[PATCH v4 02/10] Change isolate mode from #define to bitwise type

From: Minchan Kim
Date: Mon Jul 04 2011 - 10:05:24 EST


This patch changes ISOLATE_XXX macro with bitwise isolate_mode_t type.
Normally, macro isn't recommended as it's type-unsafe and making debugging harder
as symbol cannot be passed throught to the debugger.

Quote from Johannes
" Hmm, it would probably be cleaner to fully convert the isolation mode
into independent flags. INACTIVE, ACTIVE, BOTH is currently a
tri-state among flags, which is a bit ugly."

This patch moves isolate mode from swap.h to mmzone.h by memcontrol.h

Changelog since V3
o use isolate_mode_t bitwise type - suggested by Mel
o fix trace-vmscan-postprocess.pl - pointed out by Mel

Changelog since V2
o Remove ISOLATE_BOTH - suggested by Johannes Weiner

Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx>
Cc: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxx>
Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Signed-off-by: Minchan Kim <minchan.kim@xxxxxxxxx>
---
.../trace/postprocess/trace-vmscan-postprocess.pl | 8 ++--
include/linux/memcontrol.h | 3 +-
include/linux/mmzone.h | 8 ++++
include/linux/swap.h | 7 +---
include/trace/events/vmscan.h | 8 ++--
mm/compaction.c | 3 +-
mm/memcontrol.c | 3 +-
mm/vmscan.c | 37 +++++++++++---------
8 files changed, 43 insertions(+), 34 deletions(-)

diff --git a/Documentation/trace/postprocess/trace-vmscan-postprocess.pl b/Documentation/trace/postprocess/trace-vmscan-postprocess.pl
index 12cecc8..4a37c47 100644
--- a/Documentation/trace/postprocess/trace-vmscan-postprocess.pl
+++ b/Documentation/trace/postprocess/trace-vmscan-postprocess.pl
@@ -379,10 +379,10 @@ EVENT_PROCESS:

# To closer match vmstat scanning statistics, only count isolate_both
# and isolate_inactive as scanning. isolate_active is rotation
- # isolate_inactive == 0
- # isolate_active == 1
- # isolate_both == 2
- if ($isolate_mode != 1) {
+ # isolate_inactive == 1
+ # isolate_active == 2
+ # isolate_both == 3
+ if ($isolate_mode != 2) {
$perprocesspid{$process_pid}->{HIGH_NR_SCANNED} += $nr_scanned;
}
$perprocesspid{$process_pid}->{HIGH_NR_CONTIG_DIRTY} += $nr_contig_dirty;
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 970f32c..815d16e 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -35,7 +35,8 @@ enum mem_cgroup_page_stat_item {
extern unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan,
struct list_head *dst,
unsigned long *scanned, int order,
- int mode, struct zone *z,
+ isolate_mode_t mode,
+ struct zone *z,
struct mem_cgroup *mem_cont,
int active, int file);

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 795ec6c..0efdd6e 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -158,6 +158,14 @@ static inline int is_unevictable_lru(enum lru_list l)
return (l == LRU_UNEVICTABLE);
}

+/* Isolate inactive pages */
+#define ISOLATE_INACTIVE ((__force fmode_t)0x1)
+/* Isolate active pages */
+#define ISOLATE_ACTIVE ((__force fmode_t)0x2)
+
+/* LRU Isolation modes. */
+typedef unsigned __bitwise__ isolate_mode_t;
+
enum zone_watermarks {
WMARK_MIN,
WMARK_LOW,
diff --git a/include/linux/swap.h b/include/linux/swap.h
index 808690a..03727bf 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -245,11 +245,6 @@ static inline void lru_cache_add_file(struct page *page)
__lru_cache_add(page, LRU_INACTIVE_FILE);
}

