From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A1CF931F98D; Fri, 12 Jun 2026 10:05:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781258734; cv=none; b=lUFkJAp18KJ4Wr4L7kvprOp4xCVe8cAFnIMGGpeW4JOlsA98gGvoNzOVBsKrKbthtmXsW3hh26jhJeh2XG9okfW6NjIjTHgEUgSfPcxuwN4ackPNbu0YdA02Dd9eZqA/iXh46f5RnOchSdmxibmG7uJY0R/MkjR3AJR1ffa6Mfw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781258734; c=relaxed/simple; bh=z1e+0fsDyx0gid730KgPyhAxRxv42nQreD4mTP/vUcw=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=AZynTdpT2h5BbSIDfEiW3TP0LgUA+oaq3H05QQZ+49naURBfyIMkHBbXMs0tWhiwz2sierh8MgovIXdgPbj8LSYeS6Q+jeBOZCve73276hOJWOyhQpLxciV05jfffCIq/sTDLLpoAeM1EhNTA1A6QU+vPnKBZ2jt1Au+HDIL3rc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=nT8uaQMO; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="nT8uaQMO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D81541F000E9; Fri, 12 Jun 2026 10:05:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1781258733; bh=yb+VaCQXF02BSPuZ+ctVy3j3cdU9RPguQO6IfgOy60Q=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=nT8uaQMODLhBUxROHjXuRd0ltnQkV8xcMmqUgop177jA4Q+qzhzcb7muBVmGixoTP 8p5MM0H4e5+w0xuRc4XmqqID7AuqsXZfUSVh5EXViPm/AAGN08YTt4BXKo01vjLqap y1VHj3PBkZgrrEqAX3vB5we/5Ky0EAj6c94Tly7tR4rCUT9TbNDw/P84YpJ0h7KysQ sg2dDeozJRAbzXf50kjbC8Fp6Q/LuT3OyA+NFO118CfUAPNnbUNKIKON2Kv9Kh6DuN Cow79yOO6yBznJkQotV4LDWWuVTuYqQIHy/HSG1+ag4iVFBOZ/RCPougGXdiQpdFm7 aGVyn4nbo9I+g== Message-ID: <3f53fc18-838f-44ab-acad-4323daa0fbcc@kernel.org> Date: Fri, 12 Jun 2026 12:05:28 +0200 Precedence: bulk X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 11/16] mm/slab: allow kmem_cache_alloc_bulk() with any gfp flags Content-Language: en-US To: Hao Li Cc: Harry Yoo , Christoph Lameter , David Rientjes , Roman Gushchin , Suren Baghdasaryan , Alexei Starovoitov , Andrew Morton , Johannes Weiner , Michal Hocko , Shakeel Butt , Alexander Potapenko , Marco Elver , Dmitry Vyukov , kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org References: <20260610-slab_alloc_flags-v2-0-7190909db118@kernel.org> <20260610-slab_alloc_flags-v2-11-7190909db118@kernel.org> From: "Vlastimil Babka (SUSE)" Autocrypt: addr=vbabka@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 6/12/26 05:21, Hao Li wrote: > On Wed, Jun 10, 2026 at 05:40:13PM +0200, Vlastimil Babka (SUSE) wrote: >> The last user of gfpflags_allow_spinning() in slab is >> alloc_from_pcs_bulk(), which is only called from >> kmem_cache_alloc_bulk(). >> >> It turns out that gfpflags_allow_spinning() is not necessary, because >> kmem_cache_alloc_bulk() is only expected to be called from context that >> does allow spinning, so simply replace it with 'true'. >> >> With that, we can remove the "@flags must allow spinning" part of the >> kernel doc, as there is no more connection to the gfp flags in the slab >> implementation. >> >> Also remove a comment in alloc_slab_obj_exts() because there should be >> no more false positives possible due to gfp_allowed_mask during early >> boot. >> >> Signed-off-by: Vlastimil Babka (SUSE) >> --- >> mm/slub.c | 11 ++--------- >> 1 file changed, 2 insertions(+), 9 deletions(-) >> >> diff --git a/mm/slub.c b/mm/slub.c >> index 0b9974bfcb24..ef457e07db83 100644 >> --- a/mm/slub.c >> +++ b/mm/slub.c >> @@ -2171,12 +2171,6 @@ int alloc_slab_obj_exts(struct slab *slab, struct kmem_cache *s, >> >> sz = obj_exts_alloc_size(s, slab, gfp); >> >> - /* >> - * Note that allow_spin may be false during early boot and its >> - * restricted GFP_BOOT_MASK. Due to kmalloc_nolock() only supporting >> - * architectures with cmpxchg16b, early obj_exts will be missing for >> - * very early allocations on those. >> - */ >> if (unlikely(!allow_spin)) >> vec = kmalloc_nolock(sz, __GFP_ZERO | __GFP_NO_OBJ_EXT, >> slab_nid(slab)); >> @@ -4867,7 +4861,7 @@ unsigned int alloc_from_pcs_bulk(struct kmem_cache *s, gfp_t gfp, size_t size, >> } >> >> full = barn_replace_empty_sheaf(barn, pcs->main, >> - gfpflags_allow_spinning(gfp)); >> + /* allow_spin = */ true); > > we can remove the `gfp` arg as this function no longer use it. True, done!