This is an automated email from Gerrit.
"Richard Allen <rsa...@gmail.com>" just uploaded a new patch set to Gerrit,
which you can find at https://review.openocd.org/c/openocd/+/8739
-- gerrit
commit 7dd7db6b6d31173a5fcd6125711f34e45d8d97d6
Author: Richard Allen <rsa...@gmail.com>
Date: Mon Feb 3 21:21:15 2025 -0600
target: multiple profiling histograms
Encode profiling data in multiple histograms.
This provides much smaller encoding for target
systems with sparse address maps.
Change-Id: I38276dd1be011ce5781b0264b7cbb09a3aa1a2b5
Signed-off-by: Richard Allen <rsa...@gmail.com>
diff --git a/src/target/target.c b/src/target/target.c
index f47d061903..9db32f8b63 100644
--- a/src/target/target.c
+++ b/src/target/target.c
@@ -4210,13 +4210,13 @@ typedef unsigned char UNIT[2]; /* unit of profiling */
static void write_gmon(const uint32_t *samples, uint32_t sample_num, const
char *filename,
struct target *target, uint32_t duration_ms)
{
- uint32_t i;
-
if (!sample_num) {
LOG_WARNING("no samples to write");
return;
}
+ float sample_rate = sample_num / (duration_ms / 1000.0);
+
FILE *f = fopen(filename, "wb");
if (!f)
return;
@@ -4226,47 +4226,49 @@ static void write_gmon(const uint32_t *samples,
uint32_t sample_num, const char
write_long(f, 0, target); /* padding */
write_long(f, 0, target); /* padding */
- uint8_t zero = 0; /* GMON_TAG_TIME_HIST */
- write_data(f, &zero, 1);
-
- /* figure out bucket size */
- uint32_t min = samples[0];
- /* max should be (largest sample + 1)
- * Refer to binutils/gprof/hist.c (find_histogram_for_pc) */
- uint32_t max = samples[sample_num-1] + 1;
- uint32_t address_space = max - min;
-
- /* FIXME: What is the reasonable number of buckets?
- * The profiling result will be more accurate if there are enough
buckets. */
- static const uint32_t max_buckets = 128 * 1024; /* maximum buckets. */
- uint32_t num_buckets = address_space / sizeof(UNIT);
- if (num_buckets > max_buckets)
- num_buckets = max_buckets;
-
- /* append binary memory gmon.out &profile_hist_hdr
((char*)&profile_hist_hdr + sizeof(struct gmon_hist_hdr)) */
- write_long(f, min, target); /* low_pc */
- write_long(f, max, target); /* high_pc */
- write_long(f, num_buckets, target); /* # of buckets */
- float sample_rate = sample_num / (duration_ms / 1000.0);
- write_long(f, sample_rate, target);
- write_string(f, "seconds");
- for (i = 0; i < (15-strlen("seconds")); i++)
+ while (sample_num) {
+ /* figure out bucket size */
+ uint32_t min = samples[0];
+ uint32_t max = samples[0];
+ uint32_t this_pass = 1;
+ while (this_pass < sample_num && samples[this_pass] - max < 32)
{
+ max = samples[this_pass++];
+ }
+
+ /* max should be (largest sample + 1)
+ * Refer to binutils/gprof/hist.c (find_histogram_for_pc) */
+ max++;
+ uint32_t address_space = max - min;
+
+ uint8_t zero = 0; /* GMON_TAG_TIME_HIST */
write_data(f, &zero, 1);
- write_string(f, "s");
-
- /*append binary memory gmon.out profile_hist_data (profile_hist_data +
profile_hist_hdr.hist_size) */
- uint32_t bidx;
- for (i = 0, bidx = 0; bidx < num_buckets; ++bidx) {
- int val = 0;
- long long bmax = min + (long long)address_space * (bidx + 1) /
num_buckets;
- for ( ; i < sample_num && samples[i] < bmax; ++i)
- if (val < 65535)
- val++;
-
- uint8_t data[2];
- data[0] = val & 0xff;
- data[1] = (val >> 8) & 0xff;
- write_data(f, data, 2);
+
+ /* append binary memory gmon.out &profile_hist_hdr
((char*)&profile_hist_hdr + sizeof(struct gmon_hist_hdr)) */
+ write_long(f, min, target); /* low_pc */
+ write_long(f, max, target); /* high_pc */
+ write_long(f, address_space, target); /* # of buckets */
+ write_long(f, sample_rate, target);
+ write_string(f, "seconds");
+ for (uint32_t i = 0; i < (15-strlen("seconds")); i++)
+ write_data(f, &zero, 1);
+ write_string(f, "s");
+
+ /*append binary memory gmon.out profile_hist_data
(profile_hist_data + profile_hist_hdr.hist_size) */
+ for (uint32_t i = 0, bidx = 0; bidx < address_space; ++bidx) {
+ int val = 0;
+ long long bmax = min + bidx;
+ for ( ; i < this_pass && samples[i] <= bmax; ++i)
+ if (val < 65535)
+ val++;
+
+ uint8_t data[2];
+ data[0] = val & 0xff;
+ data[1] = (val >> 8) & 0xff;
+ write_data(f, data, 2);
+ }
+
+ samples += this_pass;
+ sample_num -= this_pass;
}
fclose(f);
--
