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-rw-r--r--kernel/exit.c9
-rw-r--r--kernel/fork.c1
-rw-r--r--kernel/irq/proc.c2
-rw-r--r--kernel/kthread.c11
-rw-r--r--kernel/perf_event.c37
-rw-r--r--kernel/power/hibernate.c22
-rw-r--r--kernel/power/suspend.c5
-rw-r--r--kernel/power/swap.c55
-rw-r--r--kernel/power/user.c4
-rw-r--r--kernel/printk.c4
-rw-r--r--kernel/resource.c104
-rw-r--r--kernel/sched.c287
-rw-r--r--kernel/taskstats.c57
-rw-r--r--kernel/timer.c8
-rw-r--r--kernel/trace/ring_buffer.c9
-rw-r--r--kernel/trace/trace.c10
-rw-r--r--kernel/workqueue.c7
17 files changed, 429 insertions, 203 deletions
diff --git a/kernel/exit.c b/kernel/exit.c
index 21aa7b3001f..676149a4ac5 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -914,6 +914,15 @@ NORET_TYPE void do_exit(long code)
if (unlikely(!tsk->pid))
panic("Attempted to kill the idle task!");
+ /*
+ * If do_exit is called because this processes oopsed, it's possible
+ * that get_fs() was left as KERNEL_DS, so reset it to USER_DS before
+ * continuing. Amongst other possible reasons, this is to prevent
+ * mm_release()->clear_child_tid() from writing to a user-controlled
+ * kernel address.
+ */
+ set_fs(USER_DS);
+
tracehook_report_exit(&code);
validate_creds_for_do_exit(tsk);
diff --git a/kernel/fork.c b/kernel/fork.c
index 3b159c5991b..5447dc7defa 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -273,6 +273,7 @@ static struct task_struct *dup_task_struct(struct task_struct *orig)
setup_thread_stack(tsk, orig);
clear_user_return_notifier(tsk);
+ clear_tsk_need_resched(tsk);
stackend = end_of_stack(tsk);
*stackend = STACK_END_MAGIC; /* for overflow detection */
diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c
index 01b1d3a8898..6c8a2a9f8a7 100644
--- a/kernel/irq/proc.c
+++ b/kernel/irq/proc.c
@@ -214,7 +214,7 @@ static int irq_spurious_proc_show(struct seq_file *m, void *v)
static int irq_spurious_proc_open(struct inode *inode, struct file *file)
{
- return single_open(file, irq_spurious_proc_show, NULL);
+ return single_open(file, irq_spurious_proc_show, PDE(inode)->data);
}
static const struct file_operations irq_spurious_proc_fops = {
diff --git a/kernel/kthread.c b/kernel/kthread.c
index 2dc3786349d..ca61bbdd44b 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -265,6 +265,17 @@ int kthreadd(void *unused)
return 0;
}
+void __init_kthread_worker(struct kthread_worker *worker,
+ const char *name,
+ struct lock_class_key *key)
+{
+ spin_lock_init(&worker->lock);
+ lockdep_set_class_and_name(&worker->lock, key, name);
+ INIT_LIST_HEAD(&worker->work_list);
+ worker->task = NULL;
+}
+EXPORT_SYMBOL_GPL(__init_kthread_worker);
+
/**
* kthread_worker_fn - kthread function to process kthread_worker
* @worker_ptr: pointer to initialized kthread_worker
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index eac7e336433..2870feee81d 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -3824,6 +3824,8 @@ static void perf_event_task_event(struct perf_task_event *task_event)
rcu_read_lock();
list_for_each_entry_rcu(pmu, &pmus, entry) {
cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
+ if (cpuctx->active_pmu != pmu)
+ goto next;
perf_event_task_ctx(&cpuctx->ctx, task_event);
ctx = task_event->task_ctx;
@@ -3959,6 +3961,8 @@ static void perf_event_comm_event(struct perf_comm_event *comm_event)
rcu_read_lock();
list_for_each_entry_rcu(pmu, &pmus, entry) {
cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
+ if (cpuctx->active_pmu != pmu)
+ goto next;
perf_event_comm_ctx(&cpuctx->ctx, comm_event);
ctxn = pmu->task_ctx_nr;
@@ -4144,6 +4148,8 @@ got_name:
rcu_read_lock();
list_for_each_entry_rcu(pmu, &pmus, entry) {
cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
+ if (cpuctx->active_pmu != pmu)
+ goto next;
perf_event_mmap_ctx(&cpuctx->ctx, mmap_event,
vma->vm_flags & VM_EXEC);
@@ -4713,7 +4719,7 @@ static int perf_swevent_init(struct perf_event *event)
break;
}
- if (event_id > PERF_COUNT_SW_MAX)
+ if (event_id >= PERF_COUNT_SW_MAX)
return -ENOENT;
if (!event->parent) {
@@ -5145,20 +5151,36 @@ static void *find_pmu_context(int ctxn)
return NULL;
}
-static void free_pmu_context(void * __percpu cpu_context)
+static void update_pmu_context(struct pmu *pmu, struct pmu *old_pmu)
{
- struct pmu *pmu;
+ int cpu;
+
+ for_each_possible_cpu(cpu) {
+ struct perf_cpu_context *cpuctx;
+
+ cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu);
+
+ if (cpuctx->active_pmu == old_pmu)
+ cpuctx->active_pmu = pmu;
+ }
+}
+
+static void free_pmu_context(struct pmu *pmu)
+{
+ struct pmu *i;
mutex_lock(&pmus_lock);
/*
* Like a real lame refcount.
