(2012/11/21 6:49), Andrew Morton wrote:
On Mon, 19 Nov 2012 17:44:34 -0800 (PST) David Rientjes <rientjes@xxxxxxxxxx> wrote:While profiling numa/core v16 with cgroup_disable=memory on the command line, I noticed mem_cgroup_count_vm_event() still showed up as high as 0.60% in perftop. This occurs because the function is called extremely often even when memcg is disabled. To fix this, inline the check for mem_cgroup_disabled() so we avoid the unnecessary function call if memcg is disabled. ... diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -181,7 +181,14 @@ unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, gfp_t gfp_mask, unsigned long *total_scanned); -void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx); +void __mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx); +static inline void mem_cgroup_count_vm_event(struct mm_struct *mm, + enum vm_event_item idx) +{ + if (mem_cgroup_disabled() || !mm) + return; + __mem_cgroup_count_vm_event(mm, idx); +}Does the !mm case occur frequently enough to justify inlining it, or should that test remain out-of-line?
I think this should be out-of-line. Thanks, -Kame -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>