perf, amd: Remove the nb lock
Since all the hotplug stuff is serialized by the hotplug mutex,
do away with the amd_nb_lock.
Cc: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/cpu/perf_event_amd.c b/arch/x86/kernel/cpu/perf_event_amd.c
index e421b8c..67e2202 100644
--- a/arch/x86/kernel/cpu/perf_event_amd.c
+++ b/arch/x86/kernel/cpu/perf_event_amd.c
@@ -1,7 +1,5 @@
#ifdef CONFIG_CPU_SUP_AMD
-static DEFINE_RAW_SPINLOCK(amd_nb_lock);
-
static __initconst const u64 amd_hw_cache_event_ids
[PERF_COUNT_HW_CACHE_MAX]
[PERF_COUNT_HW_CACHE_OP_MAX]
@@ -275,7 +273,7 @@
return &emptyconstraint;
}
-static struct amd_nb *amd_alloc_nb(int cpu, int nb_id)
+static struct amd_nb *amd_alloc_nb(int cpu)
{
struct amd_nb *nb;
int i;
@@ -285,7 +283,7 @@
if (!nb)
return NULL;
- nb->nb_id = nb_id;
+ nb->nb_id = -1;
/*
* initialize all possible NB constraints
@@ -306,7 +304,7 @@
if (boot_cpu_data.x86_max_cores < 2)
return NOTIFY_OK;
- cpuc->amd_nb = amd_alloc_nb(cpu, -1);
+ cpuc->amd_nb = amd_alloc_nb(cpu);
if (!cpuc->amd_nb)
return NOTIFY_BAD;
@@ -325,8 +323,6 @@
nb_id = amd_get_nb_id(cpu);
WARN_ON_ONCE(nb_id == BAD_APICID);
- raw_spin_lock(&amd_nb_lock);
-
for_each_online_cpu(i) {
nb = per_cpu(cpu_hw_events, i).amd_nb;
if (WARN_ON_ONCE(!nb))
@@ -341,8 +337,6 @@
cpuc->amd_nb->nb_id = nb_id;
cpuc->amd_nb->refcnt++;
-
- raw_spin_unlock(&amd_nb_lock);
}
static void amd_pmu_cpu_dead(int cpu)
@@ -354,8 +348,6 @@
cpuhw = &per_cpu(cpu_hw_events, cpu);
- raw_spin_lock(&amd_nb_lock);
-
if (cpuhw->amd_nb) {
struct amd_nb *nb = cpuhw->amd_nb;
@@ -364,8 +356,6 @@
cpuhw->amd_nb = NULL;
}
-
- raw_spin_unlock(&amd_nb_lock);
}
static __initconst const struct x86_pmu amd_pmu = {