[tip:perf/urgent] perf, x86: Use unlocked bitops

From: tip-bot for Peter Zijlstra
Date: Wed Mar 10 2010 - 08:12:47 EST


Commit-ID: 34538ee77b39a12702e0f4c3ed9e8fa2dd5eb92c
Gitweb: http://git.kernel.org/tip/34538ee77b39a12702e0f4c3ed9e8fa2dd5eb92c
Author: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
AuthorDate: Tue, 2 Mar 2010 21:16:55 +0100
Committer: Ingo Molnar <mingo@xxxxxxx>
CommitDate: Wed, 10 Mar 2010 13:22:29 +0100

perf, x86: Use unlocked bitops

There is no concurrency on these variables, so don't use LOCK'ed ops.

As to the intel_pmu_handle_irq() status bit clean, nobody uses that so
remove it all together.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: paulus@xxxxxxxxx
Cc: eranian@xxxxxxxxxx
Cc: robert.richter@xxxxxxx
Cc: fweisbec@xxxxxxxxx
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxxxxx>
LKML-Reference: <20100304140100.240023029@xxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>
---
arch/x86/kernel/cpu/perf_event.c | 8 ++++----
arch/x86/kernel/cpu/perf_event_amd.c | 2 +-
arch/x86/kernel/cpu/perf_event_intel.c | 1 -
3 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index 2dd704f..01b1667 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -643,7 +643,7 @@ static int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign)
if (test_bit(hwc->idx, used_mask))
break;

- set_bit(hwc->idx, used_mask);
+ __set_bit(hwc->idx, used_mask);
if (assign)
assign[i] = hwc->idx;
}
@@ -692,7 +692,7 @@ static int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign)
if (j == X86_PMC_IDX_MAX)
break;

- set_bit(j, used_mask);
+ __set_bit(j, used_mask);

if (assign)
assign[i] = j;
@@ -842,7 +842,7 @@ void hw_perf_enable(void)
* clear active_mask and events[] yet it preserves
* idx
*/
- set_bit(hwc->idx, cpuc->active_mask);
+ __set_bit(hwc->idx, cpuc->active_mask);
cpuc->events[hwc->idx] = event;

x86_pmu.enable(event);
@@ -1057,7 +1057,7 @@ static void x86_pmu_stop(struct perf_event *event)
* Must be done before we disable, otherwise the nmi handler
* could reenable again:
*/
- clear_bit(idx, cpuc->active_mask);
+ __clear_bit(idx, cpuc->active_mask);
x86_pmu.disable(event);

/*
diff --git a/arch/x86/kernel/cpu/perf_event_amd.c b/arch/x86/kernel/cpu/perf_event_amd.c
index 014528b..573458f 100644
--- a/arch/x86/kernel/cpu/perf_event_amd.c
+++ b/arch/x86/kernel/cpu/perf_event_amd.c
@@ -287,7 +287,7 @@ static struct amd_nb *amd_alloc_nb(int cpu, int nb_id)
* initialize all possible NB constraints
*/
for (i = 0; i < x86_pmu.num_events; i++) {
- set_bit(i, nb->event_constraints[i].idxmsk);
+ __set_bit(i, nb->event_constraints[i].idxmsk);
nb->event_constraints[i].weight = 1;
}
return nb;
diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c
index a840948..d87421c 100644
--- a/arch/x86/kernel/cpu/perf_event_intel.c
+++ b/arch/x86/kernel/cpu/perf_event_intel.c
@@ -765,7 +765,6 @@ again:
for_each_set_bit(bit, (unsigned long *)&status, X86_PMC_IDX_MAX) {
struct perf_event *event = cpuc->events[bit];

- clear_bit(bit, (unsigned long *) &status);
if (!test_bit(bit, cpuc->active_mask))
continue;

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