On 2015/05/15 21:14, Wang Nan wrote:
> Commit 4c859351226c920b227fec040a3b447f0d482af3 ("perf probe: Support
> glob wildcards for function name") introduces a problem:
>
> # /root/perf probe kmem_cache_free
> Failed to find symbol kmem_cache_free in kernel
> Error: Failed to add events.
>
> The reason is the replacement of map__for_each_symbol_by_name() (by
> map__for_each_symbol()). Although their names are similay,
> map__for_each_symbol doesn't call map__load() and dso__sort_by_name()
> before searching. The missing of map__load() causes this problem
> because it search symbol before load dso map.
Oops, yes. But I think we'd better fix map__for_each_symbol() to call
map__load() if the map is not loaded, doesn't it?
Thank you,
>
> This patch ensures map__load() is called before using
> map__for_each_symbol().
>
> After this patch:
>
> # /root/perf probe kmem_cache_free
> Added new event:
> probe:kmem_cache_free (on kmem_cache_free%return)
>
> You can now use it in all perf tools, such as:
>
> perf record -e probe:kmem_cache_free -aR sleep 1
>
> Signed-off-by: Wang Nan <wangn...@huawei.com>
> ---
> tools/perf/util/probe-event.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
> index 2399dc4..1faa1e6 100644
> --- a/tools/perf/util/probe-event.c
> +++ b/tools/perf/util/probe-event.c
> @@ -2499,6 +2499,9 @@ static int find_probe_functions(struct map *map, char
> *name)
> struct symbol *sym;
> struct rb_node *tmp;
>
> + if (map__load(map, NULL) < 0)
> + return 0;
> +
> map__for_each_symbol(map, sym, tmp) {
> if (strglobmatch(sym->name, name))
> found++;
>
--
Masami HIRAMATSU
Linux Technology Research Center, System Productivity Research Dept.
Center for Technology Innovation - Systems Engineering
Hitachi, Ltd., Research & Development Group
E-mail: masami.hiramatsu...@hitachi.com
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