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authorLinus Torvalds <torvalds@linux-foundation.org>2020-06-03 20:24:15 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-06-03 20:24:15 -0700
commitee01c4d72adffb7d424535adf630f2955748fa8b (patch)
tree9ea9f40473e105e936e7477ab7dc7248d899af21 /kernel
parentc444eb564fb16645c172d550359cb3d75fe8a040 (diff)
parent09587a09ada2ed7c39aedfa2681152b5ac5641ee (diff)
Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton: "More mm/ work, plenty more to come Subsystems affected by this patch series: slub, memcg, gup, kasan, pagealloc, hugetlb, vmscan, tools, mempolicy, memblock, hugetlbfs, thp, mmap, kconfig" * akpm: (131 commits) arm64: mm: use ARCH_HAS_DEBUG_WX instead of arch defined x86: mm: use ARCH_HAS_DEBUG_WX instead of arch defined riscv: support DEBUG_WX mm: add DEBUG_WX support drivers/base/memory.c: cache memory blocks in xarray to accelerate lookup mm/thp: rename pmd_mknotpresent() as pmd_mkinvalid() powerpc/mm: drop platform defined pmd_mknotpresent() mm: thp: don't need to drain lru cache when splitting and mlocking THP hugetlbfs: get unmapped area below TASK_UNMAPPED_BASE for hugetlbfs sparc32: register memory occupied by kernel as memblock.memory include/linux/memblock.h: fix minor typo and unclear comment mm, mempolicy: fix up gup usage in lookup_node tools/vm/page_owner_sort.c: filter out unneeded line mm: swap: memcg: fix memcg stats for huge pages mm: swap: fix vmstats for huge pages mm: vmscan: limit the range of LRU type balancing mm: vmscan: reclaim writepage is IO cost mm: vmscan: determine anon/file pressure balance at the reclaim root mm: balance LRU lists based on relative thrashing mm: only count actual rotations as LRU reclaim cost ...
Diffstat (limited to 'kernel')
-rw-r--r--kernel/events/uprobes.c10
-rw-r--r--kernel/padata.c277
-rw-r--r--kernel/sysctl.c3
3 files changed, 230 insertions, 60 deletions
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index ece7e13f6e4a..eddc8db96027 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -162,14 +162,12 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
};
int err;
struct mmu_notifier_range range;
- struct mem_cgroup *memcg;
mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma, mm, addr,
addr + PAGE_SIZE);
if (new_page) {
- err = mem_cgroup_try_charge(new_page, vma->vm_mm, GFP_KERNEL,
- &memcg, false);
+ err = mem_cgroup_charge(new_page, vma->vm_mm, GFP_KERNEL);
if (err)
return err;
}
@@ -179,17 +177,13 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
mmu_notifier_invalidate_range_start(&range);
err = -EAGAIN;
- if (!page_vma_mapped_walk(&pvmw)) {
- if (new_page)
- mem_cgroup_cancel_charge(new_page, memcg, false);
+ if (!page_vma_mapped_walk(&pvmw))
goto unlock;
- }
VM_BUG_ON_PAGE(addr != pvmw.address, old_page);
if (new_page) {
get_page(new_page);
page_add_new_anon_rmap(new_page, vma, addr, false);
- mem_cgroup_commit_charge(new_page, memcg, false, false);
lru_cache_add_active_or_unevictable(new_page, vma);
} else
/* no new page, just dec_mm_counter for old_page */
diff --git a/kernel/padata.c b/kernel/padata.c
index aae789896616..29fc5d87a4cd 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -7,6 +7,9 @@
* 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,
* version 2, as published by the Free Software Foundation.
