Commit 6e1fa555 authored by Kanchana P Sridhar's avatar Kanchana P Sridhar Committed by Andrew Morton
Browse files

mm: zswap: modify zswap_stored_pages to be atomic_long_t 

For zswap_store() to support large folios, we need to be able to do a
batch update of zswap_stored_pages upon successful store of all pages in
the folio.  For this, we need to add folio_nr_pages(), which returns a
long, to zswap_stored_pages.

Link: https://lkml.kernel.org/r/20241001053222.6944-6-kanchana.p.sridhar@intel.com


Signed-off-by: default avatarKanchana P Sridhar <kanchana.p.sridhar@intel.com>
Acked-by: default avatarYosry Ahmed <yosryahmed@google.com>
Acked-by: default avatarJohannes Weiner <hannes@cmpxchg.org>
Reviewed-by: default avatarNhat Pham <nphamcs@gmail.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Usama Arif <usamaarif642@gmail.com>
Cc: Wajdi Feghali <wajdi.k.feghali@intel.com>
Cc: "Zou, Nanhai" <nanhai.zou@intel.com>
Cc: Barry Song <21cnbao@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 0201c054

fs/proc/meminfo.c

+1 −1
Original line number Diff line number Diff line
@@ -91,7 +91,7 @@ static int meminfo_proc_show(struct seq_file *m, void *v) 
#ifdef CONFIG_ZSWAP

	show_val_kb(m, "Zswap:          ", zswap_total_pages());

	seq_printf(m,  "Zswapped:       %8lu kB\n",

		   (unsigned long)atomic_read(&zswap_stored_pages) <<

		   (unsigned long)atomic_long_read(&zswap_stored_pages) <<

		   (PAGE_SHIFT - 10));

#endif

	show_val_kb(m, "Dirty:          ",

include/linux/zswap.h

+1 −1
Original line number Diff line number Diff line
@@ -7,7 +7,7 @@ 


struct lruvec;



extern atomic_t zswap_stored_pages;

extern atomic_long_t zswap_stored_pages;



#ifdef CONFIG_ZSWAP

mm/zswap.c

+13 −6
Original line number Diff line number Diff line
@@ -43,7 +43,7 @@ 
* statistics

**********************************/

/* The number of compressed pages currently stored in zswap */

atomic_t zswap_stored_pages = ATOMIC_INIT(0);

atomic_long_t zswap_stored_pages = ATOMIC_INIT(0);



/*

 * The statistics below are not protected from concurrent access for
@@ -802,7 +802,7 @@ static void zswap_entry_free(struct zswap_entry *entry) 
		obj_cgroup_put(entry->objcg);

	}

	zswap_entry_cache_free(entry);

	atomic_dec(&zswap_stored_pages);

	atomic_long_dec(&zswap_stored_pages);

}



/*********************************
@@ -1233,7 +1233,7 @@ static unsigned long zswap_shrinker_count(struct shrinker *shrinker, 
		nr_stored = memcg_page_state(memcg, MEMCG_ZSWAPPED);

	} else {

		nr_backing = zswap_total_pages();

		nr_stored = atomic_read(&zswap_stored_pages);

		nr_stored = atomic_long_read(&zswap_stored_pages);

	}



	if (!nr_stored)
@@ -1502,7 +1502,7 @@ bool zswap_store(struct folio *folio) 
	}



	/* update stats */

	atomic_inc(&zswap_stored_pages);

	atomic_long_inc(&zswap_stored_pages);

	count_vm_event(ZSWPOUT);



	return true;
@@ -1654,6 +1654,13 @@ static int debugfs_get_total_size(void *data, u64 *val) 
}

DEFINE_DEBUGFS_ATTRIBUTE(total_size_fops, debugfs_get_total_size, NULL, "%llu\n");



static int debugfs_get_stored_pages(void *data, u64 *val)

{

	*val = atomic_long_read(&zswap_stored_pages);

	return 0;

}

DEFINE_DEBUGFS_ATTRIBUTE(stored_pages_fops, debugfs_get_stored_pages, NULL, "%llu\n");



static int zswap_debugfs_init(void)

{

	if (!debugfs_initialized())
@@ -1677,8 +1684,8 @@ static int zswap_debugfs_init(void) 
			   zswap_debugfs_root, &zswap_written_back_pages);

	debugfs_create_file("pool_total_size", 0444,

			    zswap_debugfs_root, NULL, &total_size_fops);

	debugfs_create_atomic_t("stored_pages", 0444,

				zswap_debugfs_root, &zswap_stored_pages);

	debugfs_create_file("stored_pages", 0444,

			    zswap_debugfs_root, NULL, &stored_pages_fops);



	return 0;

}