Commit 05c82ee3 authored by Suren Baghdasaryan's avatar Suren Baghdasaryan Committed by Andrew Morton
Browse files

alloc_tag: skip pgalloc_tag_swap if profiling is disabled 

When memory allocation profiling is disabled, there is no need to swap
allocation tags during migration.  Skip it to avoid unnecessary overhead.

Once I added these checks, the overhead of the mode when memory profiling
is enabled but turned off went down by about 50%.

Link: https://lkml.kernel.org/r/20241226211639.1357704-2-surenb@google.com


Fixes: e0a955bf ("mm/codetag: add pgalloc_tag_copy()")
Signed-off-by: default avatarSuren Baghdasaryan <surenb@google.com>
Cc: David Wang <00107082@163.com>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Zhenhua Huang <quic_zhenhuah@quicinc.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 9726891f

lib/alloc_tag.c

+3 −0
Original line number Diff line number Diff line
@@ -195,6 +195,9 @@ void pgalloc_tag_swap(struct folio *new, struct folio *old) 
	union codetag_ref ref_old, ref_new;

	struct alloc_tag *tag_old, *tag_new;



	if (!mem_alloc_profiling_enabled())

		return;



	tag_old = pgalloc_tag_get(&old->page);

	if (!tag_old)

		return;