[tip:perfcounters/urgent] perf_counter: Rework the sample ABI

tip-bot for Peter Zijlstra
2009-06-25T19:44:50Z

Commit-ID: e6e18ec79b023d5fe84226cef533cf0e3770ce93
Gitweb: http://git.kernel.org/tip/e6e18ec79b023d5fe84226cef533cf0e3770ce93
Author: Peter Zijlstra <a.p.zijlstra@chello.nl>
AuthorDate: Thu, 25 Jun 2009 11:27:12 +0200
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Thu, 25 Jun 2009 21:39:08 +0200

perf_counter: Rework the sample ABI

The PERF_EVENT_READ implementation made me realize we don't
actually need the sample_type int the output sample, since
we already have that in the perf_counter_attr information.

Therefore, remove the PERF_EVENT_MISC_OVERFLOW bit and the
event->type overloading, and imply put counter overflow
samples in a PERF_EVENT_SAMPLE type.

This also fixes the issue that event->type was only 32-bit
and sample_type had 64 usable bits.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

---
include/linux/perf_counter.h | 10 +++++-----
kernel/perf_counter.c | 36 +++++++++++++++---------------------
tools/perf/builtin-annotate.c | 8 ++++----
tools/perf/builtin-report.c | 32 +++++++++++++++++++-------------
tools/perf/builtin-top.c | 11 ++++++-----
5 files changed, 49 insertions(+), 48 deletions(-)

diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h
index de70a10..3078e23 100644
--- a/include/linux/perf_counter.h
+++ b/include/linux/perf_counter.h
@@ -262,7 +262,6 @@ struct perf_counter_mmap_page {
#define PERF_EVENT_MISC_KERNEL (1 << 0)
#define PERF_EVENT_MISC_USER (2 << 0)
#define PERF_EVENT_MISC_HYPERVISOR (3 << 0)
-#define PERF_EVENT_MISC_OVERFLOW (1 << 2)

struct perf_event_header {
__u32 type;
@@ -348,9 +347,6 @@ enum perf_event_type {
PERF_EVENT_READ = 8,

/*
- * When header.misc & PERF_EVENT_MISC_OVERFLOW the event_type field
- * will be PERF_SAMPLE_*
- *
* struct {
* struct perf_event_header header;
*
@@ -358,8 +354,9 @@ enum perf_event_type {
* { u32 pid, tid; } && PERF_SAMPLE_TID
* { u64 time; } && PERF_SAMPLE_TIME
* { u64 addr; } && PERF_SAMPLE_ADDR
- * { u64 config; } && PERF_SAMPLE_CONFIG
+ * { u64 id; } && PERF_SAMPLE_ID
* { u32 cpu, res; } && PERF_SAMPLE_CPU
+ * { u64 period; } && PERF_SAMPLE_PERIOD
*
* { u64 nr;
* { u64 id, val; } cnt[nr]; } && PERF_SAMPLE_GROUP
@@ -368,6 +365,9 @@ enum perf_event_type {
* u64 ips[nr]; } && PERF_SAMPLE_CALLCHAIN
* };
*/
+ PERF_EVENT_SAMPLE = 9,
+
+ PERF_EVENT_MAX, /* non-ABI */
};

enum perf_callchain_context {
diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c
index 385ca51..f2f2326 100644
--- a/kernel/perf_counter.c
+++ b/kernel/perf_counter.c
@@ -2575,15 +2575,14 @@ static void perf_counter_output(struct perf_counter *counter, int nmi,
u32 cpu, reserved;
} cpu_entry;

- header.type = 0;
+ header.type = PERF_EVENT_SAMPLE;
header.size = sizeof(header);

- header.misc = PERF_EVENT_MISC_OVERFLOW;
+ header.misc = 0;
header.misc |= perf_misc_flags(data->regs);

if (sample_type & PERF_SAMPLE_IP) {
ip = perf_instruction_pointer(data->regs);
- header.type |= PERF_SAMPLE_IP;
header.size += sizeof(ip);
}

