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Diffstat (limited to 'mm/oom_kill.c')
-rw-r--r--mm/oom_kill.c65
1 files changed, 37 insertions, 28 deletions
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index ddf74487f848..d4a929d79470 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -274,7 +274,7 @@ static enum oom_constraint constrained_alloc(struct oom_control *oc,
#endif
enum oom_scan_t oom_scan_process_thread(struct oom_control *oc,
- struct task_struct *task, unsigned long totalpages)
+ struct task_struct *task)
{
if (oom_unkillable_task(task, NULL, oc->nodemask))
return OOM_SCAN_CONTINUE;
@@ -311,7 +311,7 @@ static struct task_struct *select_bad_process(struct oom_control *oc,
for_each_process(p) {
unsigned int points;
- switch (oom_scan_process_thread(oc, p, totalpages)) {
+ switch (oom_scan_process_thread(oc, p)) {
case OOM_SCAN_SELECT:
chosen = p;
chosen_points = ULONG_MAX;
@@ -383,8 +383,7 @@ static void dump_tasks(struct mem_cgroup *memcg, const nodemask_t *nodemask)
rcu_read_unlock();
}
-static void dump_header(struct oom_control *oc, struct task_struct *p,
- struct mem_cgroup *memcg)
+static void dump_header(struct oom_control *oc, struct task_struct *p)
{
pr_warn("%s invoked oom-killer: gfp_mask=%#x(%pGg), order=%d, oom_score_adj=%hd\n",
current->comm, oc->gfp_mask, &oc->gfp_mask, oc->order,
@@ -392,12 +391,12 @@ static void dump_header(struct oom_control *oc, struct task_struct *p,
cpuset_print_current_mems_allowed();
dump_stack();
- if (memcg)
- mem_cgroup_print_oom_info(memcg, p);
+ if (oc->memcg)
+ mem_cgroup_print_oom_info(oc->memcg, p);
else
show_mem(SHOW_MEM_FILTER_NODES);
if (sysctl_oom_dump_tasks)
- dump_tasks(memcg, oc->nodemask);
+ dump_tasks(oc->memcg, oc->nodemask);
}
/*
@@ -453,7 +452,7 @@ static bool __oom_reap_task(struct task_struct *tsk)
* We have to make sure to not race with the victim exit path
* and cause premature new oom victim selection:
* __oom_reap_task exit_mm
- * atomic_inc_not_zero
+ * mmget_not_zero
* mmput
* atomic_dec_and_test
* exit_oom_victim
@@ -475,12 +474,22 @@ static bool __oom_reap_task(struct task_struct *tsk)
if (!p)
goto unlock_oom;
mm = p->mm;
- atomic_inc(&mm->mm_users);
+ atomic_inc(&mm->mm_count);
task_unlock(p);
if (!down_read_trylock(&mm->mmap_sem)) {
ret = false;
- goto unlock_oom;
+ goto mm_drop;
+ }
+
+ /*
+ * increase mm_users only after we know we will reap something so
+ * that the mmput_async is called only when we have reaped something
+ * and delayed __mmput doesn't matter that much
+ */
+ if (!mmget_not_zero(mm)) {
+ up_read(&mm->mmap_sem);
+ goto mm_drop;
}
tlb_gather_mmu(&tlb, mm, 0, -1);
@@ -522,15 +531,16 @@ static bool __oom_reap_task(struct task_struct *tsk)
* to release its memory.
*/
set_bit(MMF_OOM_REAPED, &mm->flags);
-unlock_oom:
- mutex_unlock(&oom_lock);
/*
* Drop our reference but make sure the mmput slow path is called from a
* different context because we shouldn't risk we get stuck there and
* put the oom_reaper out of the way.
