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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 17034C433F5 for ; Tue, 17 May 2022 09:17:12 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A42D46B0072; Tue, 17 May 2022 05:17:11 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9F11A6B0074; Tue, 17 May 2022 05:17:11 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8BA298D0001; Tue, 17 May 2022 05:17:11 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 803926B0072 for ; Tue, 17 May 2022 05:17:11 -0400 (EDT) Received: from smtpin29.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 5D1702099C for ; Tue, 17 May 2022 09:17:11 +0000 (UTC) X-FDA: 79474681062.29.9994423 Received: from mail-pg1-f171.google.com (mail-pg1-f171.google.com [209.85.215.171]) by imf30.hostedemail.com (Postfix) with ESMTP id 24388800C5 for ; Tue, 17 May 2022 09:16:46 +0000 (UTC) Received: by mail-pg1-f171.google.com with SMTP id h24so11110256pgh.12 for ; Tue, 17 May 2022 02:17:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=E8YGWSWWojih1VKbtgTaPJ1Z6S4eE96LyrRQW+VNJuo=; b=JI/N/9lYrny+vGuuJmW/Mz1EwloPiEjhN5PZon9WeBaiDjglsT4Enu5a5xHVRZowOg 9f3A17ll9qIQChEyLVLsVampoZaCPeLaG4XBeilDJhXBWZbrmNaGpxkZOVLYFaQLD6yh /m2bw9s2rGOy5vAk+xOFwaw/t8tuyJV2+DyDH+XizMJ6Gm5RhK7wbA1qpyUv7p3SdWZr DHfk71IEAw0lPD8PMXyKfPLy8XSSFX2sAnqmA9/yObH9mgCAlICK9Y2fzSydlVHpzxhR 9KZFz/lLG0hIcoEFXrFxC6O06kxPgggx5ocXTGPVirYrnk1XPOE+jT9zbPorcmfYK9q2 2h3A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=E8YGWSWWojih1VKbtgTaPJ1Z6S4eE96LyrRQW+VNJuo=; b=KdPNpKS/B+Hsp/sK9r671AzqjTicJjIwuEwoVz7ktu1no521I3mtF4gSi4jfxLgO0Z B2wRhVFMKS6vKC5y6u5Gq2I9chWhFriIcMnqYhwzzVhFvoV3ewrz56Yo0Uz1iZ3NE7/w YOq5fSaSXtY9yViS2nSOOL2Thva8fXaVSXKun8M4JigaU9pTLh4rtfx6cBYZnqcHZXE1 kj0pSqYAyEpJJzaSIBova15pIzFghwoE9rFKmIpsI4xwDH7UtSkb5TUU381vPySIDhMn RCsnNyln8khWg4jvPlmCGzjuKwEimqbQ2CcAQxaXJkdtBaNUa9APHfekR/AnaWvzau1x Xwxg== X-Gm-Message-State: AOAM530nJ+/7fJUbS5Rv8Ok7uRHBVtm0q5Q+hDcWF5sa8gyhwy/XGhPx J8kDTo1DVAzdyp7ZYWW6f05X/wKVQW9axt0HCdA= X-Google-Smtp-Source: ABdhPJyQmaSFdo5O73mmcLowlQG4SBLDZevrKgfoPfruisJEss3MbayYyRyPbPsBJRt31o5gOkJvjo7bWF5VvtSyJEA= X-Received: by 2002:a05:6a00:244a:b0:4fa:ebf9:75de with SMTP id d10-20020a056a00244a00b004faebf975demr21562526pfj.73.1652779028918; Tue, 17 May 2022 02:17:08 -0700 (PDT) MIME-Version: 1.0 References: <20220517082650.2005840-1-hsinyi@chromium.org> <20220517082650.2005840-4-hsinyi@chromium.org> In-Reply-To: <20220517082650.2005840-4-hsinyi@chromium.org> From: Xiongwei Song Date: Tue, 17 May 2022 17:16:42 +0800 Message-ID: Subject: Re: [PATCH v2 3/3] squashfs: implement readahead To: Hsin-Yi Wang Cc: Phillip Lougher , Matthew Wilcox , Xiongwei Song , Zheng Liang , Zhang Yi , Hou Tao , Miao Xie , Andrew Morton , "linux-mm @ kvack . org" , "squashfs-devel @ lists . sourceforge . net" , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" X-Stat-Signature: jttbq3ci6wk7wyfc3u14hfzthfupirza X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 24388800C5 X-Rspam-User: Authentication-Results: imf30.