CONFIG_LOCKDEP_PAGELOCK is keeping data, with which lockdep can check
and detect deadlock by page lock, e.g. lockdep_map and cross_lock in
struct page. But move it to page_ext since it's a debug feature so it's
preferred to keep it in struct page_ext than struct page.
Signed-off-by: Byungchul Park <byungchul.park@xxxxxxx>
---
include/linux/mm_types.h | 5 ----
include/linux/page-flags.h | 19 ++++++++++--
include/linux/page_ext.h | 5 ++++
include/linux/pagemap.h | 28 +++++++++++++++---
lib/Kconfig.debug | 1 +
mm/filemap.c | 72 ++++++++++++++++++++++++++++++++++++++++++++++
mm/page_alloc.c | 3 --
mm/page_ext.c | 4 +++
8 files changed, 122 insertions(+), 15 deletions(-)
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 87db0ac..6558e12 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -224,11 +224,6 @@ struct page {
#ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
int _last_cpupid;
#endif
-
-#ifdef CONFIG_LOCKDEP_PAGELOCK
- struct lockdep_map map;
- struct cross_lock xlock;
-#endif
}
/*
* The struct page can be forced to be double word aligned so that atomic ops
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index e28f232..9f677ff 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -352,28 +352,41 @@ PAGEFLAG(Idle, idle, PF_ANY)
#ifdef CONFIG_LOCKDEP_PAGELOCK
#include <linux/lockdep.h>
+#include <linux/page_ext.h>
TESTPAGEFLAG(Locked, locked, PF_NO_TAIL)
static __always_inline void __SetPageLocked(struct page *page)
{
+ struct page_ext *e;
+
__set_bit(PG_locked, &PF_NO_TAIL(page, 1)->flags);
page = compound_head(page);
- lock_acquire_exclusive(&page->map, 0, 1, NULL, _RET_IP_);
+ e = lookup_page_ext(page);
+ if (unlikely(!e))
+ return;
+
+ lock_acquire_exclusive(&e->map, 0, 1, NULL, _RET_IP_);
}
static __always_inline void __ClearPageLocked(struct page *page)
{
+ struct page_ext *e;
+
__clear_bit(PG_locked, &PF_NO_TAIL(page, 1)->flags);
page = compound_head(page);
+ e = lookup_page_ext(page);
+ if (unlikely(!e))
+ return;
+
/*
* lock_commit_crosslock() is necessary for crosslock
* when the lock is released, before lock_release().
*/
- lock_commit_crosslock(&page->map);
- lock_release(&page->map, 0, _RET_IP_);
+ lock_commit_crosslock(&e->map);
+ lock_release(&e->map, 0, _RET_IP_);
}
#else
__PAGEFLAG(Locked, locked, PF_NO_TAIL)
diff --git a/include/linux/page_ext.h b/include/linux/page_ext.h
index e1fe7cf..f84e9be 100644
--- a/include/linux/page_ext.h
+++ b/include/linux/page_ext.h
@@ -48,6 +48,11 @@ struct page_ext {
int last_migrate_reason;
unsigned long trace_entries[8];
#endif
+
+#ifdef CONFIG_LOCKDEP_PAGELOCK
+ struct lockdep_map map;
+ struct cross_lock xlock;
+#endif
};
extern void pgdat_page_ext_init(struct pglist_data *pgdat);
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index dbe7adf..79174ad 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -16,6 +16,7 @@
#include <linux/hugetlb_inline.h>
#ifdef CONFIG_LOCKDEP_PAGELOCK
#include <linux/lockdep.h>
+#include <linux/page_ext.h>
#endif
/*
@@ -417,28 +418,47 @@ static inline pgoff_t linear_page_index(struct vm_area_struct *vma,
}
#ifdef CONFIG_LOCKDEP_PAGELOCK
+extern struct page_ext_operations lockdep_pagelock_ops;
+
#define lock_page_init(p) \
do { \
static struct lock_class_key __key; \
- lockdep_init_map_crosslock(&(p)->map, &(p)->xlock, \
+ struct page_ext *e = lookup_page_ext(p); \
+ \
+ if (unlikely(!e)) \
+ break; \
+ \
+ lockdep_init_map_crosslock(&(e)->map, &(e)->xlock, \
"(PG_locked)" #p, &__key, 0); \
} while (0)
static inline void lock_page_acquire(struct page *page, int try)
{
+ struct page_ext *e;
+
page = compound_head(page);
- lock_acquire_exclusive(&page->map, 0, try, NULL, _RET_IP_);
+ e = lookup_page_ext(page);
+ if (unlikely(!e))
+ return;
+
+ lock_acquire_exclusive(&e->map, 0, try, NULL, _RET_IP_);
}
static inline void lock_page_release(struct page *page)
{
+ struct page_ext *e;
+
page = compound_head(page);
+ e = lookup_page_ext(page);
+ if (unlikely(!e))
+ return;
+
/*
* lock_commit_crosslock() is necessary for crosslock
* when the lock is released, before lock_release().
