From 7d3f3938236b4bb878214e6791e76fd8409bdeee Mon Sep 17 00:00:00 2001 From: Sergey Senozhatsky Date: Tue, 8 Sep 2015 15:04:35 -0700 Subject: zsmalloc/zram: introduce zs_pool_stats api `zs_compact_control' accounts the number of migrated objects but it has a limited lifespan -- we lose it as soon as zs_compaction() returns back to zram. It worked fine, because (a) zram had it's own counter of migrated objects and (b) only zram could trigger compaction. However, this does not work for automatic pool compaction (not issued by zram). To account objects migrated during auto-compaction (issued by the shrinker) we need to store this number in zs_pool. Define a new `struct zs_pool_stats' structure to keep zs_pool's stats there. It provides only `num_migrated', as of this writing, but it surely can be extended. A new zsmalloc zs_pool_stats() symbol exports zs_pool's stats back to caller. Use zs_pool_stats() in zram and remove `num_migrated' from zram_stats. Signed-off-by: Sergey Senozhatsky Suggested-by: Minchan Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/block/zram/zram_drv.c | 15 +++++++++------ drivers/block/zram/zram_drv.h | 1 - 2 files changed, 9 insertions(+), 7 deletions(-) (limited to 'drivers/block') diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index 9c01f5bfa33f..bcde5c321090 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -388,7 +388,6 @@ static ssize_t comp_algorithm_store(struct device *dev, static ssize_t compact_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { - unsigned long nr_migrated; struct zram *zram = dev_to_zram(dev); struct zram_meta *meta; @@ -399,8 +398,7 @@ static ssize_t compact_store(struct device *dev, } meta = zram->meta; - nr_migrated = zs_compact(meta->mem_pool); - atomic64_add(nr_migrated, &zram->stats.num_migrated); + zs_compact(meta->mem_pool); up_read(&zram->init_lock); return len; @@ -428,26 +426,31 @@ static ssize_t mm_stat_show(struct device *dev, struct device_attribute *attr, char *buf) { struct zram *zram = dev_to_zram(dev); + struct zs_pool_stats pool_stats; u64 orig_size, mem_used = 0; long max_used; ssize_t ret; + memset(&pool_stats, 0x00, sizeof(struct zs_pool_stats)); + down_read(&zram->init_lock); - if (init_done(zram)) + if (init_done(zram)) { mem_used = zs_get_total_pages(zram->meta->mem_pool); + zs_pool_stats(zram->meta->mem_pool, &pool_stats); + } orig_size = atomic64_read(&zram->stats.pages_stored); max_used = atomic_long_read(&zram->stats.max_used_pages); ret = scnprintf(buf, PAGE_SIZE, - "%8llu %8llu %8llu %8lu %8ld %8llu %8llu\n", + "%8llu %8llu %8llu %8lu %8ld %8llu %8lu\n", orig_size << PAGE_SHIFT, (u64)atomic64_read(&zram->stats.compr_data_size), mem_used << PAGE_SHIFT, zram->limit_pages << PAGE_SHIFT, max_used << PAGE_SHIFT, (u64)atomic64_read(&zram->stats.zero_pages), - (u64)atomic64_read(&zram->stats.num_migrated)); + pool_stats.num_migrated); up_read(&zram->init_lock); return ret; diff --git a/drivers/block/zram/zram_drv.h b/drivers/block/zram/zram_drv.h index 6dbe2df506bf..8e92339686d7 100644 --- a/drivers/block/zram/zram_drv.h +++ b/drivers/block/zram/zram_drv.h @@ -78,7 +78,6 @@ struct zram_stats { atomic64_t compr_data_size; /* compressed size of pages stored */ atomic64_t num_reads; /* failed + successful */ atomic64_t num_writes; /* --do-- */ - atomic64_t num_migrated; /* no. of migrated object */ atomic64_t failed_reads; /* can happen when memory is too low */ atomic64_t failed_writes; /* can happen when memory is too low */ atomic64_t invalid_io; /* non-page-aligned I/O requests */ -- cgit v1.2.3