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@xxxxxxx>
---
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
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