From: Minchan Kim <minchan@xxxxxxxxxx> If block device supports rw_page operation, it doesn't submit bio so annotation in submit_bio for refault stall doesn't work. It happens with zram in android, especially swap read path which could consume CPU cycle for decompress. Annotate bdev_read_page() to account the synchronous IO overhead to prevent underreport memory pressure. Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Signed-off-by: Minchan Kim <minchan@xxxxxxxxxx> --- fs/block_dev.c | 13 +++++++++++++ mm/memory.c | 1 + 2 files changed, 14 insertions(+) diff --git a/fs/block_dev.c b/fs/block_dev.c index 9c073dbdc1b0..82ca28eb9a57 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -26,6 +26,7 @@ #include <linux/writeback.h> #include <linux/mpage.h> #include <linux/mount.h> +#include <linux/psi.h> #include <linux/pseudo_fs.h> #include <linux/uio.h> #include <linux/namei.h> @@ -701,6 +702,8 @@ int bdev_read_page(struct block_device *bdev, sector_t sector, { const struct block_device_operations *ops = bdev->bd_disk->fops; int result = -EOPNOTSUPP; + unsigned long pflags; + bool workingset_read; if (!ops->rw_page || bdev_get_integrity(bdev)) return result; @@ -708,9 +711,19 @@ int bdev_read_page(struct block_device *bdev, sector_t sector, result = blk_queue_enter(bdev->bd_queue, 0); if (result) return result; + + workingset_read = PageWorkingset(page); + if (workingset_read) + psi_memstall_enter(&pflags); + result = ops->rw_page(bdev, sector + get_start_sect(bdev), page, REQ_OP_READ); + + if (workingset_read) + psi_memstall_leave(&pflags); + blk_queue_exit(bdev->bd_queue); + return result; } EXPORT_SYMBOL_GPL(bdev_read_page); diff --git a/mm/memory.c b/mm/memory.c index 06935826d71e..6357d5a0a2a5 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2801,6 +2801,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) if (page) { __SetPageLocked(page); __SetPageSwapBacked(page); + SetPageWorkingset(page); set_page_private(page, entry.val); lru_cache_add_anon(page); swap_readpage(page, true); -- 2.23.0.581.g78d2f28ef7-goog