| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Fri, 27 Mar 2009 14:25:16 +1100
From: Paul Mackerras <paulus@...ba.org>
To: Ingo Molnar <mingo@...e.hu>,
Peter Zijlstra <a.p.zijlstra@...llo.nl>
CC: linux-kernel@...r.kernel.org
Subject: [PATCH 2/2] perf_counter tools: optionally scale counter values in perfstat mode
Impact: new functionality
This adds add an option to the perfstat mode of kerneltop to scale the
reported counter values according to the fraction of time that each
counter gets to count. This is invoked with the -l option (I used 'l'
because s, c, a and e were all taken already.) This uses the new
PERF_RECORD_TOTAL_TIME_{ENABLED,RUNNING} read format options.
With this, we get output like this:
$ ./perfstat -l -e 0:0,0:1,0:2,0:3,0:4,0:5 ./spin
Performance counter stats for './spin':
4016072055 CPU cycles (events) (scaled from 66.53%)
2005887318 instructions (events) (scaled from 66.53%)
1762849 cache references (events) (scaled from 66.69%)
165229 cache misses (events) (scaled from 66.85%)
1001298009 branches (events) (scaled from 66.78%)
41566 branch misses (events) (scaled from 66.61%)
Wall-clock time elapsed: 2438.227446 msecs
This also lets us detect when a counter is zero because the counter
never got to go on the CPU at all. In that case we print <not counted>
rather than 0.
Signed-off-by: Paul Mackerras <paulus@...ba.org>
---
Documentation/perf_counter/kerneltop.c | 55 +++++++++++++++++++++++++------
1 files changed, 44 insertions(+), 11 deletions(-)
diff --git a/Documentation/perf_counter/kerneltop.c b/Documentation/perf_counter/kerneltop.c
index fda1438..54153a9 100644
--- a/Documentation/perf_counter/kerneltop.c
+++ b/Documentation/perf_counter/kerneltop.c
@@ -195,6 +195,8 @@ static int delay_secs = 2;
static int zero;
static int dump_symtab;
+static int scale;
+
struct source_line {
uint64_t EIP;
unsigned long count;
@@ -303,6 +305,7 @@ static void display_perfstat_help(void)
display_events_help();
printf(
+ " -l # scale counter values\n"
" -a # system-wide collection\n");
exit(0);
}
@@ -432,6 +435,9 @@ static void create_perfstat_counter(int counter)
hw_event.config = event_id[counter];
hw_event.record_type = PERF_RECORD_SIMPLE;
hw_event.nmi = 0;
+ if (scale)
+ hw_event.read_format = PERF_FORMAT_TOTAL_TIME_ENABLED |
+ PERF_FORMAT_TOTAL_TIME_RUNNING;
if (system_wide) {
int cpu;
@@ -503,28 +509,53 @@ int do_perfstat(int argc, char *argv[])
fprintf(stderr, "\n");
for (counter = 0; counter < nr_counters; counter++) {
- int cpu;
- __u64 count, single_count;
+ int cpu, nv;
+ __u64 count[3], single_count[3];
+ int scaled;
- count = 0;
+ count[0] = count[1] = count[2] = 0;
+ nv = scale ? 3 : 1;
for (cpu = 0; cpu < nr_cpus; cpu ++) {
res = read(fd[cpu][counter],
- (char *) &single_count, sizeof(single_count));
- assert(res == sizeof(single_count));
- count += single_count;
+ single_count, nv * sizeof(__u64));
+ assert(res == nv * sizeof(__u64));
+
+ count[0] += single_count[0];
+ if (scale) {
+ count[1] += single_count[1];
+ count[2] += single_count[2];
+ }
+ }
+
+ scaled = 0;
+ if (scale) {
+ if (count[2] == 0) {
+ fprintf(stderr, " %14s %-20s\n",
+ "<not counted>", event_name(counter));
+ continue;
+ }
+ if (count[2] < count[1]) {
+ scaled = 1;
+ count[0] = (unsigned long long)
+ ((double)count[0] * count[1] / count[2] + 0.5);
+ }
}
if (event_id[counter] == EID(PERF_TYPE_SOFTWARE, PERF_COUNT_CPU_CLOCK) ||
event_id[counter] == EID(PERF_TYPE_SOFTWARE, PERF_COUNT_TASK_CLOCK)) {
- double msecs = (double)count / 1000000;
+ double msecs = (double)count[0] / 1000000;
- fprintf(stderr, " %14.6f %-20s (msecs)\n",
+ fprintf(stderr, " %14.6f %-20s (msecs)",
msecs, event_name(counter));
} else {
- fprintf(stderr, " %14Ld %-20s (events)\n",
- count, event_name(counter));
+ fprintf(stderr, " %14Ld %-20s (events)",
+ count[0], event_name(counter));
}
+ if (scaled)
+ fprintf(stderr, " (scaled from %.2f%%)",
+ (double) count[2] / count[1] * 100);
+ fprintf(stderr, "\n");
}
fprintf(stderr, "\n");
fprintf(stderr, " Wall-clock time elapsed: %12.6f msecs\n",
@@ -1045,6 +1076,7 @@ static void process_options(int argc, char *argv[])
{"filter", required_argument, NULL, 'f'},
{"group", required_argument, NULL, 'g'},
{"help", no_argument, NULL, 'h'},
+ {"scale", no_argument, NULL, 'l'},
{"nmi", required_argument, NULL, 'n'},
{"pid", required_argument, NULL, 'p'},
{"vmlinux", required_argument, NULL, 'x'},
@@ -1054,7 +1086,7 @@ static void process_options(int argc, char *argv[])
{"mmap_pages", required_argument, NULL, 'm'},
{NULL, 0, NULL, 0 }
};
- int c = getopt_long(argc, argv, "+:ac:C:d:De:f:g:hn:m:p:s:Sx:z",
+ int c = getopt_long(argc, argv, "+:ac:C:d:De:f:g:hln:m:p:s:Sx:z",
long_options, &option_index);
if (c == -1)
break;
@@ -1078,6 +1110,7 @@ static void process_options(int argc, char *argv[])
case 'f': count_filter = atoi(optarg); break;
case 'g': group = atoi(optarg); break;
case 'h': display_help(); break;
+ case 'l': scale = 1; break;
case 'n': nmi = atoi(optarg); break;
case 'p':
/* CPU and PID are mutually exclusive */
--
1.5.5.rc3.7.gba13
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists