lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <1433771791-30567-23-git-send-email-mgorman@suse.de>
Date:	Mon,  8 Jun 2015 14:56:28 +0100
From:	Mel Gorman <mgorman@...e.de>
To:	Linux-MM <linux-mm@...ck.org>
Cc:	Rik van Riel <riel@...hat.com>,
	Johannes Weiner <hannes@...xchg.org>,
	Michal Hocko <mhocko@...e.cz>,
	LKML <linux-kernel@...r.kernel.org>, Mel Gorman <mgorman@...e.de>
Subject: [PATCH 22/25] mm: Convert zone_reclaim to node_reclaim

As reclaim is now per-node based, convert zone_reclaim to be node_reclaim
and avoid reclaiming a node multiple times due to having multiple populated
zones. The documentation and interface to userspace is the same as from
a configuration and behaviour perspective, it will be similar unless the
node-local allocation requests were also limited to lower zones.

Signed-off-by: Mel Gorman <mgorman@...e.de>
---
 include/linux/mmzone.h   | 18 +++++------
 include/linux/swap.h     |  9 +++---
 include/linux/topology.h |  2 +-
 kernel/sysctl.c          |  4 +--
 mm/huge_memory.c         |  4 +--
 mm/internal.h            |  8 ++---
 mm/page_alloc.c          | 35 +++++++++++++++-------
 mm/vmscan.c              | 77 ++++++++++++++++++++++++------------------------
 8 files changed, 85 insertions(+), 72 deletions(-)

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index c551f70951fa..84fcb7aafb2b 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -362,14 +362,6 @@ struct zone {
 	unsigned long		*pageblock_flags;
 #endif /* CONFIG_SPARSEMEM */
 
-#ifdef CONFIG_NUMA
-	/*
-	 * zone reclaim becomes active if more unmapped pages exist.
-	 */
-	unsigned long		min_unmapped_pages;
-	unsigned long		min_slab_pages;
-#endif /* CONFIG_NUMA */
-
 	/* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */
 	unsigned long		zone_start_pfn;
 
@@ -518,7 +510,6 @@ struct zone {
 } ____cacheline_internodealigned_in_smp;
 
 enum zone_flags {
-	ZONE_RECLAIM_LOCKED,		/* prevents concurrent reclaim */
 	ZONE_OOM_LOCKED,		/* zone is in OOM killer zonelist */
 };
 
@@ -533,6 +524,7 @@ enum pgdat_flags {
 	PGDAT_WRITEBACK,		/* reclaim scanning has recently found
 					 * many pages under writeback
 					 */
+	PGDAT_RECLAIM_LOCKED,		/* prevents concurrent reclaim */
 };
 
 static inline unsigned long zone_end_pfn(const struct zone *zone)
@@ -758,6 +750,14 @@ typedef struct pglist_data {
 	 */
 	unsigned long		dirty_balance_reserve;
 
+#ifdef CONFIG_NUMA
+	/*
+	 * zone reclaim becomes active if more unmapped pages exist.
+	 */
+	unsigned long		min_unmapped_pages;
+	unsigned long		min_slab_pages;
+#endif /* CONFIG_NUMA */
+
 	/* Write-intensive fields used from the page allocator */
 	ZONE_PADDING(_pad1_)
 	spinlock_t		lru_lock;
diff --git a/include/linux/swap.h b/include/linux/swap.h
index bb9597213e39..59d70fd04ec8 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -333,13 +333,14 @@ extern int remove_mapping(struct address_space *mapping, struct page *page);
 extern unsigned long vm_total_pages;
 
