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authorLinus Torvalds <torvalds@linux-foundation.org>2012-12-17 02:33:25 +0400
committerLinus Torvalds <torvalds@linux-foundation.org>2012-12-17 03:18:08 +0400
commit3d59eebc5e137bd89c6351e4c70e90ba1d0dc234 (patch)
treeb4ddfd0b057454a7437a3b4e3074a3b8b4b03817 /mm/rmap.c
parent11520e5e7c1855fc3bf202bb3be35a39d9efa034 (diff)
parent4fc3f1d66b1ef0d7b8dc11f4ff1cc510f78b37d6 (diff)
downloadlinux-3d59eebc5e137bd89c6351e4c70e90ba1d0dc234.tar.xz
Merge tag 'balancenuma-v11' of git://git.kernel.org/pub/scm/linux/kernel/git/mel/linux-balancenuma
Pull Automatic NUMA Balancing bare-bones from Mel Gorman: "There are three implementations for NUMA balancing, this tree (balancenuma), numacore which has been developed in tip/master and autonuma which is in aa.git. In almost all respects balancenuma is the dumbest of the three because its main impact is on the VM side with no attempt to be smart about scheduling. In the interest of getting the ball rolling, it would be desirable to see this much merged for 3.8 with the view to building scheduler smarts on top and adapting the VM where required for 3.9. The most recent set of comparisons available from different people are mel: https://lkml.org/lkml/2012/12/9/108 mingo: https://lkml.org/lkml/2012/12/7/331 tglx: https://lkml.org/lkml/2012/12/10/437 srikar: https://lkml.org/lkml/2012/12/10/397 The results are a mixed bag. In my own tests, balancenuma does reasonably well. It's dumb as rocks and does not regress against mainline. On the other hand, Ingo's tests shows that balancenuma is incapable of converging for this workloads driven by perf which is bad but is potentially explained by the lack of scheduler smarts. Thomas' results show balancenuma improves on mainline but falls far short of numacore or autonuma. Srikar's results indicate we all suffer on a large machine with imbalanced node sizes. My own testing showed that recent numacore results have improved dramatically, particularly in the last week but not universally. We've butted heads heavily on system CPU usage and high levels of migration even when it shows that overall performance is better. There are also cases where it regresses. Of interest is that for specjbb in some configurations it will regress for lower numbers of warehouses and show gains for higher numbers which is not reported by the tool by default and sometimes missed in treports. Recently I reported for numacore that the JVM was crashing with NullPointerExceptions but currently it's unclear what the source of this problem is. Initially I thought it was in how numacore batch handles PTEs but I'm no longer think this is the case. It's possible numacore is just able to trigger it due to higher rates of migration. These reports were quite late in the cycle so I/we would like to start with this tree as it contains much of the code we can agree on and has not changed significantly over the last 2-3 weeks." * tag 'balancenuma-v11' of git://git.kernel.org/pub/scm/linux/kernel/git/mel/linux-balancenuma: (50 commits) mm/rmap, migration: Make rmap_walk_anon() and try_to_unmap_anon() more scalable mm/rmap: Convert the struct anon_vma::mutex to an rwsem mm: migrate: Account a transhuge page properly when rate limiting mm: numa: Account for failed allocations and isolations as migration failures mm: numa: Add THP migration for the NUMA working set scanning fault case build fix mm: numa: Add THP migration for the NUMA working set scanning fault case. mm: sched: numa: Delay PTE scanning until a task is scheduled on a new node mm: sched: numa: Control enabling and disabling of NUMA balancing if !SCHED_DEBUG mm: sched: numa: Control enabling and disabling of NUMA balancing mm: sched: Adapt the scanning rate if a NUMA hinting fault does not migrate mm: numa: Use a two-stage filter to restrict pages being migrated for unlikely task<->node relationships mm: numa: migrate: Set last_nid on newly allocated page mm: numa: split_huge_page: Transfer last_nid on tail page mm: numa: Introduce last_nid to the page frame sched: numa: Slowly increase the scanning period as NUMA faults are handled mm: numa: Rate limit setting of pte_numa if node is saturated mm: numa: Rate limit the amount of memory that is migrated between nodes mm: numa: Structures for Migrate On Fault per NUMA migration rate limiting mm: numa: Migrate pages handled during a pmd_numa hinting fault mm: numa: Migrate on reference policy ...
