diff options
| author | Ingo Molnar <mingo@kernel.org> | 2012-12-02 19:56:46 +0000 |
|---|---|---|
| committer | Mel Gorman <mgorman@suse.de> | 2012-12-11 14:43:00 +0000 |
| commit | 5a505085f043e8380f83610f79642853c051e2f1 (patch) | |
| tree | c9e86ee196b1ef87350ee9b268a515e2eae4d307 /include/linux/rmap.h | |
| parent | d28d433512f4f387e2563c14db45a7bb8a338b1a (diff) | |
mm/rmap: Convert the struct anon_vma::mutex to an rwsem
Convert the struct anon_vma::mutex to an rwsem, which will help
in solving a page-migration scalability problem. (Addressed in
a separate patch.)
The conversion is simple and straightforward: in every case
where we mutex_lock()ed we'll now down_write().
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Turner <pjt@google.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Diffstat (limited to 'include/linux/rmap.h')
| -rw-r--r-- | include/linux/rmap.h | 16 |
1 files changed, 8 insertions, 8 deletions
diff --git a/include/linux/rmap.h b/include/linux/rmap.h index bfe1f4780644..f3f41d242e25 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -7,7 +7,7 @@ #include <linux/list.h> #include <linux/slab.h> #include <linux/mm.h> -#include <linux/mutex.h> +#include <linux/rwsem.h> #include <linux/memcontrol.h> /* @@ -25,8 +25,8 @@ * pointing to this anon_vma once its vma list is empty. */ struct anon_vma { - struct anon_vma *root; /* Root of this anon_vma tree */ - struct mutex mutex; /* Serialize access to vma list */ + struct anon_vma *root; /* Root of this anon_vma tree */ + struct rw_semaphore rwsem; /* W: modification, R: walking the list */ /* * The refcount is taken on an anon_vma when there is no * guarantee that the vma of page tables will exist for @@ -64,7 +64,7 @@ struct anon_vma_chain { struct vm_area_struct *vma; struct anon_vma *anon_vma; struct list_head same_vma; /* locked by mmap_sem & page_table_lock */ - struct rb_node rb; /* locked by anon_vma->mutex */ + struct rb_node rb; /* locked by anon_vma->rwsem */ unsigned long rb_subtree_last; #ifdef CONFIG_DEBUG_VM_RB unsigned long cached_vma_start, cached_vma_last; @@ -108,24 +108,24 @@ static inline void vma_lock_anon_vma(struct vm_area_struct *vma) { struct anon_vma *anon_vma = vma->anon_vma; if (anon_vma) - mutex_lock(&anon_vma->root->mutex); + down_write(&anon_vma->root->rwsem); } static inline void vma_unlock_anon_vma(struct vm_area_struct *vma) { struct anon_vma *anon_vma = vma->anon_vma; if (anon_vma) - mutex_unlock(&anon_vma->root->mutex); + up_write(&anon_vma->root->rwsem); } static inline void anon_vma_lock(struct anon_vma *anon_vma) { - mutex_lock(&anon_vma->root->mutex); + down_write(&anon_vma->root->rwsem); } static inline void anon_vma_unlock(struct anon_vma *anon_vma) { - mutex_unlock(&anon_vma->root->mutex); + up_write(&anon_vma->root->rwsem); } /* |