 #ifdef CONFIG_NUMA
-extern int zone_reclaim_mode;
+extern int node_reclaim_mode;
 extern int sysctl_min_unmapped_ratio;
 extern int sysctl_min_slab_ratio;
-extern int zone_reclaim(struct zone *, gfp_t, unsigned int);
+extern int node_reclaim(struct pglist_data *, gfp_t, unsigned int);
 #else
-#define zone_reclaim_mode 0
-static inline int zone_reclaim(struct zone *z, gfp_t mask, unsigned int order)
+#define node_reclaim_mode 0
+static inline int node_reclaim(struct pglist_data *pgdat, gfp_t mask,
+				unsigned int order)
 {
 	return 0;
 }
diff --git a/include/linux/topology.h b/include/linux/topology.h
index 909b6e43b694..55a9b2bbb4de 100644
--- a/include/linux/topology.h
+++ b/include/linux/topology.h
@@ -58,7 +58,7 @@ int arch_update_cpu_topology(void);
 /*
  * If the distance between nodes in a system is larger than RECLAIM_DISTANCE
  * (in whatever arch specific measurement units returned by node_distance())
- * and zone_reclaim_mode is enabled then the VM will only call zone_reclaim()
+ * and node_reclaim_mode is enabled then the VM will only call node_reclaim()
  * on nodes within this distance.
  */
 #define RECLAIM_DISTANCE 30
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index ce410bb9f2e1..f80921283f06 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -1394,8 +1394,8 @@ static struct ctl_table vm_table[] = {
 #ifdef CONFIG_NUMA
 	{
 		.procname	= "zone_reclaim_mode",
-		.data		= &zone_reclaim_mode,
-		.maxlen		= sizeof(zone_reclaim_mode),
+		.data		= &node_reclaim_mode,
+		.maxlen		= sizeof(node_reclaim_mode),
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec,
 		.extra1		= &zero,
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index b56c14a41d96..a5c4e36f200c 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2249,10 +2249,10 @@ static bool khugepaged_scan_abort(int nid)
 	int i;
 
 	/*
-	 * If zone_reclaim_mode is disabled, then no extra effort is made to
+	 * If node_reclaim_mode is disabled, then no extra effort is made to
 	 * allocate memory locally.
 	 */
-	if (!zone_reclaim_mode)
+	if (!node_reclaim_mode)
 		return false;
 
 	/* If there is a count for this node already, it must be acceptable */
diff --git a/mm/internal.h b/mm/internal.h
index a24c4a50c33f..a0b0d20ead97 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -395,10 +395,10 @@ static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn,
 }
 #endif /* CONFIG_SPARSEMEM */
 
-#define ZONE_RECLAIM_NOSCAN	-2
-#define ZONE_RECLAIM_FULL	-1
-#define ZONE_RECLAIM_SOME	0
-#define ZONE_RECLAIM_SUCCESS	1
+#define NODE_RECLAIM_NOSCAN	-2
+#define NODE_RECLAIM_FULL	-1
+#define NODE_RECLAIM_SOME	0
+#define NODE_RECLAIM_SUCCESS	1
 
 extern int hwpoison_filter(struct page *p);
 
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 637b293cd5d1..47e6332d7566 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2064,7 +2064,6 @@ zonelist_scan:
 					!node_dirty_ok(zone->zone_pgdat)) {
 			continue;
 		}
-		last_pgdat = zone->zone_pgdat;
 
 		mark = zone->watermark[alloc_flags & ALLOC_WMARK_MASK];
 		if (!zone_watermark_ok(zone, order, mark,
@@ -2076,7 +2075,7 @@ zonelist_scan:
 			if (alloc_flags & ALLOC_NO_WATERMARKS)
 				goto try_this_zone;
 
-			if (zone_reclaim_mode == 0 ||
+			if (node_reclaim_mode == 0 ||
 			    !zone_allows_reclaim(ac->preferred_zone, zone))
 				goto this_zone_full;
 
@@ -2094,18 +2093,22 @@ zonelist_scan:
 
 			/*
 			 * As we may have just activated ZLC, check if the first
-			 * eligible zone has failed zone_reclaim recently.
+			 * eligible zone has failed node_reclaim recently.
 			 */
 			if (IS_ENABLED(CONFIG_NUMA) && zlc_active &&
 				!zlc_zone_worth_trying(zonelist, z, allowednodes))
 				continue;
 
