The branch main has been updated by mjg:
URL:
https://cgit.FreeBSD.org/src/commit/?id=889a9acc54758922b3529ea473a2dac159d85fd5
commit 889a9acc54758922b3529ea473a2dac159d85fd5
Author: Mateusz Guzik <m...@freebsd.org>
AuthorDate: 2023-02-08 09:53:05 +0000
Commit: Mateusz Guzik <m...@freebsd.org>
CommitDate: 2023-02-16 07:33:51 +0000
ipsec: only update lastused when it changes
to limit cache-line bouncing.
Note that as there is no atomic_store we are hoping the compiler wont
speculatively do the store. It is not employed because the size depends
on target arch.
Sponsored by: Rubicon Communications, LLC ("Netgate")
Differential Revision: https://reviews.freebsd.org/D38433
---
sys/netipsec/key.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/sys/netipsec/key.c b/sys/netipsec/key.c
index 345c302c2a80..62aa99019437 100644
--- a/sys/netipsec/key.c
+++ b/sys/netipsec/key.c
@@ -917,6 +917,7 @@ key_allocsp(struct secpolicyindex *spidx, u_int dir)
struct spdcache_entry *entry, *lastentry, *tmpentry;
struct secpolicy *sp;
uint32_t hashv;
+ time_t ts;
int nb_entries;
if (!SPDCACHE_ACTIVE()) {
@@ -969,7 +970,9 @@ key_allocsp(struct secpolicyindex *spidx, u_int dir)
out:
if (sp != NULL) { /* found a SPD entry */
- sp->lastused = time_second;
+ ts = time_second;
+ if (__predict_false(sp->lastused != ts))
+ sp->lastused = ts;
KEYDBG(IPSEC_STAMP,
printf("%s: return SP(%p)\n", __func__, sp));
KEYDBG(IPSEC_DATA, kdebug_secpolicy(sp));
