diff options
| -rw-r--r-- | include/linux/frontswap.h | 2 | ||||
| -rw-r--r-- | mm/frontswap.c | 23 |
2 files changed, 24 insertions, 1 deletions
diff --git a/include/linux/frontswap.h b/include/linux/frontswap.h index 0e4e2eec5c1..30442547b9e 100644 --- a/include/linux/frontswap.h +++ b/include/linux/frontswap.h @@ -19,6 +19,8 @@ extern struct frontswap_ops extern void frontswap_shrink(unsigned long); extern unsigned long frontswap_curr_pages(void); extern void frontswap_writethrough(bool); +#define FRONTSWAP_HAS_EXCLUSIVE_GETS +extern void frontswap_tmem_exclusive_gets(bool); extern void __frontswap_init(unsigned type); extern int __frontswap_store(struct page *page); diff --git a/mm/frontswap.c b/mm/frontswap.c index 0547a35f798..2890e67d602 100644 --- a/mm/frontswap.c +++ b/mm/frontswap.c @@ -44,6 +44,13 @@ EXPORT_SYMBOL(frontswap_enabled); */ static bool frontswap_writethrough_enabled __read_mostly; +/* + * If enabled, the underlying tmem implementation is capable of doing + * exclusive gets, so frontswap_load, on a successful tmem_get must + * mark the page as no longer in frontswap AND mark it dirty. + */ +static bool frontswap_tmem_exclusive_gets_enabled __read_mostly; + #ifdef CONFIG_DEBUG_FS /* * Counters available via /sys/kernel/debug/frontswap (if debugfs is @@ -97,6 +104,15 @@ void frontswap_writethrough(bool enable) EXPORT_SYMBOL(frontswap_writethrough); /* + * Enable/disable frontswap exclusive gets (see above). + */ +void frontswap_tmem_exclusive_gets(bool enable) +{ + frontswap_tmem_exclusive_gets_enabled = enable; +} +EXPORT_SYMBOL(frontswap_tmem_exclusive_gets); + +/* * Called when a swap device is swapon'd. */ void __frontswap_init(unsigned type) @@ -174,8 +190,13 @@ int __frontswap_load(struct page *page) BUG_ON(sis == NULL); if (frontswap_test(sis, offset)) ret = frontswap_ops.load(type, offset, page); - if (ret == 0) + if (ret == 0) { inc_frontswap_loads(); + if (frontswap_tmem_exclusive_gets_enabled) { + SetPageDirty(page); + frontswap_clear(sis, offset); + } + } return ret; } EXPORT_SYMBOL(__frontswap_load); |