-			ret = zone_reclaim(zone, gfp_mask, order);
+			/* Skip if we have already attemped node_reclaim */
+			if (last_pgdat == zone->zone_pgdat)
+				goto try_this_zone;
+
+			ret = node_reclaim(zone->zone_pgdat, gfp_mask, order);
 			switch (ret) {
-			case ZONE_RECLAIM_NOSCAN:
+			case NODE_RECLAIM_NOSCAN:
 				/* did not scan */
 				continue;
-			case ZONE_RECLAIM_FULL:
+			case NODE_RECLAIM_FULL:
 				/* scanned but unreclaimable */
 				continue;
 			default:
@@ -2124,7 +2127,7 @@ zonelist_scan:
 				 * min watermarks.
 				 */
 				if (((alloc_flags & ALLOC_WMARK_MASK) == ALLOC_WMARK_MIN) ||
-				    ret == ZONE_RECLAIM_SOME)
+				    ret == NODE_RECLAIM_SOME)
 					goto this_zone_full;
 
 				continue;
@@ -2132,6 +2135,7 @@ zonelist_scan:
 		}
 
 try_this_zone:
+		last_pgdat = zone->zone_pgdat;
 		page = buffered_rmqueue(ac->preferred_zone, zone, order,
 						gfp_mask, ac->migratetype);
 		if (page) {
@@ -2140,6 +2144,7 @@ try_this_zone:
 			return page;
 		}
 this_zone_full:
+		last_pgdat = zone->zone_pgdat;
 		if (IS_ENABLED(CONFIG_NUMA) && zlc_active)
 			zlc_mark_zone_full(zonelist, z);
 	}
@@ -4879,9 +4884,9 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat,
 		zone->managed_pages = is_highmem_idx(j) ? realsize : freesize;
 #ifdef CONFIG_NUMA
 		zone->node = nid;
-		zone->min_unmapped_pages = (freesize*sysctl_min_unmapped_ratio)
+		pgdat->min_unmapped_pages += (freesize*sysctl_min_unmapped_ratio)
 						/ 100;
-		zone->min_slab_pages = (freesize * sysctl_min_slab_ratio) / 100;
+		pgdat->min_slab_pages += (freesize * sysctl_min_slab_ratio) / 100;
 #endif
 		zone->name = zone_names[j];
 		zone->zone_pgdat = pgdat;
@@ -5839,6 +5844,7 @@ int min_free_kbytes_sysctl_handler(struct ctl_table *table, int write,
 int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table *table, int write,
 	void __user *buffer, size_t *length, loff_t *ppos)
 {
+	struct pglist_data *pgdat;
 	struct zone *zone;
 	int rc;
 
@@ -5846,8 +5852,11 @@ int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table *table, int write,
 	if (rc)
 		return rc;
 
+	for_each_online_pgdat(pgdat)
+		pgdat->min_slab_pages = 0;
+
 	for_each_zone(zone)
-		zone->min_unmapped_pages = (zone->managed_pages *
+		zone->zone_pgdat->min_unmapped_pages += (zone->managed_pages *
 				sysctl_min_unmapped_ratio) / 100;
 	return 0;
 }
@@ -5855,6 +5864,7 @@ int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table *table, int write,
 int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table *table, int write,
 	void __user *buffer, size_t *length, loff_t *ppos)
 {
+	struct pglist_data *pgdat;
 	struct zone *zone;
 	int rc;
 
@@ -5862,8 +5872,11 @@ int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table *table, int write,
 	if (rc)
 		return rc;
 
+	for_each_online_pgdat(pgdat)
+		pgdat->min_slab_pages = 0;
+
 	for_each_zone(zone)
-		zone->min_slab_pages = (zone->managed_pages *
+		zone->zone_pgdat->min_slab_pages += (zone->managed_pages *
 				sysctl_min_slab_ratio) / 100;
 	return 0;
 }
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 3cb0cc70ddbd..cf9ae51c9a5c 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -3529,12 +3529,12 @@ module_init(kswapd_init)
 
 #ifdef CONFIG_NUMA
 /*
- * Zone reclaim mode
+ * Node reclaim mode
  *
- * If non-zero call zone_reclaim when the number of free pages falls below
+ * If non-zero call node_reclaim when the number of free pages falls below
  * the watermarks.
  */
-int zone_reclaim_mode __read_mostly;
+int node_reclaim_mode __read_mostly;
 
