mm-commits Archive on lore.kernel.org
 help / color / Atom feed
From: Andrew Morton <akpm@linux-foundation.org>
To: akpm@linux-foundation.org, guro@fb.com, hannes@cmpxchg.org,
	linux-mm@kvack.org, mhocko@kernel.org,
	mm-commits@vger.kernel.org, shakeelb@google.com,
	torvalds@linux-foundation.org
Subject: [patch 03/40] mm: kmem: move memcg_kmem_bypass() calls to get_mem/obj_cgroup_from_current()
Date: Sat, 17 Oct 2020 16:13:44 -0700
Message-ID: <20201017231344.gdtuTtYpQ%akpm@linux-foundation.org> (raw)
In-Reply-To: <20201017161314.88890b87fae7446ccc13c902@linux-foundation.org>

From: Roman Gushchin <guro@fb.com>
Subject: mm: kmem: move memcg_kmem_bypass() calls to get_mem/obj_cgroup_from_current()

Patch series "mm: kmem: kernel memory accounting in an interrupt context".

This patchset implements memcg-based memory accounting of allocations made
from an interrupt context.

Historically, such allocations were passed unaccounted mostly because
charging the memory cgroup of the current process wasn't an option.  Also
performance reasons were likely a reason too.

The remote charging API allows to temporarily overwrite the currently
active memory cgroup, so that all memory allocations are accounted towards
some specified memory cgroup instead of the memory cgroup of the current
process.

This patchset extends the remote charging API so that it can be used from
an interrupt context.  Then it removes the fence that prevented the
accounting of allocations made from an interrupt context.  It also
contains a couple of optimizations/code refactorings.

This patchset doesn't directly enable accounting for any specific
allocations, but prepares the code base for it.  The bpf memory accounting
will likely be the first user of it: a typical example is a bpf program
parsing an incoming network packet, which allocates an entry in hashmap
map to store some information.


This patch (of 4):

Currently memcg_kmem_bypass() is called before obtaining the current
memory/obj cgroup using get_mem/obj_cgroup_from_current().  Moving
memcg_kmem_bypass() into get_mem/obj_cgroup_from_current() reduces the
number of call sites and allows further code simplifications.

Link: http://lkml.kernel.org/r/20200827225843.1270629-1-guro@fb.com
Link: http://lkml.kernel.org/r/20200827225843.1270629-2-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>
---

 mm/memcontrol.c |   13 ++++++++-----
 mm/percpu.c     |    3 +--
 mm/slab.h       |    3 ---
 3 files changed, 9 insertions(+), 10 deletions(-)

--- a/mm/memcontrol.c~mm-kmem-move-memcg_kmem_bypass-calls-to-get_mem-obj_cgroup_from_current
+++ a/mm/memcontrol.c
@@ -1066,6 +1066,9 @@ EXPORT_SYMBOL(get_mem_cgroup_from_page);
  */
 static __always_inline struct mem_cgroup *get_mem_cgroup_from_current(void)
 {
+	if (memcg_kmem_bypass())
+		return NULL;
+
 	if (unlikely(current->active_memcg)) {
 		struct mem_cgroup *memcg;
 
@@ -2933,6 +2936,9 @@ __always_inline struct obj_cgroup *get_o
 	struct obj_cgroup *objcg = NULL;
 	struct mem_cgroup *memcg;
 
+	if (memcg_kmem_bypass())
+		return NULL;
+
 	if (unlikely(!current->mm && !current->active_memcg))
 		return NULL;
 
@@ -3059,19 +3065,16 @@ int __memcg_kmem_charge_page(struct page
 	struct mem_cgroup *memcg;
 	int ret = 0;
 
-	if (memcg_kmem_bypass())
-		return 0;
-
 	memcg = get_mem_cgroup_from_current();
-	if (!mem_cgroup_is_root(memcg)) {
+	if (memcg && !mem_cgroup_is_root(memcg)) {
 		ret = __memcg_kmem_charge(memcg, gfp, 1 << order);
 		if (!ret) {
 			page->mem_cgroup = memcg;
 			__SetPageKmemcg(page);
 			return 0;
 		}
+		css_put(&memcg->css);
 	}
-	css_put(&memcg->css);
 	return ret;
 }
 
--- a/mm/percpu.c~mm-kmem-move-memcg_kmem_bypass-calls-to-get_mem-obj_cgroup_from_current
+++ a/mm/percpu.c
@@ -1584,8 +1584,7 @@ static enum pcpu_chunk_type pcpu_memcg_p
 {
 	struct obj_cgroup *objcg;
 
-	if (!memcg_kmem_enabled() || !(gfp & __GFP_ACCOUNT) ||
-	    memcg_kmem_bypass())
+	if (!memcg_kmem_enabled() || !(gfp & __GFP_ACCOUNT))
 		return PCPU_CHUNK_ROOT;
 
 	objcg = get_obj_cgroup_from_current();
--- a/mm/slab.h~mm-kmem-move-memcg_kmem_bypass-calls-to-get_mem-obj_cgroup_from_current
+++ a/mm/slab.h
@@ -280,9 +280,6 @@ static inline struct obj_cgroup *memcg_s
 {
 	struct obj_cgroup *objcg;
 
