+ mm-delete-unused-mmf_oom_victim-flag.patch added to mm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: mm: delete unused MMF_OOM_VICTIM flag
has been added to the -mm mm-unstable branch.  Its filename is
     mm-delete-unused-mmf_oom_victim-flag.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-delete-unused-mmf_oom_victim-flag.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Suren Baghdasaryan <surenb@google.com>
Subject: mm: delete unused MMF_OOM_VICTIM flag
Date: Mon, 16 May 2022 00:56:19 -0700

With the last usage of MMF_OOM_VICTIM in exit_mmap gone, this flag is now
unused and can be removed.

Link: https://lkml.kernel.org/r/20220516075619.1277152-2-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Roman Gushchin <guro@fb.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Christian Brauner (Microsoft) <brauner@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/oom.h            |    9 ---------
 include/linux/sched/coredump.h |    7 +++----
 mm/oom_kill.c                  |    4 +---
 3 files changed, 4 insertions(+), 16 deletions(-)

--- a/include/linux/oom.h~mm-delete-unused-mmf_oom_victim-flag
+++ a/include/linux/oom.h
@@ -78,15 +78,6 @@ static inline bool tsk_is_oom_victim(str
 }
 
 /*
- * 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
  * address space which is reflected by MMF_UNSTABLE flag set in
--- a/include/linux/sched/coredump.h~mm-delete-unused-mmf_oom_victim-flag
+++ a/include/linux/sched/coredump.h
@@ -71,9 +71,8 @@ static inline int get_dumpable(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 */
+#define MMF_OOM_REAP_QUEUED	25	/* mm was queued for oom_reaper */
+#define MMF_MULTIPROCESS	26	/* mm is shared between processes */
 /*
  * MMF_HAS_PINNED: Whether this mm has pinned any pages.  This can be either
  * replaced in the future by mm.pinned_vm when it becomes stable, or grow into
@@ -81,7 +80,7 @@ static inline int get_dumpable(struct mm
  * pinned pages were unpinned later on, we'll still keep this bit set for the
  * lifecycle of this mm, just for simplicity.
  */
-#define MMF_HAS_PINNED		28	/* FOLL_PIN has run, never cleared */
+#define MMF_HAS_PINNED		27	/* FOLL_PIN has run, never cleared */
 #define MMF_DISABLE_THP_MASK	(1 << MMF_DISABLE_THP)
 
 #define MMF_INIT_MASK		(MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK |\
--- a/mm/oom_kill.c~mm-delete-unused-mmf_oom_victim-flag
+++ a/mm/oom_kill.c
@@ -732,10 +732,8 @@ static void mark_oom_victim(struct task_
 		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
_

Patches currently in -mm which might be from surenb@google.com are

selftests-vm-add-process_mrelease-tests.patch
mm-drop-oom-code-from-exit_mmap.patch
mm-delete-unused-mmf_oom_victim-flag.patch