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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 50326C4332F for ; Wed, 23 Nov 2022 13:37:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237257AbiKWNh3 (ORCPT ); Wed, 23 Nov 2022 08:37:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43944 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237437AbiKWNgs (ORCPT ); Wed, 23 Nov 2022 08:36:48 -0500 Received: from mail-pl1-x643.google.com (mail-pl1-x643.google.com [IPv6:2607:f8b0:4864:20::643]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EA48164549; Wed, 23 Nov 2022 05:24:48 -0800 (PST) Received: by mail-pl1-x643.google.com with SMTP id jn7so14762132plb.13; Wed, 23 Nov 2022 05:24:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:in-reply-to:references:cc:to :content-language:subject:reply-to:user-agent:mime-version:date :message-id:from:from:to:cc:subject:date:message-id:reply-to; bh=FLcFo0lu8cqSfknNhs9/1pJi0QRuj3g0hxJQsndQlGA=; b=qvpEblmHjoJuXBqj1jvXEdVVi9SSeGBrwDV2Pzsv76fzH+oEb/hTsCcS6zqtr72jvu tTTcUfiVUGgts+22PDTG8vOmQg1vJtZUEy0SabB300imLIUFJmuV5TqDIwmPZiGCWRRW vJtJR+kGOmpvajXyinDQ2oNvvS9nSu/Sk0CjDb8O9Db8Qt0XtxvgoFe00oSsmhjg1JuD duBiBE6Eby3O4uN5RA7IfNcsZWGzFSZQNcaj3jM4AYFhYma1+aYIQC2U5WYjqSFKokpc GLvj8yFD5V8yD8QIYCKUSQDhPESsot/cIPOf5vb7cfd68TUvdAMd2D+eyeCQAJtfE1K4 3PyQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:references:cc:to :content-language:subject:reply-to:user-agent:mime-version:date :message-id:from:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=FLcFo0lu8cqSfknNhs9/1pJi0QRuj3g0hxJQsndQlGA=; b=ka5p5htv0pUnuftuH4Tjf1FxbxmPUph+CpnyOoSz93BLXt9Qr0sKikhhbyvWJdX5+H qWnidLE2igCWf0LO6kpeshG+rEMx0OOabHTGtK9YGFwN+MeCCn3K90ZKk/nM4McJBmEq AcRbry7ocY8XfRAPBHjiDIQqWFqu08R3HP5ajffDM0LZ4aoMVWf4eR2v0Eeq2WpYhOQW zJ24TX8/FD0b5eXiTZYY6TgS1bQhpJdd/NuTqPwezccooUoNPdrVlMWFKSYUcp73iBm5 Op3Lw9X6SF1G4sULIvHr/+rRjrdLG8usQ2KHREorkBva2E291xaFmwh0PDsduAXU15L1 DQNw== X-Gm-Message-State: ANoB5pndesk/avC7JEmB3Xgz+CkrXo5fPGergzqnB2sOBQUCEOXtSEJx cJPIqcsIH3T0Ho/0FaqqbF4= X-Google-Smtp-Source: AA0mqf64Ep5nn2KVBmGe8YMfOk2vbD9JeHTZm/3HvJ2WPkwft1wzJl8LBxIUpNh+bpPhMIxlco/ZhQ== X-Received: by 2002:a17:90b:23cc:b0:218:c83e:476b with SMTP id md12-20020a17090b23cc00b00218c83e476bmr10123836pjb.40.1669209888448; Wed, 23 Nov 2022 05:24:48 -0800 (PST) Received: from [172.18.246.94] ([1.242.215.113]) by smtp.gmail.com with ESMTPSA id j15-20020a170903028f00b001754fa42065sm14167658plr.143.2022.11.23.05.24.46 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 23 Nov 2022 05:24:48 -0800 (PST) From: Sungjong Seo X-Google-Original-From: Sungjong Seo Message-ID: <957dc202-e63e-d039-41c5-092d37a49d1c@samsung.com> Date: Wed, 23 Nov 2022 22:24:40 +0900 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.4.2 Reply-To: sj1557.seo@samsung.com Subject: Re: [PATCH v1 1/5] exfat: reduce the size of exfat_entry_set_cache Content-Language: en-US To: "Yuezhang.Mo@sony.com" , Namjae Jeon Cc: linux-kernel , linux-fsdevel , "Andy.Wu@sony.com" , "Wataru.Aoyama@sony.com" References: In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Yuezhang Mo, > In normal, there are 19 directory entries at most for a file or > a