-	if (memcg_kmem_bypass())
-		return NULL;
-
 	objcg = get_obj_cgroup_from_current();
 	if (!objcg)
 		return NULL;
_

  parent reply index

Thread overview: 41+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-17 23:13 incoming Andrew Morton
2020-10-17 23:13 ` [patch 01/40] ia64: fix build error with !COREDUMP Andrew Morton
2020-10-17 23:13 ` [patch 02/40] mm, memcg: rework remote charging API to support nesting Andrew Morton
2020-10-17 23:13 ` Andrew Morton [this message]
2020-10-17 23:13 ` [patch 04/40] mm: kmem: remove redundant checks from get_obj_cgroup_from_current() Andrew Morton
2020-10-17 23:13 ` [patch 05/40] mm: kmem: prepare remote memcg charging infra for interrupt contexts Andrew Morton
2020-10-17 23:13 ` [patch 06/40] mm: kmem: enable kernel memcg accounting from " Andrew Morton
2020-10-17 23:13 ` [patch 07/40] mm/memory-failure: remove a wrapper for alloc_migration_target() Andrew Morton
2020-10-17 23:14 ` [patch 08/40] mm/memory_hotplug: " Andrew Morton
2020-10-17 23:14 ` [patch 09/40] mm/migrate: avoid possible unnecessary process right check in kernel_move_pages() Andrew Morton
2020-10-17 23:14 ` [patch 10/40] mm/mmap: add inline vma_next() for readability of mmap code Andrew Morton
2020-10-17 23:14 ` [patch 11/40] mm/mmap: add inline munmap_vma_range() for code readability Andrew Morton
2020-10-17 23:14 ` [patch 12/40] mm/gup_benchmark: take the mmap lock around GUP Andrew Morton
2020-10-17 23:14 ` [patch 13/40] binfmt_elf: take the mmap lock around find_extend_vma() Andrew Morton
2020-10-17 23:14 ` [patch 14/40] mm/gup: assert that the mmap lock is held in __get_user_pages() Andrew Morton
2020-10-17 23:14 ` [patch 15/40] mm/gup_benchmark: rename to mm/gup_test Andrew Morton
2020-10-17 23:14 ` [patch 16/40] selftests/vm: use a common gup_test.h Andrew Morton
2020-10-17 23:14 ` [patch 17/40] selftests/vm: rename run_vmtests --> run_vmtests.sh Andrew Morton
2020-10-17 23:14 ` [patch 18/40] selftests/vm: minor cleanup: Makefile and gup_test.c Andrew Morton
2020-10-17 23:14 ` [patch 19/40] selftests/vm: only some gup_test items are really benchmarks Andrew Morton
2020-10-17 23:14 ` [patch 20/40] selftests/vm: gup_test: introduce the dump_pages() sub-test Andrew Morton
2020-10-17 23:14 ` [patch 21/40] selftests/vm: run_vmtests.sh: update and clean up gup_test invocation Andrew Morton
2020-10-17 23:14 ` [patch 22/40] selftests/vm: hmm-tests: remove the libhugetlbfs dependency Andrew Morton
2020-10-17 23:14 ` [patch 23/40] selftests/vm: 10x speedup for hmm-tests Andrew Morton
2020-10-17 23:14 ` [patch 24/40] mm/madvise: pass mm to do_madvise Andrew Morton
2020-10-17 23:14 ` [patch 25/40] pid: move pidfd_get_pid() to pid.c Andrew Morton
2020-10-17 23:14 ` [patch 26/40] mm/madvise: introduce process_madvise() syscall: an external memory hinting API Andrew Morton
2020-10-17 23:15 ` [patch 27/40] mm: update the documentation for vfree Andrew Morton
2020-10-17 23:15 ` [patch 28/40] mm: add a VM_MAP_PUT_PAGES flag for vmap Andrew Morton
2020-10-17 23:15 ` [patch 29/40] mm: add a vmap_pfn function Andrew Morton
2020-10-17 23:15 ` [patch 30/40] mm: allow a NULL fn callback in apply_to_page_range Andrew Morton
2020-10-17 23:15 ` [patch 31/40] zsmalloc: switch from alloc_vm_area to get_vm_area Andrew Morton
2020-10-17 23:15 ` [patch 32/40] drm/i915: use vmap in shmem_pin_map Andrew Morton
2020-10-17 23:15 ` [patch 33/40] drm/i915: stop using kmap in i915_gem_object_map Andrew Morton
2020-10-17 23:15 ` [patch 34/40] drm/i915: use vmap " Andrew Morton
2020-10-17 23:15 ` [patch 35/40] xen/xenbus: use apply_to_page_range directly in xenbus_map_ring_pv Andrew Morton
2020-10-17 23:15 ` [patch 36/40] x86/xen: open code alloc_vm_area in arch_gnttab_valloc Andrew Morton
2020-10-17 23:15 ` [patch 37/40] mm: remove alloc_vm_area Andrew Morton
2020-10-17 23:15 ` [patch 38/40] mm: cleanup the gfp_mask handling in __vmalloc_area_node Andrew Morton
2020-10-17 23:15 ` [patch 39/40] mm: remove the filename in the top of file comment in vmalloc.c Andrew Morton
2020-10-17 23:15 ` [patch 40/40] mm: remove duplicate include statement in mmu.c Andrew Morton

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20201017231344.gdtuTtYpQ%akpm@linux-foundation.org \
    --to=akpm@linux-foundation.org \
    --cc=guro@fb.com \
    --cc=hannes@cmpxchg.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mhocko@kernel.org \
    --cc=mm-commits@vger.kernel.org \
    --cc=shakeelb@google.com \
    --cc=torvalds@linux-foundation.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

mm-commits Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/mm-commits/0 mm-commits/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 mm-commits mm-commits/ https://lore.kernel.org/mm-commits \
		mm-commits@vger.kernel.org
	public-inbox-index mm-commits

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.mm-commits


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git