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/padata.c | 878 +++++++++++++++++++++++++++++++++------------------------
1 files changed, 505 insertions(+), 373 deletions(-)
diff --git a/kernel/kernel/padata.c b/kernel/kernel/padata.c
index 93e4fb2..11ca3eb 100644
--- a/kernel/kernel/padata.c
+++ b/kernel/kernel/padata.c
@@ -2,10 +2,13 @@
/*
* padata.c - generic interface to process data streams in parallel
*
- * See Documentation/padata.txt for an api documentation.
+ * See Documentation/core-api/padata.rst for more information.
*
* Copyright (C) 2008, 2009 secunet Security Networks AG
* Copyright (C) 2008, 2009 Steffen Klassert <steffen.klassert@secunet.com>
+ *
+ * Copyright (c) 2020 Oracle and/or its affiliates.
+ * Author: Daniel Jordan <daniel.m.jordan@oracle.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
@@ -21,6 +24,7 @@
* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*/
+#include <linux/completion.h>
#include <linux/export.h>
#include <linux/cpumask.h>
#include <linux/err.h>
@@ -31,11 +35,30 @@
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/rcupdate.h>
-#include <linux/module.h>
-#define MAX_OBJ_NUM 1000
+#define PADATA_WORK_ONSTACK 1 /* Work's memory is on stack */
+
+struct padata_work {
+ struct work_struct pw_work;
+ struct list_head pw_list; /* padata_free_works linkage */
+ void *pw_data;
+};
+
+static DEFINE_SPINLOCK(padata_works_lock);
+static struct padata_work *padata_works;
+static LIST_HEAD(padata_free_works);
+
+struct padata_mt_job_state {
+ spinlock_t lock;
+ struct completion completion;
+ struct padata_mt_job *job;
+ int nworks;
+ int nworks_fini;
+ unsigned long chunk_size;
+};
static void padata_free_pd(struct parallel_data *pd);
+static void __init padata_mt_helper(struct work_struct *work);
static int padata_index_to_cpu(struct parallel_data *pd, int cpu_index)
{
@@ -48,101 +71,168 @@
return target_cpu;
}
-static int padata_cpu_hash(struct parallel_data *pd)
+static int padata_cpu_hash(struct parallel_data *pd, unsigned int seq_nr)
{
- unsigned int seq_nr;
- int cpu_index;
-
/*
* Hash the sequence numbers to the cpus by taking
* seq_nr mod. number of cpus in use.
*/
-
- seq_nr = atomic_inc_return(&pd->seq_nr);
- cpu_index = seq_nr % cpumask_weight(pd->cpumask.pcpu);
+ int cpu_index = seq_nr % cpumask_weight(pd->cpumask.pcpu);
return padata_index_to_cpu(pd, cpu_index);
}
+static struct padata_work *padata_work_alloc(void)
+{
+ struct padata_work *pw;
+
+ lockdep_assert_held(&padata_works_lock);
+
+ if (list_empty(&padata_free_works))
+ return NULL; /* No more work items allowed to be queued. */
+
+ pw = list_first_entry(&padata_free_works, struct padata_work, pw_list);
+ list_del(&pw->pw_list);
+ return pw;
+}
+
+static void padata_work_init(struct padata_work *pw, work_func_t work_fn,
+ void *data, int flags)
+{
+ if (flags & PADATA_WORK_ONSTACK)
+ INIT_WORK_ONSTACK(&pw->pw_work, work_fn);
+ else
+ INIT_WORK(&pw->pw_work, work_fn);
+ pw->pw_data = data;
+}
+
+static int __init padata_work_alloc_mt(int nworks, void *data,
+ struct list_head *head)
+{
+ int i;
+
+ spin_lock(&padata_works_lock);
+ /* Start at 1 because the current task participates in the job. */
+ for (i = 1; i < nworks; ++i) {
+ struct padata_work *pw = padata_work_alloc();
+
+ if (!pw)
+ break;
+ padata_work_init(pw, padata_mt_helper, data, 0);
+ list_add(&pw->pw_list, head);
+ }
+ spin_unlock(&padata_works_lock);
+
+ return i;
+}
+
+static void padata_work_free(struct padata_work *pw)
+{
+ lockdep_assert_held(&padata_works_lock);
+ list_add(&pw->pw_list, &padata_free_works);
+}
+
+static void __init padata_works_free(struct list_head *works)
+{
+ struct padata_work *cur, *next;
+
+ if (list_empty(works))
+ return;
+
+ spin_lock(&padata_works_lock);
+ list_for_each_entry_safe(cur, next, works, pw_list) {
+ list_del(&cur->pw_list);
+ padata_work_free(cur);
+ }
+ spin_unlock(&padata_works_lock);
+}
+
static void padata_parallel_worker(struct work_struct *parallel_work)
{
- struct padata_parallel_queue *pqueue;
- LIST_HEAD(local_list);
+ struct padata_work *pw = container_of(parallel_work, struct padata_work,
+ pw_work);
+ struct padata_priv *padata = pw->pw_data;
local_bh_disable();
- pqueue = container_of(parallel_work,
- struct padata_parallel_queue, work);
-
- spin_lock(&pqueue->parallel.lock);
- list_replace_init(&pqueue->parallel.list, &local_list);
- spin_unlock(&pqueue->parallel.lock);
-
- while (!list_empty(&local_list)) {
- struct padata_priv *padata;
-
- padata = list_entry(local_list.next,
- struct padata_priv, list);
-
- list_del_init(&padata->list);
-
- padata->parallel(padata);
- }
-
+ padata->parallel(padata);
+ spin_lock(&padata_works_lock);
+ padata_work_free(pw);
+ spin_unlock(&padata_works_lock);
local_bh_enable();
}
/**
* padata_do_parallel - padata parallelization function
*
- * @pinst: padata instance
+ * @ps: padatashell
* @padata: object to be parallelized
- * @cb_cpu: cpu the serialization callback function will run on,
- * must be in the serial cpumask of padata(i.e. cpumask.cbcpu).
