lkml.org 
[lkml]   [2013]   [Jul]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[ 020/103] powerpc/perf: Dont enable if we have zero events
Date
3.10-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Michael Ellerman <michael@ellerman.id.au>

commit 4ea355b5368bde0574c12430df53334c4be3bdcf upstream.

In power_pmu_enable() we still enable the PMU even if we have zero
events. This should have no effect but doesn't make much sense. Instead
just return after telling the hypervisor that we are not using the PMCs.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/powerpc/perf/core-book3s.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

--- a/arch/powerpc/perf/core-book3s.c
+++ b/arch/powerpc/perf/core-book3s.c
@@ -926,6 +926,11 @@ static void power_pmu_enable(struct pmu
if (!cpuhw->disabled)
goto out;

+ if (cpuhw->n_events == 0) {
+ ppc_set_pmu_inuse(0);
+ goto out;
+ }
+
cpuhw->disabled = 0;

/*
@@ -937,8 +942,6 @@ static void power_pmu_enable(struct pmu
if (!cpuhw->n_added) {
mtspr(SPRN_MMCRA, cpuhw->mmcr[2] & ~MMCRA_SAMPLE_ENABLE);
mtspr(SPRN_MMCR1, cpuhw->mmcr[1]);
- if (cpuhw->n_events == 0)
- ppc_set_pmu_inuse(0);
goto out_enable;
}




\
 
 \ /
  Last update: 2013-07-24 01:01    [W:1.160 / U:0.236 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site