[PATCH v3 1/1] io_uring: optimise sqe-to-req flags translation
From: Pavel Begunkov
Date: Sat Jan 18 2020 - 12:23:32 EST
For each IOSQE_* flag there is a corresponding REQ_F_* flag. And there
is a repetitive pattern of their translation:
e.g. if (sqe->flags & SQE_FLAG*) req->flags |= REQ_F_FLAG*
Use same numeric values/bits for them and copy instead of manual
handling.
Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx>
---
v2: enum to generate bits (Jens Axboe)
v3: don't use BIT() for userspace headers (Jens Axboe)
leave IOSQE_* as defines for compatibility (Jens Axboe)
fs/io_uring.c | 92 ++++++++++++++++++++++++-----------
include/uapi/linux/io_uring.h | 23 +++++++--
2 files changed, 81 insertions(+), 34 deletions(-)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index ed1adeda370e..cf5bad51f752 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -46,6 +46,7 @@
#include <linux/compat.h>
#include <linux/refcount.h>
#include <linux/uio.h>
+#include <linux/bits.h>
#include <linux/sched/signal.h>
#include <linux/fs.h>
@@ -452,6 +453,65 @@ struct io_async_ctx {
};
};
+enum {
+ REQ_F_FIXED_FILE_BIT = IOSQE_FIXED_FILE_BIT,
+ REQ_F_IO_DRAIN_BIT = IOSQE_IO_DRAIN_BIT,
+ REQ_F_LINK_BIT = IOSQE_IO_LINK_BIT,
+ REQ_F_HARDLINK_BIT = IOSQE_IO_HARDLINK_BIT,
+ REQ_F_FORCE_ASYNC_BIT = IOSQE_ASYNC_BIT,
+
+ REQ_F_LINK_NEXT_BIT,
+ REQ_F_FAIL_LINK_BIT,
+ REQ_F_INFLIGHT_BIT,
+ REQ_F_CUR_POS_BIT,
+ REQ_F_NOWAIT_BIT,
+ REQ_F_IOPOLL_COMPLETED_BIT,
+ REQ_F_LINK_TIMEOUT_BIT,
+ REQ_F_TIMEOUT_BIT,
+ REQ_F_ISREG_BIT,
+ REQ_F_MUST_PUNT_BIT,
+ REQ_F_TIMEOUT_NOSEQ_BIT,
+ REQ_F_COMP_LOCKED_BIT,
+};
+
+enum {
+ /* ctx owns file */
+ REQ_F_FIXED_FILE = BIT(REQ_F_FIXED_FILE_BIT),
+ /* drain existing IO first */
+ REQ_F_IO_DRAIN = BIT(REQ_F_IO_DRAIN_BIT),
+ /* linked sqes */
+ REQ_F_LINK = BIT(REQ_F_LINK_BIT),
+ /* doesn't sever on completion < 0 */
+ REQ_F_HARDLINK = BIT(REQ_F_HARDLINK_BIT),
+ /* IOSQE_ASYNC */
+ REQ_F_FORCE_ASYNC = BIT(REQ_F_FORCE_ASYNC_BIT),
+
+ /* already grabbed next link */
+ REQ_F_LINK_NEXT = BIT(REQ_F_LINK_NEXT_BIT),
+ /* fail rest of links */
+ REQ_F_FAIL_LINK = BIT(REQ_F_FAIL_LINK_BIT),
+ /* on inflight list */
+ REQ_F_INFLIGHT = BIT(REQ_F_INFLIGHT_BIT),
+ /* read/write uses file position */
+ REQ_F_CUR_POS = BIT(REQ_F_CUR_POS_BIT),
+ /* must not punt to workers */
+ REQ_F_NOWAIT = BIT(REQ_F_NOWAIT_BIT),
+ /* polled IO has completed */
+ REQ_F_IOPOLL_COMPLETED = BIT(REQ_F_IOPOLL_COMPLETED_BIT),
+ /* has linked timeout */
+ REQ_F_LINK_TIMEOUT = BIT(REQ_F_LINK_TIMEOUT_BIT),
+ /* timeout request */
+ REQ_F_TIMEOUT = BIT(REQ_F_TIMEOUT_BIT),
+ /* regular file */
+ REQ_F_ISREG = BIT(REQ_F_ISREG_BIT),
+ /* must be punted even for NONBLOCK */
+ REQ_F_MUST_PUNT = BIT(REQ_F_MUST_PUNT_BIT),
+ /* no timeout sequence */
+ REQ_F_TIMEOUT_NOSEQ = BIT(REQ_F_TIMEOUT_NOSEQ_BIT),
+ /* completion under lock */
+ REQ_F_COMP_LOCKED = BIT(REQ_F_COMP_LOCKED_BIT),
+};
+
/*
* NOTE! Each of the iocb union members has the file pointer
* as the first entry in their struct definition. So you can
@@ -494,23 +554,6 @@ struct io_kiocb {
struct list_head link_list;
unsigned int flags;
refcount_t refs;
-#define REQ_F_NOWAIT 1 /* must not punt to workers */
-#define REQ_F_IOPOLL_COMPLETED 2 /* polled IO has completed */
