* Milos Vyletel <mi...@redhat.com> wrote: > On Thu, May 14, 2015 at 01:38:21PM +0200, Jiri Olsa wrote: > > > On Thu, May 14, 2015 at 12:40:59PM +0200, Ingo Molnar wrote: > > > > > > * Milos Vyletel <mi...@redhat.com> wrote: > > > > > > > Use new read/write locks when accesing buildid directory on places where > > > > we may race if multiple instances are run simultaneously. > > > > > > Dunno, this will create locking interaction between multiple instances > > > of perf - hanging each other, etc. > > > > > > And it seems unnecessary: the buildid hierarchy is already spread out. > > > What kind of races might there be? > > > > there was just recently one fixed by commit: > > 0635b0f71424 perf tools: Fix race in build_id_cache__add_s() > > > > havent checked the final patch yet, but the idea is to > > protect us from similar bugs > > right. on top of race with EEXIST couple more are possible (EMLINK, > ENOSPC, EDQUOT, ENOMEM... the only way to prevent them all is to > lock this kind of operations and make sure we run one at a time.
No, that's not the only way to avoid the race - see my previous mail. Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/