Re: [PATCH] perf machine: Search for modules in %s/lib/modules/%s

From: Namhyung Kim
Date: Tue Apr 29 2014 - 19:46:47 EST


Hi Jiri,

On Tue, 29 Apr 2014 10:06:17 +0200, Jiri Olsa wrote:
> On Sun, Apr 27, 2014 at 12:05:56PM +0200, Jiri Olsa wrote:
>> On Sat, Apr 26, 2014 at 01:17:55PM -0400, Richard Yao wrote:
>> > Modules installed outside of the kernel's build system should go into
>> > "%s/lib/modules/%s/extra", but at present, perf will only look at them
>> > when they are in "%s/lib/modules/%s/kernel". Lets encourage good
>> > citizenship by relaxing this requirement to "%s/lib/modules/%s". This
>> > way open source modules that are out-of-tree have no incentive to start
>> > populating a directory reserved for in-kernel modules and I can stop
>> > hex-editing my system's perf binary when profiling OSS out-of-tree
>> > modules.
>> >
>> > Feedback from Namhyung Kim correctly revealed that the hex-edits that I
>> > had been doing meant that perf was also traversing the build and source
>> > symlinks in %s/lib/modules/%s. That is undesireable, so we explicitly
>> > exclude them from traversal with a minor tweak to the traversal routine.
>>
>> looks good to me, Namhyung?
>
> just realized Namhyung wasn't CC-ed on this one ;-)

:)

Well, I still prefer the symlink check with lstat(), I can live with
this, so:

Acked-by: Namhyung kim <namhyung@xxxxxxxxxx>

Thanks,
Namhyung

>
>>
>> thanks,
>> jirka
>>
>> >
>> > Signed-off-by: Richard Yao <ryao@xxxxxxxxxx>
>> > ---
>> > tools/perf/util/machine.c | 16 ++++++++++++----
>> > 1 file changed, 12 insertions(+), 4 deletions(-)
>> >
>> > diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
>> > index a53cd0b..27c2a5e 100644
>> > --- a/tools/perf/util/machine.c
>> > +++ b/tools/perf/util/machine.c
>> > @@ -717,7 +717,7 @@ static char *get_kernel_version(const char *root_dir)
>> > }
>> >
>> > static int map_groups__set_modules_path_dir(struct map_groups *mg,
>> > - const char *dir_name)
>> > + const char *dir_name, int depth)
>> > {
>> > struct dirent *dent;
>> > DIR *dir = opendir(dir_name);
>> > @@ -742,7 +742,15 @@ static int map_groups__set_modules_path_dir(struct map_groups *mg,
>> > !strcmp(dent->d_name, ".."))
>> > continue;
>> >
>> > - ret = map_groups__set_modules_path_dir(mg, path);
>> > + /* Do not follow top-level source and build symlinks */
>> > + if (depth == 0) {
>> > + if (!strcmp(dent->d_name, "source") ||
>> > + !strcmp(dent->d_name, "build"))
>> > + continue;
>> > + }
>> > +
>> > + ret = map_groups__set_modules_path_dir(mg, path,
>> > + depth + 1);
>> > if (ret < 0)
>> > goto out;
>> > } else {
>> > @@ -786,11 +794,11 @@ static int machine__set_modules_path(struct machine *machine)
>> > if (!version)
>> > return -1;
>> >
>> > - snprintf(modules_path, sizeof(modules_path), "%s/lib/modules/%s/kernel",
>> > + snprintf(modules_path, sizeof(modules_path), "%s/lib/modules/%s",
>> > machine->root_dir, version);
>> > free(version);
>> >
>> > - return map_groups__set_modules_path_dir(&machine->kmaps, modules_path);
>> > + return map_groups__set_modules_path_dir(&machine->kmaps, modules_path, 0);
>> > }
>> >
>> > static int machine__create_module(void *arg, const char *name, u64 start)
>> > --
>> > 1.8.3.2
>> >
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@xxxxxxxxxxxxxxx
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at http://www.tux.org/lkml/
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/