+ * @cb_cpu: pointer to the CPU that the serialization callback function should
+ * run on. If it's not in the serial cpumask of @pinst
+ * (i.e. cpumask.cbcpu), this function selects a fallback CPU and if
+ * none found, returns -EINVAL.
*
* The parallelization callback function will run with BHs off.
* Note: Every object which is parallelized by padata_do_parallel
* must be seen by padata_do_serial.
+ *
+ * Return: 0 on success or else negative error code.
*/
-int padata_do_parallel(struct padata_instance *pinst,
- struct padata_priv *padata, int cb_cpu)
+int padata_do_parallel(struct padata_shell *ps,
+ struct padata_priv *padata, int *cb_cpu)
{
- int target_cpu, err;
- struct padata_parallel_queue *queue;
+ struct padata_instance *pinst = ps->pinst;
+ int i, cpu, cpu_index, err;
struct parallel_data *pd;
+ struct padata_work *pw;
rcu_read_lock_bh();
- pd = rcu_dereference_bh(pinst->pd);
+ pd = rcu_dereference_bh(ps->pd);
err = -EINVAL;
if (!(pinst->flags & PADATA_INIT) || pinst->flags & PADATA_INVALID)
goto out;
- if (!cpumask_test_cpu(cb_cpu, pd->cpumask.cbcpu))
- goto out;
+ if (!cpumask_test_cpu(*cb_cpu, pd->cpumask.cbcpu)) {
+ if (!cpumask_weight(pd->cpumask.cbcpu))
+ goto out;
+
+ /* Select an alternate fallback CPU and notify the caller. */
+ cpu_index = *cb_cpu % cpumask_weight(pd->cpumask.cbcpu);
+
+ cpu = cpumask_first(pd->cpumask.cbcpu);
+ for (i = 0; i < cpu_index; i++)
+ cpu = cpumask_next(cpu, pd->cpumask.cbcpu);
+
+ *cb_cpu = cpu;
+ }
err = -EBUSY;
if ((pinst->flags & PADATA_RESET))
goto out;
- if (atomic_read(&pd->refcnt) >= MAX_OBJ_NUM)
- goto out;
-
- err = 0;
atomic_inc(&pd->refcnt);
padata->pd = pd;
- padata->cb_cpu = cb_cpu;
+ padata->cb_cpu = *cb_cpu;
- target_cpu = padata_cpu_hash(pd);
- padata->cpu = target_cpu;
- queue = per_cpu_ptr(pd->pqueue, target_cpu);
+ spin_lock(&padata_works_lock);
+ padata->seq_nr = ++pd->seq_nr;
+ pw = padata_work_alloc();
+ spin_unlock(&padata_works_lock);
- spin_lock(&queue->parallel.lock);
- list_add_tail(&padata->list, &queue->parallel.list);
- spin_unlock(&queue->parallel.lock);
+ if (!pw) {
+ /* Maximum works limit exceeded, run in the current task. */
+ padata->parallel(padata);
+ }
- queue_work_on(target_cpu, pinst->wq, &queue->work);
+ rcu_read_unlock_bh();
+ if (pw) {
+ padata_work_init(pw, padata_parallel_worker, padata, 0);
+ queue_work(pinst->parallel_wq, &pw->pw_work);
+ }
+
+ return 0;
out:
rcu_read_unlock_bh();
@@ -151,63 +241,58 @@
EXPORT_SYMBOL(padata_do_parallel);
/*
- * padata_get_next - Get the next object that needs serialization.
+ * padata_find_next - Find the next object that needs serialization.
*
- * Return values are:
- *
- * A pointer to the control struct of the next object that needs
- * serialization, if present in one of the percpu reorder queues.
- *
- * -EINPROGRESS, if the next object that needs serialization will
- * be parallel processed by another cpu and is not yet present in
- * the cpu's reorder queue.
- *
- * -ENODATA, if this cpu has to do the parallel processing for
- * the next object.
+ * Return:
+ * * A pointer to the control struct of the next object that needs
+ * serialization, if present in one of the percpu reorder queues.
+ * * NULL, if the next object that needs serialization will
+ * be parallel processed by another cpu and is not yet present in
+ * the cpu's reorder queue.
