We are using PAGE_SIZE as the unit to determine if the total len in
async_list has exceeded max_pages, it's not fair for smaller io sizes.
For example, if we are doing 1k-size io streams, we will never exceed
max_pages since len >>= PAGE_SHIFT always gets zero. So use original
bytes to make things fair.
Signed-off-by: Zhengyuan Liu <liuzhengyuan@xxxxxxxxxx>
---
fs/io_uring.c | 17 ++++++++---------
1 file changed, 8 insertions(+), 9 deletions(-)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 7e932c572f26..79272cf1ab83 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -202,7 +202,7 @@ struct async_list {
struct file *file;
off_t io_end;
- size_t io_pages;
+ size_t io_len;
};
struct io_ring_ctx {
@@ -1121,28 +1121,27 @@ static void io_async_list_note(int rw, struct io_kiocb *req, size_t len)
off_t io_end = kiocb->ki_pos + len;
if (filp == async_list->file && kiocb->ki_pos == async_list->io_end) {
- unsigned long max_pages;
+ unsigned long max_pages, max_bytes;
/* Use 8x RA size as a decent limiter for both reads/writes */
max_pages = filp->f_ra.ra_pages;
if (!max_pages)
max_pages = VM_READAHEAD_PAGES;
- max_pages *= 8;
+ max_bytes = (max_pages * 8) << PAGE_SHIFT;
- /* If max pages are exceeded, reset the state */
- len >>= PAGE_SHIFT;
- if (async_list->io_pages + len <= max_pages) {
+ /* If max len are exceeded, reset the state */
+ if (async_list->io_len + len <= max_bytes) {
req->flags |= REQ_F_SEQ_PREV;
- async_list->io_pages += len;
+ async_list->io_len += len;
} else {
io_end = 0;
- async_list->io_pages = 0;
+ async_list->io_len = 0;
}
}
/* New file? Reset state. */
if (async_list->file != filp) {
- async_list->io_pages = 0;
+ async_list->io_len = 0;
async_list->file = filp;
}
async_list->io_end = io_end;
--
2.19.1