*/
- list_for_each_entry(pmu, &pmus, entry) {
- if (pmu->pmu_cpu_context == cpu_context)
+ list_for_each_entry(i, &pmus, entry) {
+ if (i->pmu_cpu_context == pmu->pmu_cpu_context) {
+ update_pmu_context(i, pmu);
goto out;
+ }
}
- free_percpu(cpu_context);
+ free_percpu(pmu->pmu_cpu_context);
out:
mutex_unlock(&pmus_lock);
}
@@ -5190,6 +5212,7 @@ int perf_pmu_register(struct pmu *pmu)
cpuctx->ctx.pmu = pmu;
cpuctx->jiffies_interval = 1;
INIT_LIST_HEAD(&cpuctx->rotation_list);
+ cpuctx->active_pmu = pmu;
}
got_cpu_context:
@@ -5241,7 +5264,7 @@ void perf_pmu_unregister(struct pmu *pmu)
synchronize_rcu();
free_percpu(pmu->pmu_disable_count);
- free_pmu_context(pmu->pmu_cpu_context);
+ free_pmu_context(pmu);
}
struct pmu *perf_init_event(struct perf_event *event)
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 657272e91d0..048d0b51483 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -327,7 +327,6 @@ static int create_image(int platform_mode)
int hibernation_snapshot(int platform_mode)
{
int error;
- gfp_t saved_mask;
error = platform_begin(platform_mode);
if (error)
@@ -339,7 +338,7 @@ int hibernation_snapshot(int platform_mode)
goto Close;
suspend_console();
- saved_mask = clear_gfp_allowed_mask(GFP_IOFS);
+ pm_restrict_gfp_mask();
error = dpm_suspend_start(PMSG_FREEZE);
if (error)
goto Recover_platform;
@@ -348,7 +347,10 @@ int hibernation_snapshot(int platform_mode)
goto Recover_platform;
error = create_image(platform_mode);
- /* Control returns here after successful restore */
+ /*
+ * Control returns here (1) after the image has been created or the
+ * image creation has failed and (2) after a successful restore.
+ */
Resume_devices:
/* We may need to release the preallocated image pages here. */
@@ -357,7 +359,10 @@ int hibernation_snapshot(int platform_mode)
dpm_resume_end(in_suspend ?
(error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
- set_gfp_allowed_mask(saved_mask);
+
+ if (error || !in_suspend)
+ pm_restore_gfp_mask();
+
resume_console();
Close:
platform_end(platform_mode);
@@ -452,17 +457,16 @@ static int resume_target_kernel(bool platform_mode)
int hibernation_restore(int platform_mode)
{
int error;
- gfp_t saved_mask;
pm_prepare_console();
suspend_console();
- saved_mask = clear_gfp_allowed_mask(GFP_IOFS);
+ pm_restrict_gfp_mask();
error = dpm_suspend_start(PMSG_QUIESCE);
if (!error) {
error = resume_target_kernel(platform_mode);
dpm_resume_end(PMSG_RECOVER);
}
- set_gfp_allowed_mask(saved_mask);
+ pm_restore_gfp_mask();
resume_console();
pm_restore_console();
return error;
@@ -476,7 +480,6 @@ int hibernation_restore(int platform_mode)
int hibernation_platform_enter(void)
{
int error;
- gfp_t saved_mask;
if (!hibernation_ops)
return -ENOSYS;
@@ -492,7 +495,6 @@ int hibernation_platform_enter(void)
entering_platform_hibernation = true;
suspend_console();
- saved_mask = clear_gfp_allowed_mask(GFP_IOFS);
error = dpm_suspend_start(PMSG_HIBERNATE);
if (error) {
if (hibernation_ops->recover)
@@ -536,7 +538,6 @@ int hibernation_platform_enter(void)
Resume_devices:
entering_platform_hibernation = false;
dpm_resume_end(PMSG_RESTORE);
- set_gfp_allowed_mask(saved_mask);
resume_console();
Close:
@@ -646,6 +647,7 @@ int hibernate(void)
swsusp_free();
if (!error)
power_down();
+ pm_restore_gfp_mask();
} else {
pr_debug("PM: Image restored successfully.\n");
}
diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index 7335952ee47..ecf770509d0 100644
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -197,7 +197,6 @@ static int suspend_enter(suspend_state_t state)
int suspend_devices_and_enter(suspend_state_t state)
{
int error;
- gfp_t saved_mask;
if (!suspend_ops)
return -ENOSYS;
@@ -208,7 +207,7 @@ int suspend_devices_and_enter(suspend_state_t state)
goto Close;
}
suspend_console();
- saved_mask = clear_gfp_allowed_mask(GFP_IOFS);
+ pm_restrict_gfp_mask();
suspend_test_start();
error = dpm_suspend_start(PMSG_SUSPEND);
if (error) {
@@ -225,7 +224,7 @@ int suspend_devices_and_enter(suspend_state_t state)
suspend_test_start();
dpm_resume_end(PMSG_RESUME);
suspend_test_finish("resume devices");
- set_gfp_allowed_mask(saved_mask);
+ pm_restore_gfp_mask();
resume_console();
Close:
if (suspend_ops->end)
diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index a0e4a86ccf9..8c7e4832b9b 100644
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -6,6 +6,7 @@
*
* Copyright (C) 1998,2001-2005 Pavel Machek <pavel@ucw.cz>
* Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl>
+ * Copyright (C) 2010 Bojan Smojver <bojan@rexursive.com>
*
* This file is released under the GPLv2.