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b="JI/N/9lY"; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (imf30.hostedemail.com: domain of sxwjean@gmail.com designates 209.85.215.171 as permitted sender) smtp.mailfrom=sxwjean@gmail.com X-HE-Tag: 1652779006-503349 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: On Tue, May 17, 2022 at 4:28 PM Hsin-Yi Wang wrote: > > Implement readahead callback for squashfs. It will read datablocks > which cover pages in readahead request. For a few cases it will > not mark page as uptodate, including: > - file end is 0. > - zero filled blocks. > - current batch of pages isn't in the same datablock or not enough in a > datablock. > Otherwise pages will be marked as uptodate. The unhandled pages will be > updated by readpage later. > > Suggested-by: Matthew Wilcox > Signed-off-by: Hsin-Yi Wang > Reported-by: Matthew Wilcox > Reported-by: Phillip Lougher > Reported-by: Xiongwei Song "xiongwei.song@windriver.com" too. > --- > v1->v2: remove unused check on readahead_expand(). > v1: https://lore.kernel.org/lkml/20220516105100.1412740-3-hsinyi@chromium.org/ > --- > fs/squashfs/file.c | 77 +++++++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 76 insertions(+), 1 deletion(-) > > diff --git a/fs/squashfs/file.c b/fs/squashfs/file.c > index a8e495d8eb86..e10a55c5b1eb 100644 > --- a/fs/squashfs/file.c > +++ b/fs/squashfs/file.c > @@ -39,6 +39,7 @@ > #include "squashfs_fs_sb.h" > #include "squashfs_fs_i.h" > #include "squashfs.h" > +#include "page_actor.h" > > /* > * Locate cache slot in range [offset, index] for specified inode. If > @@ -495,7 +496,81 @@ static int squashfs_read_folio(struct file *file, struct folio *folio) > return 0; > } > > +static void squashfs_readahead(struct readahead_control *ractl) > +{ > + struct inode *inode = ractl->mapping->host; > + struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info; > + size_t mask = (1UL << msblk->block_log) - 1; > + size_t shift = msblk->block_log - PAGE_SHIFT; > + loff_t start = readahead_pos(ractl) &~ mask; > + size_t len = readahead_length(ractl) + readahead_pos(ractl) - start; > + struct squashfs_page_actor *actor; > + unsigned int nr_pages = 0; > + struct page **pages; > + u64 block = 0; > + int bsize, res, i, index; > + int file_end = i_size_read(inode) >> msblk->block_log; > + unsigned int max_pages = 1UL << shift; > + > + readahead_expand(ractl, start, (len | mask) + 1); > + > + if (file_end == 0) > + return; > + > + pages = kmalloc_array(max_pages, sizeof(void *), GFP_KERNEL); > + if (!pages) > + return; > + > + actor = squashfs_page_actor_init_special(pages, max_pages, 0); > + if (!actor) > + goto out; > + > + for (;;) { > + nr_pages = __readahead_batch(ractl, pages, max_pages); > + if (!nr_pages) > + break; > + > + if (readahead_pos(ractl) >= i_size_read(inode) || > + nr_pages < max_pages) > + goto skip_pages; > + > + index = pages[0]->index >> shift; > + if ((pages[nr_pages - 1]->index >> shift) != index) > + goto skip_pages; > + > + bsize = read_blocklist(inode, index, &block); > + if (bsize == 0) > + goto skip_pages; > + > + res = squashfs_read_data(inode->i_sb, block, bsize, NULL, > + actor); > + > + if (res >= 0) > + for (i = 0; i < nr_pages; i++) > + SetPageUptodate(pages[i]); > + > + for (i = 0; i < nr_pages; i++) { > + unlock_page(pages[i]); > + put_page(pages[i]); > + } > + } > + > + kfree(actor); > + kfree(pages); > + return; > + > +skip_pages: > + for (i = 0; i < nr_pages; i++) { > + unlock_page(pages[i]); > + put_page(pages[i]); > + } > + > + kfree(actor); > +out: > + kfree(pages); > +} > > const struct address_space_operations squashfs_aops = { > - .read_folio = squashfs_read_folio > + .read_folio = squashfs_read_folio, > + .readahead = squashfs_readahead > }; > -- > 2.36.0.550.gb090851708-goog > >