Re: [PATCH] powerpc/mm: Add trace point for tracking hash pte fault
From: Aneesh Kumar K.V <hidden>
Date: 2015-02-02 16:22:21
From: Aneesh Kumar K.V <hidden>
Date: 2015-02-02 16:22:21
Anton Blanchard [off-list ref] writes:
Hi,quoted
quoted
ebizzy with -S 30 -t 1 -P gave 13627 records/s -> Without patch 13546 records/s -> With patch with tracepoint disabledOK. So that's about -0.6%. Are we happy with that? I'm not sure. Can you do a few more runs and see if that's a stable result.Surprisingly large. Is CONFIG_JUMP_LABEL enabled? That should reduce the tracepoint to just a nop.
yes. We do use jump label. I also verified that looking at .s
#APP
# 23 "./arch/powerpc/include/asm/jump_label.h" 1
1:
nop
.pushsection __jump_table, "aw"
.llong 1b, .L201, __tracepoint_hash_fault+8 #,
.popsection
# 0 "" 2
.....
-aneesh