*/
-static struct padata_priv *padata_get_next(struct parallel_data *pd)
+static struct padata_priv *padata_find_next(struct parallel_data *pd,
+ bool remove_object)
{
- struct padata_parallel_queue *next_queue;
struct padata_priv *padata;
struct padata_list *reorder;
int cpu = pd->cpu;
- next_queue = per_cpu_ptr(pd->pqueue, cpu);
- reorder = &next_queue->reorder;
+ reorder = per_cpu_ptr(pd->reorder_list, cpu);
spin_lock(&reorder->lock);
- if (!list_empty(&reorder->list)) {
- padata = list_entry(reorder->list.next,
- struct padata_priv, list);
-
- list_del_init(&padata->list);
- atomic_dec(&pd->reorder_objects);
-
- pd->cpu = cpumask_next_wrap(cpu, pd->cpumask.pcpu, -1,
- false);
-
+ if (list_empty(&reorder->list)) {
spin_unlock(&reorder->lock);
- goto out;
+ return NULL;
}
+
+ padata = list_entry(reorder->list.next, struct padata_priv, list);
+
+ /*
+ * Checks the rare case where two or more parallel jobs have hashed to
+ * the same CPU and one of the later ones finishes first.
+ */
+ if (padata->seq_nr != pd->processed) {
+ spin_unlock(&reorder->lock);
+ return NULL;
+ }
+
+ if (remove_object) {
+ list_del_init(&padata->list);
+ ++pd->processed;
+ pd->cpu = cpumask_next_wrap(cpu, pd->cpumask.pcpu, -1, false);
+ }
+
spin_unlock(&reorder->lock);
-
- if (__this_cpu_read(pd->pqueue->cpu_index) == next_queue->cpu_index) {
- padata = ERR_PTR(-ENODATA);
- goto out;
- }
-
- padata = ERR_PTR(-EINPROGRESS);
-out:
return padata;
}
static void padata_reorder(struct parallel_data *pd)
{
+ struct padata_instance *pinst = pd->ps->pinst;
int cb_cpu;
struct padata_priv *padata;
struct padata_serial_queue *squeue;
- struct padata_instance *pinst = pd->pinst;
- struct padata_parallel_queue *next_queue;
+ struct padata_list *reorder;
/*
* We need to ensure that only one cpu can work on dequeueing of
@@ -223,25 +308,15 @@
return;
while (1) {
- padata = padata_get_next(pd);
+ padata = padata_find_next(pd, true);
/*
* If the next object that needs serialization is parallel
* processed by another cpu and is still on it's way to the
* cpu's reorder queue, nothing to do for now.
*/
- if (PTR_ERR(padata) == -EINPROGRESS)
+ if (!padata)
break;
-
- /*
- * This cpu has to do the parallel processing of the next
- * object. It's waiting in the cpu's parallelization queue,
- * so exit immediately.
- */
- if (PTR_ERR(padata) == -ENODATA) {
- spin_unlock_bh(&pd->lock);
- return;
- }
cb_cpu = padata->cb_cpu;
squeue = per_cpu_ptr(pd->squeue, cb_cpu);
@@ -250,7 +325,7 @@
list_add_tail(&padata->list, &squeue->serial.list);
spin_unlock(&squeue->serial.lock);
- queue_work_on(cb_cpu, pinst->wq, &squeue->work);
+ queue_work_on(cb_cpu, pinst->serial_wq, &squeue->work);
}
spin_unlock_bh(&pd->lock);
@@ -261,13 +336,13 @@
*
* Ensure reorder queue is read after pd->lock is dropped so we see
* new objects from another task in padata_do_serial. Pairs with
- * smp_mb__after_atomic in padata_do_serial.
+ * smp_mb in padata_do_serial.
*/
smp_mb();
- next_queue = per_cpu_ptr(pd->pqueue, pd->cpu);
- if (!list_empty(&next_queue->reorder.list))
- queue_work(pinst->wq, &pd->reorder_work);
+ reorder = per_cpu_ptr(pd->reorder_list, pd->cpu);
+ if (!list_empty(&reorder->list) && padata_find_next(pd, false))
+ queue_work(pinst->serial_wq, &pd->reorder_work);
}
static void invoke_padata_reorder(struct work_struct *work)
@@ -325,40 +400,139 @@
void padata_do_serial(struct padata_priv *padata)
{
struct parallel_data *pd = padata->pd;
- struct padata_parallel_queue *pqueue = per_cpu_ptr(pd->pqueue,
- padata->cpu);
+ int hashed_cpu = padata_cpu_hash(pd, padata->seq_nr);
+ struct padata_list *reorder = per_cpu_ptr(pd->reorder_list, hashed_cpu);
+ struct padata_priv *cur;
+ struct list_head *pos;
- spin_lock(&pqueue->reorder.lock);
- list_add_tail(&padata->list, &pqueue->reorder.list);
- atomic_inc(&pd->reorder_objects);
- spin_unlock(&pqueue->reorder.lock);
+ spin_lock(&reorder->lock);
+ /* Sort in ascending order of sequence number. */
+ list_for_each_prev(pos, &reorder->list) {
+ cur = list_entry(pos, struct padata_priv, list);
+ if (cur->seq_nr < padata->seq_nr)
+ break;
+ }
+ list_add(&padata->list, pos);
+ spin_unlock(&reorder->lock);
/*
* Ensure the addition to the reorder list is ordered correctly
* with the trylock of pd->lock in padata_reorder. Pairs with smp_mb
* in padata_reorder.