@@ -2592,7 +2591,6 @@ static void perf_counter_output(struct perf_counter *counter, int nmi,
tid_entry.pid = perf_counter_pid(counter, current);
tid_entry.tid = perf_counter_tid(counter, current);

- header.type |= PERF_SAMPLE_TID;
header.size += sizeof(tid_entry);
}

@@ -2602,34 +2600,25 @@ static void perf_counter_output(struct perf_counter *counter, int nmi,
*/
time = sched_clock();

- header.type |= PERF_SAMPLE_TIME;
header.size += sizeof(u64);
}

- if (sample_type & PERF_SAMPLE_ADDR) {
- header.type |= PERF_SAMPLE_ADDR;
+ if (sample_type & PERF_SAMPLE_ADDR)
header.size += sizeof(u64);
- }

- if (sample_type & PERF_SAMPLE_ID) {
- header.type |= PERF_SAMPLE_ID;
+ if (sample_type & PERF_SAMPLE_ID)
header.size += sizeof(u64);
- }

if (sample_type & PERF_SAMPLE_CPU) {
- header.type |= PERF_SAMPLE_CPU;
header.size += sizeof(cpu_entry);

cpu_entry.cpu = raw_smp_processor_id();
}

- if (sample_type & PERF_SAMPLE_PERIOD) {
- header.type |= PERF_SAMPLE_PERIOD;
+ if (sample_type & PERF_SAMPLE_PERIOD)
header.size += sizeof(u64);
- }

if (sample_type & PERF_SAMPLE_GROUP) {
- header.type |= PERF_SAMPLE_GROUP;
header.size += sizeof(u64) +
counter->nr_siblings * sizeof(group_entry);
}
@@ -2639,10 +2628,9 @@ static void perf_counter_output(struct perf_counter *counter, int nmi,

if (callchain) {
callchain_size = (1 + callchain->nr) * sizeof(u64);
-
- header.type |= PERF_SAMPLE_CALLCHAIN;
header.size += callchain_size;
- }
+ } else
+ header.size += sizeof(u64);
}

ret = perf_output_begin(&handle, counter, header.size, nmi, 1);
@@ -2693,8 +2681,14 @@ static void perf_counter_output(struct perf_counter *counter, int nmi,
}
}

- if (callchain)
- perf_output_copy(&handle, callchain, callchain_size);
+ if (sample_type & PERF_SAMPLE_CALLCHAIN) {
+ if (callchain)
+ perf_output_copy(&handle, callchain, callchain_size);
+ else {
+ u64 nr = 0;
+ perf_output_put(&handle, nr);
+ }
+ }

perf_output_end(&handle);
}
diff --git a/tools/perf/builtin-annotate.c b/tools/perf/builtin-annotate.c
index 7e58e3a..722c0f5 100644
--- a/tools/perf/builtin-annotate.c
+++ b/tools/perf/builtin-annotate.c
@@ -855,7 +855,7 @@ static unsigned long total = 0,
total_unknown = 0;

static int
-process_overflow_event(event_t *event, unsigned long offset, unsigned long head)
+process_sample_event(event_t *event, unsigned long offset, unsigned long head)
{
char level;
int show = 0;
@@ -1013,10 +1013,10 @@ process_period_event(event_t *event, unsigned long offset, unsigned long head)
static int
process_event(event_t *event, unsigned long offset, unsigned long head)
{
- if (event->header.misc & PERF_EVENT_MISC_OVERFLOW)
- return process_overflow_event(event, offset, head);
-
switch (event->header.type) {
+ case PERF_EVENT_SAMPLE:
+ return process_sample_event(event, offset, head);
+
case PERF_EVENT_MMAP:
return process_mmap_event(event, offset, head);

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index e575f30..ec5361c 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -53,6 +53,8 @@ static regex_t parent_regex;

static int exclude_other = 1;

