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 8C98FC433FE for ; Thu, 29 Sep 2022 11:32:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235294AbiI2LcH (ORCPT ); Thu, 29 Sep 2022 07:32:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47726 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231340AbiI2LcE (ORCPT ); Thu, 29 Sep 2022 07:32:04 -0400 Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.220.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4F7D81432AF; Thu, 29 Sep 2022 04:32:03 -0700 (PDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id D447621C08; Thu, 29 Sep 2022 11:32:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1664451121; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=jeGyVzxEPfCc3Ba6i0mzqGwb3fxnvxrlnA7gUpxqvlE=; b=MnQn5C1fuvzrzKKTEyLL0eltGlUXjNy+RtBzsis8lMZsfBgnYKwhM0jnAfA16CDAxCkHid nXCxJRbCIe0QTpu+9GKGev8fe71FmxIYb0eAcM8q9gY+TPpQ4LGt/GbaesOvNxP1rGd9hN 5weYlHb6jMfHRMRO10mAcU/72bFgRJo= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1664451121; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=jeGyVzxEPfCc3Ba6i0mzqGwb3fxnvxrlnA7gUpxqvlE=; b=3/J8ojuXmWeDuCancxCdwkBH745Wgt9vLLjio8YMLp2QOo2M4LkVFEnCAgU08zzCg37V3b hDzkiyZ2TNhZpnBw== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id C57DF1348E; Thu, 29 Sep 2022 11:32:01 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id Vvg0MDGCNWNrcAAAMHmgww (envelope-from ); Thu, 29 Sep 2022 11:32:01 +0000 Received: by quack3.suse.cz (Postfix, from userid 1000) id 39211A0681; Thu, 29 Sep 2022 13:32:01 +0200 (CEST) Date: Thu, 29 Sep 2022 13:32:01 +0200 From: Jan Kara To: Ojaswin Mujoo Cc: linux-ext4@vger.kernel.org, Theodore Ts'o , Ritesh Harjani , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Andreas Dilger , Jan Kara , rookxu , Ritesh Harjani Subject: Re: [RFC v3 4/8] ext4: Move overlap assert logic into a separate function Message-ID: <20220929113201.2fbwzw2c7vecnduc@quack3> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue 27-09-22 14:46:44, Ojaswin Mujoo wrote: > Abstract out the logic to double check for overlaps in normalize_pa to > a separate function. Since there has been no reports in past where we > have seen any overlaps which hits this bug_on(), in future we can > consider calling this function under "#ifdef AGGRESSIVE_CHECK" only. > > There are no functional changes in this patch > > Signed-off-by: Ojaswin Mujoo > Reviewed-by: Ritesh Harjani (IBM) Looks good. Feel free to add: Reviewed-by: Jan Kara And I agree it might be interesting to move this code under appropriate ifdef. Honza > --- > fs/ext4/mballoc.c | 36 ++++++++++++++++++++++++------------ > 1 file changed, 24 insertions(+), 12 deletions(-) > > diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c > index 84950df709bb..d1ce34888dcc 100644 > --- a/fs/ext4/mballoc.c > +++ b/fs/ext4/mballoc.c > @@ -3985,6 +3985,29 @@ static void ext4_mb_normalize_group_request(struct ext4_allocation_context *ac) > mb_debug(sb, "goal %u blocks for locality group\n", ac->ac_g_ex.fe_len); > } > > +static inline void > +ext4_mb_pa_assert_overlap(struct ext4_allocation_context *ac, > + ext4_lblk_t start, ext4_lblk_t end) > +{ > + struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb); > + struct ext4_inode_info *ei = EXT4_I(ac->ac_inode); > + struct ext4_prealloc_space *tmp_pa; > + ext4_lblk_t tmp_pa_start, tmp_pa_end; > + > + rcu_read_lock(); > + list_for_each_entry_rcu(tmp_pa, &ei->i_prealloc_list, pa_inode_list) { > + spin_lock(&tmp_pa->pa_lock); > + if (tmp_pa->pa_deleted == 0) { > + tmp_pa_start = tmp_pa->pa_lstart; > + tmp_pa_end = tmp_pa->pa_lstart + EXT4_C2B(sbi, tmp_pa->pa_len); > + > + BUG_ON(!(start >= tmp_pa_end || end <= tmp_pa_start)); > + } > + spin_unlock(&tmp_pa->pa_lock); > + } > + rcu_read_unlock(); > +} > + > /* > * Normalization means making request better in terms of > * size and alignment > @@ -4141,18 +4164,7 @@ ext4_mb_normalize_request(struct ext4_allocation_context *ac, > size = end - start; > > /* XXX: extra loop to check we really don't overlap preallocations */ > - rcu_read_lock(); > - list_for_each_entry_rcu(tmp_pa, &ei->i_prealloc_list, pa_inode_list) { > - spin_lock(&tmp_pa->pa_lock); > - if (tmp_pa->pa_deleted == 0) { > - tmp_pa_start = tmp_pa->pa_lstart; > - tmp_pa_end = tmp_pa->pa_lstart + EXT4_C2B(sbi, tmp_pa->pa_len); > - > - BUG_ON(!(start >= tmp_pa_end || end <= tmp_pa_start)); > - } > - spin_unlock(&tmp_pa->pa_lock); > - } > - rcu_read_unlock(); > + ext4_mb_pa_assert_overlap(ac, start, end); > > /* > * In this function "start" and "size" are normalized for better > -- > 2.31.1 > -- Jan Kara SUSE Labs, CR