*/
- smp_mb__after_atomic();
+ smp_mb();
padata_reorder(pd);
}
EXPORT_SYMBOL(padata_do_serial);
-static int padata_setup_cpumasks(struct parallel_data *pd,
- const struct cpumask *pcpumask,
- const struct cpumask *cbcpumask)
+static int padata_setup_cpumasks(struct padata_instance *pinst)
{
- if (!alloc_cpumask_var(&pd->cpumask.pcpu, GFP_KERNEL))
+ struct workqueue_attrs *attrs;
+ int err;
+
+ attrs = alloc_workqueue_attrs();
+ if (!attrs)
return -ENOMEM;
- cpumask_and(pd->cpumask.pcpu, pcpumask, cpu_online_mask);
- if (!alloc_cpumask_var(&pd->cpumask.cbcpu, GFP_KERNEL)) {
- free_cpumask_var(pd->cpumask.pcpu);
- return -ENOMEM;
+ /* Restrict parallel_wq workers to pd->cpumask.pcpu. */
+ cpumask_copy(attrs->cpumask, pinst->cpumask.pcpu);
+ err = apply_workqueue_attrs(pinst->parallel_wq, attrs);
+ free_workqueue_attrs(attrs);
+
+ return err;
+}
+
+static void __init padata_mt_helper(struct work_struct *w)
+{
+ struct padata_work *pw = container_of(w, struct padata_work, pw_work);
+ struct padata_mt_job_state *ps = pw->pw_data;
+ struct padata_mt_job *job = ps->job;
+ bool done;
+
+ spin_lock(&ps->lock);
+
+ while (job->size > 0) {
+ unsigned long start, size, end;
+
+ start = job->start;
+ /* So end is chunk size aligned if enough work remains. */
+ size = roundup(start + 1, ps->chunk_size) - start;
+ size = min(size, job->size);
+ end = start + size;
+
+ job->start = end;
+ job->size -= size;
+
+ spin_unlock(&ps->lock);
+ job->thread_fn(start, end, job->fn_arg);
+ spin_lock(&ps->lock);
}
- cpumask_and(pd->cpumask.cbcpu, cbcpumask, cpu_online_mask);
- return 0;
+ ++ps->nworks_fini;
+ done = (ps->nworks_fini == ps->nworks);
+ spin_unlock(&ps->lock);
+
+ if (done)
+ complete(&ps->completion);
+}
+
+/**
+ * padata_do_multithreaded - run a multithreaded job
+ * @job: Description of the job.
+ *
+ * See the definition of struct padata_mt_job for more details.
+ */
+void __init padata_do_multithreaded(struct padata_mt_job *job)
+{
+ /* In case threads finish at different times. */
+ static const unsigned long load_balance_factor = 4;
+ struct padata_work my_work, *pw;
+ struct padata_mt_job_state ps;
+ LIST_HEAD(works);
+ int nworks;
+
+ if (job->size == 0)
+ return;
+
+ /* Ensure at least one thread when size < min_chunk. */
+ nworks = max(job->size / job->min_chunk, 1ul);
+ nworks = min(nworks, job->max_threads);
+
+ if (nworks == 1) {
+ /* Single thread, no coordination needed, cut to the chase. */
+ job->thread_fn(job->start, job->start + job->size, job->fn_arg);
+ return;
+ }
+
+ spin_lock_init(&ps.lock);
+ init_completion(&ps.completion);
+ ps.job = job;
+ ps.nworks = padata_work_alloc_mt(nworks, &ps, &works);
+ ps.nworks_fini = 0;
+
+ /*
+ * Chunk size is the amount of work a helper does per call to the
+ * thread function. Load balance large jobs between threads by
+ * increasing the number of chunks, guarantee at least the minimum
+ * chunk size from the caller, and honor the caller's alignment.
+ */
+ ps.chunk_size = job->size / (ps.nworks * load_balance_factor);
+ ps.chunk_size = max(ps.chunk_size, job->min_chunk);
+ ps.chunk_size = roundup(ps.chunk_size, job->align);
+
+ list_for_each_entry(pw, &works, pw_list)
+ queue_work(system_unbound_wq, &pw->pw_work);
+
+ /* Use the current thread, which saves starting a workqueue worker. */
+ padata_work_init(&my_work, padata_mt_helper, &ps, PADATA_WORK_ONSTACK);
+ padata_mt_helper(&my_work.pw_work);
+
+ /* Wait for all the helpers to finish. */
+ wait_for_completion(&ps.completion);
+
+ destroy_work_on_stack(&my_work.pw_work);
+ padata_works_free(&works);
}
static void __padata_list_init(struct padata_list *pd_list)
@@ -381,68 +555,62 @@
}
}
-/* Initialize all percpu queues used by parallel workers */
-static void padata_init_pqueues(struct parallel_data *pd)
+/* Initialize per-CPU reorder lists */
+static void padata_init_reorder_list(struct parallel_data *pd)
{
- int cpu_index, cpu;
- struct padata_parallel_queue *pqueue;
+ int cpu;
+ struct padata_list *list;
- cpu_index = 0;
- for_each_possible_cpu(cpu) {
- pqueue = per_cpu_ptr(pd->pqueue, cpu);
-
- if (!cpumask_test_cpu(cpu, pd->cpumask.pcpu)) {
- pqueue->cpu_index = -1;
- continue;
- }
-
- pqueue->cpu_index = cpu_index;
- cpu_index++;
-
- __padata_list_init(&pqueue->reorder);