*/
- if (mm)
- mmput_async(mm);
+ mmput_async(mm);
+mm_drop:
+ mmdrop(mm);
+unlock_oom:
+ mutex_unlock(&oom_lock);
return ret;
}
@@ -739,7 +749,7 @@ void oom_killer_enable(void)
*/
void oom_kill_process(struct oom_control *oc, struct task_struct *p,
unsigned int points, unsigned long totalpages,
- struct mem_cgroup *memcg, const char *message)
+ const char *message)
{
struct task_struct *victim = p;
struct task_struct *child;
@@ -765,7 +775,7 @@ void oom_kill_process(struct oom_control *oc, struct task_struct *p,
task_unlock(p);
if (__ratelimit(&oom_rs))
- dump_header(oc, p, memcg);
+ dump_header(oc, p);
pr_err("%s: Kill process %d (%s) score %u or sacrifice child\n",
message, task_pid_nr(p), p->comm, points);
@@ -786,8 +796,8 @@ void oom_kill_process(struct oom_control *oc, struct task_struct *p,
/*
* oom_badness() returns 0 if the thread is unkillable
*/
- child_points = oom_badness(child, memcg, oc->nodemask,
- totalpages);
+ child_points = oom_badness(child,
+ oc->memcg, oc->nodemask, totalpages);
if (child_points > victim_points) {
put_task_struct(victim);
victim = child;
@@ -865,8 +875,7 @@ void oom_kill_process(struct oom_control *oc, struct task_struct *p,
/*
* Determines whether the kernel must panic because of the panic_on_oom sysctl.
*/
-void check_panic_on_oom(struct oom_control *oc, enum oom_constraint constraint,
- struct mem_cgroup *memcg)
+void check_panic_on_oom(struct oom_control *oc, enum oom_constraint constraint)
{
if (likely(!sysctl_panic_on_oom))
return;
@@ -882,7 +891,7 @@ void check_panic_on_oom(struct oom_control *oc, enum oom_constraint constraint,
/* Do not panic for oom kills triggered by sysrq */
if (is_sysrq_oom(oc))
return;
- dump_header(oc, NULL, memcg);
+ dump_header(oc, NULL);
panic("Out of memory: %s panic_on_oom is enabled\n",
sysctl_panic_on_oom == 2 ? "compulsory" : "system-wide");
}
@@ -957,13 +966,13 @@ bool out_of_memory(struct oom_control *oc)
constraint = constrained_alloc(oc, &totalpages);
if (constraint != CONSTRAINT_MEMORY_POLICY)
oc->nodemask = NULL;
- check_panic_on_oom(oc, constraint, NULL);
+ check_panic_on_oom(oc, constraint);
if (sysctl_oom_kill_allocating_task && current->mm &&
!oom_unkillable_task(current, NULL, oc->nodemask) &&
current->signal->oom_score_adj != OOM_SCORE_ADJ_MIN) {
get_task_struct(current);
- oom_kill_process(oc, current, 0, totalpages, NULL,
+ oom_kill_process(oc, current, 0, totalpages,
"Out of memory (oom_kill_allocating_task)");
return true;
}
@@ -971,12 +980,11 @@ bool out_of_memory(struct oom_control *oc)
p = select_bad_process(oc, &points, totalpages);
/* Found nothing?!?! Either we hang forever, or we panic. */
if (!p && !is_sysrq_oom(oc)) {
- dump_header(oc, NULL, NULL);
+ dump_header(oc, NULL);
panic("Out of memory and no killable processes...\n");
}
if (p && p != (void *)-1UL) {
- oom_kill_process(oc, p, points, totalpages, NULL,
- "Out of memory");
+ oom_kill_process(oc, p, points, totalpages, "Out of memory");
/*
* Give the killed process a good chance to exit before trying
* to allocate memory again.
@@ -988,14 +996,15 @@ bool out_of_memory(struct oom_control *oc)
/*
* The pagefault handler calls here because it is out of memory, so kill a
- * memory-hogging task. If any populated zone has ZONE_OOM_LOCKED set, a
- * parallel oom killing is already in progress so do nothing.
+ * memory-hogging task. If oom_lock is held by somebody else, a parallel oom
+ * killing is already in progress so do nothing.
*/
void pagefault_out_of_memory(void)
{
struct oom_control oc = {
.zonelist = NULL,
.nodemask = NULL,
+ .memcg = NULL,
.gfp_mask = 0,
.order = 0,
};
generated by cgit (git 2.34.1) at 2024-06-11 04:07:43 +0000