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Date:   Mon,  9 May 2022 20:00:14 -0700
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Subject: [PATCH 3/3] mm: delete unused MMF_OOM_VICTIM flag
From:   Suren Baghdasaryan <surenb@google.com>
To:     akpm@linux-foundation.org
Cc:     mhocko@suse.com, rientjes@google.com, willy@infradead.org,
        hannes@cmpxchg.org, guro@fb.com, minchan@kernel.org,
        kirill@shutemov.name, aarcange@redhat.com, brauner@kernel.org,
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        jannh@google.com, shakeelb@google.com, peterx@redhat.com,
        jhubbard@nvidia.com, shuah@kernel.org,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        linux-kselftest@vger.kernel.org, kernel-team@android.com,
        surenb@google.com
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With the last usage of MMF_OOM_VICTIM in exit_mmap gone, this flag is
now unused and can be removed.

Signed-off-by: Suren Baghdasaryan <surenb@google.com>
---
 include/linux/oom.h            | 9 ---------
 include/linux/sched/coredump.h | 1 -
 mm/oom_kill.c                  | 4 +---
 3 files changed, 1 insertion(+), 13 deletions(-)

diff --git a/include/linux/oom.h b/include/linux/oom.h
index 6cdf0772dbae..25990e9d9e15 100644
--- a/include/linux/oom.h
+++ b/include/linux/oom.h
@@ -77,15 +77,6 @@ static inline bool tsk_is_oom_victim(struct task_struct * tsk)
 	return tsk->signal->oom_mm;
 }
 
-/*
- * Use this helper if tsk->mm != mm and the victim mm needs a special
- * handling. This is guaranteed to stay true after once set.
- */
-static inline bool mm_is_oom_victim(struct mm_struct *mm)
-{
-	return test_bit(MMF_OOM_VICTIM, &mm->flags);
-}
-
 /*
  * Checks whether a page fault on the given mm is still reliable.
  * This is no longer true if the oom reaper started to reap the
diff --git a/include/linux/sched/coredump.h b/include/linux/sched/coredump.h
index 4d9e3a656875..746f6cb07a20 100644
--- a/include/linux/sched/coredump.h
+++ b/include/linux/sched/coredump.h
@@ -70,7 +70,6 @@ static inline int get_dumpable(struct mm_struct *mm)
 #define MMF_UNSTABLE		22	/* mm is unstable for copy_from_user */
 #define MMF_HUGE_ZERO_PAGE	23      /* mm has ever used the global huge zero page */
 #define MMF_DISABLE_THP		24	/* disable THP for all VMAs */
-#define MMF_OOM_VICTIM		25	/* mm is the oom victim */
 #define MMF_OOM_REAP_QUEUED	26	/* mm was queued for oom_reaper */
 #define MMF_MULTIPROCESS	27	/* mm is shared between processes */
 /*
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index 36355b162727..11291b99599f 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -732,10 +732,8 @@ static void mark_oom_victim(struct task_struct *tsk)
 		return;
 
 	/* oom_mm is bound to the signal struct life time. */
-	if (!cmpxchg(&tsk->signal->oom_mm, NULL, mm)) {
+	if (!cmpxchg(&tsk->signal->oom_mm, NULL, mm))
 		mmgrab(tsk->signal->oom_mm);
-		set_bit(MMF_OOM_VICTIM, &mm->flags);
-	}
 
 	/*
 	 * Make sure that the task is woken up from uninterruptible sleep
-- 
2.36.0.512.ge40c2bad7a-goog