- __padata_list_init(&pqueue->parallel);
- INIT_WORK(&pqueue->work, padata_parallel_worker);
- atomic_set(&pqueue->num_obj, 0);
+ for_each_cpu(cpu, pd->cpumask.pcpu) {
+ list = per_cpu_ptr(pd->reorder_list, cpu);
+ __padata_list_init(list);
}
}
/* Allocate and initialize the internal cpumask dependend resources. */
-static struct parallel_data *padata_alloc_pd(struct padata_instance *pinst,
- const struct cpumask *pcpumask,
- const struct cpumask *cbcpumask)
+static struct parallel_data *padata_alloc_pd(struct padata_shell *ps)
{
+ struct padata_instance *pinst = ps->pinst;
struct parallel_data *pd;
pd = kzalloc(sizeof(struct parallel_data), GFP_KERNEL);
if (!pd)
goto err;
- pd->pqueue = alloc_percpu(struct padata_parallel_queue);
- if (!pd->pqueue)
+ pd->reorder_list = alloc_percpu(struct padata_list);
+ if (!pd->reorder_list)
goto err_free_pd;
pd->squeue = alloc_percpu(struct padata_serial_queue);
if (!pd->squeue)
- goto err_free_pqueue;
- if (padata_setup_cpumasks(pd, pcpumask, cbcpumask) < 0)
- goto err_free_squeue;
+ goto err_free_reorder_list;
- padata_init_pqueues(pd);
+ pd->ps = ps;
+
+ if (!alloc_cpumask_var(&pd->cpumask.pcpu, GFP_KERNEL))
+ goto err_free_squeue;
+ if (!alloc_cpumask_var(&pd->cpumask.cbcpu, GFP_KERNEL))
+ goto err_free_pcpu;
+
+ cpumask_and(pd->cpumask.pcpu, pinst->cpumask.pcpu, cpu_online_mask);
+ cpumask_and(pd->cpumask.cbcpu, pinst->cpumask.cbcpu, cpu_online_mask);
+
+ padata_init_reorder_list(pd);
padata_init_squeues(pd);
- atomic_set(&pd->seq_nr, -1);
- atomic_set(&pd->reorder_objects, 0);
+ pd->seq_nr = -1;
atomic_set(&pd->refcnt, 1);
- pd->pinst = pinst;
spin_lock_init(&pd->lock);
pd->cpu = cpumask_first(pd->cpumask.pcpu);
INIT_WORK(&pd->reorder_work, invoke_padata_reorder);
return pd;
+err_free_pcpu:
+ free_cpumask_var(pd->cpumask.pcpu);
err_free_squeue:
free_percpu(pd->squeue);
-err_free_pqueue:
- free_percpu(pd->pqueue);
+err_free_reorder_list:
+ free_percpu(pd->reorder_list);
err_free_pd:
kfree(pd);
err:
@@ -453,7 +621,7 @@
{
free_cpumask_var(pd->cpumask.pcpu);
free_cpumask_var(pd->cpumask.cbcpu);
- free_percpu(pd->pqueue);
+ free_percpu(pd->reorder_list);
free_percpu(pd->squeue);
kfree(pd);
}
@@ -474,65 +642,43 @@
}
/* Replace the internal control structure with a new one. */
-static void padata_replace(struct padata_instance *pinst,
- struct parallel_data *pd_new)
+static int padata_replace_one(struct padata_shell *ps)
{
- struct parallel_data *pd_old = pinst->pd;
- int notification_mask = 0;
+ struct parallel_data *pd_new;
+
+ pd_new = padata_alloc_pd(ps);
+ if (!pd_new)
+ return -ENOMEM;
+
+ ps->opd = rcu_dereference_protected(ps->pd, 1);
+ rcu_assign_pointer(ps->pd, pd_new);
+
+ return 0;
+}
+
+static int padata_replace(struct padata_instance *pinst)
+{
+ struct padata_shell *ps;
+ int err = 0;
pinst->flags |= PADATA_RESET;
- rcu_assign_pointer(pinst->pd, pd_new);
+ list_for_each_entry(ps, &pinst->pslist, list) {
+ err = padata_replace_one(ps);
+ if (err)
+ break;
+ }
synchronize_rcu();
- if (!cpumask_equal(pd_old->cpumask.pcpu, pd_new->cpumask.pcpu))
- notification_mask |= PADATA_CPU_PARALLEL;
- if (!cpumask_equal(pd_old->cpumask.cbcpu, pd_new->cpumask.cbcpu))
- notification_mask |= PADATA_CPU_SERIAL;
-
- if (atomic_dec_and_test(&pd_old->refcnt))
- padata_free_pd(pd_old);
-
- if (notification_mask)
- blocking_notifier_call_chain(&pinst->cpumask_change_notifier,
- notification_mask,
- &pd_new->cpumask);
+ list_for_each_entry_continue_reverse(ps, &pinst->pslist, list)
+ if (atomic_dec_and_test(&ps->opd->refcnt))
+ padata_free_pd(ps->opd);
pinst->flags &= ~PADATA_RESET;
-}
-/**
- * padata_register_cpumask_notifier - Registers a notifier that will be called
- * if either pcpu or cbcpu or both cpumasks change.
- *
- * @pinst: A poineter to padata instance
- * @nblock: A pointer to notifier block.
- */
-int padata_register_cpumask_notifier(struct padata_instance *pinst,
- struct notifier_block *nblock)
-{
- return blocking_notifier_chain_register(&pinst->cpumask_change_notifier,
- nblock);
+ return err;
}
-EXPORT_SYMBOL(padata_register_cpumask_notifier);
-
-/**
- * padata_unregister_cpumask_notifier - Unregisters cpumask notifier
- * registered earlier using padata_register_cpumask_notifier
- *
- * @pinst: A pointer to data instance.
