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Diffstat (limited to 'mm')
-rw-r--r--mm/backing-dev.c52
-rw-r--r--mm/compaction.c156
-rw-r--r--mm/internal.h1
-rw-r--r--mm/mmap.c7
-rw-r--r--mm/page-writeback.c1
-rw-r--r--mm/page_alloc.c40
6 files changed, 135 insertions, 122 deletions
diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index 6b4718e2ee34..b41823cc05e6 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -39,12 +39,6 @@ DEFINE_SPINLOCK(bdi_lock);
LIST_HEAD(bdi_list);
LIST_HEAD(bdi_pending_list);
-static struct task_struct *sync_supers_tsk;
-static struct timer_list sync_supers_timer;
-
-static int bdi_sync_supers(void *);
-static void sync_supers_timer_fn(unsigned long);
-
void bdi_lock_two(struct bdi_writeback *wb1, struct bdi_writeback *wb2)
{
if (wb1 < wb2) {
@@ -250,12 +244,6 @@ static int __init default_bdi_init(void)
{
int err;
- sync_supers_tsk = kthread_run(bdi_sync_supers, NULL, "sync_supers");
- BUG_ON(IS_ERR(sync_supers_tsk));
-
- setup_timer(&sync_supers_timer, sync_supers_timer_fn, 0);
- bdi_arm_supers_timer();
-
err = bdi_init(&default_backing_dev_info);
if (!err)
bdi_register(&default_backing_dev_info, NULL, "default");
@@ -270,46 +258,6 @@ int bdi_has_dirty_io(struct backing_dev_info *bdi)
return wb_has_dirty_io(&bdi->wb);
}
-/*
- * kupdated() used to do this. We cannot do it from the bdi_forker_thread()
- * or we risk deadlocking on ->s_umount. The longer term solution would be
- * to implement sync_supers_bdi() or similar and simply do it from the
- * bdi writeback thread individually.
- */
-static int bdi_sync_supers(void *unused)
-{
- set_user_nice(current, 0);
-
- while (!kthread_should_stop()) {
- set_current_state(TASK_INTERRUPTIBLE);
- schedule();
-
- /*
- * Do this periodically, like kupdated() did before.
- */
- sync_supers();
- }
-
- return 0;
-}
-
-void bdi_arm_supers_timer(void)
-{
- unsigned long next;
-
- if (!dirty_writeback_interval)
- return;
-
- next = msecs_to_jiffies(dirty_writeback_interval * 10) + jiffies;
- mod_timer(&sync_supers_timer, round_jiffies_up(next));
-}
-
-static void sync_supers_timer_fn(unsigned long unused)
-{
- wake_up_process(sync_supers_tsk);
- bdi_arm_supers_timer();
-}
-
static void wakeup_timer_fn(unsigned long data)
{
struct backing_dev_info *bdi = (struct backing_dev_info *)data;
diff --git a/mm/compaction.c b/mm/compaction.c
index e78cb9688421..7fcd3a52e68d 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -51,6 +51,47 @@ static inline bool migrate_async_suitable(int migratetype)
}
/*
+ * Compaction requires the taking of some coarse locks that are potentially
+ * very heavily contended. Check if the process needs to be scheduled or
+ * if the lock is contended. For async compaction, back out in the event
+ * if contention is severe. For sync compaction, schedule.
+ *
+ * Returns true if the lock is held.
+ * Returns false if the lock is released and compaction should abort
+ */
+static bool compact_checklock_irqsave(spinlock_t *lock, unsigned long *flags,
+ bool locked, struct compact_control *cc)
+{
+ if (need_resched() || spin_is_contended(lock)) {
+ if (locked) {
+ spin_unlock_irqrestore(lock, *flags);
+ locked = false;
+ }
+
+ /* async aborts if taking too long or contended */
+ if (!cc->sync) {
+ if (cc->contended)
+ *cc->contended = true;
+ return false;
+ }
+
+ cond_resched();
+ if (fatal_signal_pending(current))
+ return false;
+ }
+
+ if (!locked)
+ spin_lock_irqsave(lock, *flags);
+ return true;
+}
+
+static inline bool compact_trylock_irqsave(spinlock_t *lock,
+ unsigned long *flags, struct compact_control *cc)
+{
+ return compact_checklock_irqsave(lock, flags, false, cc);
+}
+
+/*
* Isolate free pages onto a private freelist. Caller must hold zone->lock.