Diffstat (limited to 'mm/rmap.c')
-rw-r--r--mm/rmap.c66
1 files changed, 33 insertions, 33 deletions
diff --git a/mm/rmap.c b/mm/rmap.c
index face808a489e..2c78f8cadc95 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -24,7 +24,7 @@
* mm->mmap_sem
* page->flags PG_locked (lock_page)
* mapping->i_mmap_mutex
- * anon_vma->mutex
+ * anon_vma->rwsem
* mm->page_table_lock or pte_lock
* zone->lru_lock (in mark_page_accessed, isolate_lru_page)
* swap_lock (in swap_duplicate, swap_info_get)
@@ -37,7 +37,7 @@
* in arch-dependent flush_dcache_mmap_lock,
* within bdi.wb->list_lock in __sync_single_inode)
*
- * anon_vma->mutex,mapping->i_mutex (memory_failure, collect_procs_anon)
+ * anon_vma->rwsem,mapping->i_mutex (memory_failure, collect_procs_anon)
* ->tasklist_lock
* pte map lock
*/
@@ -87,24 +87,24 @@ static inline void anon_vma_free(struct anon_vma *anon_vma)
VM_BUG_ON(atomic_read(&anon_vma->refcount));
/*
- * Synchronize against page_lock_anon_vma() such that
+ * Synchronize against page_lock_anon_vma_read() such that
* we can safely hold the lock without the anon_vma getting
* freed.
*
* Relies on the full mb implied by the atomic_dec_and_test() from
* put_anon_vma() against the acquire barrier implied by
- * mutex_trylock() from page_lock_anon_vma(). This orders:
+ * down_read_trylock() from page_lock_anon_vma_read(). This orders:
*
- * page_lock_anon_vma() VS put_anon_vma()
- * mutex_trylock() atomic_dec_and_test()
+ * page_lock_anon_vma_read() VS put_anon_vma()
+ * down_read_trylock() atomic_dec_and_test()
* LOCK MB
- * atomic_read() mutex_is_locked()
+ * atomic_read() rwsem_is_locked()
*
* LOCK should suffice since the actual taking of the lock must
* happen _before_ what follows.
*/
- if (mutex_is_locked(&anon_vma->root->mutex)) {
- anon_vma_lock(anon_vma);
+ if (rwsem_is_locked(&anon_vma->root->rwsem)) {
+ anon_vma_lock_write(anon_vma);
anon_vma_unlock(anon_vma);
}
@@ -146,7 +146,7 @@ static void anon_vma_chain_link(struct vm_area_struct *vma,
* allocate a new one.
*
* Anon-vma allocations are very subtle, because we may have
- * optimistically looked up an anon_vma in page_lock_anon_vma()
+ * optimistically looked up an anon_vma in page_lock_anon_vma_read()
* and that may actually touch the spinlock even in the newly
* allocated vma (it depends on RCU to make sure that the
* anon_vma isn't actually destroyed).
@@ -181,7 +181,7 @@ int anon_vma_prepare(struct vm_area_struct *vma)
allocated = anon_vma;
}
- anon_vma_lock(anon_vma);
+ anon_vma_lock_write(anon_vma);
/* page_table_lock to protect against threads */
spin_lock(&mm->page_table_lock);
if (likely(!vma->anon_vma)) {
@@ -219,9 +219,9 @@ static inline struct anon_vma *lock_anon_vma_root(struct anon_vma *root, struct
struct anon_vma *new_root = anon_vma->root;
if (new_root != root) {
if (WARN_ON_ONCE(root))
- mutex_unlock(&root->mutex);
+ up_write(&root->rwsem);
root = new_root;
- mutex_lock(&root->mutex);
+ down_write(&root->rwsem);
}
return root;
}
@@ -229,7 +229,7 @@ static inline struct anon_vma *lock_anon_vma_root(struct anon_vma *root, struct
static inline void unlock_anon_vma_root(struct anon_vma *root)
{
if (root)
- mutex_unlock(&root->mutex);
+ up_write(&root->rwsem);
}
/*
@@ -306,7 +306,7 @@ int anon_vma_fork(struct vm_area_struct *vma, struct vm_area_struct *pvma)
get_anon_vma(anon_vma->root);
/* Mark this anon_vma as the one where our new (COWed) pages go. */
vma->anon_vma = anon_vma;
- anon_vma_lock(anon_vma);
+ anon_vma_lock_write(anon_vma);
anon_vma_chain_link(vma, avc, anon_vma);
anon_vma_unlock(anon_vma);
@@ -349,7 +349,7 @@ void unlink_anon_vmas(struct vm_area_struct *vma)
/*
* Iterate the list once more, it now only contains empty and unlinked
* anon_vmas, destroy them. Could not do before due to __put_anon_vma()
- * needing to acquire the anon_vma->root->mutex.
+ * needing to write-acquire the anon_vma->root->rwsem.
*/
list_for_each_entry_safe(avc, next, &vma->anon_vma_chain, same_vma) {
struct anon_vma *anon_vma = avc->anon_vma;
@@ -365,7 +365,7 @@ static void anon_vma_ctor(void *data)
{
struct anon_vma *anon_vma = data;
- mutex_init(&anon_vma->mutex);
+ init_rwsem(&anon_vma->rwsem);
atomic_set(&anon_vma->refcount, 0);
anon_vma->rb_root = RB_ROOT;
}
@@ -442,7 +442,7 @@ out:
* atomic op -- the trylock. If we fail the trylock, we fall back to getting a
* reference like with page_get_anon_vma() and then block on the mutex.