*
@@ -29,7 +30,7 @@
#include "power.h"
-#define HIBERNATE_SIG "LINHIB0001"
+#define HIBERNATE_SIG "S1SUSPEND"
/*
* The swap map is a data structure used for keeping track of each page
@@ -753,30 +754,43 @@ static int load_image_lzo(struct swap_map_handle *handle,
{
unsigned int m;
int error = 0;
+ struct bio *bio;
struct timeval start;
struct timeval stop;
unsigned nr_pages;
- size_t off, unc_len, cmp_len;
- unsigned char *unc, *cmp, *page;
+ size_t i, off, unc_len, cmp_len;
+ unsigned char *unc, *cmp, *page[LZO_CMP_PAGES];
- page = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH);
- if (!page) {
- printk(KERN_ERR "PM: Failed to allocate LZO page\n");
- return -ENOMEM;
+ for (i = 0; i < LZO_CMP_PAGES; i++) {
+ page[i] = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH);
+ if (!page[i]) {
+ printk(KERN_ERR "PM: Failed to allocate LZO page\n");
+
+ while (i)
+ free_page((unsigned long)page[--i]);
+
+ return -ENOMEM;
+ }
}
unc = vmalloc(LZO_UNC_SIZE);
if (!unc) {
printk(KERN_ERR "PM: Failed to allocate LZO uncompressed\n");
- free_page((unsigned long)page);
+
+ for (i = 0; i < LZO_CMP_PAGES; i++)
+ free_page((unsigned long)page[i]);
+
return -ENOMEM;
}
cmp = vmalloc(LZO_CMP_SIZE);
if (!cmp) {
printk(KERN_ERR "PM: Failed to allocate LZO compressed\n");
+
vfree(unc);
- free_page((unsigned long)page);
+ for (i = 0; i < LZO_CMP_PAGES; i++)
+ free_page((unsigned long)page[i]);
+
return -ENOMEM;
}
@@ -787,6 +801,7 @@ static int load_image_lzo(struct swap_map_handle *handle,
if (!m)
m = 1;
nr_pages = 0;
+ bio = NULL;
do_gettimeofday(&start);
error = snapshot_write_next(snapshot);
@@ -794,11 +809,11 @@ static int load_image_lzo(struct swap_map_handle *handle,
goto out_finish;
for (;;) {
- error = swap_read_page(handle, page, NULL); /* sync */
+ error = swap_read_page(handle, page[0], NULL); /* sync */
if (error)
break;
- cmp_len = *(size_t *)page;
+ cmp_len = *(size_t *)page[0];
if (unlikely(!cmp_len ||
cmp_len > lzo1x_worst_compress(LZO_UNC_SIZE))) {
printk(KERN_ERR "PM: Invalid LZO compressed length\n");
@@ -806,13 +821,20 @@ static int load_image_lzo(struct swap_map_handle *handle,
break;
}
- memcpy(cmp, page, PAGE_SIZE);
- for (off = PAGE_SIZE; off < LZO_HEADER + cmp_len; off += PAGE_SIZE) {
- error = swap_read_page(handle, page, NULL); /* sync */
+ for (off = PAGE_SIZE, i = 1;
+ off < LZO_HEADER + cmp_len; off += PAGE_SIZE, i++) {
+ error = swap_read_page(handle, page[i], &bio);
if (error)
goto out_finish;
+ }
- memcpy(cmp + off, page, PAGE_SIZE);
+ error = hib_wait_on_bio_chain(&bio); /* need all data now */
+ if (error)
+ goto out_finish;
+
+ for (off = 0, i = 0;
+ off < LZO_HEADER + cmp_len; off += PAGE_SIZE, i++) {
+ memcpy(cmp + off, page[i], PAGE_SIZE);
}
unc_len = LZO_UNC_SIZE;
@@ -857,7 +879,8 @@ out_finish:
vfree(cmp);
vfree(unc);
- free_page((unsigned long)page);
+ for (i = 0; i < LZO_CMP_PAGES; i++)
+ free_page((unsigned long)page[i]);
return error;
}
diff --git a/kernel/power/user.c b/kernel/power/user.c
index e819e17877c..c36c3b9e8a8 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -137,7 +137,7 @@ static int snapshot_release(struct inode *inode, struct file *filp)
free_all_swap_pages(data->swap);
if (data->frozen)
thaw_processes();
- pm_notifier_call_chain(data->mode == O_WRONLY ?
+ pm_notifier_call_chain(data->mode == O_RDONLY ?
PM_POST_HIBERNATION : PM_POST_RESTORE);
atomic_inc(&snapshot_device_available);
@@ -263,6 +263,7 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
case SNAPSHOT_UNFREEZE:
if (!data->frozen || data->ready)
break;
+ pm_restore_gfp_mask();
thaw_processes();
usermodehelper_enable();
data->frozen = 0;
@@ -275,6 +276,7 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
error = -EPERM;
break;
}
+ pm_restore_gfp_mask();
error = hibernation_snapshot(data->platform_support);
if (!error)
error = put_user(in_suspend, (int __user *)arg);
diff --git a/kernel/printk.c b/kernel/printk.c
index 9a2264fc42c..a23315dc449 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -1082,13 +1082,15 @@ void printk_tick(void)
int printk_needs_cpu(int cpu)
{
+ if (unlikely(cpu_is_offline(cpu)))
+ printk_tick();
return per_cpu(printk_pending, cpu);
}
void wake_up_klogd(void)
{
if (waitqueue_active(&log_wait))
- __raw_get_cpu_var(printk_pending) = 1;
+ this_cpu_write(printk_pending, 1);
}
/**
diff --git a/kernel/resource.c b/kernel/resource.c
index 9fad33efd0d..798e2fae2a0 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -40,23 +40,6 @@ EXPORT_SYMBOL(iomem_resource);
static DEFINE_RWLOCK(resource_lock);
-/*
- * By default, we allocate free space bottom-up. The architecture can request
- * top-down by clearing this flag. The user can override the architecture's
- * choice with the "resource_alloc_from_bottom" kernel boot option, but that
- * should only be a debugging tool.