- * @nlock: A pointer to notifier block.
- */
-int padata_unregister_cpumask_notifier(struct padata_instance *pinst,
- struct notifier_block *nblock)
-{
- return blocking_notifier_chain_unregister(
- &pinst->cpumask_change_notifier,
- nblock);
-}
-EXPORT_SYMBOL(padata_unregister_cpumask_notifier);
-
/* If cpumask contains no active cpu, we mark the instance as invalid. */
static bool padata_validate_cpumask(struct padata_instance *pinst,
@@ -552,7 +698,7 @@
cpumask_var_t cbcpumask)
{
int valid;
- struct parallel_data *pd;
+ int err;
valid = padata_validate_cpumask(pinst, pcpumask);
if (!valid) {
@@ -565,29 +711,26 @@
__padata_stop(pinst);
out_replace:
- pd = padata_alloc_pd(pinst, pcpumask, cbcpumask);
- if (!pd)
- return -ENOMEM;
-
cpumask_copy(pinst->cpumask.pcpu, pcpumask);
cpumask_copy(pinst->cpumask.cbcpu, cbcpumask);
- padata_replace(pinst, pd);
+ err = padata_setup_cpumasks(pinst) ?: padata_replace(pinst);
if (valid)
__padata_start(pinst);
- return 0;
+ return err;
}
/**
- * padata_set_cpumask: Sets specified by @cpumask_type cpumask to the value
- * equivalent to @cpumask.
- *
+ * padata_set_cpumask - Sets specified by @cpumask_type cpumask to the value
+ * equivalent to @cpumask.
* @pinst: padata instance
* @cpumask_type: PADATA_CPU_SERIAL or PADATA_CPU_PARALLEL corresponding
* to parallel and serial cpumasks respectively.
* @cpumask: the cpumask to use
+ *
+ * Return: 0 on success or negative error code
*/
int padata_set_cpumask(struct padata_instance *pinst, int cpumask_type,
cpumask_var_t cpumask)
@@ -621,121 +764,37 @@
}
EXPORT_SYMBOL(padata_set_cpumask);
-/**
- * padata_start - start the parallel processing
- *
- * @pinst: padata instance to start
- */
-int padata_start(struct padata_instance *pinst)
-{
- int err = 0;
-
- mutex_lock(&pinst->lock);
-
- if (pinst->flags & PADATA_INVALID)
- err = -EINVAL;
-
- __padata_start(pinst);
-
- mutex_unlock(&pinst->lock);
-
- return err;
-}
-EXPORT_SYMBOL(padata_start);
-
-/**
- * padata_stop - stop the parallel processing
- *
- * @pinst: padata instance to stop
- */
-void padata_stop(struct padata_instance *pinst)
-{
- mutex_lock(&pinst->lock);
- __padata_stop(pinst);
- mutex_unlock(&pinst->lock);
-}
-EXPORT_SYMBOL(padata_stop);
-
#ifdef CONFIG_HOTPLUG_CPU
static int __padata_add_cpu(struct padata_instance *pinst, int cpu)
{
- struct parallel_data *pd;
+ int err = 0;
if (cpumask_test_cpu(cpu, cpu_online_mask)) {
- pd = padata_alloc_pd(pinst, pinst->cpumask.pcpu,
- pinst->cpumask.cbcpu);
- if (!pd)
- return -ENOMEM;
-
- padata_replace(pinst, pd);
+ err = padata_replace(pinst);
if (padata_validate_cpumask(pinst, pinst->cpumask.pcpu) &&
padata_validate_cpumask(pinst, pinst->cpumask.cbcpu))
__padata_start(pinst);
}
- return 0;
+ return err;
}
static int __padata_remove_cpu(struct padata_instance *pinst, int cpu)
{
- struct parallel_data *pd = NULL;
+ int err = 0;
- if (cpumask_test_cpu(cpu, cpu_online_mask)) {
-
+ if (!cpumask_test_cpu(cpu, cpu_online_mask)) {
if (!padata_validate_cpumask(pinst, pinst->cpumask.pcpu) ||
!padata_validate_cpumask(pinst, pinst->cpumask.cbcpu))
__padata_stop(pinst);
- pd = padata_alloc_pd(pinst, pinst->cpumask.pcpu,
- pinst->cpumask.cbcpu);
- if (!pd)
- return -ENOMEM;
-
- padata_replace(pinst, pd);
-
- cpumask_clear_cpu(cpu, pd->cpumask.cbcpu);
- cpumask_clear_cpu(cpu, pd->cpumask.pcpu);
+ err = padata_replace(pinst);
}
-
- return 0;
-}
-
- /**
- * padata_remove_cpu - remove a cpu from the one or both(serial and parallel)
- * padata cpumasks.
