diff options
Diffstat (limited to 'mm/page_io.c')
| -rw-r--r-- | mm/page_io.c | 21 |
1 files changed, 16 insertions, 5 deletions
diff --git a/mm/page_io.c b/mm/page_io.c index 24ee600f9131..3a198deb8bb1 100644 --- a/mm/page_io.c +++ b/mm/page_io.c @@ -22,6 +22,7 @@ #include <linux/writeback.h> #include <linux/frontswap.h> #include <linux/blkdev.h> +#include <linux/psi.h> #include <linux/uio.h> #include <linux/sched/task.h> #include <asm/pgtable.h> @@ -73,6 +74,7 @@ static void swap_slot_free_notify(struct page *page) { struct swap_info_struct *sis; struct gendisk *disk; + swp_entry_t entry; /* * There is no guarantee that the page is in swap cache - the software @@ -104,11 +106,10 @@ static void swap_slot_free_notify(struct page *page) * we again wish to reclaim it. */ disk = sis->bdev->bd_disk; - if (disk->fops->swap_slot_free_notify) { - swp_entry_t entry; + entry.val = page_private(page); + if (disk->fops->swap_slot_free_notify && __swap_count(entry) == 1) { unsigned long offset; - entry.val = page_private(page); offset = swp_offset(entry); SetPageDirty(page); @@ -354,10 +355,19 @@ int swap_readpage(struct page *page, bool synchronous) struct swap_info_struct *sis = page_swap_info(page); blk_qc_t qc; struct gendisk *disk; + unsigned long pflags; VM_BUG_ON_PAGE(!PageSwapCache(page) && !synchronous, page); VM_BUG_ON_PAGE(!PageLocked(page), page); VM_BUG_ON_PAGE(PageUptodate(page), page); + + /* + * Count submission time as memory stall. When the device is congested, + * or the submitting cgroup IO-throttled, submission can be a + * significant part of overall IO time. + */ + psi_memstall_enter(&pflags); + if (frontswap_load(page) == 0) { SetPageUptodate(page); unlock_page(page); @@ -371,7 +381,7 @@ int swap_readpage(struct page *page, bool synchronous) ret = mapping->a_ops->readpage(swap_file, page); if (!ret) count_vm_event(PSWPIN); - return ret; + goto out; } ret = bdev_read_page(sis->bdev, swap_page_sector(page), page); @@ -382,7 +392,7 @@ int swap_readpage(struct page *page, bool synchronous) } count_vm_event(PSWPIN); - return 0; + goto out; } ret = 0; @@ -418,6 +428,7 @@ int swap_readpage(struct page *page, bool synchronous) bio_put(bio); out: + psi_memstall_leave(&pflags); return ret; } |