 #define RECLAIM_OFF 0
 #define RECLAIM_ZONE (1<<0)	/* Run shrink_inactive_list on the zone */
@@ -3542,14 +3542,14 @@ int zone_reclaim_mode __read_mostly;
 #define RECLAIM_SWAP (1<<2)	/* Swap pages out during reclaim */
 
 /*
- * Priority for ZONE_RECLAIM. This determines the fraction of pages
+ * Priority for NODE_RECLAIM. This determines the fraction of pages
  * of a node considered for each zone_reclaim. 4 scans 1/16th of
  * a zone.
  */
-#define ZONE_RECLAIM_PRIORITY 4
+#define NODE_RECLAIM_PRIORITY 4
 
 /*
- * Percentage of pages in a zone that must be unmapped for zone_reclaim to
+ * Percentage of pages in a zone that must be unmapped for node_reclaim to
  * occur.
  */
 int sysctl_min_unmapped_ratio = 1;
@@ -3575,9 +3575,9 @@ static inline unsigned long node_unmapped_file_pages(struct pglist_data *pgdat)
 }
 
 /* Work out how many page cache pages we can reclaim in this reclaim_mode */
-static long zone_pagecache_reclaimable(struct zone *zone)
+static long node_pagecache_reclaimable(struct pglist_data *pgdat)
 {
-	long nr_pagecache_reclaimable;
+	long nr_pagecache_reclaimable = 0;
 	long delta = 0;
 
 	/*
@@ -3586,14 +3586,14 @@ static long zone_pagecache_reclaimable(struct zone *zone)
 	 * pages like swapcache and node_unmapped_file_pages() provides
 	 * a better estimate
 	 */
-	if (zone_reclaim_mode & RECLAIM_SWAP)
-		nr_pagecache_reclaimable = node_page_state(zone->zone_pgdat, NR_FILE_PAGES);
+	if (node_reclaim_mode & RECLAIM_SWAP)
+		nr_pagecache_reclaimable = node_page_state(pgdat, NR_FILE_PAGES);
 	else
-		nr_pagecache_reclaimable = node_unmapped_file_pages(zone->zone_pgdat);
+		nr_pagecache_reclaimable = node_unmapped_file_pages(pgdat);
 
 	/* If we can't clean pages, remove dirty pages from consideration */
-	if (!(zone_reclaim_mode & RECLAIM_WRITE))
-		delta += node_page_state(zone->zone_pgdat, NR_FILE_DIRTY);
+	if (!(node_reclaim_mode & RECLAIM_WRITE))
+		delta += node_page_state(pgdat, NR_FILE_DIRTY);
 
 	/* Watch for any possible underflows due to delta */
 	if (unlikely(delta > nr_pagecache_reclaimable))
@@ -3603,21 +3603,22 @@ static long zone_pagecache_reclaimable(struct zone *zone)
 }
 
 /*
- * Try to free up some pages from this zone through reclaim.
+ * Try to free up some pages from this node through reclaim.
  */
-static int __zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
+static int __node_reclaim(struct pglist_data *pgdat, gfp_t gfp_mask, unsigned int order)
 {
 	/* Minimum pages needed in order to stay on node */
 	const unsigned long nr_pages = 1 << order;
 	struct task_struct *p = current;
 	struct reclaim_state reclaim_state;
+	int classzone_idx = gfp_zone(gfp_mask);
 	struct scan_control sc = {
 		.nr_to_reclaim = max(nr_pages, SWAP_CLUSTER_MAX),
 		.gfp_mask = (gfp_mask = memalloc_noio_flags(gfp_mask)),
 		.order = order,
-		.priority = ZONE_RECLAIM_PRIORITY,
-		.may_writepage = !!(zone_reclaim_mode & RECLAIM_WRITE),
-		.may_unmap = !!(zone_reclaim_mode & RECLAIM_SWAP),
+		.priority = NODE_RECLAIM_PRIORITY,
+		.may_writepage = !!(node_reclaim_mode & RECLAIM_WRITE),
+		.may_unmap = !!(node_reclaim_mode & RECLAIM_SWAP),
 		.may_swap = 1,
 	};
 