* If @strict is true, will abort returning 0 on any invalid PFNs or non-free
* pages inside of the pageblock (even though it may still end up isolating
@@ -173,7 +214,7 @@ isolate_freepages_range(unsigned long start_pfn, unsigned long end_pfn)
}
/* Update the number of anon and file isolated pages in the zone */
-static void acct_isolated(struct zone *zone, struct compact_control *cc)
+static void acct_isolated(struct zone *zone, bool locked, struct compact_control *cc)
{
struct page *page;
unsigned int count[2] = { 0, };
@@ -181,8 +222,14 @@ static void acct_isolated(struct zone *zone, struct compact_control *cc)
list_for_each_entry(page, &cc->migratepages, lru)
count[!!page_is_file_cache(page)]++;
- __mod_zone_page_state(zone, NR_ISOLATED_ANON, count[0]);
- __mod_zone_page_state(zone, NR_ISOLATED_FILE, count[1]);
+ /* If locked we can use the interrupt unsafe versions */
+ if (locked) {
+ __mod_zone_page_state(zone, NR_ISOLATED_ANON, count[0]);
+ __mod_zone_page_state(zone, NR_ISOLATED_FILE, count[1]);
+ } else {
+ mod_zone_page_state(zone, NR_ISOLATED_ANON, count[0]);
+ mod_zone_page_state(zone, NR_ISOLATED_FILE, count[1]);
+ }
}
/* Similar to reclaim, but different enough that they don't share logic */
@@ -228,6 +275,8 @@ isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
struct list_head *migratelist = &cc->migratepages;
isolate_mode_t mode = 0;
struct lruvec *lruvec;
+ unsigned long flags;
+ bool locked;
/*
* Ensure that there are not too many pages isolated from the LRU
@@ -247,25 +296,22 @@ isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
/* Time to isolate some pages for migration */
cond_resched();
- spin_lock_irq(&zone->lru_lock);
+ spin_lock_irqsave(&zone->lru_lock, flags);
+ locked = true;
for (; low_pfn < end_pfn; low_pfn++) {
struct page *page;
- bool locked = true;
/* give a chance to irqs before checking need_resched() */
if (!((low_pfn+1) % SWAP_CLUSTER_MAX)) {
- spin_unlock_irq(&zone->lru_lock);
+ spin_unlock_irqrestore(&zone->lru_lock, flags);
locked = false;
}
- if (need_resched() || spin_is_contended(&zone->lru_lock)) {
- if (locked)
- spin_unlock_irq(&zone->lru_lock);
- cond_resched();
- spin_lock_irq(&zone->lru_lock);
- if (fatal_signal_pending(current))
- break;
- } else if (!locked)
- spin_lock_irq(&zone->lru_lock);
+
+ /* Check if it is ok to still hold the lock */
+ locked = compact_checklock_irqsave(&zone->lru_lock, &flags,
+ locked, cc);
+ if (!locked)
+ break;
/*
* migrate_pfn does not necessarily start aligned to a
@@ -349,9 +395,10 @@ isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
}
}
- acct_isolated(zone, cc);
+ acct_isolated(zone, locked, cc);
- spin_unlock_irq(&zone->lru_lock);
+ if (locked)
+ spin_unlock_irqrestore(&zone->lru_lock, flags);
trace_mm_compaction_isolate_migratepages(nr_scanned, nr_isolated);
@@ -384,6 +431,20 @@ static bool suitable_migration_target(struct page *page)
}
/*
+ * Returns the start pfn of the last page block in a zone. This is the starting
+ * point for full compaction of a zone. Compaction searches for free pages from
+ * the end of each zone, while isolate_freepages_block scans forward inside each
+ * page block.
