[PATCH 17/26] perf tools: Synthesize kernel with mmap3

[Jiri Olsa]

Synthesizing kernel with mmap3 events so we can
get build id data for kernel map as well.

Signed-off-by: Jiri Olsa <jo...@kernel.org>
---
 tools/perf/util/synthetic-events.c | 23 ++++++++++++++---------
 1 file changed, 14 insertions(+), 9 deletions(-)

diff --git a/tools/perf/util/synthetic-events.c 
b/tools/perf/util/synthetic-events.c
index 6bd2423ce2f3..844ca87b6e97 100644
--- a/tools/perf/util/synthetic-events.c
+++ b/tools/perf/util/synthetic-events.c
@@ -1029,7 +1029,7 @@ static int __perf_event__synthesize_kernel_mmap(struct 
perf_tool *tool,
         * available use this, and after it is use this as a fallback for older
         * kernels.
         */
-       event = zalloc((sizeof(event->mmap) + machine->id_hdr_size));
+       event = zalloc((sizeof(event->mmap3) + machine->id_hdr_size));
        if (event == NULL) {
                pr_debug("Not enough memory synthesizing mmap event "
                         "for kernel modules\n");
@@ -1046,16 +1046,21 @@ static int __perf_event__synthesize_kernel_mmap(struct 
perf_tool *tool,
                event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL;
        }
 
-       size = snprintf(event->mmap.filename, sizeof(event->mmap.filename),
+       size = snprintf(event->mmap3.filename, sizeof(event->mmap3.filename),
                        "%s%s", machine->mmap_name, kmap->ref_reloc_sym->name) 
+ 1;
        size = PERF_ALIGN(size, sizeof(u64));
-       event->mmap.header.type = PERF_RECORD_MMAP;
-       event->mmap.header.size = (sizeof(event->mmap) -
-                       (sizeof(event->mmap.filename) - size) + 
machine->id_hdr_size);
-       event->mmap.pgoff = kmap->ref_reloc_sym->addr;
-       event->mmap.start = map->start;
-       event->mmap.len   = map->end - event->mmap.start;
-       event->mmap.pid   = machine->pid;
+       event->mmap3.header.type = PERF_RECORD_MMAP3;
+       event->mmap3.header.size = (sizeof(event->mmap3) -
+                       (sizeof(event->mmap3.filename) - size) + 
machine->id_hdr_size);
+       event->mmap3.pgoff = kmap->ref_reloc_sym->addr;
+       event->mmap3.start = map->start;
+       event->mmap3.len   = map->end - event->mmap3.start;
+       event->mmap3.pid   = machine->pid;
+
+       err = sysfs__read_build_id("/sys/kernel/notes", event->mmap3.buildid,
+                                  BUILD_ID_SIZE);
+       if (err)
+               pr_err("Failed to read kernel build ID\n");
 
        err = perf_tool__process_synth_event(tool, event, machine, process);
        free(event);
-- 
2.26.2