[tip:perfcounters/core] perf_counter: Provide hw_perf_counter_setup_online() APIs

tip-bot for Ingo Molnar
2009-08-13T08:40:48Z

Commit-ID: 28402971d869e26271b25301011f667d3a5640c3
Gitweb: http://git.kernel.org/tip/28402971d869e26271b25301011f667d3a5640c3
Author: Ingo Molnar <mingo@elte.hu>
AuthorDate: Thu, 13 Aug 2009 10:13:22 +0200
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Thu, 13 Aug 2009 10:13:22 +0200

perf_counter: Provide hw_perf_counter_setup_online() APIs

Provide weak aliases for hw_perf_counter_setup_online(). This is
used by the BTS patches (for v2.6.32), but it interacts with
fixes so propagate this upstream. (it has no effect as of yet)

Also export perf_counter_output() to architecture code.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

---
include/linux/perf_counter.h | 2 ++
kernel/perf_counter.c | 10 +++++++++-
2 files changed, 11 insertions(+), 1 deletions(-)

diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h
index a9d823a..2b36afe 100644
--- a/include/linux/perf_counter.h
+++ b/include/linux/perf_counter.h
@@ -694,6 +694,8 @@ struct perf_sample_data {

extern int perf_counter_overflow(struct perf_counter *counter, int nmi,
struct perf_sample_data *data);
+extern void perf_counter_output(struct perf_counter *counter, int nmi,
+ struct perf_sample_data *data);

/*
* Return 1 for a software counter, 0 for a hardware counter
diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c
index b0b20a0..e26d2fc 100644
--- a/kernel/perf_counter.c
+++ b/kernel/perf_counter.c
@@ -88,6 +88,7 @@ void __weak hw_perf_disable(void) { barrier(); }
void __weak hw_perf_enable(void) { barrier(); }

void __weak hw_perf_counter_setup(int cpu) { barrier(); }
+void __weak hw_perf_counter_setup_online(int cpu) { barrier(); }

int __weak
hw_perf_group_sched_in(struct perf_counter *group_leader,
@@ -2630,7 +2631,7 @@ static u32 perf_counter_tid(struct perf_counter *counter, struct task_struct *p)
return task_pid_nr_ns(p, counter->ns);
}

-static void perf_counter_output(struct perf_counter *counter, int nmi,
+void perf_counter_output(struct perf_counter *counter, int nmi,
struct perf_sample_data *data)
{
int ret;
@@ -4592,6 +4593,11 @@ perf_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu)
perf_counter_init_cpu(cpu);
break;

+ case CPU_ONLINE:
+ case CPU_ONLINE_FROZEN:
+ hw_perf_counter_setup_online(cpu);
+ break;
+
case CPU_DOWN_PREPARE:
case CPU_DOWN_PREPARE_FROZEN:
perf_counter_exit_cpu(cpu);
@@ -4616,6 +4622,8 @@ void __init perf_counter_init(void)
{
perf_cpu_notify(&perf_cpu_nb, (unsigned long)CPU_UP_PREPARE,
(void *)(long)smp_processor_id());
+ perf_cpu_notify(&perf_cpu_nb, (unsigned long)CPU_ONLINE,
+ (void *)(long)smp_processor_id());
register_cpu_notifier(&perf_cpu_nb);
}