1. 27 2月, 2011 9 次提交
    • T
      ext4: move setup of the mpd structure to write_cache_pages_da() · 168fc022
      Theodore Ts'o 提交于
      Move the initialization of all of the fields of the mpd structure to
      write_cache_pages_da().  This simplifies the code considerably.
      Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      168fc022
    • T
      ext4: don't lock the next page in write_cache_pages if not needed · 78aaced3
      Theodore Ts'o 提交于
      If we have accumulated a contiguous region of memory to be written
      out, and the next page can added to this region, don't bother locking
      (and then unlocking the page) before writing out the memory.  In the
      unlikely event that the next page was being written back by some other
      CPU, we can also skip waiting that page to finish writeback.
      Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      78aaced3
    • T
      ext4: remove page_skipped hackery in ext4_da_writepages() · ee6ecbcc
      Theodore Ts'o 提交于
      Because the ext4 page writeback codepath had been prematurely calling
      clear_page_dirty_for_io(), if it turned out that a particular page
      couldn't be written out during a particular pass of
      write_cache_pages_da(), the page would have to get redirtied by
      calling redirty_pages_for_writeback().  Not only was this wasted work,
      but redirty_page_for_writeback() would increment wbc->pages_skipped to
      signal to writeback_sb_inodes() that buffers were locked, and that it
      should skip this inode until later.
      
      Since this signal was incorrect in ext4's case --- which was caused by
      ext4's historically incorrect use of write_cache_pages() ---
      ext4_da_writepages() saved and restored wbc->skipped_pages to avoid
      confusing writeback_sb_inodes().
      
      Now that we've fixed ext4 to call clear_page_dirty_for_io() right
      before initiating the page I/O, we can nuke the page_skipped
      save/restore hackery, and breathe a sigh of relief.
      Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      ee6ecbcc
    • T
      ext4: clear the dirty bit for a page in writeback at the last minute · 97498956
      Theodore Ts'o 提交于
      Move when we call clear_page_dirty_for_io() to just before we actually
      write the page.  This simplifies the code somewhat, and avoids marking
      pages as clean and then needing to remark them as dirty later.
      Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      97498956
    • T
      ext4: simple cleanups to write_cache_pages_da() · 4f01b02c
      Theodore Ts'o 提交于
      Eliminate duplicate code, unneeded variables, etc., to make it easier
      to understand the code.  No behavioral changes were made in this patch.
      Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      4f01b02c
    • T
      ext4: fold __mpage_da_writepage() into write_cache_pages_da() · 8eb9e5ce
      Theodore Ts'o 提交于
      Fold the __mpage_da_writepage() function into write_cache_pages_da().
      This will give us opportunities to clean up and simplify the resulting
      code.
      Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      8eb9e5ce
    • T
      ext4: enable mblk_io_submit by default · 6fd7a467
      Theodore Ts'o 提交于
      Now that we've fixed the file corruption bug in commit d50bdd5a,
      it's time to enable mblk_io_submit by default.
      Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      6fd7a467
    • C
      ext4: fix ext4_da_block_invalidatepages() to handle page range properly · c7f5938a
      Curt Wohlgemuth 提交于
      If ext4_da_block_invalidatepages() is called because of a
      failure from ext4_map_blocks() in mpage_da_map_and_submit(),
      it's supposed to clean up -- including unlock -- all the
      pages in the mpd structure.  But these values may not match
      up, even on a system in which block size == page size:
      
         mpd->b_blocknr != mpd->first_page
         mpd->b_size != (mpd->next_page - mpd->first_page)
      
      ext4_da_block_invalidatepages() has been using b_blocknr and
      b_size; this patch changes it to use first_page and
      next_page.
      
      Tested:  I injected a small number (5%) of failures in
      ext4_map_blocks() in the case that the flags contain
      EXT4_GET_BLOCKS_DELALLOC_RESERVE, and ran fsstress on this
      kernel.  Without this patch, I got hung tasks every time.
      With this patch, I see no hangs in many runs of fsstress.
      Signed-off-by: NCurt Wohlgemuth <curtw@google.com>
      Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      c7f5938a
    • C
      ext4: mark multi-page IO complete on mapping failure · e0fd9b90
      Curt Wohlgemuth 提交于
      In mpage_da_map_and_submit(), if we have a delayed block
      allocation failure from ext4_map_blocks(), we need to mark
      the IO as complete, by setting
      
            mpd->io_done = 1;
      
      Otherwise, we could end up submitting the pages in an outer
      loop; since they are unlocked on mapping failure in
      ext4_da_block_invalidatepages(), this will cause a bug check
      in mpage_da_submit_io().
      
      I tested this by injected failures into ext4_map_blocks().
      Without this patch, a simple fsstress run will bug check;
      with the patch, it works fine.
      Signed-off-by: NCurt Wohlgemuth <curtw@google.com>
      Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      e0fd9b90
  2. 25 2月, 2011 5 次提交
    • C
      ext4: mballoc: don't replace the current preallocation group unnecessarily · 5a54b2f1
      Coly Li 提交于
      In ext4_mb_check_group_pa(), the current preallocation space is
      replaced with a new preallocation space when the two have the same
      distance from the goal block.
      
