[PATCH 15/26] perf tools: Synthesize proc tasks with mmap3

From: Jiri Olsa
Date: Sun Sep 13 2020 - 17:05:04 EST


Synthesizing proc tasks with mmap3 events so we can
get build id data for synthesized maps as well.

Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
tools/perf/util/mmap.c | 2 +-
tools/perf/util/synthetic-events.c | 72 +++++++++++++++++-------------
2 files changed, 43 insertions(+), 31 deletions(-)

diff --git a/tools/perf/util/mmap.c b/tools/perf/util/mmap.c
index ab7108d22428..51f6f86580a9 100644
--- a/tools/perf/util/mmap.c
+++ b/tools/perf/util/mmap.c
@@ -33,7 +33,7 @@ void mmap_cpu_mask__scnprintf(struct mmap_cpu_mask *mask, const char *tag)

len = bitmap_scnprintf(mask->bits, mask->nbits, buf, MASK_SIZE);
buf[len] = '\0';
- pr_debug("%p: %s mask[%zd]: %s\n", mask, tag, mask->nbits, buf);
+ pr_debug2("%p: %s mask[%zd]: %s\n", mask, tag, mask->nbits, buf);
}

size_t mmap__mmap_len(struct mmap *map)
diff --git a/tools/perf/util/synthetic-events.c b/tools/perf/util/synthetic-events.c
index 89b390623b63..bd6e7b84283d 100644
--- a/tools/perf/util/synthetic-events.c
+++ b/tools/perf/util/synthetic-events.c
@@ -379,7 +379,7 @@ int perf_event__synthesize_mmap_events(struct perf_tool *tool,
}
io__init(&io, io.fd, bf, sizeof(bf));

- event->header.type = PERF_RECORD_MMAP2;
+ event->header.type = PERF_RECORD_MMAP3;
t = rdclock();

while (!io.eof) {
@@ -387,20 +387,20 @@ int perf_event__synthesize_mmap_events(struct perf_tool *tool,
size_t size;

/* ensure null termination since stack will be reused. */
- event->mmap2.filename[0] = '\0';
+ event->mmap3.filename[0] = '\0';

/* 00400000-0040c000 r-xp 00000000 fd:01 41038 /bin/cat */
if (!read_proc_maps_line(&io,
- &event->mmap2.start,
- &event->mmap2.len,
- &event->mmap2.prot,
- &event->mmap2.flags,
- &event->mmap2.pgoff,
- &event->mmap2.maj,
- &event->mmap2.min,
- &event->mmap2.ino,
- sizeof(event->mmap2.filename),
- event->mmap2.filename))
+ &event->mmap3.start,
+ &event->mmap3.len,
+ &event->mmap3.prot,
+ &event->mmap3.flags,
+ &event->mmap3.pgoff,
+ &event->mmap3.maj,
+ &event->mmap3.min,
+ &event->mmap3.ino,
+ sizeof(event->mmap3.filename),
+ event->mmap3.filename))
continue;

if ((rdclock() - t) > timeout) {
@@ -412,7 +412,7 @@ int perf_event__synthesize_mmap_events(struct perf_tool *tool,
goto out;
}

- event->mmap2.ino_generation = 0;
+ event->mmap3.ino_generation = 0;

/*
* Just like the kernel, see __perf_event_mmap in kernel/perf_event.c
@@ -422,8 +422,8 @@ int perf_event__synthesize_mmap_events(struct perf_tool *tool,
else
event->header.misc = PERF_RECORD_MISC_GUEST_USER;

- if ((event->mmap2.prot & PROT_EXEC) == 0) {
- if (!mmap_data || (event->mmap2.prot & PROT_READ) == 0)
+ if ((event->mmap3.prot & PROT_EXEC) == 0) {
+ if (!mmap_data || (event->mmap3.prot & PROT_READ) == 0)
continue;

event->header.misc |= PERF_RECORD_MISC_MMAP_DATA;
@@ -433,25 +433,37 @@ int perf_event__synthesize_mmap_events(struct perf_tool *tool,
if (truncation)
event->header.misc |= PERF_RECORD_MISC_PROC_MAP_PARSE_TIMEOUT;

- if (!strcmp(event->mmap2.filename, ""))
- strcpy(event->mmap2.filename, anonstr);
+ if (!strcmp(event->mmap3.filename, ""))
+ strcpy(event->mmap3.filename, anonstr);

if (hugetlbfs_mnt_len &&
- !strncmp(event->mmap2.filename, hugetlbfs_mnt,
+ !strncmp(event->mmap3.filename, hugetlbfs_mnt,
hugetlbfs_mnt_len)) {
- strcpy(event->mmap2.filename, anonstr);
- event->mmap2.flags |= MAP_HUGETLB;
+ strcpy(event->mmap3.filename, anonstr);
+ event->mmap3.flags |= MAP_HUGETLB;
}

- size = strlen(event->mmap2.filename) + 1;
+ size = strlen(event->mmap3.filename) + 1;
size = PERF_ALIGN(size, sizeof(u64));
- event->mmap2.len -= event->mmap.start;
- event->mmap2.header.size = (sizeof(event->mmap2) -
- (sizeof(event->mmap2.filename) - size));
- memset(event->mmap2.filename + size, 0, machine->id_hdr_size);
- event->mmap2.header.size += machine->id_hdr_size;
- event->mmap2.pid = tgid;
- event->mmap2.tid = pid;
+ event->mmap3.len -= event->mmap.start;
+ event->mmap3.header.size = (sizeof(event->mmap3) -
+ (sizeof(event->mmap3.filename) - size));
+ memset(event->mmap3.filename + size, 0, machine->id_hdr_size);
+ event->mmap3.header.size += machine->id_hdr_size;
+ event->mmap3.pid = tgid;
+ event->mmap3.tid = pid;
+
+ rc = filename__read_build_id(event->mmap3.filename, event->mmap3.buildid,
+ BUILD_ID_SIZE);
+ if (rc != BUILD_ID_SIZE) {
+ if (event->mmap3.filename[0] == '/') {
+ pr_debug2("Failed to read build ID for %s\n",
+ event->mmap3.filename);
+ }
+ memset(event->mmap3.buildid, 0x0, sizeof(event->mmap3.buildid));
+ }
+
+ rc = 0;

if (perf_tool__process_synth_event(tool, event, machine, process) != 0) {
rc = -1;
@@ -744,7 +756,7 @@ int perf_event__synthesize_thread_map(struct perf_tool *tool,
if (comm_event == NULL)
goto out;

- mmap_event = malloc(sizeof(mmap_event->mmap2) + machine->id_hdr_size);
+ mmap_event = malloc(sizeof(mmap_event->mmap3) + machine->id_hdr_size);
if (mmap_event == NULL)
goto out_free_comm;

@@ -826,7 +838,7 @@ static int __perf_event__synthesize_threads(struct perf_tool *tool,
if (comm_event == NULL)
goto out;

- mmap_event = malloc(sizeof(mmap_event->mmap2) + machine->id_hdr_size);
+ mmap_event = malloc(sizeof(mmap_event->mmap3) + machine->id_hdr_size);
if (mmap_event == NULL)
goto out_free_comm;

--
2.26.2