path: root/tools/perf/util/symbol-elf.c
diff options
authorArnaldo Carvalho de Melo <acme@redhat.com>2019-12-18 15:23:14 -0300
committerArnaldo Carvalho de Melo <acme@redhat.com>2019-12-20 18:55:40 -0300
commita75af86b6f344f99825cc894596804a91a2ee9cf (patch)
tree78c407a74b7f2a1cdccfc110e960b2866ebaf86d /tools/perf/util/symbol-elf.c
parentperf report: Fix incorrectly added dimensions as switch perf data file (diff)
perf map: Set kmap->kmaps backpointer for main kernel map chunks
When a map is create to represent the main kernel area (vmlinux) with map__new2() we allocate an extra area to store a pointer to the 'struct maps' for the kernel maps, so that we can access that struct when loading ELF files or kallsyms, as we will need to split it in multiple maps, one per kernel module or ELF section (such as ".init.text"). So when map->dso->kernel is non-zero, it is expected that map__kmap(map)->kmaps to be set to the tree of kernel maps (modules, chunks of the main kernel, bpf progs put in place via PERF_RECORD_KSYMBOL, the main kernel). This was not the case when we were splitting the main kernel into chunks for its ELF sections, which ended up making 'perf report --children' processing a perf.data file with callchains to trip on __map__is_kernel(), when we press ENTER to see the popup menu for main histogram entries that starts at a symbol in the ".init.text" ELF section, e.g.: - 8.83% 0.00% swapper [kernel.vmlinux].init.text [k] start_kernel start_kernel cpu_startup_entry do_idle cpuidle_enter cpuidle_enter_state intel_idle Fix it. Reviewed-by: Jiri Olsa <jolsa@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Link: https://lore.kernel.org/lkml/20191218190120.GB13282@kernel.org/ Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to '')
1 files changed, 3 insertions, 0 deletions
diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c
index 6658fbf196e6..1965aefccb02 100644
--- a/tools/perf/util/symbol-elf.c
+++ b/tools/perf/util/symbol-elf.c
@@ -920,6 +920,9 @@ static int dso__process_kernel_symbol(struct dso *dso, struct map *map,
if (curr_map == NULL)
return -1;
+ if (curr_dso->kernel)
+ map__kmap(curr_map)->kmaps = kmaps;
if (adjust_kernel_syms) {
curr_map->start = shdr->sh_addr + ref_reloc(kmap);
curr_map->end = curr_map->start + shdr->sh_size;