From 84e7a2ebb75197f6b2f066c2815add882ff699b8 Mon Sep 17 00:00:00 2001 From: Jim Harris Date: Wed, 31 Oct 2012 17:12:12 +0000 Subject: [PATCH] Pad and align the callout_cpu mtx to its own cacheline to reduce false sharing especially on the default CPU 0 callout_cpu structure. This will be followed up by attilio@ with a conversion to the new struct mtx_padalign but doing this manual conversion first gives an easy MFC candidate since mtx_padalign is a more extensive system change. Sponsored by: Intel Reviewed by: jeff, attilio MFC after: 1 week --- sys/kern/kern_timeout.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sys/kern/kern_timeout.c b/sys/kern/kern_timeout.c index 967d4e0e1d6..a120bd51fe2 100644 --- a/sys/kern/kern_timeout.c +++ b/sys/kern/kern_timeout.c @@ -119,8 +119,8 @@ struct cc_mig_ent { * when the callout should be served. */ struct callout_cpu { - struct cc_mig_ent cc_migrating_entity; struct mtx cc_lock; + struct cc_mig_ent cc_migrating_entity __aligned(CACHE_LINE_SIZE); struct callout *cc_callout; struct callout_tailq *cc_callwheel; struct callout_list cc_callfree;