@@ -3632,13 +3633,13 @@ static int __zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
 	reclaim_state.reclaimed_slab = 0;
 	p->reclaim_state = &reclaim_state;
 
-	if (zone_pagecache_reclaimable(zone) > zone->min_unmapped_pages) {
+	if (node_pagecache_reclaimable(pgdat) > pgdat->min_unmapped_pages) {
 		/*
 		 * Free memory by calling shrink zone with increasing
 		 * priorities until we have enough memory freed.
 		 */
 		do {
-			shrink_node(zone->zone_pgdat, &sc, zone_idx(zone), zone_idx(zone));
+			shrink_node(pgdat, &sc, classzone_idx, classzone_idx);
 		} while (sc.nr_reclaimed < nr_pages && --sc.priority >= 0);
 	}
 
@@ -3648,49 +3649,47 @@ static int __zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
 	return sc.nr_reclaimed >= nr_pages;
 }
 
-int zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
+int node_reclaim(struct pglist_data *pgdat, gfp_t gfp_mask, unsigned int order)
 {
-	int node_id;
 	int ret;
 
 	/*
-	 * Zone reclaim reclaims unmapped file backed pages and
+	 * Node reclaim reclaims unmapped file backed pages and
 	 * slab pages if we are over the defined limits.
 	 *
 	 * A small portion of unmapped file backed pages is needed for
 	 * file I/O otherwise pages read by file I/O will be immediately
-	 * thrown out if the zone is overallocated. So we do not reclaim
-	 * if less than a specified percentage of the zone is used by
+	 * thrown out if the node is overallocated. So we do not reclaim
+	 * if less than a specified percentage of the node is used by
 	 * unmapped file backed pages.
 	 */
-	if (zone_pagecache_reclaimable(zone) <= zone->min_unmapped_pages &&
-	    zone_page_state(zone, NR_SLAB_RECLAIMABLE) <= zone->min_slab_pages)
-		return ZONE_RECLAIM_FULL;
+	if (node_pagecache_reclaimable(pgdat) <= pgdat->min_unmapped_pages &&
+	    sum_zone_node_page_state(pgdat->node_id, NR_SLAB_RECLAIMABLE) <= pgdat->min_slab_pages)
+		return NODE_RECLAIM_FULL;
 
-	if (!pgdat_reclaimable(zone->zone_pgdat))
-		return ZONE_RECLAIM_FULL;
+	if (!pgdat_reclaimable(pgdat))
+		return NODE_RECLAIM_FULL;
 
 	/*
 	 * Do not scan if the allocation should not be delayed.
 	 */
 	if (!(gfp_mask & __GFP_WAIT) || (current->flags & PF_MEMALLOC))
-		return ZONE_RECLAIM_NOSCAN;
+		return NODE_RECLAIM_NOSCAN;
 
 	/*
-	 * Only run zone reclaim on the local zone or on zones that do not
+	 * Only run node reclaim on the local node or on nodes that do not
 	 * have associated processors. This will favor the local processor
 	 * over remote processors and spread off node memory allocations
 	 * as wide as possible.
 	 */
-	node_id = zone_to_nid(zone);
-	if (node_state(node_id, N_CPU) && node_id != numa_node_id())
-		return ZONE_RECLAIM_NOSCAN;
+	if (node_state(pgdat->node_id, N_CPU) && pgdat->node_id != numa_node_id())
+		return NODE_RECLAIM_NOSCAN;
 
-	if (test_and_set_bit(ZONE_RECLAIM_LOCKED, &zone->flags))
-		return ZONE_RECLAIM_NOSCAN;
+	if (test_and_set_bit(PGDAT_RECLAIM_LOCKED, &pgdat->flags))
+		return NODE_RECLAIM_NOSCAN;
 
-	ret = __zone_reclaim(zone, gfp_mask, order);
-	clear_bit(ZONE_RECLAIM_LOCKED, &zone->flags);
+	ret = __node_reclaim(pgdat, gfp_mask, order);
+	clear_bit(PGDAT_RECLAIM_LOCKED, &pgdat->flags);
 
 	if (!ret)
 		count_vm_event(PGSCAN_ZONE_RECLAIM_FAILED);
-- 
2.3.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