From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 D8B131CA87 for ; Wed, 10 Jul 2024 05:38:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720589916; cv=none; b=QTis7x2LvZChy2ZfW5e5oyRDiCU9JHKqErIOCLt7BOCGqHdtJG/LtAQB51q3N22w1M9CQ0wHUo33BagE1wDYKfoN9qHwQvPZ6YZQPvq6gO/IFavfSfrStt2vJ+CkkhmnEtVhEJOE9ezhAq5yQIQRKqUPtSGuzwzYRmXBYZnwlz8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720589916; c=relaxed/simple; bh=it+lZnG8qkE+IDVtq8XvafLTCOle5Ypn5AUBVAIbtok=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=Ob268s3wzF672xg20YRMtfRHNe4jn2plpDRXTrvJ40RI3tFUFHV+p60eQSJgtFoFol5u6JEgIiIUoOdcn55vzBOL9DA/kk6iNikp9qKQnS9Sd4Y6gcXBQPzRtm2eRjdiqHHSYNPRSGVLSUiqZB5+nzfmLTQASbfd28Kalylk7cI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=rwB9O0tj; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="rwB9O0tj" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C8921C32782; Wed, 10 Jul 2024 05:38:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1720589916; bh=it+lZnG8qkE+IDVtq8XvafLTCOle5Ypn5AUBVAIbtok=; h=From:To:Cc:Subject:Date:From; b=rwB9O0tjOmWTH7b+Jobb4sv4nhtpk7dp3Ax0d1ZIjx42t/HjR2M5GLNsv1fftL2kN zJTqVaglzg/nTjChdLWzpUlXfSeeqSubCbh2tZpesARXZXdva3ixJNd5g13MdWe5yi kl8QuazuQv8rdtaF17KI3BCz2fr/Uca838vx0D50bo+7A0H6vjqXMvFMIE11TfHW2Y OtgpGyZAaj5k1UnI7tFWflJ7e9dYziNREcKF8u70Zl5uCaPhHGTUkb41wPNsvimxgq 2xclOoVNqblTybM5rA0p9SbxEdmhaSy2yxFh9ivXh1X1wi02q8QOMLfCJWkum9c3sD ghnib4x0WNQaQ== From: alexs@kernel.org To: Andrew Morton , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Vlastimil Babka , Roman Gushchin , Hyeonggon Yoo <42.hyeyoo@gmail.com>, linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: "Alex Shi (Tencent)" , Randy Dunlap , Yoann Congal , Masahiro Yamada , Petr Mladek , Suren Baghdasaryan Subject: [PATCH v3 1/2] mm/memcg: alignment memcg_data define condition Date: Wed, 10 Jul 2024 13:43:35 +0800 Message-ID: <20240710054336.190410-1-alexs@kernel.org> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: "Alex Shi (Tencent)" commit 21c690a349ba ("mm: introduce slabobj_ext to support slab object extensions") changed the folio/page->memcg_data define condition from MEMCG to SLAB_OBJ_EXT. And selected SLAB_OBJ_EXT for MEMCG, just for SLAB_MATCH(memcg_data, obj_exts), even no other relationship between them. Above action make memcg_data exposed and include SLAB_OBJ_EXT for !MEMCG. That's incorrect in logcial and pay on code size. As Vlastimil Babka suggested, let's add _unused_slab_obj_ext for SLAB_MATCH for slab.obj_exts while !MEMCG. That could resolve the match issue, clean up the feature logical. And decouple the SLAB_OBJ_EXT from MEMCG in next patch. Signed-off-by: Alex Shi (Tencent) Cc: Randy Dunlap Cc: Yoann Congal Cc: Masahiro Yamada Cc: Petr Mladek Cc: Suren Baghdasaryan Cc: Vlastimil Babka --- v1->v3: take Vlastimil's suggestion and move SLAB_OBJ_EXT/MEMCG decouple to 2nd patch. --- include/linux/mm_types.h | 8 ++++++-- mm/slab.h | 4 ++++ 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index ef09c4eef6d3..4ac3abc673d3 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -180,8 +180,10 @@ struct page { /* Usage count. *DO NOT USE DIRECTLY*. See page_ref.h */ atomic_t _refcount; -#ifdef CONFIG_SLAB_OBJ_EXT +#ifdef CONFIG_MEMCG unsigned long memcg_data; +#elif defined(CONFIG_SLAB_OBJ_EXT) + unsigned long _unused_slab_obj_ext; #endif /* @@ -343,8 +345,10 @@ struct folio { }; atomic_t _mapcount; atomic_t _refcount; -#ifdef CONFIG_SLAB_OBJ_EXT +#ifdef CONFIG_MEMCG unsigned long memcg_data; +#elif defined(CONFIG_SLAB_OBJ_EXT) + unsigned long _unused_slab_obj_ext; #endif #if defined(WANT_PAGE_VIRTUAL) void *virtual; diff --git a/mm/slab.h b/mm/slab.h index 3586e6183224..8ffdd4f315f8 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -98,7 +98,11 @@ SLAB_MATCH(flags, __page_flags); SLAB_MATCH(compound_head, slab_cache); /* Ensure bit 0 is clear */ SLAB_MATCH(_refcount, __page_refcount); #ifdef CONFIG_SLAB_OBJ_EXT +#ifdef CONFIG_MEMCG SLAB_MATCH(memcg_data, obj_exts); +#else +SLAB_MATCH(_unused_slab_obj_ext, obj_exts); +#endif #endif #undef SLAB_MATCH static_assert(sizeof(struct slab) <= sizeof(struct page)); -- 2.43.0