*/
- lock_commit_crosslock(&page->map);
- lock_release(&page->map, 0, _RET_IP_);
+ lock_commit_crosslock(&e->map);
+ lock_release(&e->map, 0, _RET_IP_);
}
#else
static inline void lock_page_init(struct page *page) {}
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 1926435..9c6dc15 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1051,6 +1051,7 @@ config LOCKDEP_COMPLETE
config LOCKDEP_PAGELOCK
bool "Lock debugging: allow PG_locked lock to use deadlock detector"
select LOCKDEP_CROSSRELEASE
+ select PAGE_EXTENSION
default n
help
PG_locked lock is a kind of crosslock. Using crossrelease feature,
diff --git a/mm/filemap.c b/mm/filemap.c
index e1f60fd..a6a52a4 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -35,6 +35,9 @@
#include <linux/memcontrol.h>
#include <linux/cleancache.h>
#include <linux/rmap.h>
+#ifdef CONFIG_LOCKDEP_PAGELOCK
+#include <linux/page_ext.h>
+#endif
#include "internal.h"
#define CREATE_TRACE_POINTS
@@ -955,6 +958,75 @@ int __lock_page_or_retry(struct page *page, struct mm_struct *mm,
}
}
+#ifdef CONFIG_LOCKDEP_PAGELOCK
+static bool need_lockdep_pagelock(void) { return true; }
+
+static void init_pages_in_zone(pg_data_t *pgdat, struct zone *zone)
+{
+ struct page *page;
+ struct page_ext *page_ext;
+ unsigned long pfn = zone->zone_start_pfn;
+ unsigned long end_pfn = pfn + zone->spanned_pages;
+ unsigned long count = 0;
+
+ for (; pfn < end_pfn; pfn++) {
+ if (!pfn_valid(pfn)) {
+ pfn = ALIGN(pfn + 1, MAX_ORDER_NR_PAGES);
+ continue;
+ }
+
+ if (!pfn_valid_within(pfn))
+ continue;
+
+ page = pfn_to_page(pfn);
+
+ if (page_zone(page) != zone)
+ continue;
+
+ if (PageReserved(page))
+ continue;
+
+ page_ext = lookup_page_ext(page);
+ if (unlikely(!page_ext))
+ continue;
+
+ lock_page_init(page);
+ count++;
+ }
+
+ pr_info("Node %d, zone %8s: lockdep pagelock found early allocated %lu pages\n",
+ pgdat->node_id, zone->name, count);
+}
+
+static void init_zones_in_node(pg_data_t *pgdat)
+{
+ struct zone *zone;
+ struct zone *node_zones = pgdat->node_zones;
+ unsigned long flags;
+
+ for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; ++zone) {
+ if (!populated_zone(zone))
+ continue;
+
+ spin_lock_irqsave(&zone->lock, flags);
+ init_pages_in_zone(pgdat, zone);
+ spin_unlock_irqrestore(&zone->lock, flags);
+ }
+}
+
+static void init_lockdep_pagelock(void)
+{
+ pg_data_t *pgdat;
+ for_each_online_pgdat(pgdat)
+ init_zones_in_node(pgdat);
+}
+
+struct page_ext_operations lockdep_pagelock_ops = {
+ .need = need_lockdep_pagelock,
+ .init = init_lockdep_pagelock,
+};
+#endif
+
/**
* page_cache_next_hole - find the next hole (not-present entry)
* @mapping: mapping
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 0adc46c..8b3e134 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5225,9 +5225,6 @@ not_early:
} else {
__init_single_pfn(pfn, zone, nid);
}
-#ifdef CONFIG_LOCKDEP_PAGELOCK
- lock_page_init(pfn_to_page(pfn));
-#endif
}
}
diff --git a/mm/page_ext.c b/mm/page_ext.c
index 44a4c02..54f7027 100644
--- a/mm/page_ext.c
+++ b/mm/page_ext.c
@@ -7,6 +7,7 @@
#include <linux/kmemleak.h>
#include <linux/page_owner.h>
#include <linux/page_idle.h>
+#include <linux/pagemap.h>
/*
* struct page extension
@@ -63,6 +64,9 @@ static struct page_ext_operations *page_ext_ops[] = {
#if defined(CONFIG_IDLE_PAGE_TRACKING) && !defined(CONFIG_64BIT)
&page_idle_ops,
#endif
+#ifdef CONFIG_LOCKDEP_PAGELOCK
+ &lockdep_pagelock_ops,
+#endif
};
static unsigned long total_usage;
--
1.9.1
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>