- *
- * @pinst: padata instance
- * @cpu: cpu to remove
- * @mask: bitmask specifying from which cpumask @cpu should be removed
- * The @mask may be any combination of the following flags:
- * PADATA_CPU_SERIAL - serial cpumask
- * PADATA_CPU_PARALLEL - parallel cpumask
- */
-int padata_remove_cpu(struct padata_instance *pinst, int cpu, int mask)
-{
- int err;
-
- if (!(mask & (PADATA_CPU_SERIAL | PADATA_CPU_PARALLEL)))
- return -EINVAL;
-
- mutex_lock(&pinst->lock);
-
- get_online_cpus();
- if (mask & PADATA_CPU_SERIAL)
- cpumask_clear_cpu(cpu, pinst->cpumask.cbcpu);
- if (mask & PADATA_CPU_PARALLEL)
- cpumask_clear_cpu(cpu, pinst->cpumask.pcpu);
-
- err = __padata_remove_cpu(pinst, cpu);
- put_online_cpus();
-
- mutex_unlock(&pinst->lock);
return err;
}
-EXPORT_SYMBOL(padata_remove_cpu);
static inline int pinst_has_cpu(struct padata_instance *pinst, int cpu)
{
@@ -748,7 +807,7 @@
struct padata_instance *pinst;
int ret;
- pinst = hlist_entry_safe(node, struct padata_instance, node);
+ pinst = hlist_entry_safe(node, struct padata_instance, cpu_online_node);
if (!pinst_has_cpu(pinst, cpu))
return 0;
@@ -758,12 +817,12 @@
return ret;
}
-static int padata_cpu_prep_down(unsigned int cpu, struct hlist_node *node)
+static int padata_cpu_dead(unsigned int cpu, struct hlist_node *node)
{
struct padata_instance *pinst;
int ret;
- pinst = hlist_entry_safe(node, struct padata_instance, node);
+ pinst = hlist_entry_safe(node, struct padata_instance, cpu_dead_node);
if (!pinst_has_cpu(pinst, cpu))
return 0;
@@ -779,13 +838,17 @@
static void __padata_free(struct padata_instance *pinst)
{
#ifdef CONFIG_HOTPLUG_CPU
- cpuhp_state_remove_instance_nocalls(hp_online, &pinst->node);
+ cpuhp_state_remove_instance_nocalls(CPUHP_PADATA_DEAD,
+ &pinst->cpu_dead_node);
+ cpuhp_state_remove_instance_nocalls(hp_online, &pinst->cpu_online_node);
#endif
- padata_stop(pinst);
- padata_free_pd(pinst->pd);
+ WARN_ON(!list_empty(&pinst->pslist));
+
free_cpumask_var(pinst->cpumask.pcpu);
free_cpumask_var(pinst->cpumask.cbcpu);
+ destroy_workqueue(pinst->serial_wq);
+ destroy_workqueue(pinst->parallel_wq);
kfree(pinst);
}
@@ -872,6 +935,7 @@
¶llel_cpumask_attr.attr,
NULL,
};
+ATTRIBUTE_GROUPS(padata_default);
static ssize_t padata_sysfs_show(struct kobject *kobj,
struct attribute *attr, char *buf)
@@ -910,92 +974,86 @@
static struct kobj_type padata_attr_type = {
.sysfs_ops = &padata_sysfs_ops,
- .default_attrs = padata_default_attrs,
+ .default_groups = padata_default_groups,
.release = padata_sysfs_release,
};
/**
- * padata_alloc - allocate and initialize a padata instance and specify
- * cpumasks for serial and parallel workers.
+ * padata_alloc - allocate and initialize a padata instance
+ * @name: used to identify the instance
*
- * @wq: workqueue to use for the allocated padata instance
- * @pcpumask: cpumask that will be used for padata parallelization
- * @cbcpumask: cpumask that will be used for padata serialization
- *
- * Must be called from a cpus_read_lock() protected region
+ * Return: new instance on success, NULL on error
*/
-static struct padata_instance *padata_alloc(struct workqueue_struct *wq,
- const struct cpumask *pcpumask,
- const struct cpumask *cbcpumask)
+struct padata_instance *padata_alloc(const char *name)
{
struct padata_instance *pinst;
- struct parallel_data *pd = NULL;
pinst = kzalloc(sizeof(struct padata_instance), GFP_KERNEL);
if (!pinst)
goto err;
- if (!alloc_cpumask_var(&pinst->cpumask.pcpu, GFP_KERNEL))
+ pinst->parallel_wq = alloc_workqueue("%s_parallel", WQ_UNBOUND, 0,
+ name);
+ if (!pinst->parallel_wq)
goto err_free_inst;
+
+ get_online_cpus();
+
+ pinst->serial_wq = alloc_workqueue("%s_serial", WQ_MEM_RECLAIM |
+ WQ_CPU_INTENSIVE, 1, name);
+ if (!pinst->serial_wq)
+ goto err_put_cpus;
+
+ if (!alloc_cpumask_var(&pinst->cpumask.pcpu, GFP_KERNEL))
+ goto err_free_serial_wq;
if (!alloc_cpumask_var(&pinst->cpumask.cbcpu, GFP_KERNEL)) {
free_cpumask_var(pinst->cpumask.pcpu);
- goto err_free_inst;
+ goto err_free_serial_wq;
}
- if (!padata_validate_cpumask(pinst, pcpumask) ||
- !padata_validate_cpumask(pinst, cbcpumask))
+
+ INIT_LIST_HEAD(&pinst->pslist);
+
+ cpumask_copy(pinst->cpumask.pcpu, cpu_possible_mask);
+ cpumask_copy(pinst->cpumask.cbcpu, cpu_possible_mask);
+
+ if (padata_setup_cpumasks(pinst))
goto err_free_masks;
- pd = padata_alloc_pd(pinst, pcpumask, cbcpumask);
- if (!pd)
- goto err_free_masks;
+ __padata_start(pinst);
- rcu_assign_pointer(pinst->pd, pd);
-
- pinst->wq = wq;
-
- cpumask_copy(pinst->cpumask.pcpu, pcpumask);
- cpumask_copy(pinst->cpumask.cbcpu, cbcpumask);
-
- pinst->flags = 0;
-
- BLOCKING_INIT_NOTIFIER_HEAD(&pinst->cpumask_change_notifier);
kobject_init(&pinst->kobj, &padata_attr_type);
mutex_init(&pinst->lock);
#ifdef CONFIG_HOTPLUG_CPU
- cpuhp_state_add_instance_nocalls_cpuslocked(hp_online, &pinst->node);
+ cpuhp_state_add_instance_nocalls_cpuslocked(hp_online,
+ &pinst->cpu_online_node);
+ cpuhp_state_add_instance_nocalls_cpuslocked(CPUHP_PADATA_DEAD,
+ &pinst->cpu_dead_node);
#endif
+
+ put_online_cpus();
+
return pinst;
err_free_masks:
free_cpumask_var(pinst->cpumask.pcpu);
free_cpumask_var(pinst->cpumask.cbcpu);
+err_free_serial_wq:
+ destroy_workqueue(pinst->serial_wq);
+err_put_cpus:
+ put_online_cpus();
+ destroy_workqueue(pinst->parallel_wq);
err_free_inst:
kfree(pinst);
err:
return NULL;
}
-
-/**
- * padata_alloc_possible - Allocate and initialize padata instance.
