From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 40A8BC2D0DB for ; Mon, 27 Jan 2020 17:39:20 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id F1654214D8 for ; Mon, 27 Jan 2020 17:39:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=fb.com header.i=@fb.com header.b="WB7gspNZ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F1654214D8 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=fb.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 24A686B000D; Mon, 27 Jan 2020 12:39:13 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 1FDE66B026B; Mon, 27 Jan 2020 12:39:13 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 09BAF6B026C; Mon, 27 Jan 2020 12:39:12 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0165.hostedemail.com [216.40.44.165]) by kanga.kvack.org (Postfix) with ESMTP id DE7ED6B000D for ; Mon, 27 Jan 2020 12:39:12 -0500 (EST) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with SMTP id 9DC9734A4 for ; Mon, 27 Jan 2020 17:39:12 +0000 (UTC) X-FDA: 76424125344.28.sky75_6d7632b57fc5c X-HE-Tag: sky75_6d7632b57fc5c X-Filterd-Recvd-Size: 5087 Received: from mx0a-00082601.pphosted.com (mx0a-00082601.pphosted.com [67.231.145.42]) by imf38.hostedemail.com (Postfix) with ESMTP for ; Mon, 27 Jan 2020 17:39:11 +0000 (UTC) Received: from pps.filterd (m0044010.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 00RHal3v022337 for ; Mon, 27 Jan 2020 09:39:11 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-type; s=facebook; bh=zBAjG+wWd0xJyOktTDaZhODl9povKYQlhOgLAcqTSDw=; b=WB7gspNZSTF2X//eu0tIEF/HOGXlzCjHYcCNZ/nh1HD8yiQuAeX49qqOW6Fgjt2sb49Y 3nBTANQS2JbLV3uCK4e7Q7tc/rCUJs0ic2JQiFmFRMVfWRvbPbqHahIaBbf1FeTZHAw9 uOBtSoqiEzEdevWSzuNhALIW85l0SdQc1b8= Received: from mail.thefacebook.com ([163.114.132.120]) by mx0a-00082601.pphosted.com with ESMTP id 2xs6qme7uy-13 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Mon, 27 Jan 2020 09:39:11 -0800 Received: from intmgw001.06.prn3.facebook.com (2620:10d:c085:108::8) by mail.thefacebook.com (2620:10d:c085:11d::7) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1779.2; Mon, 27 Jan 2020 09:39:07 -0800 Received: by devvm2643.prn2.facebook.com (Postfix, from userid 111017) id A9B751DFEFC86; Mon, 27 Jan 2020 09:35:07 -0800 (PST) Smtp-Origin-Hostprefix: devvm From: Roman Gushchin Smtp-Origin-Hostname: devvm2643.prn2.facebook.com To: , Andrew Morton CC: Michal Hocko , Johannes Weiner , Shakeel Butt , Vladimir Davydov , , , Bharata B Rao , Yafang Shao , Roman Gushchin Smtp-Origin-Cluster: prn2c23 Subject: [PATCH v2 11/28] mm: slub: implement SLUB version of obj_to_index() Date: Mon, 27 Jan 2020 09:34:36 -0800 Message-ID: <20200127173453.2089565-12-guro@fb.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200127173453.2089565-1-guro@fb.com> References: <20200127173453.2089565-1-guro@fb.com> X-FB-Internal: Safe MIME-Version: 1.0 Content-Type: text/plain X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.572 definitions=2020-01-27_06:2020-01-24,2020-01-27 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 bulkscore=0 mlxlogscore=999 impostorscore=0 priorityscore=1501 adultscore=0 spamscore=0 phishscore=0 suspectscore=2 mlxscore=0 clxscore=1015 lowpriorityscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1911200001 definitions=main-2001270142 X-FB-Internal: deliver 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: This commit implements SLUB version of the obj_to_index() function, which will be required to calculate the offset of obj_cgroup in the obj_cgroups vector to store/obtain the objcg ownership data. To make it faster, let's repeat the SLAB's trick introduced by commit 6a2d7a955d8d ("[PATCH] SLAB: use a multiply instead of a divide in obj_to_index()") and avoid an expensive division. Signed-off-by: Roman Gushchin Acked-by: Christoph Lameter --- include/linux/slub_def.h | 9 +++++++++ mm/slub.c | 1 + 2 files changed, 10 insertions(+) diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h index d2153789bd9f..200ea292f250 100644 --- a/include/linux/slub_def.h +++ b/include/linux/slub_def.h @@ -8,6 +8,7 @@ * (C) 2007 SGI, Christoph Lameter */ #include +#include enum stat_item { ALLOC_FASTPATH, /* Allocation from cpu slab */ @@ -86,6 +87,7 @@ struct kmem_cache { unsigned long min_partial; unsigned int size; /* The size of an object including metadata */ unsigned int object_size;/* The size of an object without metadata */ + struct reciprocal_value reciprocal_size; unsigned int offset; /* Free pointer offset */ #ifdef CONFIG_SLUB_CPU_PARTIAL /* Number of per cpu partial objects to keep around */ @@ -182,4 +184,11 @@ static inline void *nearest_obj(struct kmem_cache *cache, struct page *page, return result; } +static inline unsigned int obj_to_index(const struct kmem_cache *cache, + const struct page *page, void *obj) +{ + return reciprocal_divide(kasan_reset_tag(obj) - page_address(page), + cache->reciprocal_size); +} + #endif /* _LINUX_SLUB_DEF_H */ diff --git a/mm/slub.c b/mm/slub.c index 503e11b1c4e1..f2fe3a8e420a 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -3598,6 +3598,7 @@ static int calculate_sizes(struct kmem_cache *s, int forced_order) */ size = ALIGN(size, s->align); s->size = size; + s->reciprocal_size = reciprocal_value(size); if (forced_order >= 0) order = forced_order; else -- 2.24.1