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charset="UTF-8" X-Stat-Signature: ncxuoj1os3pzxihkmb76atwg5fg44xzz X-Rspam-User: Authentication-Results: imf11.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=hjCPrftM; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (imf11.hostedemail.com: domain of sxwjean@gmail.com designates 209.85.216.47 as permitted sender) smtp.mailfrom=sxwjean@gmail.com X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 3DCA44000F X-HE-Tag: 1654412705-909706 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Sat, Jun 4, 2022 at 5:43 PM Hyeonggon Yoo <42.hyeyoo@gmail.com> wrote: > > On Fri, Jun 03, 2022 at 10:35:55PM +0800, sxwjean@me.com wrote: > > From: Xiongwei Song > > > > There is no need to do anything if sysfs_slab_alias() return nonzero > > value after getting a mergeable cache. > > > > Signed-off-by: Xiongwei Song > > Reviewed-by: Muchun Song > > --- > > v2: Collect Reviewed-by tag from Muchun. > > --- > > mm/slub.c | 8 +++----- > > 1 file changed, 3 insertions(+), 5 deletions(-) > > > > diff --git a/mm/slub.c b/mm/slub.c > > index d8d5abf49f5f..9444277d669a 100644 > > --- a/mm/slub.c > > +++ b/mm/slub.c > > @@ -4861,6 +4861,9 @@ __kmem_cache_alias(const char *name, unsigned int size, unsigned int align, > > > > s = find_mergeable(size, align, flags, name, ctor); > > if (s) { > > + if (sysfs_slab_alias(s, name)) > > + return NULL; > > + > > s->refcount++; > > > > I think we should not expose sysfs attributes before initializing > what can be read via sysfs attribute (object_size). > > > /* > > @@ -4869,11 +4872,6 @@ __kmem_cache_alias(const char *name, unsigned int size, unsigned int align, > > */ > > s->object_size = max(s->object_size, size); > > this calculation should be done before sysfs_slab_alias(). Yeah, understood. Should we restore s->object_size and s->inuse if sysfs_slab_alias() returns non zero value? Regards, Xiongwwei > > Thanks, > Hyeonggon > > > s->inuse = max(s->inuse, ALIGN(size, sizeof(void *))); > > - > > - if (sysfs_slab_alias(s, name)) { > > - s->refcount--; > > - s = NULL; > > - } > > } > > > > return s; > > -- > > 2.30.2 > > >