- */
-int resource_alloc_from_bottom = 1;
-
-static __init int setup_alloc_from_bottom(char *s)
-{
- printk(KERN_INFO
- "resource: allocating from bottom-up; please report a bug\n");
- resource_alloc_from_bottom = 1;
- return 0;
-}
-early_param("resource_alloc_from_bottom", setup_alloc_from_bottom);
-
static void *r_next(struct seq_file *m, void *v, loff_t *pos)
{
struct resource *p = v;
@@ -374,6 +357,10 @@ int __weak page_is_ram(unsigned long pfn)
return walk_system_ram_range(pfn, 1, NULL, __is_ram) == 1;
}
+void __weak arch_remove_reservations(struct resource *avail)
+{
+}
+
static resource_size_t simple_align_resource(void *data,
const struct resource *avail,
resource_size_t size,
@@ -397,74 +384,7 @@ static bool resource_contains(struct resource *res1, struct resource *res2)
}
/*
- * Find the resource before "child" in the sibling list of "root" children.
- */
-static struct resource *find_sibling_prev(struct resource *root, struct resource *child)
-{
- struct resource *this;
-
- for (this = root->child; this; this = this->sibling)
- if (this->sibling == child)
- return this;
-
- return NULL;
-}
-
-/*
* Find empty slot in the resource tree given range and alignment.
- * This version allocates from the end of the root resource first.
- */
-static int find_resource_from_top(struct resource *root, struct resource *new,
- resource_size_t size, resource_size_t min,
- resource_size_t max, resource_size_t align,
- resource_size_t (*alignf)(void *,
- const struct resource *,
- resource_size_t,
- resource_size_t),
- void *alignf_data)
-{
- struct resource *this;
- struct resource tmp, avail, alloc;
-
- tmp.start = root->end;
- tmp.end = root->end;
-
- this = find_sibling_prev(root, NULL);
- for (;;) {
- if (this) {
- if (this->end < root->end)
- tmp.start = this->end + 1;
- } else
- tmp.start = root->start;
-
- resource_clip(&tmp, min, max);
-
- /* Check for overflow after ALIGN() */
- avail = *new;
- avail.start = ALIGN(tmp.start, align);
- avail.end = tmp.end;
- if (avail.start >= tmp.start) {
- alloc.start = alignf(alignf_data, &avail, size, align);
- alloc.end = alloc.start + size - 1;
- if (resource_contains(&avail, &alloc)) {
- new->start = alloc.start;
- new->end = alloc.end;
- return 0;
- }
- }
-
- if (!this || this->start == root->start)
- break;
-
- tmp.end = this->start - 1;
- this = find_sibling_prev(root, this);
- }
- return -EBUSY;
-}
-
-/*
- * Find empty slot in the resource tree given range and alignment.
- * This version allocates from the beginning of the root resource first.
*/
static int find_resource(struct resource *root, struct resource *new,
resource_size_t size, resource_size_t min,
@@ -478,23 +398,24 @@ static int find_resource(struct resource *root, struct resource *new,
struct resource *this = root->child;
struct resource tmp = *new, avail, alloc;
+ tmp.flags = new->flags;
tmp.start = root->start;
/*
- * Skip past an allocated resource that starts at 0, since the
- * assignment of this->start - 1 to tmp->end below would cause an
- * underflow.
+ * Skip past an allocated resource that starts at 0, since the assignment
+ * of this->start - 1 to tmp->end below would cause an underflow.
*/
if (this && this->start == 0) {
tmp.start = this->end + 1;
this = this->sibling;
}
- for (;;) {
+ for(;;) {
if (this)
tmp.end = this->start - 1;
else
tmp.end = root->end;
resource_clip(&tmp, min, max);
+ arch_remove_reservations(&tmp);
/* Check for overflow after ALIGN() */
avail = *new;
@@ -509,10 +430,8 @@ static int find_resource(struct resource *root, struct resource *new,
return 0;
}
}
-
if (!this)
break;
-
tmp.start = this->end + 1;
this = this->sibling;
}
@@ -545,10 +464,7 @@ int allocate_resource(struct resource *root, struct resource *new,
alignf = simple_align_resource;
write_lock(&resource_lock);
- if (resource_alloc_from_bottom)
- err = find_resource(root, new, size, min, max, align, alignf, alignf_data);
- else
- err = find_resource_from_top(root, new, size, min, max, align, alignf, alignf_data);
+ err = find_resource(root, new, size, min, max, align, alignf, alignf_data);
if (err >= 0 && __request_resource(root, new))
err = -EBUSY;
write_unlock(&resource_lock);
diff --git a/kernel/sched.c b/kernel/sched.c
index dc91a4d09ac..297d1a0eedb 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -636,22 +636,18 @@ static inline struct task_group *task_group(struct task_struct *p)
#endif /* CONFIG_CGROUP_SCHED */
-static u64 irq_time_cpu(int cpu);
-static void sched_irq_time_avg_update(struct rq *rq, u64 irq_time);
+static void update_rq_clock_task(struct rq *rq, s64 delta);
-inline void update_rq_clock(struct rq *rq)
+static void update_rq_clock(struct rq *rq)
{
- if (!rq->skip_clock_update) {
- int cpu = cpu_of(rq);
- u64 irq_time;
+ s64 delta;
- rq->clock = sched_clock_cpu(cpu);
- irq_time = irq_time_cpu(cpu);
- if (rq->clock - irq_time > rq->clock_task)
- rq->clock_task = rq->clock - irq_time;
+ if (rq->skip_clock_update)
+ return;
- sched_irq_time_avg_update(rq, irq_time);
- }
+ delta = sched_clock_cpu(cpu_of(rq)) - rq->clock;
+ rq->clock += delta;
+ update_rq_clock_task(rq, delta);
}
/*
@@ -1924,10 +1920,9 @@ static void deactivate_task(struct rq *rq, struct task_struct *p, int flags)
* They are read and saved off onto struct rq in update_rq_clock().
