diff mbox series

[net-next,11/20] tcp: small optimization in tcp recvmsg()

Message ID 20211115190249.3936899-12-eric.dumazet@gmail.com (mailing list archive)
State Accepted
Delegated to: Netdev Maintainers
Headers show
Series tcp: optimizations for linux-5.17 | 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 fail Series longer than 15 patches (and no cover letter)
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 warning 2 maintainers not CCed: yoshfuji@linux-ipv6.org dsahern@kernel.org
netdev/build_clang success Errors and warnings before: 22 this patch: 22
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 6 this patch: 6
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 9 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, 2021, 7:02 p.m. UTC 
From: Eric Dumazet <edumazet@google.com>

When reading large chunks of data, incoming packets might
be added to the backlog from BH.

tcp recvmsg() detects the backlog queue is not empty, and uses
a release_sock()/lock_sock() pair to process this backlog.

We now have __sk_flush_backlog() to perform this
a bit faster.

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 net/ipv4/tcp.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 862e8cb8dda51e76300a427783a7d8c32e82cc7f..24d77a32c9cbcdf0e4380ec6d9aa3e42d2cf8730 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2409,8 +2409,7 @@  static int tcp_recvmsg_locked(struct sock *sk, struct msghdr *msg, size_t len,
 
 		if (copied >= target) {
 			/* Do not sleep, just process backlog. */
-			release_sock(sk);
-			lock_sock(sk);
+			__sk_flush_backlog(sk);
 		} else {
 			sk_wait_data(sk, &timeo, last);
 		}