diff options
author | Peter Zijlstra <a.p.zijlstra@chello.nl> | 2011-05-24 17:12:04 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-05-25 08:39:17 -0700 |
commit | 97a894136f29802da19a15541de3c019e1ca147e (patch) | |
tree | 1fd3f92ba92a37d5d8527a1f41458091d0a944dc /include/linux/mm.h | |
parent | e4c70a6629f9c74c4b0de258a3951890e9047c82 (diff) |
mm: Remove i_mmap_lock lockbreak
Hugh says:
"The only significant loser, I think, would be page reclaim (when
concurrent with truncation): could spin for a long time waiting for
the i_mmap_mutex it expects would soon be dropped? "
Counter points:
- cpu contention makes the spin stop (need_resched())
- zap pages should be freeing pages at a higher rate than reclaim
ever can
I think the simplification of the truncate code is definitely worth it.
Effectively reverts: 2aa15890f3c ("mm: prevent concurrent
unmap_mapping_range() on the same inode") and takes out the code that
caused its problem.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Miller <davem@davemloft.net>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux/mm.h')
-rw-r--r-- | include/linux/mm.h | 2 |
1 files changed, 0 insertions, 2 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index ffcce9bf2b54..2ad0ac8c3f32 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -895,8 +895,6 @@ struct zap_details { struct address_space *check_mapping; /* Check page->mapping if set */ pgoff_t first_index; /* Lowest page->index to unmap */ pgoff_t last_index; /* Highest page->index to unmap */ - spinlock_t *i_mmap_lock; /* For unmap_mapping_range: */ - unsigned long truncate_count; /* Compare vm_truncate_count */ }; struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr, |