diff mbox series

[net-next,1/6] net: mm_account_pinned_pages() optimization

Message ID 20221115091101.2234482-2-edumazet@google.com (mailing list archive)
State Accepted
Commit 57fc05e8e82d015d5d58572e146ac8579a66efea
Delegated to: Netdev Maintainers
Headers show
Series net: more try_cmpxchg() conversions | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 2 this patch: 2
netdev/cc_maintainers success CCed 5 of 5 maintainers
netdev/build_clang success Errors and warnings before: 5 this patch: 5
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 2 this patch: 2
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 15 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Eric Dumazet Nov. 15, 2022, 9:10 a.m. UTC
Adopt atomic_long_try_cmpxchg() in mm_account_pinned_pages()
as it is slightly more efficient.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
---
 net/core/skbuff.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 90d085290d49d864b8431f99a19dbda867d9c03b..4bf95e36ed162611e8245c64c6caeecf9f60ef5d 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -1267,13 +1267,12 @@  int mm_account_pinned_pages(struct mmpin *mmp, size_t size)
 	max_pg = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
 	user = mmp->user ? : current_user();
 
+	old_pg = atomic_long_read(&user->locked_vm);
 	do {
-		old_pg = atomic_long_read(&user->locked_vm);
 		new_pg = old_pg + num_pg;
 		if (new_pg > max_pg)
 			return -ENOBUFS;
-	} while (atomic_long_cmpxchg(&user->locked_vm, old_pg, new_pg) !=
-		 old_pg);
+	} while (!atomic_long_try_cmpxchg(&user->locked_vm, &old_pg, new_pg));
 
 	if (!mmp->user) {
 		mmp->user = get_uid(user);