From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f42.google.com (mail-pj1-f42.google.com [209.85.216.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 10DD58BF0 for ; Mon, 28 Nov 2022 13:06:22 +0000 (UTC) Received: by mail-pj1-f42.google.com with SMTP id b11so9417252pjp.2 for ; Mon, 28 Nov 2022 05:06:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=B3cwuU9wjQ8VbfKUTNnbiIt2B8/rOnQ22JV6mreBMhw=; b=cPT++xvoRpH851YV9eYArPjV+xqU7oPu2rsB24Yh0VaoiI41HRHpq0BuI5kjhwJxrw OaauRFOykeddywo17as5H5aSfdb3k+ZRK1/HrbhkNJGO6DOeJi2sT+a4VpqYybQDQKis LaIAQLPbv5qwbRMFzzXZCxlxYom4ld5FpVwTHDRB9Kty4D6cM0eXW5bmtRdcMDJj7GSF rw1hW/1qPQQAtN9TTWY17ci9C9wYfKL4g6BZxDPd42udY0AUwikvzlnMDm+UuQjqRGvf uauJd5YIf+vCWVArhUPl5uZt/S+Jx2OzwUCUT7cex60mtf6t3INwYhhhtEWW/CCtmeFX 1Hcg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=B3cwuU9wjQ8VbfKUTNnbiIt2B8/rOnQ22JV6mreBMhw=; b=N4NZarIXzDbLlk1uvZafW81gfhrWOE+M1/budFlpMGPUXYDvpNEb8qWiSlQG4PBxbO /9d85A2OJr6noVSS5aCq9061julZH+Va4GpT3pYIUbz/ZFAA7xoD6QjUfI9YQC1QlyAZ 70kO8Ec6gOiLgByD16GZtz8iJr1qsGyyvUTPkt8jkviQzWOOBtActWXBJ90WsECV9B+R 6vObhN0XCWM6oA38pCrReLtU0B/vklWSZddqd4bpBEFAKY6EoBafKcnxE04AhD77gN2I yee77sS3sUBb2Yc2BygIOY+MaWWxVJWkvPAvjPqKjuTCR3uVFTP3TVJl4+BXmnZkj/w3 0tQQ== X-Gm-Message-State: ANoB5pkCPfE5UC/nnQbqZAhERzweVkbOFQ0T+7JS+E/Dqaporm07z4RB V9MA7b2DGOm5nbcHWAENo7M= X-Google-Smtp-Source: AA0mqf4eYVs0SA4FTr5QWchx8Qk7YnD3lg4y6T/+aoiZj0IfOxBEayp7dPUotwd21M+rJErjpzG5NQ== X-Received: by 2002:a17:90a:7d0d:b0:1fa:b51d:8d83 with SMTP id g13-20020a17090a7d0d00b001fab51d8d83mr32931270pjl.169.1669640782164; Mon, 28 Nov 2022 05:06:22 -0800 (PST) Received: from hyeyoo ([114.29.91.56]) by smtp.gmail.com with ESMTPSA id w13-20020a170902e88d00b00183c67844aesm8889847plg.22.2022.11.28.05.06.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 28 Nov 2022 05:06:21 -0800 (PST) Date: Mon, 28 Nov 2022 22:06:15 +0900 From: Hyeonggon Yoo <42.hyeyoo@gmail.com> To: Vlastimil Babka Cc: Christoph Lameter , David Rientjes , Joonsoo Kim , Pekka Enberg , Roman Gushchin , Andrew Morton , Linus Torvalds , Matthew Wilcox , patches@lists.linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 09/12] mm, slub: split out allocations from pre/post hooks Message-ID: References: <20221121171202.22080-1-vbabka@suse.cz> <20221121171202.22080-10-vbabka@suse.cz> <863dfdbb-2efc-a1d4-3cb1-3edaa67f67bd@suse.cz> Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <863dfdbb-2efc-a1d4-3cb1-3edaa67f67bd@suse.cz> On Mon, Nov 28, 2022 at 12:01:39AM +0100, Vlastimil Babka wrote: > On 11/27/22 11:54, Hyeonggon Yoo wrote: > > On Mon, Nov 21, 2022 at 06:11:59PM +0100, Vlastimil Babka wrote: > >> In the following patch we want to introduce CONFIG_SLUB_TINY allocation > >> paths that don't use the percpu slab. To prepare, refactor the > >> allocation functions: > >> > >> Split out __slab_alloc_node() from slab_alloc_node() where the former > >> does the actual allocation and the latter calls the pre/post hooks. > >> > >> Analogically, split out __kmem_cache_alloc_bulk() from > >> kmem_cache_alloc_bulk(). > >> > >> Signed-off-by: Vlastimil Babka > >> --- > >> mm/slub.c | 127 +++++++++++++++++++++++++++++++++--------------------- > >> 1 file changed, 77 insertions(+), 50 deletions(-) > > > > [...] > > > >> + > >> +/* Note that interrupts must be enabled when calling this function. */ > >> +int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, > >> + void **p) > >> +{ > >> + int i; > >> + struct obj_cgroup *objcg = NULL; > >> + > >> + /* memcg and kmem_cache debug support */ > >> + s = slab_pre_alloc_hook(s, NULL, &objcg, size, flags); > >> + if (unlikely(!s)) > >> + return false; > >> + > >> + i = __kmem_cache_alloc_bulk(s, flags, size, p, objcg); > >> + > >> + /* > >> + * memcg and kmem_cache debug support and memory initialization. > >> + * Done outside of the IRQ disabled fastpath loop. > >> + */ > >> + if (i != 0) > >> + slab_post_alloc_hook(s, objcg, flags, size, p, > >> + slab_want_init_on_alloc(flags, s)); > > > > This patch looks mostly good but wondering what happens if someone calls it with size == 0 > > so it does not call slab_post_alloc_hook()? > > Hmm looks like in that case we miss doing obj_cgroup_put(objcg) in > memcg_slab_post_alloc_hook(). Good catch, thanks! > > Fixing up, also a "return false" from int function > (existed also before this patch). > > ----8<---- > diff --git a/mm/slub.c b/mm/slub.c > index b74c4664160e..88f0ce49caab 100644 > --- a/mm/slub.c > +++ b/mm/slub.c > @@ -3888,10 +3888,13 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, > int i; > struct obj_cgroup *objcg = NULL; > > + if (!size) > + return 0; > + > /* memcg and kmem_cache debug support */ > s = slab_pre_alloc_hook(s, NULL, &objcg, size, flags); > if (unlikely(!s)) > - return false; > + return 0; > > i = __kmem_cache_alloc_bulk(s, flags, size, p, objcg); With that, Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Thanks! -- Thanks, Hyeonggon