      This doesn't actually gain us anything, so change things so that the
      function only switches to the new preallocation group if its distance
      from the goal block is strictly smaller than the current preallocaiton
      group's distance from the goal block.
      Signed-off-by: NColy Li <bosong.ly@taobao.com>
      Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      5a54b2f1
    • C
      ext4: clarify description of ac_g_ex in struct ext4_allocation_context · 58696f3a
      Coly Li 提交于
      Signed-off-by: NColy Li <bosong.ly@taobao.com>
      Cc: Alex Tomas <alex@clusterfs.com>
      Cc: Theodore Tso <tytso@google.com>
      58696f3a
    • C
      mballoc: add comments to ext4_mb_mark_free_simple() · 7c786059
      Coly Li 提交于
      This patch adds comments to ext4_mb_mark_free_simple to make it more
      understandable.
      Signed-off-by: NColy Li <bosong.ly@taobao.com>
      Cc: Alex Tomas <alex@clusterfs.com>
      Cc: Theodore Tso <tytso@google.com>
      7c786059
    • C
      ext4: remove unncessary call mb_find_buddy() in debugging code · 235772da
      Coly Li 提交于
      In __mb_check_buddy(), look at the code below:
        591         fstart = -1;
        592         buddy = mb_find_buddy(e4b, 0, &max);
        593         for (i = 0; i < max; i++) {
        594                 if (!mb_test_bit(i, buddy)) {
        595                         MB_CHECK_ASSERT(i >= e4b->bd_info->bb_first_free);
        596                         if (fstart == -1) {
        597                                 fragments++;
        598                                 fstart = i;
        599                         }
        600                         continue;
        601                 }
        602                 fstart = -1;
        603                 /* check used bits only */
        604                 for (j = 0; j < e4b->bd_blkbits + 1; j++) {
        605                         buddy2 = mb_find_buddy(e4b, j, &max2);
        606                         k = i >> j;
        607                         MB_CHECK_ASSERT(k < max2);
        608                         MB_CHECK_ASSERT(mb_test_bit(k, buddy2));
        609                 }
        610         }
        611         MB_CHECK_ASSERT(!EXT4_MB_GRP_NEED_INIT(e4b->bd_info));
        612         MB_CHECK_ASSERT(e4b->bd_info->bb_fragments == fragments);
        613
        614         grp = ext4_get_group_info(sb, e4b->bd_group);
        615         buddy = mb_find_buddy(e4b, 0, &max);
      
      On line 592, buddy is fetched by mb_find_buddy() with order 0, between
      line 593 to line 615, buddy is not changed, therefore there is
      no need to fetch buddy again from mb_find_buddy() with order 0 again.
      
      We can safely remove the second mb_find_buddy() on line 615.
      Signed-off-by: NColy Li <bosong.ly@taobao.com>
      Cc: Alex Tomas <alex@clusterfs.com>
      Cc: Theodore Tso <tytso@google.com>
      235772da
    • C
      ext4: code cleanup in mb_find_buddy() · 84b775a3
      Coly Li 提交于
      Current code calculate max no matter whether order is zero, it's
      unnecessary. This cleanup patch sets max to "1 << (e4b->bd_blkbits
      + 3)" only when order == 0.
      Signed-off-by: NColy Li <bosong.ly@taobao.com>
      Cc: Alex Tomas <alex@clusterfs.com>
      Cc: Theodore Tso <tytso@google.com>
      84b775a3
  3. 24 2月, 2011 4 次提交
  4. 22 2月, 2011 4 次提交
  5. 17 2月, 2011 1 次提交
    • L
      vfs: fix BUG_ON() in fs/namei.c:1461 · 3abb17e8
      Linus Torvalds 提交于
      When Al moved the nameidata_dentry_drop_rcu_maybe() call into the
      do_follow_link function in commit 844a3917 ("nothing in
      do_follow_link() is going to see RCU"), he mistakenly left the
      
      	BUG_ON(inode != path->dentry->d_inode);
      
      behind.  Which would otherwise be ok, but that BUG_ON() really needs to
      be _after_ dropping RCU, since the dentry isn't necessarily stable
      otherwise.
      
      So complete the code movement in that commit, and move the BUG_ON() into
      do_follow_link() too.  This means that we need to pass in 'inode' as an
      argument (just for this one use), but that's a small thing.  And
      eventually we may be confident enough in our path lookup that we can
      just remove the BUG_ON() and the unnecessary inode argument.
      Reported-and-tested-by: NEric Dumazet <eric.dumazet@gmail.com>
      Acked-by: NAl Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      3abb17e8
  6. 16 2月, 2011 17 次提交