@@ -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)
{
@@ -59,30 +82,82 @@ static int padata_cpu_hash(struct parallel_data *pd, unsigned int seq_nr)
return padata_index_to_cpu(pd, cpu_index);
}
-static void padata_parallel_worker(struct work_struct *parallel_work)
+static struct padata_work *padata_work_alloc(void)
{
- struct padata_parallel_queue *pqueue;
- LIST_HEAD(local_list);
+ struct padata_work *pw;
- local_bh_disable();
- pqueue = container_of(parallel_work,
- struct padata_parallel_queue, work);
+ lockdep_assert_held(&padata_works_lock);
- spin_lock(&pqueue->parallel.lock);
- list_replace_init(&pqueue->parallel.list, &local_list);
- spin_unlock(&pqueue->parallel.lock);
+ if (list_empty(&padata_free_works))
+ return NULL; /* No more work items allowed to be queued. */
- while (!list_empty(&local_list)) {
- struct padata_priv *padata;
+ pw = list_first_entry(&padata_free_works, struct padata_work, pw_list);
+ list_del(&pw->pw_list);
+ return pw;
+}
- padata = list_entry(local_list.next,
- struct padata_priv, list);
+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;
+}
- list_del_init(&padata->list);
+static int __init padata_work_alloc_mt(int nworks, void *data,
+ struct list_head *head)
+{
+ int i;
- padata->parallel(padata);
+ 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_work *pw = container_of(parallel_work, struct padata_work,
+ pw_work);
+ struct padata_priv *padata = pw->pw_data;
+
+ local_bh_disable();
+ padata->parallel(padata);
+ spin_lock(&padata_works_lock);
+ padata_work_free(pw);
+ spin_unlock(&padata_works_lock);
local_bh_enable();
}
@@ -106,9 +181,9 @@ int padata_do_parallel(struct padata_shell *ps,
struct padata_priv *padata, int *cb_cpu)
{
struct padata_instance *pinst = ps->pinst;
- int i, cpu, cpu_index, target_cpu, err;
- struct padata_parallel_queue *queue;
+ int i, cpu, cpu_index, err;
struct parallel_data *pd;
+ struct padata_work *pw;
rcu_read_lock_bh();
@@ -136,25 +211,25 @@ int padata_do_parallel(struct padata_shell *ps,
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->seq_nr = atomic_inc_return(&pd->seq_nr);
- target_cpu = padata_cpu_hash(pd, padata->seq_nr);
- padata->cpu = target_cpu;
- queue = per_cpu_ptr(pd->pqueue, target_cpu);
-
- spin_lock(&queue->parallel.lock);
- list_add_tail(&padata->list, &queue->parallel.list);
- spin_unlock(&queue->parallel.lock);
+ rcu_read_unlock_bh();
- queue_work(pinst->parallel_wq, &queue->work);
+ spin_lock(&padata_works_lock);
+ padata->seq_nr = ++pd->seq_nr;
+ pw = padata_work_alloc();
+ spin_unlock(&padata_works_lock);
+ if (pw) {
+ padata_work_init(pw, padata_parallel_worker, padata, 0);
+ queue_work(pinst->parallel_wq, &pw->pw_work);
+ } else {
+ /* Maximum works limit exceeded, run in the current task. */
+ padata->parallel(padata);
+ }
+ return 0;
out:
rcu_read_unlock_bh();
@@ -325,8 +400,9 @@ static void padata_serial_worker(struct work_struct *serial_work)
void padata_do_serial(struct padata_priv *padata)
{
struct parallel_data *pd = padata->pd;
+ int hashed_cpu = padata_cpu_hash(pd, padata->seq_nr);
struct padata_parallel_queue *pqueue = per_cpu_ptr(pd->pqueue,
- padata->cpu);
+ hashed_cpu);
struct padata_priv *cur;
spin_lock(&pqueue->reorder.lock);
@@ -387,6 +463,98 @@ out:
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);
+ }
+
+ ++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)
{
INIT_LIST_HEAD(&pd_list->list);
@@ -417,8 +585,6 @@ static void padata_init_pqueues(struct parallel_data *pd)
pqueue = per_cpu_ptr(pd->pqueue, cpu);
__padata_list_init(&pqueue->reorder);
- __padata_list_init(&pqueue->parallel);
- INIT_WORK(&pqueue->work, padata_parallel_worker);
atomic_set(&pqueue->num_obj, 0);
}
}
@@ -452,7 +618,7 @@ static struct parallel_data *padata_alloc_pd(struct padata_shell *ps)
padata_init_pqueues(pd);
padata_init_squeues(pd);
- atomic_set(&pd->seq_nr, -1);
+ pd->seq_nr = -1;
atomic_set(&pd->refcnt, 1);
spin_lock_init(&pd->lock);
pd->cpu = cpumask_first(pd->cpumask.pcpu);
@@ -1052,32 +1218,41 @@ void padata_free_shell(struct padata_shell *ps)
}
EXPORT_SYMBOL(padata_free_shell);
-#ifdef CONFIG_HOTPLUG_CPU
-
-static __init int padata_driver_init(void)
+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, NULL);
if (ret < 0)
- return ret;
+ goto err;
hp_online = ret;
ret = cpuhp_setup_state_multi(CPUHP_PADATA_DEAD, "padata:dead",
NULL, padata_cpu_dead);
- if (ret < 0) {
- cpuhp_remove_multi_state(hp_online);
- return ret;
- }
- return 0;
-}
-module_init(padata_driver_init);
+ if (ret < 0)
+ goto remove_online_state;
+#endif
-static __exit void padata_driver_exit(void)
-{
+ 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);
-}
-module_exit(padata_driver_exit);
+err:
#endif
+ pr_warn("padata: initialization failed\n");
+}
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 7efe0d499c1d..715774d8c55f 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -118,6 +118,7 @@ static unsigned long zero_ul;
static unsigned long one_ul = 1;
static unsigned long long_max = LONG_MAX;
static int one_hundred = 100;
+static int two_hundred = 200;
static int one_thousand = 1000;
#ifdef CONFIG_PRINTK
static int ten_thousand = 10000;
@@ -2732,7 +2733,7 @@ static struct ctl_table vm_table[] = {
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = SYSCTL_ZERO,
- .extra2 = &one_hundred,
+ .extra2 = &two_hundred,
},
#ifdef CONFIG_HUGETLB_PAGE
{