perf_counter tools: Add a data file header
Add a data file header so we can transfer data between record and report.
LKML-Reference: <new-submission>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 06fdfb8..2830467 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -51,6 +51,9 @@
static int nr_poll;
static int nr_cpu;
+static int file_new = 1;
+static struct perf_file_header file_header;
+
struct mmap_event {
struct perf_event_header header;
__u32 pid;
@@ -100,6 +103,21 @@
pc->data_tail = tail;
}
+static void write_output(void *buf, size_t size)
+{
+ while (size) {
+ int ret = write(output, buf, size);
+
+ if (ret < 0)
+ die("failed to write");
+
+ size -= ret;
+ buf += ret;
+
+ bytes_written += ret;
+ }
+}
+
static void mmap_read(struct mmap_data *md)
{
unsigned int head = mmap_read_head(md);
@@ -148,34 +166,14 @@
size = md->mask + 1 - (old & md->mask);
old += size;
- while (size) {
- int ret = write(output, buf, size);
-
- if (ret < 0)
- die("failed to write");
-
- size -= ret;
- buf += ret;
-
- bytes_written += ret;
- }
+ write_output(buf, size);
}
buf = &data[old & md->mask];
size = head - old;
old += size;
- while (size) {
- int ret = write(output, buf, size);
-
- if (ret < 0)
- die("failed to write");
-
- size -= ret;
- buf += ret;
-
- bytes_written += ret;
- }
+ write_output(buf, size);
md->prev = old;
mmap_write_tail(md, old);
@@ -204,7 +202,7 @@
struct comm_event comm_ev;
char filename[PATH_MAX];
char bf[BUFSIZ];
- int fd, ret;
+ int fd;
size_t size;
char *field, *sep;
DIR *tasks;
@@ -246,11 +244,7 @@
if (!full) {
comm_ev.tid = pid;
- ret = write(output, &comm_ev, comm_ev.header.size);
- if (ret < 0) {
- perror("failed to write");
- exit(-1);
- }
+ write_output(&comm_ev, comm_ev.header.size);
return;
}
@@ -265,11 +259,7 @@
comm_ev.tid = pid;
- ret = write(output, &comm_ev, comm_ev.header.size);
- if (ret < 0) {
- perror("failed to write");
- exit(-1);
- }
+ write_output(&comm_ev, comm_ev.header.size);
}
closedir(tasks);
return;
@@ -332,10 +322,7 @@
mmap_ev.pid = pid;
mmap_ev.tid = pid;
- if (write(output, &mmap_ev, mmap_ev.header.size) < 0) {
- perror("failed to write");
- exit(-1);
- }
+ write_output(&mmap_ev, mmap_ev.header.size);
}
}
@@ -382,6 +369,15 @@
if (call_graph)
attr->sample_type |= PERF_SAMPLE_CALLCHAIN;
+ if (file_new) {
+ file_header.sample_type = attr->sample_type;
+ } else {
+ if (file_header.sample_type != attr->sample_type) {
+ fprintf(stderr, "incompatible append\n");
+ exit(-1);
+ }
+ }
+
attr->mmap = track;
attr->comm = track;
attr->inherit = (cpu < 0) && inherit;
@@ -461,6 +457,13 @@
nr_cpu++;
}
+static void atexit_header(void)
+{
+ file_header.data_size += bytes_written;
+
+ pwrite(output, &file_header, sizeof(file_header), 0);
+}
+
static int __cmd_record(int argc, const char **argv)
{
int i, counter;
@@ -474,6 +477,10 @@
assert(nr_cpus <= MAX_NR_CPUS);
assert(nr_cpus >= 0);
+ atexit(sig_atexit);
+ signal(SIGCHLD, sig_handler);
+ signal(SIGINT, sig_handler);
+
if (!stat(output_name, &st) && !force && !append_file) {
fprintf(stderr, "Error, output file %s exists, use -A to append or -f to overwrite.\n",
output_name);
@@ -482,7 +489,7 @@
flags = O_CREAT|O_RDWR;
if (append_file)
- flags |= O_APPEND;
+ file_new = 0;
else
flags |= O_TRUNC;
@@ -492,15 +499,18 @@
exit(-1);
}
+ if (!file_new) {
+ read(output, &file_header, sizeof(file_header));
+ lseek(output, file_header.data_size, SEEK_CUR);
+ }
+
+ atexit(atexit_header);
+
if (!system_wide) {
open_counters(-1, target_pid != -1 ? target_pid : getpid());
} else for (i = 0; i < nr_cpus; i++)
open_counters(i, target_pid);
- atexit(sig_atexit);
- signal(SIGCHLD, sig_handler);
- signal(SIGINT, sig_handler);
-
if (target_pid == -1 && argc) {
pid = fork();
if (pid < 0)