+ */
+static unsigned long start_free_pfn(struct zone *zone)
+{
+ unsigned long free_pfn;
+ free_pfn = zone->zone_start_pfn + zone->spanned_pages;
+ free_pfn &= ~(pageblock_nr_pages-1);
+ return free_pfn;
+}
+
+/*
* Based on information in the current compact_control, find blocks
* suitable for isolating free pages from and then isolate them.
*/
@@ -422,17 +483,6 @@ static void isolate_freepages(struct zone *zone,
pfn -= pageblock_nr_pages) {
unsigned long isolated;
- /*
- * Skip ahead if another thread is compacting in the area
- * simultaneously. If we wrapped around, we can only skip
- * ahead if zone->compact_cached_free_pfn also wrapped to
- * above our starting point.
- */
- if (cc->order > 0 && (!cc->wrapped ||
- zone->compact_cached_free_pfn >
- cc->start_free_pfn))
- pfn = min(pfn, zone->compact_cached_free_pfn);
-
if (!pfn_valid(pfn))
continue;
@@ -458,7 +508,16 @@ static void isolate_freepages(struct zone *zone,
* are disabled
*/
isolated = 0;
- spin_lock_irqsave(&zone->lock, flags);
+
+ /*
+ * The zone lock must be held to isolate freepages. This
+ * unfortunately this is a very coarse lock and can be
+ * heavily contended if there are parallel allocations
+ * or parallel compactions. For async compaction do not
+ * spin on the lock
+ */
+ if (!compact_trylock_irqsave(&zone->lock, &flags, cc))
+ break;
if (suitable_migration_target(page)) {
end_pfn = min(pfn + pageblock_nr_pages, zone_end_pfn);
isolated = isolate_freepages_block(pfn, end_pfn,
@@ -474,7 +533,15 @@ static void isolate_freepages(struct zone *zone,
*/
if (isolated) {
high_pfn = max(high_pfn, pfn);
- if (cc->order > 0)
+
+ /*
+ * If the free scanner has wrapped, update
+ * compact_cached_free_pfn to point to the highest
+ * pageblock with free pages. This reduces excessive
+ * scanning of full pageblocks near the end of the
+ * zone
+ */
+ if (cc->order > 0 && cc->wrapped)
zone->compact_cached_free_pfn = high_pfn;
}
}
@@ -484,6 +551,11 @@ static void isolate_freepages(struct zone *zone,
cc->free_pfn = high_pfn;
cc->nr_freepages = nr_freepages;
+
+ /* If compact_cached_free_pfn is reset then set it now */
+ if (cc->order > 0 && !cc->wrapped &&
+ zone->compact_cached_free_pfn == start_free_pfn(zone))
+ zone->compact_cached_free_pfn = high_pfn;
}
/*
@@ -570,20 +642,6 @@ static isolate_migrate_t isolate_migratepages(struct zone *zone,
return ISOLATE_SUCCESS;
}
-/*
- * Returns the start pfn of the last page block in a zone. This is the starting
- * point for full compaction of a zone. Compaction searches for free pages from
- * the end of each zone, while isolate_freepages_block scans forward inside each
- * page block.
