struct ftrace_ret_stack *),
- GFP_KERNEL);
-
- if (!ret_stack_list)
- return -ENOMEM;
-
- /* The cpu_boot init_task->ret_stack will never be freed */
- for_each_online_cpu(cpu) {
- if (!idle_task(cpu)->ret_stack)
- ftrace_graph_init_idle_task(idle_task(cpu), cpu);
- }
-
- do {
- ret = alloc_retstack_tasklist(ret_stack_list);
- } while (ret == -EAGAIN);
-
- if (!ret) {
- ret = register_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL);
- if (ret)
- pr_info("ftrace_graph: Couldn't activate tracepoint"
- " probe to kernel_sched_switch\n");
- }
-
- kfree(ret_stack_list);
- return ret;
-}
-
-/*
- * Hibernation protection.
- * The state of the current task is too much unstable during
- * suspend/restore to disk. We want to protect against that.
- */
-static int
-ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state,
- void *unused)
-{
- switch (state) {
- case PM_HIBERNATION_PREPARE:
- pause_graph_tracing();
- break;
-
- case PM_POST_HIBERNATION:
- unpause_graph_tracing();
- break;
- }
- return NOTIFY_DONE;
-}
-
-static int ftrace_graph_entry_test(struct ftrace_graph_ent *trace)
-{
- if (!ftrace_ops_test(&global_ops, trace->func, NULL))
- return 0;
- return __ftrace_graph_entry(trace);
-}
-
-/*
- * The function graph tracer should only trace the functions defined
- * by set_ftrace_filter and set_ftrace_notrace. If another function
- * tracer ops is registered, the graph tracer requires testing the
- * function against the global ops, and not just trace any function
- * that any ftrace_ops registered.
- */
-static void update_function_graph_func(void)
-{
- struct ftrace_ops *op;
- bool do_test = false;
-
- /*
- * The graph and global ops share the same set of functions
- * to test. If any other ops is on the list, then
- * the graph tracing needs to test if its the function
- * it should call.
- */
- do_for_each_ftrace_op(op, ftrace_ops_list) {
- if (op != &global_ops && op != &graph_ops &&
- op != &ftrace_list_end) {
- do_test = true;
- /* in double loop, break out with goto */
- goto out;
- }
- } while_for_each_ftrace_op(op);
- out:
- if (do_test)
- ftrace_graph_entry = ftrace_graph_entry_test;
- else
- ftrace_graph_entry = __ftrace_graph_entry;
-}
-
-static struct notifier_block ftrace_suspend_notifier = {
- .notifier_call = ftrace_suspend_notifier_call,
-};
-
-int register_ftrace_graph(trace_func_graph_ret_t retfunc,
- trace_func_graph_ent_t entryfunc)
-{
- int ret = 0;
-
- mutex_lock(&ftrace_lock);
-
- /* we currently allow only one tracer registered at a time */
- if (ftrace_graph_active) {
- ret = -EBUSY;
- goto out;
- }
-
- register_pm_notifier(&ftrace_suspend_notifier);
-
- ftrace_graph_active++;
- ret = start_graph_tracing();
- if (ret) {
- ftrace_graph_active--;
- goto out;
- }
-
- ftrace_graph_return = retfunc;
-
- /*
- * Update the indirect function to the entryfunc, and the
- * function that gets called to the entry_test first. Then
- * call the update fgraph entry function to determine if
- * the entryfunc should be called directly or not.
- */
- __ftrace_graph_entry = entryfunc;
- ftrace_graph_entry = ftrace_graph_entry_test;
- update_function_graph_func();
-
- ret = ftrace_startup(&graph_ops, FTRACE_START_FUNC_RET);
-out:
- mutex_unlock(&ftrace_lock);
- return ret;
-}
-
-void unregister_ftrace_graph(void)
-{
- mutex_lock(&ftrace_lock);
-
- if (unlikely(!ftrace_graph_active))
- goto out;
-
- ftrace_graph_active--;
- ftrace_graph_return = ftrace_graph_return_stub;
- ftrace_graph_entry = ftrace_graph_entry_stub;
- __ftrace_graph_entry = ftrace_graph_entry_stub;
- ftrace_shutdown(&graph_ops, FTRACE_STOP_FUNC_RET);
- unregister_pm_notifier(&ftrace_suspend_notifier);
- unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL);
-
- out:
- mutex_unlock(&ftrace_lock);
-}
-
-static DEFINE_PER_CPU(struct ftrace_ret_stack *, idle_ret_stack);
-
-static void
-graph_init_task(struct task_struct *t, struct ftrace_ret_stack *ret_stack)
-{
- atomic_set(&t->trace_overrun, 0);
- t->ftrace_timestamp = 0;
- /* make curr_ret_stack visible before we add the ret_stack */
- smp_wmb();
- t->ret_stack = ret_stack;
-}
-
-/*
- * Allocate a return stack for the idle task. May be the first
- * time through, or it may be done by CPU hotplug online.
- */
-void ftrace_graph_init_idle_task(struct task_struct *t, int cpu)
-{
- t->curr_ret_stack = -1;
- t->curr_ret_depth = -1;
- /*
- * The idle task has no parent, it either has its own
- * stack or no stack at all.
- */
- if (t->ret_stack)
- WARN_ON(t->ret_stack != per_cpu(idle_ret_stack, cpu));
-
- if (ftrace_graph_active) {
- struct ftrace_ret_stack *ret_stack;
-
- ret_stack = per_cpu(idle_ret_stack, cpu);
- if (!ret_stack) {
- ret_stack =
- kmalloc_array(FTRACE_RETFUNC_DEPTH,
- sizeof(struct ftrace_ret_stack),
- GFP_KERNEL);
- if (!ret_stack)
- return;
- per_cpu(idle_ret_stack, cpu) = ret_stack;
- }
- graph_init_task(t, ret_stack);
- }
-}
-
-/* Allocate a return stack for newly created task */
-void ftrace_graph_init_task(struct task_struct *t)
-{
- /* Make sure we do not use the parent ret_stack */
- t->ret_stack = NULL;
- t->curr_ret_stack = -1;
- t->curr_ret_depth = -1;
-
- if (ftrace_graph_active) {
- struct ftrace_ret_stack *ret_stack;
-
- ret_stack = kmalloc_array(FTRACE_RETFUNC_DEPTH,
- sizeof(struct ftrace_ret_stack),
- GFP_KERNEL);
- if (!ret_stack)
- return;
- graph_init_task(t, ret_stack);
- }
-}
-
-void ftrace_graph_exit_task(struct task_struct *t)
-{
- struct ftrace_ret_stack *ret_stack = t->ret_stack;
-
- t->ret_stack = NULL;
- /* NULL must become visible to IRQs before we free it: */
- barrier();
-
- kfree(ret_stack);
-}
-#endif
--
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