path: root/mm/memory.c
diff options
authorJoel Fernandes (Google) <joel@joelfernandes.org>2019-11-30 17:50:33 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2019-12-01 06:29:18 -0800
commite4dcad204d3a281be6f8573e0a82648a4ad84e69 (patch)
tree7c7d4a45f8a84ffe88078ad2def893eb35def96b /mm/memory.c
parentmm: emit tracepoint when RSS changes (diff)
rss_stat: add support to detect RSS updates of external mm
When a process updates the RSS of a different process, the rss_stat tracepoint appears in the context of the process doing the update. This can confuse userspace that the RSS of process doing the update is updated, while in reality a different process's RSS was updated. This issue happens in reclaim paths such as with direct reclaim or background reclaim. This patch adds more information to the tracepoint about whether the mm being updated belongs to the current process's context (curr field). We also include a hash of the mm pointer so that the process who the mm belongs to can be uniquely identified (mm_id field). Also vsprintf.c is refactored a bit to allow reuse of hashing code. [akpm@linux-foundation.org: remove unused local `str'] [joelaf@google.com: inline call to ptr_to_hashval] Link: http://lore.kernel.org/r/20191113153816.14b95acd@gandalf.local.home Link: http://lkml.kernel.org/r/20191114164622.GC233237@google.com Link: http://lkml.kernel.org/r/20191106024452.81923-1-joel@joelfernandes.org Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Reported-by: Ioannis Ilkos <ilkos@google.com> Acked-by: Petr Mladek <pmladek@suse.com> [lib/vsprintf.c] Cc: Tim Murray <timmurray@google.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Carmen Jackson <carmenjackson@google.com> Cc: Mayank Gupta <mayankgupta@google.com> Cc: Daniel Colascione <dancol@google.com> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Minchan Kim <minchan@kernel.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to '')
1 files changed, 2 insertions, 2 deletions
diff --git a/mm/memory.c b/mm/memory.c
index 57c910aaba45..62b5cce653f6 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -154,9 +154,9 @@ static int __init init_zero_pfn(void)
-void mm_trace_rss_stat(int member, long count)
+void mm_trace_rss_stat(struct mm_struct *mm, int member, long count)
- trace_rss_stat(member, count);
+ trace_rss_stat(mm, member, count);