+static u64 sample_type;
+
struct ip_event {
struct perf_event_header header;
u64 ip;
@@ -1135,7 +1137,7 @@ static int validate_chain(struct ip_callchain *chain, event_t *event)
}

static int
-process_overflow_event(event_t *event, unsigned long offset, unsigned long head)
+process_sample_event(event_t *event, unsigned long offset, unsigned long head)
{
char level;
int show = 0;
@@ -1147,12 +1149,12 @@ process_overflow_event(event_t *event, unsigned long offset, unsigned long head)
void *more_data = event->ip.__more_data;
struct ip_callchain *chain = NULL;

- if (event->header.type & PERF_SAMPLE_PERIOD) {
+ if (sample_type & PERF_SAMPLE_PERIOD) {
period = *(u64 *)more_data;
more_data += sizeof(u64);
}

- dprintf("%p [%p]: PERF_EVENT (IP, %d): %d: %p period: %Ld\n",
+ dprintf("%p [%p]: PERF_EVENT_SAMPLE (IP, %d): %d: %p period: %Ld\n",
(void *)(offset + head),
(void *)(long)(event->header.size),
event->header.misc,
@@ -1160,7 +1162,7 @@ process_overflow_event(event_t *event, unsigned long offset, unsigned long head)
(void *)(long)ip,
(long long)period);

- if (event->header.type & PERF_SAMPLE_CALLCHAIN) {
+ if (sample_type & PERF_SAMPLE_CALLCHAIN) {
int i;

chain = (void *)more_data;
@@ -1352,10 +1354,10 @@ process_event(event_t *event, unsigned long offset, unsigned long head)
{
trace_event(event);

- if (event->header.misc & PERF_EVENT_MISC_OVERFLOW)
- return process_overflow_event(event, offset, head);
-
switch (event->header.type) {
+ case PERF_EVENT_SAMPLE:
+ return process_sample_event(event, offset, head);
+
case PERF_EVENT_MMAP:
return process_mmap_event(event, offset, head);

@@ -1388,18 +1390,21 @@ process_event(event_t *event, unsigned long offset, unsigned long head)

static struct perf_header *header;

-static int perf_header__has_sample(u64 sample_mask)
+static u64 perf_header__sample_type(void)
{
+ u64 sample_type = 0;
int i;

for (i = 0; i < header->attrs; i++) {
struct perf_header_attr *attr = header->attr[i];

- if (!(attr->attr.sample_type & sample_mask))
- return 0;
+ if (!sample_type)
+ sample_type = attr->attr.sample_type;
+ else if (sample_type != attr->attr.sample_type)
+ die("non matching sample_type");
}

- return 1;
+ return sample_type;
}

static int __cmd_report(void)
@@ -1437,8 +1442,9 @@ static int __cmd_report(void)
header = perf_header__read(input);
head = header->data_offset;

- if (sort__has_parent &&
- !perf_header__has_sample(PERF_SAMPLE_CALLCHAIN)) {
+ sample_type = perf_header__sample_type();
+
+ if (sort__has_parent && !(sample_type & PERF_SAMPLE_CALLCHAIN)) {
fprintf(stderr, "selected --sort parent, but no callchain data\n");
exit(-1);
}
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 5352b5e..cf0d21f 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -392,11 +392,11 @@ static void record_ip(u64 ip, int counter)
samples--;
}

-static void process_event(u64 ip, int counter)
+static void process_event(u64 ip, int counter, int user)
{
samples++;

- if (ip < min_ip || ip > max_ip) {
+ if (user) {
userspace_samples++;
return;
}
@@ -509,9 +509,10 @@ static void mmap_read_counter(struct mmap_data *md)

old += size;

- if (event->header.misc & PERF_EVENT_MISC_OVERFLOW) {
- if (event->header.type & PERF_SAMPLE_IP)
- process_event(event->ip.ip, md->counter);
+ if (event->header.type == PERF_EVENT_SAMPLE) {
+ int user =
+ (event->header.misc & PERF_EVENT_MISC_CPUMODE_MASK) == PERF_EVENT_MISC_USER;
+ process_event(event->ip.ip, md->counter, user);
}
}