perf tools: Fix tracing info recording

[pandora-kernel.git] / tools / perf / util / header.c

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 6a9c041..76c0b2c 100644 (file)
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -2218,15 +2218,29 @@ int perf_event__synthesize_tracing_data(int fd, struct perf_evlist *evlist,
                                   struct perf_session *session __unused)
 {
        union perf_event ev;
+       struct tracing_data *tdata;
        ssize_t size = 0, aligned_size = 0, padding;
        int err __used = 0;
 
+       /*
+        * We are going to store the size of the data followed
+        * by the data contents. Since the fd descriptor is a pipe,
+        * we cannot seek back to store the size of the data once
+        * we know it. Instead we:
+        *
+        * - write the tracing data to the temp file
+        * - get/write the data size to pipe
+        * - write the tracing data from the temp file
+        *   to the pipe
+        */
+       tdata = tracing_data_get(&evlist->entries, fd, true);
+       if (!tdata)
+               return -1;
+
        memset(&ev, 0, sizeof(ev));
 
        ev.tracing_data.header.type = PERF_RECORD_HEADER_TRACING_DATA;
-       size = read_tracing_data_size(fd, &evlist->entries);
-       if (size <= 0)
-               return size;
+       size = tdata->size;
        aligned_size = ALIGN(size, sizeof(u64));
        padding = aligned_size - size;
        ev.tracing_data.header.size = sizeof(ev.tracing_data);
@@ -2234,7 +2248,12 @@ int perf_event__synthesize_tracing_data(int fd, struct perf_evlist *evlist,
 
        process(&ev, NULL, session);
 
-       err = read_tracing_data(fd, &evlist->entries);
+       /*
+        * The put function will copy all the tracing data
+        * stored in temp file to the pipe.
+        */
+       tracing_data_put(tdata);
+
        write_padded(fd, NULL, 0, padding);
 
        return aligned_size;