- * Use the cpu_possible_mask for serial and
- * parallel workers.
- *
- * @wq: workqueue to use for the allocated padata instance
- *
- * Must be called from a cpus_read_lock() protected region
- */
-struct padata_instance *padata_alloc_possible(struct workqueue_struct *wq)
-{
- lockdep_assert_cpus_held();
- return padata_alloc(wq, cpu_possible_mask, cpu_possible_mask);
-}
-EXPORT_SYMBOL(padata_alloc_possible);
+EXPORT_SYMBOL(padata_alloc);
/**
* padata_free - free a padata instance
*
- * @padata_inst: padata instance to free
+ * @pinst: padata instance to free
*/
void padata_free(struct padata_instance *pinst)
{
@@ -1003,25 +1061,99 @@
}
EXPORT_SYMBOL(padata_free);
-#ifdef CONFIG_HOTPLUG_CPU
-
-static __init int padata_driver_init(void)
+/**
+ * padata_alloc_shell - Allocate and initialize padata shell.
+ *
+ * @pinst: Parent padata_instance object.
+ *
+ * Return: new shell on success, NULL on error
+ */
+struct padata_shell *padata_alloc_shell(struct padata_instance *pinst)
{
+ struct parallel_data *pd;
+ struct padata_shell *ps;
+
+ ps = kzalloc(sizeof(*ps), GFP_KERNEL);
+ if (!ps)
+ goto out;
+
+ ps->pinst = pinst;
+
+ get_online_cpus();
+ pd = padata_alloc_pd(ps);
+ put_online_cpus();
+
+ if (!pd)
+ goto out_free_ps;
+
+ mutex_lock(&pinst->lock);
+ RCU_INIT_POINTER(ps->pd, pd);
+ list_add(&ps->list, &pinst->pslist);
+ mutex_unlock(&pinst->lock);
+
+ return ps;
+
+out_free_ps:
+ kfree(ps);
+out:
+ return NULL;
+}
+EXPORT_SYMBOL(padata_alloc_shell);
+
+/**
+ * padata_free_shell - free a padata shell
+ *
+ * @ps: padata shell to free
+ */
+void padata_free_shell(struct padata_shell *ps)
+{
+ if (!ps)
+ return;
+
+ mutex_lock(&ps->pinst->lock);
+ list_del(&ps->list);
+ padata_free_pd(rcu_dereference_protected(ps->pd, 1));
+ mutex_unlock(&ps->pinst->lock);
+
+ kfree(ps);
+}
+EXPORT_SYMBOL(padata_free_shell);
+
+void __init padata_init(void)
+{
+ unsigned int i, possible_cpus;
+#ifdef CONFIG_HOTPLUG_CPU
int ret;
ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "padata:online",
- padata_cpu_online,
- padata_cpu_prep_down);
+ padata_cpu_online, NULL);
if (ret < 0)
- return ret;
+ goto err;
hp_online = ret;
- return 0;
-}
-module_init(padata_driver_init);
-static __exit void padata_driver_exit(void)
-{
- cpuhp_remove_multi_state(hp_online);
-}
-module_exit(padata_driver_exit);
+ ret = cpuhp_setup_state_multi(CPUHP_PADATA_DEAD, "padata:dead",
+ NULL, padata_cpu_dead);
+ if (ret < 0)
+ goto remove_online_state;
#endif
+
+ possible_cpus = num_possible_cpus();
+ padata_works = kmalloc_array(possible_cpus, sizeof(struct padata_work),
+ GFP_KERNEL);
+ if (!padata_works)
+ goto remove_dead_state;
+
+ for (i = 0; i < possible_cpus; ++i)
+ list_add(&padata_works[i].pw_list, &padata_free_works);
+
+ return;
+
+remove_dead_state:
+#ifdef CONFIG_HOTPLUG_CPU
+ cpuhp_remove_multi_state(CPUHP_PADATA_DEAD);
+remove_online_state:
+ cpuhp_remove_multi_state(hp_online);
+err:
+#endif
+ pr_warn("padata: initialization failed\n");
+}
--
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