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Tue, 14 Jun 2022 01:51:23 -0700 (PDT) Date: Tue, 14 Jun 2022 17:51:17 +0900 From: Hyeonggon Yoo <42.hyeyoo@gmail.com> To: Xiongwei Song Cc: Xiongwei Song , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , Vlastimil Babka , Roman Gushchin , Muchun Song , "linux-mm @ kvack . org" , Linux Kernel Mailing List , Xiongwei Song Subject: Re: [PATCH v2] mm/slub: Simplify __kmem_cache_alias() Message-ID: References: <20220603143555.41914-1-sxwjean@me.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1655196685; a=rsa-sha256; cv=none; b=e4ie7xx1O77YKErN+LMwwy8WJTpRi4w2sJ1izsAHXOXcXl6kGlBcq/S4tt7W4Hg38RzILg uTpMP3qGvorTdwl+61/y0X+7n7w+SIUgB6ylIXWLw4s5sKX22SdubylbkEuIkPbsAf2w4R vN1nHKO2UzsiDR5xZHMGp75Zd+A1XWw= ARC-Authentication-Results: i=1; imf03.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=beZRe95L; spf=pass (imf03.hostedemail.com: domain of 42.hyeyoo@gmail.com designates 209.85.210.174 as permitted sender) smtp.mailfrom=42.hyeyoo@gmail.com; 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> > > 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(). > Sorry for the late reply. > Yeah, understood. Should we restore s->object_size and s->inuse if > sysfs_slab_alias() returns non zero value? In my opinion, yes. Thanks, Hyeonggon > 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 > > > > > -- Thanks, Hyeonggon