- */
-static unsigned long start_free_pfn(struct zone *zone)
-{
- unsigned long free_pfn;
- free_pfn = zone->zone_start_pfn + zone->spanned_pages;
- free_pfn &= ~(pageblock_nr_pages-1);
- return free_pfn;
-}
-
static int compact_finished(struct zone *zone,
struct compact_control *cc)
{
@@ -771,7 +829,7 @@ out:
static unsigned long compact_zone_order(struct zone *zone,
int order, gfp_t gfp_mask,
- bool sync)
+ bool sync, bool *contended)
{
struct compact_control cc = {
.nr_freepages = 0,
@@ -780,6 +838,7 @@ static unsigned long compact_zone_order(struct zone *zone,
.migratetype = allocflags_to_migratetype(gfp_mask),
.zone = zone,
.sync = sync,
+ .contended = contended,
};
INIT_LIST_HEAD(&cc.freepages);
INIT_LIST_HEAD(&cc.migratepages);
@@ -801,7 +860,7 @@ int sysctl_extfrag_threshold = 500;
*/
unsigned long try_to_compact_pages(struct zonelist *zonelist,
int order, gfp_t gfp_mask, nodemask_t *nodemask,
- bool sync)
+ bool sync, bool *contended)
{
enum zone_type high_zoneidx = gfp_zone(gfp_mask);
int may_enter_fs = gfp_mask & __GFP_FS;
@@ -825,7 +884,8 @@ unsigned long try_to_compact_pages(struct zonelist *zonelist,
nodemask) {
int status;
- status = compact_zone_order(zone, order, gfp_mask, sync);
+ status = compact_zone_order(zone, order, gfp_mask, sync,
+ contended);
rc = max(status, rc);
/* If a normal allocation would succeed, stop compacting */
@@ -861,7 +921,7 @@ static int __compact_pgdat(pg_data_t *pgdat, struct compact_control *cc)
if (cc->order > 0) {
int ok = zone_watermark_ok(zone, cc->order,
low_wmark_pages(zone), 0, 0);
- if (ok && cc->order > zone->compact_order_failed)
+ if (ok && cc->order >= zone->compact_order_failed)
zone->compact_order_failed = cc->order + 1;
/* Currently async compaction is never deferred. */
else if (!ok && cc->sync)
diff --git a/mm/internal.h b/mm/internal.h
index 3314f79d775a..b8c91b342e24 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -130,6 +130,7 @@ struct compact_control {
int order; /* order a direct compactor needs */
int migratetype; /* MOVABLE, RECLAIMABLE etc */
struct zone *zone;
+ bool *contended; /* True if a lock was contended */
};
unsigned long
diff --git a/mm/mmap.c b/mm/mmap.c
index e3e86914f11a..ae18a48e7e4e 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1356,9 +1356,8 @@ out:
} else if ((flags & MAP_POPULATE) && !(flags & MAP_NONBLOCK))
make_pages_present(addr, addr + len);
- if (file && uprobe_mmap(vma))
- /* matching probes but cannot insert */
- goto unmap_and_free_vma;
+ if (file)
+ uprobe_mmap(vma);
return addr;
@@ -2309,7 +2308,7 @@ void exit_mmap(struct mm_struct *mm)
}
vm_unacct_memory(nr_accounted);
- BUG_ON(mm->nr_ptes > (FIRST_USER_ADDRESS+PMD_SIZE-1)>>PMD_SHIFT);
+ WARN_ON(mm->nr_ptes > (FIRST_USER_ADDRESS+PMD_SIZE-1)>>PMD_SHIFT);
}
/* Insert vm structure into process list sorted by address
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index e5363f34e025..5ad5ce23c1e0 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -1532,7 +1532,6 @@ int dirty_writeback_centisecs_handler(ctl_table *table, int write,
void __user *buffer, size_t *length, loff_t *ppos)
{
proc_dointvec(table, write, buffer, length, ppos);
- bdi_arm_supers_timer();
return 0;
}
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 889532b8e6c1..c66fb875104a 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1928,6 +1928,17 @@ this_zone_full:
zlc_active = 0;
goto zonelist_scan;
}
+
+ if (page)
+ /*
+ * page->pfmemalloc is set when ALLOC_NO_WATERMARKS was
+ * necessary to allocate the page. The expectation is
+ * that the caller is taking steps that will free more
+ * memory. The caller should avoid the page being used
+ * for !PFMEMALLOC purposes.
