patches/kernel/0021-ocfs2-make-metadata-estimation-accurate-and-clear.patch

   1 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
   2 From: Changwei Ge <ge.changwei@h3c.com>
   3 Date: Wed, 31 Jan 2018 16:15:02 -0800
   4 Subject: [PATCH] ocfs2: make metadata estimation accurate and clear
   5 MIME-Version: 1.0
   6 Content-Type: text/plain; charset=UTF-8
   7 Content-Transfer-Encoding: 8bit
   8
   9 Current code assume that ::w_unwritten_list always has only one item on.
  10 This is not right and hard to get understood.  So improve how to count
  11 unwritten item.
  12
  13 Link: http://lkml.kernel.org/r/1515479070-32653-1-git-send-email-ge.changwei@h3c.com
  14 Signed-off-by: Changwei Ge <ge.changwei@h3c.com>
  15 Reported-by: John Lightsey <john@nixnuts.net>
  16 Tested-by: John Lightsey <john@nixnuts.net>
  17 Cc: Mark Fasheh <mfasheh@versity.com>
  18 Cc: Joseph Qi <jiangqi903@gmail.com>
  19 Cc: Junxiao Bi <junxiao.bi@oracle.com>
  20 Cc: Joel Becker <jlbec@evilplan.org>
  21 Cc: Changwei Ge <ge.changwei@h3c.com>
  22 Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
  23 Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
  24 (cherry picked from commit 63de8bd9328bf2a778fc277503da163ae3defa3c)
  25 Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
  26 ---
  27  fs/ocfs2/aops.c | 4 +++-
  28  1 file changed, 3 insertions(+), 1 deletion(-)
  29
  30 diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
  31 index 88a31e9340a0..77ec9b495027 100644
  32 --- a/fs/ocfs2/aops.c
  33 +++ b/fs/ocfs2/aops.c
  34 @@ -784,6 +784,7 @@ struct ocfs2_write_ctxt {
  35         struct ocfs2_cached_dealloc_ctxt w_dealloc;
  36
  37         struct list_head                w_unwritten_list;
  38 +       unsigned int                    w_unwritten_count;
  39  };
  40
  41  void ocfs2_unlock_and_free_pages(struct page **pages, int num_pages)
  42 @@ -1373,6 +1374,7 @@ static int ocfs2_unwritten_check(struct inode *inode,
  43         desc->c_clear_unwritten = 0;
  44         list_add_tail(&new->ue_ip_node, &oi->ip_unwritten_list);
  45         list_add_tail(&new->ue_node, &wc->w_unwritten_list);
  46 +       wc->w_unwritten_count++;
  47         new = NULL;
  48  unlock:
  49         spin_unlock(&oi->ip_lock);
  50 @@ -2246,7 +2248,7 @@ static int ocfs2_dio_get_block(struct inode *inode, sector_t iblock,
  51                 ue->ue_phys = desc->c_phys;
  52
  53                 list_splice_tail_init(&wc->w_unwritten_list, &dwc->dw_zero_list);
  54 -               dwc->dw_zero_count++;
  55 +               dwc->dw_zero_count += wc->w_unwritten_count;
  56         }
  57
  58         ret = ocfs2_write_end_nolock(inode->i_mapping, pos, len, len, wc);