* This may result in other CPU reading this CPU's irq time and can
* race with irq/account_system_vtime on this CPU. We would either get old
- * or new value (or semi updated value on 32 bit) with a side effect of
- * accounting a slice of irq time to wrong task when irq is in progress
- * while we read rq->clock. That is a worthy compromise in place of having
- * locks on each irq in account_system_time.
+ * or new value with a side effect of accounting a slice of irq time to wrong
+ * task when irq is in progress while we read rq->clock. That is a worthy
+ * compromise in place of having locks on each irq in account_system_time.
*/
static DEFINE_PER_CPU(u64, cpu_hardirq_time);
static DEFINE_PER_CPU(u64, cpu_softirq_time);
@@ -1945,19 +1940,58 @@ void disable_sched_clock_irqtime(void)
sched_clock_irqtime = 0;
}
-static u64 irq_time_cpu(int cpu)
+#ifndef CONFIG_64BIT
+static DEFINE_PER_CPU(seqcount_t, irq_time_seq);
+
+static inline void irq_time_write_begin(void)
{
- if (!sched_clock_irqtime)
- return 0;
+ __this_cpu_inc(irq_time_seq.sequence);
+ smp_wmb();
+}
+
+static inline void irq_time_write_end(void)
+{
+ smp_wmb();
+ __this_cpu_inc(irq_time_seq.sequence);
+}
+
+static inline u64 irq_time_read(int cpu)
+{
+ u64 irq_time;
+ unsigned seq;
+ do {
+ seq = read_seqcount_begin(&per_cpu(irq_time_seq, cpu));
+ irq_time = per_cpu(cpu_softirq_time, cpu) +
+ per_cpu(cpu_hardirq_time, cpu);
+ } while (read_seqcount_retry(&per_cpu(irq_time_seq, cpu), seq));
+
+ return irq_time;
+}
+#else /* CONFIG_64BIT */
+static inline void irq_time_write_begin(void)
+{
+}
+
+static inline void irq_time_write_end(void)
+{
+}
+
+static inline u64 irq_time_read(int cpu)
+{
return per_cpu(cpu_softirq_time, cpu) + per_cpu(cpu_hardirq_time, cpu);
}
+#endif /* CONFIG_64BIT */
+/*
+ * Called before incrementing preempt_count on {soft,}irq_enter
+ * and before decrementing preempt_count on {soft,}irq_exit.
+ */
void account_system_vtime(struct task_struct *curr)
{
unsigned long flags;
+ s64 delta;
int cpu;
- u64 now, delta;
if (!sched_clock_irqtime)
return;
@@ -1965,9 +1999,10 @@ void account_system_vtime(struct task_struct *curr)
local_irq_save(flags);
cpu = smp_processor_id();
- now = sched_clock_cpu(cpu);
- delta = now - per_cpu(irq_start_time, cpu);
- per_cpu(irq_start_time, cpu) = now;
+ delta = sched_clock_cpu(cpu) - __this_cpu_read(irq_start_time);
+ __this_cpu_add(irq_start_time, delta);
+
+ irq_time_write_begin();
/*
* We do not account for softirq time from ksoftirqd here.
* We want to continue accounting softirq time to ksoftirqd thread
@@ -1975,33 +2010,55 @@ void account_system_vtime(struct task_struct *curr)
* that do not consume any time, but still wants to run.
*/
if (hardirq_count())
- per_cpu(cpu_hardirq_time, cpu) += delta;
+ __this_cpu_add(cpu_hardirq_time, delta);
else if (in_serving_softirq() && !(curr->flags & PF_KSOFTIRQD))
- per_cpu(cpu_softirq_time, cpu) += delta;
+ __this_cpu_add(cpu_softirq_time, delta);
+ irq_time_write_end();
local_irq_restore(flags);
}
EXPORT_SYMBOL_GPL(account_system_vtime);
-static void sched_irq_time_avg_update(struct rq *rq, u64 curr_irq_time)
+static void update_rq_clock_task(struct rq *rq, s64 delta)
{
- if (sched_clock_irqtime && sched_feat(NONIRQ_POWER)) {
- u64 delta_irq = curr_irq_time - rq->prev_irq_time;
- rq->prev_irq_time = curr_irq_time;
- sched_rt_avg_update(rq, delta_irq);
- }
+ s64 irq_delta;
+
+ irq_delta = irq_time_read(cpu_of(rq)) - rq->prev_irq_time;
+
+ /*
+ * Since irq_time is only updated on {soft,}irq_exit, we might run into
+ * this case when a previous update_rq_clock() happened inside a
+ * {soft,}irq region.
+ *
+ * When this happens, we stop ->clock_task and only update the
+ * prev_irq_time stamp to account for the part that fit, so that a next
+ * update will consume the rest. This ensures ->clock_task is
+ * monotonic.
