[tip:perf/urgent] perf: Provide generic perf_sample_data initialization

From: tip-bot for Peter Zijlstra
Date: Wed Mar 10 2010 - 08:11:09 EST


Commit-ID: dc1d628a67a8f042e711ea5accc0beedc3ef0092
Gitweb: http://git.kernel.org/tip/dc1d628a67a8f042e711ea5accc0beedc3ef0092
Author: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
AuthorDate: Wed, 3 Mar 2010 15:55:04 +0100
Committer: Ingo Molnar <mingo@xxxxxxx>
CommitDate: Wed, 10 Mar 2010 13:22:23 +0100

perf: Provide generic perf_sample_data initialization

This makes it easier to extend perf_sample_data and fixes a bug on arm
and sparc, which failed to set ->raw to NULL, which can cause crashes
when combined with PERF_SAMPLE_RAW.

It also optimizes PowerPC and tracepoint, because the struct
initialization is forced to zero out the whole structure.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Acked-by: Jean Pihet <jpihet@xxxxxxxxxx>
Reviewed-by: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Acked-by: David S. Miller <davem@xxxxxxxxxxxxx>
Cc: Jamie Iles <jamie.iles@xxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Cc: stable@xxxxxxxxxx
LKML-Reference: <20100304140100.315416040@xxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>
---
arch/arm/kernel/perf_event.c | 4 ++--
arch/powerpc/kernel/perf_event.c | 8 ++++----
arch/sparc/kernel/perf_event.c | 2 +-
arch/x86/kernel/cpu/perf_event.c | 3 +--
arch/x86/kernel/cpu/perf_event_intel.c | 6 ++----
include/linux/perf_event.h | 7 +++++++
kernel/perf_event.c | 21 ++++++++-------------
7 files changed, 25 insertions(+), 26 deletions(-)

diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
index c54ceb3..3875d99 100644
--- a/arch/arm/kernel/perf_event.c
+++ b/arch/arm/kernel/perf_event.c
@@ -965,7 +965,7 @@ armv6pmu_handle_irq(int irq_num,
*/
armv6_pmcr_write(pmcr);

- data.addr = 0;
+ perf_sample_data_init(&data, 0);

cpuc = &__get_cpu_var(cpu_hw_events);
for (idx = 0; idx <= armpmu->num_events; ++idx) {
@@ -1945,7 +1945,7 @@ static irqreturn_t armv7pmu_handle_irq(int irq_num, void *dev)
*/
regs = get_irq_regs();

- data.addr = 0;
+ perf_sample_data_init(&data, 0);

cpuc = &__get_cpu_var(cpu_hw_events);
for (idx = 0; idx <= armpmu->num_events; ++idx) {
diff --git a/arch/powerpc/kernel/perf_event.c b/arch/powerpc/kernel/perf_event.c
index b6cf8f1..5120bd4 100644
--- a/arch/powerpc/kernel/perf_event.c
+++ b/arch/powerpc/kernel/perf_event.c
@@ -1164,10 +1164,10 @@ static void record_and_restart(struct perf_event *event, unsigned long val,
* Finally record data if requested.
*/
if (record) {
- struct perf_sample_data data = {
- .addr = ~0ULL,
- .period = event->hw.last_period,
- };
+ struct perf_sample_data data;
+
+ perf_sample_data_init(&data, ~0ULL);
+ data.period = event->hw.last_period;

if (event->attr.sample_type & PERF_SAMPLE_ADDR)
perf_get_data_addr(regs, &data.addr);
diff --git a/arch/sparc/kernel/perf_event.c b/arch/sparc/kernel/perf_event.c
index 9f2b2ba..6504208 100644
--- a/arch/sparc/kernel/perf_event.c
+++ b/arch/sparc/kernel/perf_event.c
@@ -1189,7 +1189,7 @@ static int __kprobes perf_event_nmi_handler(struct notifier_block *self,

regs = args->regs;

- data.addr = 0;
+ perf_sample_data_init(&data, 0);

cpuc = &__get_cpu_var(cpu_hw_events);

diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index 97cddbf..42aafd1 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -1097,8 +1097,7 @@ static int x86_pmu_handle_irq(struct pt_regs *regs)
int idx, handled = 0;
u64 val;

- data.addr = 0;
- data.raw = NULL;
+ perf_sample_data_init(&data, 0);

cpuc = &__get_cpu_var(cpu_hw_events);

diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c
index 73102df..44b60c8 100644
--- a/arch/x86/kernel/cpu/perf_event_intel.c
+++ b/arch/x86/kernel/cpu/perf_event_intel.c
@@ -590,10 +590,9 @@ static void intel_pmu_drain_bts_buffer(void)

ds->bts_index = ds->bts_buffer_base;

+ perf_sample_data_init(&data, 0);

data.period = event->hw.last_period;
- data.addr = 0;
- data.raw = NULL;
regs.ip = 0;

/*
@@ -742,8 +741,7 @@ static int intel_pmu_handle_irq(struct pt_regs *regs)
int bit, loops;
u64 ack, status;

- data.addr = 0;
- data.raw = NULL;
+ perf_sample_data_init(&data, 0);

cpuc = &__get_cpu_var(cpu_hw_events);

diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 90e0521..6f8cd7d 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -801,6 +801,13 @@ struct perf_sample_data {
struct perf_raw_record *raw;
};

+static inline
+void perf_sample_data_init(struct perf_sample_data *data, u64 addr)
+{
+ data->addr = addr;
+ data->raw = NULL;
+}
+
extern void perf_output_sample(struct perf_output_handle *handle,
struct perf_event_header *header,
struct perf_sample_data *data,
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index e687450..4393b9e 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -4108,8 +4108,7 @@ void __perf_sw_event(u32 event_id, u64 nr, int nmi,
if (rctx < 0)
return;

- data.addr = addr;
- data.raw = NULL;
+ perf_sample_data_init(&data, addr);

do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, nmi, &data, regs);

@@ -4154,11 +4153,10 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
struct perf_event *event;
u64 period;

- event = container_of(hrtimer, struct perf_event, hw.hrtimer);
+ event = container_of(hrtimer, struct perf_event, hw.hrtimer);
event->pmu->read(event);

- data.addr = 0;
- data.raw = NULL;
+ perf_sample_data_init(&data, 0);
data.period = event->hw.last_period;
regs = get_irq_regs();
/*
@@ -4322,17 +4320,15 @@ static const struct pmu perf_ops_task_clock = {
void perf_tp_event(int event_id, u64 addr, u64 count, void *record,
int entry_size)
{
+ struct pt_regs *regs = get_irq_regs();
+ struct perf_sample_data data;
struct perf_raw_record raw = {
.size = entry_size,
.data = record,
};

- struct perf_sample_data data = {
- .addr = addr,
- .raw = &raw,
- };
-
- struct pt_regs *regs = get_irq_regs();
+ perf_sample_data_init(&data, addr);
+ data.raw = &raw;

if (!regs)
regs = task_pt_regs(current);
@@ -4448,8 +4444,7 @@ void perf_bp_event(struct perf_event *bp, void *data)
struct perf_sample_data sample;
struct pt_regs *regs = data;

- sample.raw = NULL;
- sample.addr = bp->attr.bp_addr;
+ perf_sample_data_init(&sample, bp->attr.bp_addr);

if (!perf_exclude_event(bp, regs))
perf_swevent_add(bp, 1, 1, &sample, regs);
--
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