-#define REQ_F_FIXED_FILE 4 /* ctx owns file */
-#define REQ_F_LINK_NEXT 8 /* already grabbed next link */
-#define REQ_F_IO_DRAIN 16 /* drain existing IO first */
-#define REQ_F_LINK 64 /* linked sqes */
-#define REQ_F_LINK_TIMEOUT 128 /* has linked timeout */
-#define REQ_F_FAIL_LINK 256 /* fail rest of links */
-#define REQ_F_TIMEOUT 1024 /* timeout request */
-#define REQ_F_ISREG 2048 /* regular file */
-#define REQ_F_MUST_PUNT 4096 /* must be punted even for NONBLOCK */
-#define REQ_F_TIMEOUT_NOSEQ 8192 /* no timeout sequence */
-#define REQ_F_INFLIGHT 16384 /* on inflight list */
-#define REQ_F_COMP_LOCKED 32768 /* completion under lock */
-#define REQ_F_HARDLINK 65536 /* doesn't sever on completion < 0 */
-#define REQ_F_FORCE_ASYNC 131072 /* IOSQE_ASYNC */
-#define REQ_F_CUR_POS 262144 /* read/write uses file position */
u64 user_data;
u32 result;
u32 sequence;
@@ -4355,9 +4398,6 @@ static int io_req_set_file(struct io_submit_state *state, struct io_kiocb *req,
flags = READ_ONCE(sqe->flags);
fd = READ_ONCE(sqe->fd);
- if (flags & IOSQE_IO_DRAIN)
- req->flags |= REQ_F_IO_DRAIN;
-
if (!io_req_needs_file(req, fd))
return 0;
@@ -4593,8 +4633,9 @@ static bool io_submit_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe,
ret = -EINVAL;
goto err_req;
}
- if (sqe_flags & IOSQE_ASYNC)
- req->flags |= REQ_F_FORCE_ASYNC;
+ /* same numerical values with corresponding REQ_F_*, safe to copy */
+ req->flags |= sqe_flags & (IOSQE_IO_DRAIN|IOSQE_IO_HARDLINK|
+ IOSQE_ASYNC);
ret = io_req_set_file(state, req, sqe);
if (unlikely(ret)) {
@@ -4618,10 +4659,6 @@ static bool io_submit_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe,
head->flags |= REQ_F_IO_DRAIN;
ctx->drain_next = 1;
}
-
- if (sqe_flags & IOSQE_IO_HARDLINK)
- req->flags |= REQ_F_HARDLINK;
-
if (io_alloc_async_ctx(req)) {
ret = -EAGAIN;
goto err_req;
@@ -4648,9 +4685,6 @@ static bool io_submit_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe,
}
if (sqe_flags & (IOSQE_IO_LINK|IOSQE_IO_HARDLINK)) {
req->flags |= REQ_F_LINK;
- if (sqe_flags & IOSQE_IO_HARDLINK)
- req->flags |= REQ_F_HARDLINK;
-
INIT_LIST_HEAD(&req->link_list);
ret = io_req_defer_prep(req, sqe);
if (ret)
diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
index 955fd477e530..57d05cc5e271 100644
--- a/include/uapi/linux/io_uring.h
+++ b/include/uapi/linux/io_uring.h
@@ -45,14 +45,27 @@ struct io_uring_sqe {
};
};
+enum {
+ IOSQE_FIXED_FILE_BIT,
+ IOSQE_IO_DRAIN_BIT,
+ IOSQE_IO_LINK_BIT,
+ IOSQE_IO_HARDLINK_BIT,
+ IOSQE_ASYNC_BIT,
+};
+
/*
* sqe->flags
*/
-#define IOSQE_FIXED_FILE (1U << 0) /* use fixed fileset */
-#define IOSQE_IO_DRAIN (1U << 1) /* issue after inflight IO */
-#define IOSQE_IO_LINK (1U << 2) /* links next sqe */
-#define IOSQE_IO_HARDLINK (1U << 3) /* like LINK, but stronger */
-#define IOSQE_ASYNC (1U << 4) /* always go async */
+/* use fixed fileset */
+#define IOSQE_FIXED_FILE (1U << IOSQE_FIXED_FILE_BIT)
+/* issue after inflight IO */
+#define IOSQE_IO_DRAIN (1U << IOSQE_IO_DRAIN_BIT)
+/* links next sqe */
+#define IOSQE_IO_LINK (1U << IOSQE_IO_LINK_BIT)
+/* like LINK, but stronger */
+#define IOSQE_IO_HARDLINK (1U << IOSQE_IO_HARDLINK_BIT)
+/* always go async */
+#define IOSQE_ASYNC (1U << IOSQE_ASYNC_BIT)
/*
* io_uring_setup() flags
--
2.24.0