-/* LRU Isolation modes. */
-#define ISOLATE_INACTIVE 0 /* Isolate inactive pages. */
-#define ISOLATE_ACTIVE 1 /* Isolate active pages. */
-#define ISOLATE_BOTH 2 /* Isolate both active and inactive pages. */
-
/* linux/mm/vmscan.c */
extern unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
gfp_t gfp_mask, nodemask_t *mask);
@@ -261,7 +256,7 @@ extern unsigned long mem_cgroup_shrink_node_zone(struct mem_cgroup *mem,
unsigned int swappiness,
struct zone *zone,
unsigned long *nr_scanned);
-extern int __isolate_lru_page(struct page *page, int mode, int file);
+extern int __isolate_lru_page(struct page *page, isolate_mode_t mode, int file);
extern unsigned long shrink_all_memory(unsigned long nr_pages);
extern int vm_swappiness;
extern int remove_mapping(struct address_space *mapping, struct page *page);
diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h
index b2c33bd..04203b8 100644
--- a/include/trace/events/vmscan.h
+++ b/include/trace/events/vmscan.h
@@ -189,7 +189,7 @@ DECLARE_EVENT_CLASS(mm_vmscan_lru_isolate_template,
unsigned long nr_lumpy_taken,
unsigned long nr_lumpy_dirty,
unsigned long nr_lumpy_failed,
- int isolate_mode),
+ isolate_mode_t isolate_mode),

TP_ARGS(order, nr_requested, nr_scanned, nr_taken, nr_lumpy_taken, nr_lumpy_dirty, nr_lumpy_failed, isolate_mode),

@@ -201,7 +201,7 @@ DECLARE_EVENT_CLASS(mm_vmscan_lru_isolate_template,
__field(unsigned long, nr_lumpy_taken)
__field(unsigned long, nr_lumpy_dirty)
__field(unsigned long, nr_lumpy_failed)
- __field(int, isolate_mode)
+ __field(isolate_mode_t, isolate_mode)
),

TP_fast_assign(
@@ -235,7 +235,7 @@ DEFINE_EVENT(mm_vmscan_lru_isolate_template, mm_vmscan_lru_isolate,
unsigned long nr_lumpy_taken,
unsigned long nr_lumpy_dirty,
unsigned long nr_lumpy_failed,
- int isolate_mode),
+ isolate_mode_t isolate_mode),

TP_ARGS(order, nr_requested, nr_scanned, nr_taken, nr_lumpy_taken, nr_lumpy_dirty, nr_lumpy_failed, isolate_mode)

@@ -250,7 +250,7 @@ DEFINE_EVENT(mm_vmscan_lru_isolate_template, mm_vmscan_memcg_isolate,
unsigned long nr_lumpy_taken,
unsigned long nr_lumpy_dirty,
unsigned long nr_lumpy_failed,
- int isolate_mode),
+ isolate_mode_t isolate_mode),

TP_ARGS(order, nr_requested, nr_scanned, nr_taken, nr_lumpy_taken, nr_lumpy_dirty, nr_lumpy_failed, isolate_mode)

diff --git a/mm/compaction.c b/mm/compaction.c
index b2977a5..47f717f 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -349,7 +349,8 @@ static isolate_migrate_t isolate_migratepages(struct zone *zone,
}

/* Try isolate the page */
- if (__isolate_lru_page(page, ISOLATE_BOTH, 0) != 0)
+ if (__isolate_lru_page(page,
+ ISOLATE_ACTIVE|ISOLATE_INACTIVE, 0) != 0)
continue;

VM_BUG_ON(PageTransCompound(page));
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index aaff06f..5b544f0 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1251,7 +1251,8 @@ mem_cgroup_get_reclaim_stat_from_page(struct page *page)
unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan,
struct list_head *dst,
unsigned long *scanned, int order,
- int mode, struct zone *z,
+ isolate_mode_t mode,
+ struct zone *z,
struct mem_cgroup *mem_cont,
int active, int file)
{
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 5ed24b9..1736ecf 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -972,23 +972,27 @@ keep_lumpy:
*
* returns 0 on success, -ve errno on failure.
*/
-int __isolate_lru_page(struct page *page, int mode, int file)
+int __isolate_lru_page(struct page *page, isolate_mode_t mode, int file)
{
+ bool all_lru_mode;
int ret = -EINVAL;