+ *
+ * It does however cause some slight miss-attribution of {soft,}irq
+ * time, a more accurate solution would be to update the irq_time using
+ * the current rq->clock timestamp, except that would require using
+ * atomic ops.
+ */
+ if (irq_delta > delta)
+ irq_delta = delta;
+
+ rq->prev_irq_time += irq_delta;
+ delta -= irq_delta;
+ rq->clock_task += delta;
+
+ if (irq_delta && sched_feat(NONIRQ_POWER))
+ sched_rt_avg_update(rq, irq_delta);
}
-#else
+#else /* CONFIG_IRQ_TIME_ACCOUNTING */
-static u64 irq_time_cpu(int cpu)
+static void update_rq_clock_task(struct rq *rq, s64 delta)
{
- return 0;
+ rq->clock_task += delta;
}
-static void sched_irq_time_avg_update(struct rq *rq, u64 curr_irq_time) { }
-
-#endif
+#endif /* CONFIG_IRQ_TIME_ACCOUNTING */
#include "sched_idletask.c"
#include "sched_fair.c"
@@ -2129,7 +2186,7 @@ static void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags)
* A queue event has occurred, and we're going to schedule. In
* this case, we can save a useless back to back clock update.
*/
- if (test_tsk_need_resched(rq->curr))
+ if (rq->curr->se.on_rq && test_tsk_need_resched(rq->curr))
rq->skip_clock_update = 1;
}
@@ -3119,6 +3176,15 @@ static long calc_load_fold_active(struct rq *this_rq)
return delta;
}
+static unsigned long
+calc_load(unsigned long load, unsigned long exp, unsigned long active)
+{
+ load *= exp;
+ load += active * (FIXED_1 - exp);
+ load += 1UL << (FSHIFT - 1);
+ return load >> FSHIFT;
+}
+
#ifdef CONFIG_NO_HZ
/*
* For NO_HZ we delay the active fold to the next LOAD_FREQ update.
@@ -3148,6 +3214,128 @@ static long calc_load_fold_idle(void)
return delta;
}
+
+/**
+ * fixed_power_int - compute: x^n, in O(log n) time
+ *
+ * @x: base of the power
+ * @frac_bits: fractional bits of @x
+ * @n: power to raise @x to.
+ *
+ * By exploiting the relation between the definition of the natural power
+ * function: x^n := x*x*...*x (x multiplied by itself for n times), and
+ * the binary encoding of numbers used by computers: n := \Sum n_i * 2^i,
+ * (where: n_i \elem {0, 1}, the binary vector representing n),
+ * we find: x^n := x^(\Sum n_i * 2^i) := \Prod x^(n_i * 2^i), which is
+ * of course trivially computable in O(log_2 n), the length of our binary
+ * vector.
+ */
+static unsigned long
+fixed_power_int(unsigned long x, unsigned int frac_bits, unsigned int n)
+{
+ unsigned long result = 1UL << frac_bits;
+
+ if (n) for (;;) {
+ if (n & 1) {
+ result *= x;
+ result += 1UL << (frac_bits - 1);
+ result >>= frac_bits;
+ }
+ n >>= 1;
+ if (!n)
+ break;
+ x *= x;
+ x += 1UL << (frac_bits - 1);
+ x >>= frac_bits;
+ }
+
+ return result;
+}
+
+/*
+ * a1 = a0 * e + a * (1 - e)
+ *
+ * a2 = a1 * e + a * (1 - e)
+ * = (a0 * e + a * (1 - e)) * e + a * (1 - e)
+ * = a0 * e^2 + a * (1 - e) * (1 + e)
+ *
+ * a3 = a2 * e + a * (1 - e)
+ * = (a0 * e^2 + a * (1 - e) * (1 + e)) * e + a * (1 - e)
+ * = a0 * e^3 + a * (1 - e) * (1 + e + e^2)
+ *
+ * ...
+ *
+ * an = a0 * e^n + a * (1 - e) * (1 + e + ... + e^n-1) [1]
+ * = a0 * e^n + a * (1 - e) * (1 - e^n)/(1 - e)
+ * = a0 * e^n + a * (1 - e^n)
+ *
+ * [1] application of the geometric series:
+ *
+ * n 1 - x^(n+1)
+ * S_n := \Sum x^i = -------------
+ * i=0 1 - x
+ */
+static unsigned long
+calc_load_n(unsigned long load, unsigned long exp,
+ unsigned long active, unsigned int n)
+{
+
+ return calc_load(load, fixed_power_int(exp, FSHIFT, n), active);
+}
+
+/*
+ * NO_HZ can leave us missing all per-cpu ticks calling
+ * calc_load_account_active(), but since an idle CPU folds its delta into
+ * calc_load_tasks_idle per calc_load_account_idle(), all we need to do is fold
+ * in the pending idle delta if our idle period crossed a load cycle boundary.
+ *
+ * Once we've updated the global active value, we need to apply the exponential
+ * weights adjusted to the number of cycles missed.
+ */
+static void calc_global_nohz(unsigned long ticks)
+{
+ long delta, active, n;
+
+ if (time_before(jiffies, calc_load_update))
+ return;
+
+ /*
+ * If we crossed a calc_load_update boundary, make sure to fold
+ * any pending idle changes, the respective CPUs might have
+ * missed the tick driven calc_load_account_active() update
+ * due to NO_HZ.
+ */
+ delta = calc_load_fold_idle();
+ if (delta)
+ atomic_long_add(delta, &calc_load_tasks);
+
+ /*
+ * If we were idle for multiple load cycles, apply them.
