From db555a62feff0566decd992e9b897cf87f4c3fbc Mon Sep 17 00:00:00 2001 From: =?utf8?q?Arkadiusz=20Mi=C5=9Bkiewicz?= Date: Sat, 26 Jan 2019 14:25:50 +0100 Subject: [PATCH] - rel 3; v2 version of the patch --- kernel-small_fixes.patch | 66 ++++++++-------------------------------- kernel.spec | 2 +- 2 files changed, 14 insertions(+), 54 deletions(-) diff --git a/kernel-small_fixes.patch b/kernel-small_fixes.patch index 19610274..c14499f5 100644 --- a/kernel-small_fixes.patch +++ b/kernel-small_fixes.patch @@ -162,10 +162,11 @@ index 76c92e31afc0..abb5d382f64d 100644 -- cgit 1.2-0.3.lf.el7 -From 48744b6339cf649a69b55997e138c17df1ecc897 Mon Sep 17 00:00:00 2001 + +From 9c9e935fc038342c48461aabca666f1b544e32b1 Mon Sep 17 00:00:00 2001 From: Tetsuo Handa -Date: Sat, 26 Jan 2019 20:00:51 +0900 -Subject: [PATCH] oom, oom_reaper: do not enqueue same task twice +Date: Sat, 26 Jan 2019 21:57:25 +0900 +Subject: [PATCH v2] oom, oom_reaper: do not enqueue same task twice Arkadiusz reported that enabling memcg's group oom killing causes strange memcg statistics where there is no task in a memcg despite @@ -182,20 +183,19 @@ request. Fix this bug using an approach used by commit 855b018325737f76 ("oom, oom_reaper: disable oom_reaper for oom_kill_allocating_task"). -Since task_will_free_mem(p) == false if p->mm == NULL, we can assume that -p->mm != NULL when wake_oom_reaper() is called from task_will_free_mem() -paths. As a side effect of this patch, this patch also avoids enqueuing +As a side effect of this patch, this patch also avoids enqueuing multiple threads sharing memory via task_will_free_mem(current) path. Signed-off-by: Tetsuo Handa -Reported-by: Arkadiusz Miśkiewicz +Reported-by: Arkadiusz Miśkiewicz +Tested-by: Arkadiusz Miśkiewicz Fixes: af8e15cc85a25315 ("oom, oom_reaper: do not enqueue task if it is on the oom_reaper_list head") --- - mm/oom_kill.c | 28 +++++++++++++--------------- - 1 file changed, 13 insertions(+), 15 deletions(-) + mm/oom_kill.c | 17 +++++++---------- + 1 file changed, 7 insertions(+), 10 deletions(-) diff --git a/mm/oom_kill.c b/mm/oom_kill.c -index f0e8cd9..457f240 100644 +index f0e8cd9..057bfee 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -505,14 +505,6 @@ bool __oom_reap_task_mm(struct mm_struct *mm) @@ -213,12 +213,9 @@ index f0e8cd9..457f240 100644 for (vma = mm->mmap ; vma; vma = vma->vm_next) { if (!can_madv_dontneed_vma(vma)) continue; -@@ -645,10 +637,15 @@ static int oom_reaper(void *unused) - return 0; - } +@@ -647,8 +639,13 @@ static int oom_reaper(void *unused) --static void wake_oom_reaper(struct task_struct *tsk) -+static void wake_oom_reaper(struct task_struct *tsk, struct mm_struct *mm) + static void wake_oom_reaper(struct task_struct *tsk) { - /* tsk is already queued? */ - if (tsk == oom_reaper_list || tsk->oom_reaper_list) @@ -228,47 +225,10 @@ index f0e8cd9..457f240 100644 + * should imply barriers already and the reader would hit a page fault + * if it stumbled over a reaped memory. + */ -+ if (test_and_set_bit(MMF_UNSTABLE, &mm->flags)) ++ if (test_and_set_bit(MMF_UNSTABLE, &tsk->signal->oom_mm->flags)) return; get_task_struct(tsk); -@@ -668,7 +665,8 @@ static int __init oom_init(void) - } - subsys_initcall(oom_init) - #else --static inline void wake_oom_reaper(struct task_struct *tsk) -+static inline void wake_oom_reaper(struct task_struct *tsk, -+ struct mm_struct *mm) - { - } - #endif /* CONFIG_MMU */ -@@ -915,7 +913,7 @@ static void __oom_kill_process(struct task_struct *victim) - rcu_read_unlock(); - - if (can_oom_reap) -- wake_oom_reaper(victim); -+ wake_oom_reaper(victim, mm); - - mmdrop(mm); - put_task_struct(victim); -@@ -955,7 +953,7 @@ static void oom_kill_process(struct oom_control *oc, const char *message) - task_lock(p); - if (task_will_free_mem(p)) { - mark_oom_victim(p); -- wake_oom_reaper(p); -+ wake_oom_reaper(p, p->mm); - task_unlock(p); - put_task_struct(p); - return; -@@ -1085,7 +1083,7 @@ bool out_of_memory(struct oom_control *oc) - */ - if (task_will_free_mem(current)) { - mark_oom_victim(current); -- wake_oom_reaper(current); -+ wake_oom_reaper(current, current->mm); - return true; - } - -- 1.8.3.1 diff --git a/kernel.spec b/kernel.spec index 551409d6..2bbf62a1 100644 --- a/kernel.spec +++ b/kernel.spec @@ -68,7 +68,7 @@ %define have_pcmcia 0 %endif -%define rel 2 +%define rel 3 %define basever 4.19 %define postver .16 -- 2.44.0