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perf_counter: kerneltop: output event support

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Teach kerneltop about the new output ABI.

XXX: anybody fancy integrating the PID/TID data into the output?

Bump the mmap_data pages a little because we bloated the output and
have to be more careful about overruns with structured data.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Orig-LKML-Reference: <20090325113317.192910290@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Peter Zijlstra 2009-03-25 12:30:27 +01:00 committed by Ingo Molnar
parent 4c4ba21d2c
commit 00f0ad73ac
1 changed files with 59 additions and 6 deletions
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65
Documentation/perf_counter/kerneltop.c
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@ -134,6 +134,11 @@
#endif
#define unlikely(x) __builtin_expect(!!(x), 0)
#define min(x, y) ({ \
typeof(x) _min1 = (x); \
typeof(y) _min2 = (y); \
(void) (&_min1 == &_min2); \
_min1 < _min2 ? _min1 : _min2; })
asmlinkage int sys_perf_counter_open(
struct perf_counter_hw_event *hw_event_uptr __user,
@ -178,7 +183,7 @@ static int nr_cpus = 0;
static int nmi = 1;
static int group = 0;
static unsigned int page_size;
static unsigned int mmap_pages = 4;
static unsigned int mmap_pages = 16;
static char *vmlinux;
@ -1147,28 +1152,75 @@ static void mmap_read(struct mmap_data *md)
unsigned int head = mmap_read_head(md);
unsigned int old = md->prev;
unsigned char *data = md->base + page_size;
int diff;
gettimeofday(&this_read, NULL);
if (head - old > md->mask) {
/*
* If we're further behind than half the buffer, there's a chance
* the writer will bite our tail and screw up the events under us.
*
* If we somehow ended up ahead of the head, we got messed up.
*
* In either case, truncate and restart at head.
*/
diff = head - old;
if (diff > md->mask / 2 || diff < 0) {
struct timeval iv;
unsigned long msecs;
timersub(&this_read, &last_read, &iv);
msecs = iv.tv_sec*1000 + iv.tv_usec/1000;
fprintf(stderr, "WARNING: failed to keep up with mmap data. Last read %lu msecs ago.\n", msecs);
fprintf(stderr, "WARNING: failed to keep up with mmap data."
" Last read %lu msecs ago.\n", msecs);
/*
* head points to a known good entry, start there.
*/
old = head;
}
last_read = this_read;
for (; old != head;) {
__u64 *ptr = (__u64 *)&data[old & md->mask];
old += sizeof(__u64);
struct event_struct {
struct perf_event_header header;
__u64 ip;
__u32 pid, tid;
} *event = (struct event_struct *)&data[old & md->mask];
struct event_struct event_copy;
process_event(*ptr, md->counter);
unsigned int size = event->header.size;
/*
* Event straddles the mmap boundary -- header should always
* be inside due to u64 alignment of output.
*/
if ((old & md->mask) + size != ((old + size) & md->mask)) {
unsigned int offset = old;
unsigned int len = sizeof(*event), cpy;
void *dst = &event_copy;
do {
cpy = min(md->mask + 1 - (offset & md->mask), len);
memcpy(dst, &data[offset & md->mask], cpy);
offset += cpy;
dst += cpy;
len -= cpy;
} while (len);
event = &event_copy;
}
old += size;
switch (event->header.type) {
case PERF_EVENT_IP:
case PERF_EVENT_IP | __PERF_EVENT_TID:
process_event(event->ip, md->counter);
break;
}
}
md->prev = old;
@ -1214,6 +1266,7 @@ int main(int argc, char *argv[])
hw_event.irq_period = event_count[counter];
hw_event.record_type = PERF_RECORD_IRQ;
hw_event.nmi = nmi;
hw_event.include_tid = 1;
fd[i][counter] = sys_perf_counter_open(&hw_event, tid, cpu, group_fd, 0);
if (fd[i][counter] < 0) {