+ */
+ if (ticks >= LOAD_FREQ) {
+ n = ticks / LOAD_FREQ;
+
+ active = atomic_long_read(&calc_load_tasks);
+ active = active > 0 ? active * FIXED_1 : 0;
+
+ avenrun[0] = calc_load_n(avenrun[0], EXP_1, active, n);
+ avenrun[1] = calc_load_n(avenrun[1], EXP_5, active, n);
+ avenrun[2] = calc_load_n(avenrun[2], EXP_15, active, n);
+
+ calc_load_update += n * LOAD_FREQ;
+ }
+
+ /*
+ * Its possible the remainder of the above division also crosses
+ * a LOAD_FREQ period, the regular check in calc_global_load()
+ * which comes after this will take care of that.
+ *
+ * Consider us being 11 ticks before a cycle completion, and us
+ * sleeping for 4*LOAD_FREQ + 22 ticks, then the above code will
+ * age us 4 cycles, and the test in calc_global_load() will
+ * pick up the final one.
+ */
+}
#else
static void calc_load_account_idle(struct rq *this_rq)
{
@@ -3157,6 +3345,10 @@ static inline long calc_load_fold_idle(void)
{
return 0;
}
+
+static void calc_global_nohz(unsigned long ticks)
+{
+}
#endif
/**
@@ -3174,24 +3366,17 @@ void get_avenrun(unsigned long *loads, unsigned long offset, int shift)
loads[2] = (avenrun[2] + offset) << shift;
}
-static unsigned long
-calc_load(unsigned long load, unsigned long exp, unsigned long active)
-{
- load *= exp;
- load += active * (FIXED_1 - exp);
- return load >> FSHIFT;
-}
-
/*
* calc_load - update the avenrun load estimates 10 ticks after the
* CPUs have updated calc_load_tasks.
*/
-void calc_global_load(void)
+void calc_global_load(unsigned long ticks)
{
- unsigned long upd = calc_load_update + 10;
long active;
- if (time_before(jiffies, upd))
+ calc_global_nohz(ticks);
+
+ if (time_before(jiffies, calc_load_update + 10))
return;
active = atomic_long_read(&calc_load_tasks);
@@ -3845,7 +4030,6 @@ static void put_prev_task(struct rq *rq, struct task_struct *prev)
{
if (prev->se.on_rq)
update_rq_clock(rq);
- rq->skip_clock_update = 0;
prev->sched_class->put_prev_task(rq, prev);
}
@@ -3903,7 +4087,6 @@ need_resched_nonpreemptible:
hrtick_clear(rq);
raw_spin_lock_irq(&rq->lock);
- clear_tsk_need_resched(prev);
switch_count = &prev->nivcsw;
if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) {
@@ -3935,6 +4118,8 @@ need_resched_nonpreemptible:
put_prev_task(rq, prev);
next = pick_next_task(rq);
+ clear_tsk_need_resched(prev);
+ rq->skip_clock_update = 0;
if (likely(prev != next)) {
sched_info_switch(prev, next);
diff --git a/kernel/taskstats.c b/kernel/taskstats.c
index c8231fb1570..3308fd7f1b5 100644
--- a/kernel/taskstats.c
+++ b/kernel/taskstats.c
@@ -349,25 +349,47 @@ static int parse(struct nlattr *na, struct cpumask *mask)
return ret;
}
+#ifdef CONFIG_IA64
+#define TASKSTATS_NEEDS_PADDING 1
+#endif
+
static struct taskstats *mk_reply(struct sk_buff *skb, int type, u32 pid)
{
struct nlattr *na, *ret;
int aggr;
- /* If we don't pad, we end up with alignment on a 4 byte boundary.
- * This causes lots of runtime warnings on systems requiring 8 byte
- * alignment */
- u32 pids[2] = { pid, 0 };
- int pid_size = ALIGN(sizeof(pid), sizeof(long));
-
aggr = (type == TASKSTATS_TYPE_PID)
? TASKSTATS_TYPE_AGGR_PID
: TASKSTATS_TYPE_AGGR_TGID;
+ /*
+ * The taskstats structure is internally aligned on 8 byte
+ * boundaries but the layout of the aggregrate reply, with
+ * two NLA headers and the pid (each 4 bytes), actually
+ * force the entire structure to be unaligned. This causes
+ * the kernel to issue unaligned access warnings on some
+ * architectures like ia64. Unfortunately, some software out there
+ * doesn't properly unroll the NLA packet and assumes that the start
+ * of the taskstats structure will always be 20 bytes from the start
+ * of the netlink payload. Aligning the start of the taskstats
+ * structure breaks this software, which we don't want. So, for now
+ * the alignment only happens on architectures that require it
+ * and those users will have to update to fixed versions of those
+ * packages. Space is reserved in the packet only when needed.
+ * This ifdef should be removed in several years e.g. 2012 once
+ * we can be confident that fixed versions are installed on most
+ * systems. We add the padding before the aggregate since the
+ * aggregate is already a defined type.