/* Only take pages on the LRU. */
if (!PageLRU(page))
return ret;

+ all_lru_mode = (mode & (ISOLATE_ACTIVE|ISOLATE_INACTIVE)) ==
+ (ISOLATE_ACTIVE|ISOLATE_INACTIVE);
+
/*
* When checking the active state, we need to be sure we are
* dealing with comparible boolean values. Take the logical not
* of each.
*/
- if (mode != ISOLATE_BOTH && (!PageActive(page) != !mode))
+ if (!all_lru_mode && !PageActive(page) != !(mode & ISOLATE_ACTIVE))
return ret;

- if (mode != ISOLATE_BOTH && page_is_file_cache(page) != file)
+ if (!all_lru_mode && !!page_is_file_cache(page) != file)
return ret;

/*
@@ -1036,7 +1040,8 @@ int __isolate_lru_page(struct page *page, int mode, int file)
*/
static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
struct list_head *src, struct list_head *dst,
- unsigned long *scanned, int order, int mode, int file)
+ unsigned long *scanned, int order, isolate_mode_t mode,
+ int file)
{
unsigned long nr_taken = 0;
unsigned long nr_lumpy_taken = 0;
@@ -1161,8 +1166,8 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
static unsigned long isolate_pages_global(unsigned long nr,
struct list_head *dst,
unsigned long *scanned, int order,
- int mode, struct zone *z,
- int active, int file)
+ isolate_mode_t mode,
+ struct zone *z, int active, int file)
{
int lru = LRU_BASE;
if (active)
@@ -1408,6 +1413,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone,
unsigned long nr_taken;
unsigned long nr_anon;
unsigned long nr_file;
+ isolate_mode_t reclaim_mode = ISOLATE_INACTIVE;

while (unlikely(too_many_isolated(zone, file, sc))) {
congestion_wait(BLK_RW_ASYNC, HZ/10);
@@ -1418,15 +1424,15 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone,
}

set_reclaim_mode(priority, sc, false);
+ if (sc->reclaim_mode & RECLAIM_MODE_LUMPYRECLAIM)
+ reclaim_mode |= ISOLATE_ACTIVE;
+
lru_add_drain();
spin_lock_irq(&zone->lru_lock);

if (scanning_global_lru(sc)) {
- nr_taken = isolate_pages_global(nr_to_scan,
- &page_list, &nr_scanned, sc->order,
- sc->reclaim_mode & RECLAIM_MODE_LUMPYRECLAIM ?
- ISOLATE_BOTH : ISOLATE_INACTIVE,
- zone, 0, file);
+ nr_taken = isolate_pages_global(nr_to_scan, &page_list,
+ &nr_scanned, sc->order, reclaim_mode, zone, 0, file);
zone->pages_scanned += nr_scanned;
if (current_is_kswapd())
__count_zone_vm_events(PGSCAN_KSWAPD, zone,
@@ -1435,12 +1441,9 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone,
__count_zone_vm_events(PGSCAN_DIRECT, zone,
nr_scanned);
} else {
- nr_taken = mem_cgroup_isolate_pages(nr_to_scan,
- &page_list, &nr_scanned, sc->order,
- sc->reclaim_mode & RECLAIM_MODE_LUMPYRECLAIM ?
- ISOLATE_BOTH : ISOLATE_INACTIVE,
- zone, sc->mem_cgroup,
- 0, file);
+ nr_taken = mem_cgroup_isolate_pages(nr_to_scan, &page_list,
+ &nr_scanned, sc->order, reclaim_mode, zone,
+ sc->mem_cgroup, 0, file);
/*
* mem_cgroup_isolate_pages() keeps track of
* scanned pages on its own.
--
1.7.4.1

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