diff mbox series

[06/40] mm: kmem: enable kernel memcg accounting from interrupt contexts

Message ID 20201017231353.tyvwMYEGc%akpm@linux-foundation.org (mailing list archive)
State New, archived
Headers show
Series [01/40] ia64: fix build error with !COREDUMP | expand

Commit Message

Andrew Morton Oct. 17, 2020, 11:13 p.m. UTC
From: Roman Gushchin <guro@fb.com>
Subject: mm: kmem: enable kernel memcg accounting from interrupt contexts

If a memcg to charge can be determined (using remote charging API), there
are no reasons to exclude allocations made from an interrupt context from
the accounting.

Such allocations will pass even if the resulting memcg size will exceed
the hard limit, but it will affect the application of the memory pressure
and an inability to put the workload under the limit will eventually
trigger the OOM.

To use active_memcg() helper, memcg_kmem_bypass() is moved back to
memcontrol.c.

Link: http://lkml.kernel.org/r/20200827225843.1270629-5-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/memcontrol.h |   12 ------------
 mm/memcontrol.c            |   13 +++++++++++++
 2 files changed, 13 insertions(+), 12 deletions(-)
diff mbox series

Patch

--- a/include/linux/memcontrol.h~mm-kmem-enable-kernel-memcg-accounting-from-interrupt-contexts
+++ a/include/linux/memcontrol.h
@@ -1531,18 +1531,6 @@  static inline bool memcg_kmem_enabled(vo
 	return static_branch_likely(&memcg_kmem_enabled_key);
 }
 
-static inline bool memcg_kmem_bypass(void)
-{
-	if (in_interrupt())
-		return true;
-
-	/* Allow remote memcg charging in kthread contexts. */
-	if ((!current->mm || (current->flags & PF_KTHREAD)) &&
-	     !current->active_memcg)
-		return true;
-	return false;
-}
-
 static inline int memcg_kmem_charge_page(struct page *page, gfp_t gfp,
 					 int order)
 {
--- a/mm/memcontrol.c~mm-kmem-enable-kernel-memcg-accounting-from-interrupt-contexts
+++ a/mm/memcontrol.c
@@ -1090,6 +1090,19 @@  static __always_inline struct mem_cgroup
 	return memcg;
 }
 
+static __always_inline bool memcg_kmem_bypass(void)
+{
+	/* Allow remote memcg charging from any context. */
+	if (unlikely(active_memcg()))
+		return false;
+
+	/* Memcg to charge can't be determined. */
+	if (in_interrupt() || !current->mm || (current->flags & PF_KTHREAD))
+		return true;
+
+	return false;
+}
+
 /**
  * If active memcg is set, do not fallback to current->mm->memcg.
  */