+ */
+#ifdef TASKSTATS_NEEDS_PADDING
+ if (nla_put(skb, TASKSTATS_TYPE_NULL, 0, NULL) < 0)
+ goto err;
+#endif
na = nla_nest_start(skb, aggr);
if (!na)
goto err;
- if (nla_put(skb, type, pid_size, pids) < 0)
+
+ if (nla_put(skb, type, sizeof(pid), &pid) < 0)
goto err;
ret = nla_reserve(skb, TASKSTATS_TYPE_STATS, sizeof(struct taskstats));
if (!ret)
@@ -456,6 +478,18 @@ out:
return rc;
}
+static size_t taskstats_packet_size(void)
+{
+ size_t size;
+
+ size = nla_total_size(sizeof(u32)) +
+ nla_total_size(sizeof(struct taskstats)) + nla_total_size(0);
+#ifdef TASKSTATS_NEEDS_PADDING
+ size += nla_total_size(0); /* Padding for alignment */
+#endif
+ return size;
+}
+
static int cmd_attr_pid(struct genl_info *info)
{
struct taskstats *stats;
@@ -464,8 +498,7 @@ static int cmd_attr_pid(struct genl_info *info)
u32 pid;
int rc;
- size = nla_total_size(sizeof(u32)) +
- nla_total_size(sizeof(struct taskstats)) + nla_total_size(0);
+ size = taskstats_packet_size();
rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size);
if (rc < 0)
@@ -494,8 +527,7 @@ static int cmd_attr_tgid(struct genl_info *info)
u32 tgid;
int rc;
- size = nla_total_size(sizeof(u32)) +
- nla_total_size(sizeof(struct taskstats)) + nla_total_size(0);
+ size = taskstats_packet_size();
rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size);
if (rc < 0)
@@ -570,8 +602,7 @@ void taskstats_exit(struct task_struct *tsk, int group_dead)
/*
* Size includes space for nested attributes
*/
- size = nla_total_size(sizeof(u32)) +
- nla_total_size(sizeof(struct taskstats)) + nla_total_size(0);
+ size = taskstats_packet_size();
is_thread_group = !!taskstats_tgid_alloc(tsk);
if (is_thread_group) {
diff --git a/kernel/timer.c b/kernel/timer.c
index 68a9ae7679b..353b9227c2e 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -1252,6 +1252,12 @@ unsigned long get_next_timer_interrupt(unsigned long now)
struct tvec_base *base = __get_cpu_var(tvec_bases);
unsigned long expires;
+ /*
+ * Pretend that there is no timer pending if the cpu is offline.
+ * Possible pending timers will be migrated later to an active cpu.
+ */
+ if (cpu_is_offline(smp_processor_id()))
+ return now + NEXT_TIMER_MAX_DELTA;
spin_lock(&base->lock);
if (time_before_eq(base->next_timer, base->timer_jiffies))
base->next_timer = __next_timer_interrupt(base);
@@ -1319,7 +1325,7 @@ void do_timer(unsigned long ticks)
{
jiffies_64 += ticks;
update_wall_time();
- calc_global_load();
+ calc_global_load(ticks);
}
#ifdef __ARCH_WANT_SYS_ALARM
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 9ed509a015d..bd1c35a4fbc 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -3853,6 +3853,13 @@ int ring_buffer_read_page(struct ring_buffer *buffer,
/* Need to copy one event at a time */
do {
+ /* We need the size of one event, because
+ * rb_advance_reader only advances by one event,
+ * whereas rb_event_ts_length may include the size of
+ * one or two events.
+ * We have already ensured there's enough space if this
+ * is a time extend. */
+ size = rb_event_length(event);
memcpy(bpage->data + pos, rpage->data + rpos, size);
len -= size;
@@ -3867,7 +3874,7 @@ int ring_buffer_read_page(struct ring_buffer *buffer,
event = rb_reader_event(cpu_buffer);
/* Always keep the time extend and data together */
size = rb_event_ts_length(event);
- } while (len > size);
+ } while (len >= size);
/* update bpage */
local_set(&bpage->commit, pos);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index c380612273b..f8cf959bad4 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2338,11 +2338,19 @@ tracing_write_stub(struct file *filp, const char __user *ubuf,
return count;
}
+static loff_t tracing_seek(struct file *file, loff_t offset, int origin)
+{
+ if (file->f_mode & FMODE_READ)
+ return seq_lseek(file, offset, origin);
+ else
+ return 0;
+}
+
static const struct file_operations tracing_fops = {
.open = tracing_open,
.read = seq_read,
.write = tracing_write_stub,
- .llseek = seq_lseek,
+ .llseek = tracing_seek,
.release = tracing_release,
};
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 90db1bd1a97..e785b0f2aea 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -661,7 +661,7 @@ void wq_worker_waking_up(struct task_struct *task, unsigned int cpu)
{
struct worker *worker = kthread_data(task);
- if (likely(!(worker->flags & WORKER_NOT_RUNNING)))
+ if (!(worker->flags & WORKER_NOT_RUNNING))
atomic_inc(get_gcwq_nr_running(cpu));
}
@@ -687,7 +687,7 @@ struct task_struct *wq_worker_sleeping(struct task_struct *task,
struct global_cwq *gcwq = get_gcwq(cpu);
atomic_t *nr_running = get_gcwq_nr_running(cpu);
- if (unlikely(worker->flags & WORKER_NOT_RUNNING))
+ if (worker->flags & WORKER_NOT_RUNNING)
return NULL;
/* this can only happen on the local cpu */
@@ -3692,7 +3692,8 @@ static int __init init_workqueues(void)
system_nrt_wq = alloc_workqueue("events_nrt", WQ_NON_REENTRANT, 0);
system_unbound_wq = alloc_workqueue("events_unbound", WQ_UNBOUND,
WQ_UNBOUND_MAX_ACTIVE);
- BUG_ON(!system_wq || !system_long_wq || !system_nrt_wq);
+ BUG_ON(!system_wq || !system_long_wq || !system_nrt_wq ||
+ !system_unbound_wq);
return 0;
}
early_initcall(init_workqueues);
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-17 17:58:30 +0000