*/
-struct anon_vma *page_lock_anon_vma(struct page *page)
+struct anon_vma *page_lock_anon_vma_read(struct page *page)
{
struct anon_vma *anon_vma = NULL;
struct anon_vma *root_anon_vma;
@@ -457,14 +457,14 @@ struct anon_vma *page_lock_anon_vma(struct page *page)
anon_vma = (struct anon_vma *) (anon_mapping - PAGE_MAPPING_ANON);
root_anon_vma = ACCESS_ONCE(anon_vma->root);
- if (mutex_trylock(&root_anon_vma->mutex)) {
+ if (down_read_trylock(&root_anon_vma->rwsem)) {
/*
* If the page is still mapped, then this anon_vma is still
* its anon_vma, and holding the mutex ensures that it will
* not go away, see anon_vma_free().
*/
if (!page_mapped(page)) {
- mutex_unlock(&root_anon_vma->mutex);
+ up_read(&root_anon_vma->rwsem);
anon_vma = NULL;
}
goto out;
@@ -484,15 +484,15 @@ struct anon_vma *page_lock_anon_vma(struct page *page)
/* we pinned the anon_vma, its safe to sleep */
rcu_read_unlock();
- anon_vma_lock(anon_vma);
+ anon_vma_lock_read(anon_vma);
if (atomic_dec_and_test(&anon_vma->refcount)) {
/*
* Oops, we held the last refcount, release the lock
* and bail -- can't simply use put_anon_vma() because
- * we'll deadlock on the anon_vma_lock() recursion.
+ * we'll deadlock on the anon_vma_lock_write() recursion.
*/
- anon_vma_unlock(anon_vma);
+ anon_vma_unlock_read(anon_vma);
__put_anon_vma(anon_vma);
anon_vma = NULL;
}
@@ -504,9 +504,9 @@ out:
return anon_vma;
}
-void page_unlock_anon_vma(struct anon_vma *anon_vma)
+void page_unlock_anon_vma_read(struct anon_vma *anon_vma)
{
- anon_vma_unlock(anon_vma);
+ anon_vma_unlock_read(anon_vma);
}
/*
@@ -744,7 +744,7 @@ static int page_referenced_anon(struct page *page,
struct anon_vma_chain *avc;
int referenced = 0;
- anon_vma = page_lock_anon_vma(page);
+ anon_vma = page_lock_anon_vma_read(page);
if (!anon_vma)
return referenced;
@@ -766,7 +766,7 @@ static int page_referenced_anon(struct page *page,
break;
}
- page_unlock_anon_vma(anon_vma);
+ page_unlock_anon_vma_read(anon_vma);
return referenced;
}
@@ -1315,7 +1315,7 @@ out_mlock:
/*
* We need mmap_sem locking, Otherwise VM_LOCKED check makes
* unstable result and race. Plus, We can't wait here because
- * we now hold anon_vma->mutex or mapping->i_mmap_mutex.
+ * we now hold anon_vma->rwsem or mapping->i_mmap_mutex.
* if trylock failed, the page remain in evictable lru and later
* vmscan could retry to move the page to unevictable lru if the
* page is actually mlocked.
@@ -1480,7 +1480,7 @@ static int try_to_unmap_anon(struct page *page, enum ttu_flags flags)
struct anon_vma_chain *avc;
int ret = SWAP_AGAIN;
- anon_vma = page_lock_anon_vma(page);
+ anon_vma = page_lock_anon_vma_read(page);
if (!anon_vma)
return ret;
@@ -1507,7 +1507,7 @@ static int try_to_unmap_anon(struct page *page, enum ttu_flags flags)
break;
}
- page_unlock_anon_vma(anon_vma);
+ page_unlock_anon_vma_read(anon_vma);
return ret;
}
@@ -1702,7 +1702,7 @@ static int rmap_walk_anon(struct page *page, int (*rmap_one)(struct page *,
int ret = SWAP_AGAIN;
/*
- * Note: remove_migration_ptes() cannot use page_lock_anon_vma()
+ * Note: remove_migration_ptes() cannot use page_lock_anon_vma_read()
* because that depends on page_mapped(); but not all its usages
* are holding mmap_sem. Users without mmap_sem are required to
* take a reference count to prevent the anon_vma disappearing
@@ -1710,7 +1710,7 @@ static int rmap_walk_anon(struct page *page, int (*rmap_one)(struct page *,
anon_vma = page_anon_vma(page);
if (!anon_vma)
return ret;
- anon_vma_lock(anon_vma);
+ anon_vma_lock_read(anon_vma);
anon_vma_interval_tree_foreach(avc, &anon_vma->rb_root, pgoff, pgoff) {
struct vm_area_struct *vma = avc->vma;
unsigned long address = vma_address(page, vma);
@@ -1718,7 +1718,7 @@ static int rmap_walk_anon(struct page *page, int (*rmap_one)(struct page *,
if (ret != SWAP_AGAIN)
break;
}
- anon_vma_unlock(anon_vma);
+ anon_vma_unlock_read(anon_vma);
return ret;
}