From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.suse.de ([195.135.220.15]:38038 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727514AbeHaL7I (ORCPT ); Fri, 31 Aug 2018 07:59:08 -0400 Subject: Re: [PATCH 04/35] btrfs: only track ref_heads in delayed_ref_updates To: Josef Bacik , linux-btrfs@vger.kernel.org References: <20180830174225.2200-1-josef@toxicpanda.com> <20180830174225.2200-5-josef@toxicpanda.com> From: Nikolay Borisov Message-ID: <162a5b6e-d361-9385-c95b-afc8bc25563c@suse.com> Date: Fri, 31 Aug 2018 10:52:55 +0300 MIME-Version: 1.0 In-Reply-To: <20180830174225.2200-5-josef@toxicpanda.com> Content-Type: text/plain; charset=utf-8 Sender: linux-btrfs-owner@vger.kernel.org List-ID: On 30.08.2018 20:41, Josef Bacik wrote: > From: Josef Bacik > > We use this number to figure out how many delayed refs to run, but > __btrfs_run_delayed_refs really only checks every time we need a new > delayed ref head, so we always run at least one ref head completely no > matter what the number of items on it. So instead track only the ref > heads added by this trans handle and adjust the counting appropriately > in __btrfs_run_delayed_refs. > > Signed-off-by: Josef Bacik > --- > fs/btrfs/delayed-ref.c | 3 --- > fs/btrfs/extent-tree.c | 5 +---- > 2 files changed, 1 insertion(+), 7 deletions(-) > > diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c > index 3a9e4ac21794..27f7dd4e3d52 100644 > --- a/fs/btrfs/delayed-ref.c > +++ b/fs/btrfs/delayed-ref.c > @@ -234,8 +234,6 @@ static inline void drop_delayed_ref(struct btrfs_trans_handle *trans, > ref->in_tree = 0; > btrfs_put_delayed_ref(ref); > atomic_dec(&delayed_refs->num_entries); > - if (trans->delayed_ref_updates) > - trans->delayed_ref_updates--; There was feedback on this particular hunk and you've completely ignored it, that's not nice: https://www.spinics.net/lists/linux-btrfs/msg80514.html > } > > static bool merge_ref(struct btrfs_trans_handle *trans, > @@ -460,7 +458,6 @@ static int insert_delayed_ref(struct btrfs_trans_handle *trans, > if (ref->action == BTRFS_ADD_DELAYED_REF) > list_add_tail(&ref->add_list, &href->ref_add_list); > atomic_inc(&root->num_entries); > - trans->delayed_ref_updates++; > spin_unlock(&href->lock); > return ret; > } > diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c > index 87c42a2c45b1..20531389a20a 100644 > --- a/fs/btrfs/extent-tree.c > +++ b/fs/btrfs/extent-tree.c > @@ -2583,6 +2583,7 @@ static noinline int __btrfs_run_delayed_refs(struct btrfs_trans_handle *trans, > spin_unlock(&delayed_refs->lock); > break; > } > + count++; > > /* grab the lock that says we are going to process > * all the refs for this head */ > @@ -2596,7 +2597,6 @@ static noinline int __btrfs_run_delayed_refs(struct btrfs_trans_handle *trans, > */ > if (ret == -EAGAIN) { > locked_ref = NULL; > - count++; > continue; > } > } > @@ -2624,7 +2624,6 @@ static noinline int __btrfs_run_delayed_refs(struct btrfs_trans_handle *trans, > unselect_delayed_ref_head(delayed_refs, locked_ref); > locked_ref = NULL; > cond_resched(); > - count++; > continue; > } > > @@ -2642,7 +2641,6 @@ static noinline int __btrfs_run_delayed_refs(struct btrfs_trans_handle *trans, > return ret; > } > locked_ref = NULL; > - count++; > continue; > } > > @@ -2693,7 +2691,6 @@ static noinline int __btrfs_run_delayed_refs(struct btrfs_trans_handle *trans, > } > > btrfs_put_delayed_ref(ref); > - count++; > cond_resched(); > } > >