From patchwork Fri May 11 20:13:36 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Omar Sandoval X-Patchwork-Id: 10395305 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 113BE601A0 for ; Fri, 11 May 2018 20:14:08 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 057C328D2D for ; Fri, 11 May 2018 20:14:08 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id ECD5928FB6; Fri, 11 May 2018 20:14:07 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI, T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B9B0728D2D for ; Fri, 11 May 2018 20:14:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751943AbeEKUOE (ORCPT ); Fri, 11 May 2018 16:14:04 -0400 Received: from mail-pf0-f195.google.com ([209.85.192.195]:33969 "EHLO mail-pf0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751764AbeEKUN7 (ORCPT ); Fri, 11 May 2018 16:13:59 -0400 Received: by mail-pf0-f195.google.com with SMTP id a14-v6so3213074pfi.1 for ; Fri, 11 May 2018 13:13:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=osandov-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :in-reply-to:references; bh=pTK4n0EAJ5E5q1HshbvmMBBIo/1Z6xnPXWv45NeFQrA=; b=udna+pTVhmLLYhbNjPOsatIMKG1+TOpM7AY+ssIqbL5dyjAH+W41yKy600lKcVhPgv +qpMcJt4BUZfSa9RiSQKEDSjvPmHDP1yPSCpV+GNaDeN5bINwNjwQ6zoI5k2dQts+nXC kfknA+cQnOEvkU7A7Lylij+WolJZ0d4fh6iR69YKAFaEMYTeey++N785f+7j9OjyZvVA 9y7+B41FbQvmH0OCImDfnuFgF4dOn0Y80ob4MfVP1+72/9OKt3F9sDtuuNLZD6lc540P a6lHUVKnwSmYeIcfJqjZXtXjuCHU+XVxXK0eERkxXrQpKIce7MPNQYgQkhOetRNxt7eA LB0g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:in-reply-to:references; bh=pTK4n0EAJ5E5q1HshbvmMBBIo/1Z6xnPXWv45NeFQrA=; b=Mg/DHHJ8QAozx5KdpkC/+s7QVTZ0Zm3fdorSFCxPqQRAy3uH243oA44Lvjyn7yE8OZ QG1FX11Q28z7+vwL5fnyjCjeJNsdElXlrOi4NidcwFEeP85URme0QARJwf3m5jW6paU/ e+7EJcFrAOGlnWnNRj5OcF6hpGDSTt7Ii6uVzsFK+hKLwn6IZsY//N335rwTf5h2sHbd 9q+e3vroSxVB/4zFKJtHX+7RX+oTKSA8Tklpy8CADbbjMFpK/AW8spltjX+uIc9YHhxh p1ZlcjT3RNiiRiZGE8/dboMdAk0FFz3hnNFXhR1M0Xp9jTJglqm/ZrqmDa0vy7PsmKbm 5Xcg== X-Gm-Message-State: ALKqPwfgWK/2sJNgIipCNJJ/HghACNoEt2hJvEUrZxwM0D9iC70Z/SOs YTH7LVzJndGWDtDCDLfj3sEE6Nv27xY= X-Google-Smtp-Source: AB8JxZqY8O8oY+4aN5l6ghNibA+Xl29bzxtPcPWPHx/GOzB76kTX7YkA4DA69N/VF0cgciI5BE2fLw== X-Received: by 2002:a65:5787:: with SMTP id b7-v6mr391080pgr.130.1526069638927; Fri, 11 May 2018 13:13:58 -0700 (PDT) Received: from vader.thefacebook.com ([2620:10d:c090:200::7:51e4]) by smtp.gmail.com with ESMTPSA id x84-v6sm10088457pfi.160.2018.05.11.13.13.57 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 11 May 2018 13:13:58 -0700 (PDT) From: Omar Sandoval To: linux-btrfs@vger.kernel.org Cc: kernel-team@fb.com, Chris Mason , Josef Bacik , Nikolay Borisov , David Sterba Subject: [PATCH v4 08/12] Btrfs: refactor btrfs_evict_inode() reserve refill dance Date: Fri, 11 May 2018 13:13:36 -0700 Message-Id: X-Mailer: git-send-email 2.17.0 In-Reply-To: References: In-Reply-To: References: Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Omar Sandoval The truncate loop in btrfs_evict_inode() does two things at once: - It refills the temporary block reserve, potentially stealing from the global reserve or committing - It calls btrfs_truncate_inode_items() The tangle of continues hides the fact that these two steps are actually separate. Split the first step out into a separate function both for clarity and so that we can reuse it in a later patch. Reviewed-by: Nikolay Borisov Signed-off-by: Omar Sandoval --- fs/btrfs/inode.c | 113 ++++++++++++++++++----------------------------- 1 file changed, 42 insertions(+), 71 deletions(-) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index ad4b7fb62f46..0a753f3a3321 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -5189,13 +5189,52 @@ static void evict_inode_truncate_pages(struct inode *inode) spin_unlock(&io_tree->lock); } +static struct btrfs_trans_handle *evict_refill_and_join(struct btrfs_root *root, + struct btrfs_block_rsv *rsv, + u64 min_size) +{ + struct btrfs_fs_info *fs_info = root->fs_info; + struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv; + int failures = 0; + + for (;;) { + struct btrfs_trans_handle *trans; + int ret; + + ret = btrfs_block_rsv_refill(root, rsv, min_size, + BTRFS_RESERVE_FLUSH_LIMIT); + + if (ret && ++failures > 2) { + btrfs_warn(fs_info, + "could not allocate space for a delete; will truncate on mount"); + return ERR_PTR(-ENOSPC); + } + + trans = btrfs_join_transaction(root); + if (IS_ERR(trans) || !ret) + return trans; + + /* + * Try to steal from the global reserve if there is space for + * it. + */ + if (!btrfs_check_space_for_delayed_refs(trans, fs_info) && + !btrfs_block_rsv_migrate(global_rsv, rsv, min_size, 0)) + return trans; + + /* If not, commit and try again. */ + ret = btrfs_commit_transaction(trans); + if (ret) + return ERR_PTR(ret); + } +} + void btrfs_evict_inode(struct inode *inode) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); struct btrfs_trans_handle *trans; struct btrfs_root *root = BTRFS_I(inode)->root; - struct btrfs_block_rsv *rsv, *global_rsv; - int steal_from_global = 0; + struct btrfs_block_rsv *rsv; u64 min_size; int ret; @@ -5248,85 +5287,17 @@ void btrfs_evict_inode(struct inode *inode) } rsv->size = min_size; rsv->failfast = 1; - global_rsv = &fs_info->global_block_rsv; btrfs_i_size_write(BTRFS_I(inode), 0); - /* - * This is a bit simpler than btrfs_truncate since we've already - * reserved our space for our orphan item in the unlink, so we just - * need to reserve some slack space in case we add bytes and update - * inode item when doing the truncate. - */ while (1) { - ret = btrfs_block_rsv_refill(root, rsv, min_size, - BTRFS_RESERVE_FLUSH_LIMIT); - - /* - * Try and steal from the global reserve since we will - * likely not use this space anyway, we want to try as - * hard as possible to get this to work. - */ - if (ret) - steal_from_global++; - else - steal_from_global = 0; - ret = 0; - - /* - * steal_from_global == 0: we reserved stuff, hooray! - * steal_from_global == 1: we didn't reserve stuff, boo! - * steal_from_global == 2: we've committed, still not a lot of - * room but maybe we'll have room in the global reserve this - * time. - * steal_from_global == 3: abandon all hope! - */ - if (steal_from_global > 2) { - btrfs_warn(fs_info, - "Could not get space for a delete, will truncate on mount %d", - ret); - btrfs_orphan_del(NULL, BTRFS_I(inode)); - btrfs_free_block_rsv(fs_info, rsv); - goto no_delete; - } - - trans = btrfs_join_transaction(root); + trans = evict_refill_and_join(root, rsv, min_size); if (IS_ERR(trans)) { btrfs_orphan_del(NULL, BTRFS_I(inode)); btrfs_free_block_rsv(fs_info, rsv); goto no_delete; } - /* - * We can't just steal from the global reserve, we need to make - * sure there is room to do it, if not we need to commit and try - * again. - */ - if (steal_from_global) { - if (!btrfs_check_space_for_delayed_refs(trans, fs_info)) - ret = btrfs_block_rsv_migrate(global_rsv, rsv, - min_size, 0); - else - ret = -ENOSPC; - } - - /* - * Couldn't steal from the global reserve, we have too much - * pending stuff built up, commit the transaction and try it - * again. - */ - if (ret) { - ret = btrfs_commit_transaction(trans); - if (ret) { - btrfs_orphan_del(NULL, BTRFS_I(inode)); - btrfs_free_block_rsv(fs_info, rsv); - goto no_delete; - } - continue; - } else { - steal_from_global = 0; - } - trans->block_rsv = rsv; ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0);