directory. > - A file directory entry > - A stream extension directory entry > - 1~17 file name directory entry > > So the directory entries are in 3 sectors at most, it is enough > for struct exfat_entry_set_cache to pre-allocate 3 bh. > > This commit changes the size of struct exfat_entry_set_cache as: > > Before After > 32-bit system 88 32 bytes > 64-bit system 168 48 bytes > > Signed-off-by: Yuezhang Mo > Reviewed-by: Andy Wu > Reviewed-by: Aoyama Wataru > --- > fs/exfat/exfat_fs.h | 24 ++++++++++++++++++++---- > 1 file changed, 20 insertions(+), 4 deletions(-) > > diff --git a/fs/exfat/exfat_fs.h b/fs/exfat/exfat_fs.h > index a8f8eee4937c..7d2493cda5d8 100644 > --- a/fs/exfat/exfat_fs.h > +++ b/fs/exfat/exfat_fs.h > @@ -9,6 +9,7 @@ > #include > #include > #include > +#include > > #define EXFAT_ROOT_INO 1 > > @@ -41,6 +42,14 @@ enum { > #define ES_2_ENTRIES 2 > #define ES_ALL_ENTRIES 0 > > +#define ES_FILE_ENTRY 0 > +#define ES_STREAM_ENTRY 1 > +#define ES_FIRST_FILENAME_ENTRY 2 New ES_ definitions seem to be an index in an entry set. However, this is confusing with definitions for specifying the range used when obtaining an entry set, such as ES_2_ENTRIES or ES_ALL_ENTRIES. Therefore, it would be better to use ES_IDX_ instead of ES_ to distinguish names such as ES_IDX_FILE, ES_IDX_STREAM and so on. (If you can think of a better prefix, it doesn't have to be ES_IDX_) > +#define EXFAT_FILENAME_ENTRY_NUM(name_len) \ > + DIV_ROUND_UP(name_len, EXFAT_FILE_NAME_LEN) > +#define ES_LAST_FILENAME_ENTRY(name_len) \ > + (ES_FIRST_FILENAME_ENTRY + EXFAT_FILENAME_ENTRY_NUM(name_len)) > + As with the newly defined ES_ value above, it makes sense for the ES_LAST_FILENAME_ENTRY() MACRO to return the index of the last filename entry. So let's subtract 1 from the current MACRO. > #define DIR_DELETED 0xFFFF0321 > > /* type values */ > @@ -68,9 +77,6 @@ enum { > #define MAX_NAME_LENGTH 255 /* max len of file name excluding NULL */ > #define MAX_VFSNAME_BUF_SIZE ((MAX_NAME_LENGTH + 1) * MAX_CHARSET_SIZE) > > -/* Enough size to hold 256 dentry (even 512 Byte sector) */ > -#define DIR_CACHE_SIZE (256*sizeof(struct exfat_dentry)/512+1) > - > #define EXFAT_HINT_NONE -1 > #define EXFAT_MIN_SUBDIR 2 > > @@ -125,6 +131,16 @@ enum { > #define BITS_PER_BYTE_MASK 0x7 > #define IGNORED_BITS_REMAINED(clu, clu_base) ((1 << ((clu) - (clu_base))) - 1) > > +/* 19 entries = 1 file entry + 1 stream entry + 17 filename entries */ > +#define ES_MAX_ENTRY_NUM ES_LAST_FILENAME_ENTRY(MAX_NAME_LENGTH) Of course, it needs to add 1 here. > + > +/* > + * 19 entries x 32 bytes/entry = 608 bytes. > + * The 608 bytes are in 3 sectors at most (even 512 Byte sector). > + */ > +#define DIR_CACHE_SIZE \ > + (DIV_ROUND_UP(EXFAT_DEN_TO_B(ES_MAX_ENTRY_NUM), SECTOR_SIZE) + 1) > + > struct exfat_dentry_namebuf { > char *lfn; > int lfnbuf_len; /* usually MAX_UNINAME_BUF_SIZE */ > @@ -166,11 +182,11 @@ struct exfat_hint { > > struct exfat_entry_set_cache { > struct super_block *sb; > - bool modified; > unsigned int start_off; > int num_bh; > struct buffer_head *bh[DIR_CACHE_SIZE]; > unsigned int num_entries; > + bool modified; > }; > > struct exfat_dir_entry {