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 2EBD2C4332F for ; Sat, 8 Jan 2022 06:05:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231701AbiAHGFc (ORCPT ); Sat, 8 Jan 2022 01:05:32 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55714 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229913AbiAHGFc (ORCPT ); Sat, 8 Jan 2022 01:05:32 -0500 Received: from mail-ed1-x533.google.com (mail-ed1-x533.google.com [IPv6:2a00:1450:4864:20::533]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EE25DC061574; Fri, 7 Jan 2022 22:05:31 -0800 (PST) Received: by mail-ed1-x533.google.com with SMTP id j6so30206922edw.12; Fri, 07 Jan 2022 22:05:31 -0800 (PST) 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=qKy0Ld0t/rb55huiDujNkhyOqnsFdqUh2fOUZOkxN48=; b=ElRDvdPLDhCghbXgOzk6lq0DvtAMSlweI65lMQ4TxnkMwgDT8qVmAz8Gz1ZcwPiXDZ OgGx76dYF5k5etnZL964lEtp0RFYI+0bSL1U8JsSbJIUYJxofeYy0nmAFWSft836JsBs EYZcEMpcjzeqSSS64G3L7mCdso3rRvofOOgCbUTCOxsjMUR8G4sEXSL9uOB26uqccwgP 8dShbjYVR8iMnvgsUFiDkyDltok/kMDA/wR/+txPjih1D1HcLpk0DIp3xSEAcCwkRLpl xGZdAF8BF3HZ0eR2h6xUQCl5j3g60VsSVEu8WQRJ9DYffDDFAIANaGD8BkaOH9r7wXQ4 cfKg== 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=qKy0Ld0t/rb55huiDujNkhyOqnsFdqUh2fOUZOkxN48=; b=XUit0u0q8Ml4Vaz5ETtCWJaiFvSHXh5ISlmJpNYcZcrqWX7FB1z0EuyNUqaeyvLg32 rKFW6MrPiR3G0LqR1jLJomk2kGFBroCcIvIQuPEk0V0KBysohGxTGpGnvbySSwgzyqrJ +8d1kPrcytCKevNZ6/5S7q8ZCm/tdguGeEt0QKBeKH+K5PowmT8fWirYfNUt5pHb76M3 wnimifkUR7rqJimOFXouUXhV57TD+gDmOTBhDGo3nXk847fEat/3ICRjA17GTmomzlcL eZeupIOxc+VeTK37m2iH1PC7x6GZSRCNj8Ga6aN3H3zR8B9iHYkZ/J74rGe9pY2X4kfG 6Pqw== X-Gm-Message-State: AOAM533xcqFEThay9o7EOSCNRLEYBi+yxQMzwoyCq2g4IPYdu8rDawZk 9p/wmAASH2iC10JW1Y03wWeRs19uaQhCa9s8tLw= X-Google-Smtp-Source: ABdhPJy2T/2xdEWvLdKJc3r4bh7gu318iPxRp81+gvESMiy7CEHxte4tHO54XPF/7TWqoNokTRo6zMZTBaLG4Jw2l60= X-Received: by 2002:a05:6402:4241:: with SMTP id g1mr65579080edb.11.1641621930273; Fri, 07 Jan 2022 22:05:30 -0800 (PST) MIME-Version: 1.0 References: <20220106024518.8161-1-yinxin.x@bytedance.com> <20220106024518.8161-2-yinxin.x@bytedance.com> In-Reply-To: From: harshad shirwadkar Date: Fri, 7 Jan 2022 22:05:19 -0800 Message-ID: Subject: Re: [External] Re: [PATCH 1/2] ext4: prevent used blocks from being allocated during fast commit replay To: Xin Yin Cc: "Theodore Y. Ts'o" , Andreas Dilger , Ext4 Developers List , linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org Ah, I see okay. Yeah, that makes sense. We do need to update fc_regions_valid for every addition during the replay phase. I think it may be helpful to add some comments describing this behavior in the code. But other than that, I think what you're doing is fine. Reviewed-by: Harshad Shirwadkar On Fri, Jan 7, 2022 at 6:09 PM Xin Yin wrote: > > On Sat, Jan 8, 2022 at 4:26 AM harshad shirwadkar > wrote: > > > > On Wed, Jan 5, 2022 at 6:45 PM Xin Yin wrote: > > > > > > during fast commit replay procedure, we clear inode blocks bitmap in > > > ext4_ext_clear_bb(), this may cause ext4_mb_new_blocks_simple() allocate > > > blocks still in use. > > > > > > make ext4_fc_record_regions() also record physical disk regions used by > > > inodes during replay procedure. Then ext4_mb_new_blocks_simple() can > > > excludes these blocks in use. > > > > > > Signed-off-by: Xin Yin > > > --- > > > fs/ext4/ext4.h | 2 ++ > > > fs/ext4/extents.c | 4 ++++ > > > fs/ext4/fast_commit.c | 11 ++++++++--- > > > 3 files changed, 14 insertions(+), 3 deletions(-) > > > > > > diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h > > > index 82fa51d6f145..7b0686758691 100644 > > > --- a/fs/ext4/ext4.h > > > +++ b/fs/ext4/ext4.h > > > @@ -2932,6 +2932,8 @@ bool ext4_fc_replay_check_excluded(struct super_block *sb, ext4_fsblk_t block); > > > void ext4_fc_replay_cleanup(struct super_block *sb); > > > int ext4_fc_commit(journal_t *journal, tid_t commit_tid); > > > int __init ext4_fc_init_dentry_cache(void); > > > +int ext4_fc_record_regions(struct super_block *sb, int ino, > > > + ext4_lblk_t lblk, ext4_fsblk_t pblk, int len, int replay); > > > > > > /* mballoc.c */ > > > extern const struct seq_operations ext4_mb_seq_groups_ops; > > > diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c > > > index c3e76a5de661..9b6c76629c93 100644 > > > --- a/fs/ext4/extents.c > > > +++ b/fs/ext4/extents.c > > > @@ -6096,11 +6096,15 @@ int ext4_ext_clear_bb(struct inode *inode) > > > > > > ext4_mb_mark_bb(inode->i_sb, > > > path[j].p_block, 1, 0); > > > + ext4_fc_record_regions(inode->i_sb, inode->i_ino, > > > + 0, path[j].p_block, 1, 1); > > > } > > > ext4_ext_drop_refs(path); > > > kfree(path); > > > } > > > ext4_mb_mark_bb(inode->i_sb, map.m_pblk, map.m_len, 0); > > > + ext4_fc_record_regions(inode->i_sb, inode->i_ino, > > > + map.m_lblk, map.m_pblk, map.m_len, 1); > > > } > > > cur = cur + map.m_len; > > > } > > > diff --git a/fs/ext4/fast_commit.c b/fs/ext4/fast_commit.c > > > index 23d13983a281..f0cd20f5fe5e 100644 > > > --- a/fs/ext4/fast_commit.c > > > +++ b/fs/ext4/fast_commit.c > > > @@ -1567,13 +1567,15 @@ static int ext4_fc_replay_create(struct super_block *sb, struct ext4_fc_tl *tl, > > > * Record physical disk regions which are in use as per fast commit area. Our > > > * simple replay phase allocator excludes these regions from allocation. > > > */ > > > -static int ext4_fc_record_regions(struct super_block *sb, int ino, > > > - ext4_lblk_t lblk, ext4_fsblk_t pblk, int len) > > > +int ext4_fc_record_regions(struct super_block *sb, int ino, > > > + ext4_lblk_t lblk, ext4_fsblk_t pblk, int len, int replay) > > Can you explain a bit why this replay parameter is needed here? This > > function simply reallocs the regions array if it doesn't have enough > > space. I am not sure why we need to change that behavior. > > ext4_fc_record_regions() originally only used during scan phase, and > set fc_regions_valid = fc_regions_use when getting a TAIL tag. Now we > also use it during the replay phase, and need to update > fc_regions_valid in this case, because ext4_fc_replay_check_excluded() > uses fc_regions_valid for regions checking. > Please correct me if I'm wrong. > > > > { > > > struct ext4_fc_replay_state *state; > > > struct ext4_fc_alloc_region *region; > > > > > > state = &EXT4_SB(sb)->s_fc_replay_state; > > > + if (replay && state->fc_regions_used != state->fc_regions_valid) > > > + state->fc_regions_used = state->fc_regions_valid; > > > if (state->fc_regions_used == state->fc_regions_size) { > > > state->fc_regions_size += > > > EXT4_FC_REPLAY_REALLOC_INCREMENT; > > > @@ -1591,6 +1593,9 @@ static int ext4_fc_record_regions(struct super_block *sb, int ino, > > > region->pblk = pblk; > > > region->len = len; > > > > > > + if (replay) > > > + state->fc_regions_valid++; > > > + > > > return 0; > > > } > > > > > > @@ -1938,7 +1943,7 @@ static int ext4_fc_replay_scan(journal_t *journal, > > > ret = ext4_fc_record_regions(sb, > > > le32_to_cpu(ext.fc_ino), > > > le32_to_cpu(ex->ee_block), ext4_ext_pblock(ex), > > > - ext4_ext_get_actual_len(ex)); > > > + ext4_ext_get_actual_len(ex), 0); > > > if (ret < 0) > > > break; > > > ret = JBD2_FC_REPLAY_CONTINUE; > > > -- > > > 2.20.1 > > >