+ */
+ page->pfmemalloc = !!(alloc_flags & ALLOC_NO_WATERMARKS);
+
return page;
}
@@ -2091,7 +2102,7 @@ __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
struct zonelist *zonelist, enum zone_type high_zoneidx,
nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
int migratetype, bool sync_migration,
- bool *deferred_compaction,
+ bool *contended_compaction, bool *deferred_compaction,
unsigned long *did_some_progress)
{
struct page *page;
@@ -2106,7 +2117,8 @@ __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
current->flags |= PF_MEMALLOC;
*did_some_progress = try_to_compact_pages(zonelist, order, gfp_mask,
- nodemask, sync_migration);
+ nodemask, sync_migration,
+ contended_compaction);
current->flags &= ~PF_MEMALLOC;
if (*did_some_progress != COMPACT_SKIPPED) {
@@ -2152,7 +2164,7 @@ __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
struct zonelist *zonelist, enum zone_type high_zoneidx,
nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
int migratetype, bool sync_migration,
- bool *deferred_compaction,
+ bool *contended_compaction, bool *deferred_compaction,
unsigned long *did_some_progress)
{
return NULL;
@@ -2325,6 +2337,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
unsigned long did_some_progress;
bool sync_migration = false;
bool deferred_compaction = false;
+ bool contended_compaction = false;
/*
* In the slowpath, we sanity check order to avoid ever trying to
@@ -2389,14 +2402,6 @@ rebalance:
zonelist, high_zoneidx, nodemask,
preferred_zone, migratetype);
if (page) {
- /*
- * page->pfmemalloc is set when ALLOC_NO_WATERMARKS was
- * necessary to allocate the page. The expectation is
- * that the caller is taking steps that will free more
- * memory. The caller should avoid the page being used
- * for !PFMEMALLOC purposes.
- */
- page->pfmemalloc = true;
goto got_pg;
}
}
@@ -2422,6 +2427,7 @@ rebalance:
nodemask,
alloc_flags, preferred_zone,
migratetype, sync_migration,
+ &contended_compaction,
&deferred_compaction,
&did_some_progress);
if (page)
@@ -2431,10 +2437,11 @@ rebalance:
/*
* If compaction is deferred for high-order allocations, it is because
* sync compaction recently failed. In this is the case and the caller
- * has requested the system not be heavily disrupted, fail the
- * allocation now instead of entering direct reclaim
+ * requested a movable allocation that does not heavily disrupt the
+ * system then fail the allocation instead of entering direct reclaim.
*/
- if (deferred_compaction && (gfp_mask & __GFP_NO_KSWAPD))
+ if ((deferred_compaction || contended_compaction) &&
+ (gfp_mask & __GFP_NO_KSWAPD))
goto nopage;
/* Try direct reclaim and then allocating */
@@ -2505,6 +2512,7 @@ rebalance:
nodemask,
alloc_flags, preferred_zone,
migratetype, sync_migration,
+ &contended_compaction,
&deferred_compaction,
&did_some_progress);
if (page)
@@ -2569,8 +2577,6 @@ retry_cpuset:
page = __alloc_pages_slowpath(gfp_mask, order,
zonelist, high_zoneidx, nodemask,
preferred_zone, migratetype);
- else
- page->pfmemalloc = false;
trace_mm_page_alloc(page, order, gfp_mask, migratetype);
@@ -4511,7 +4517,7 @@ void __paginginit free_area_init_node(int nid, unsigned long *zones_size,
pg_data_t *pgdat = NODE_DATA(nid);
/* pg_data_t should be reset to zero when it's allocated */
- WARN_ON(pgdat->nr_zones || pgdat->node_start_pfn || pgdat->classzone_idx);
+ WARN_ON(pgdat->nr_zones || pgdat->classzone_idx);
pgdat->node_id = nid;
pgdat->node_start_pfn = node_start_pfn;