diff mbox series

[v8,7/7] io_uring: add api to set / get napi configuration.

Message ID 20230209230144.465620-8-shr@devkernel.io (mailing list archive)
State New
Headers show
Series io_uring: add napi busy polling support | expand

Commit Message

Stefan Roesch Feb. 9, 2023, 11:01 p.m. UTC 
This adds an api to register and unregister the napi prefer busy poll
setting from liburing. To be able to use this functionality, the
corresponding liburing patch is needed.

Signed-off-by: Stefan Roesch <shr@devkernel.io>
Acked-by: Jakub Kicinski <kuba@kernel.org>
---
 include/uapi/linux/io_uring.h | 3 ++-
 io_uring/napi.c               | 6 +++++-
 2 files changed, 7 insertions(+), 2 deletions(-)

Comments

Jens Axboe Feb. 10, 2023, 12:02 a.m. UTC | #1 
On 2/9/23 4:01 PM, Stefan Roesch wrote:
> This adds an api to register and unregister the napi prefer busy poll
> setting from liburing. To be able to use this functionality, the
> corresponding liburing patch is needed.

Same comment as for patch 6, and additionally the subject line here
is a dupe of the previous patch while this is not what this patch
does at all. It adds support for setting 'prefer_busy_poll', that
is what should be mentioned in the subject and explained in this
commit message.
diff mbox series

Patch

diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
index fe25ae92744d..e14f31a4b10c 100644
--- a/include/uapi/linux/io_uring.h
+++ b/include/uapi/linux/io_uring.h
@@ -647,7 +647,8 @@  struct io_uring_buf_reg {
 /* argument for IORING_(UN)REGISTER_NAPI */
 struct io_uring_napi {
 	__u32	busy_poll_to;
-	__u32	pad;
+	__u8	prefer_busy_poll;
+	__u8	pad[3];
 	__u64	resv;
 };
 
diff --git a/io_uring/napi.c b/io_uring/napi.c
index 34513b284234..a1605bef2bbc 100644
--- a/io_uring/napi.c
+++ b/io_uring/napi.c
@@ -203,15 +203,17 @@  int io_register_napi(struct io_ring_ctx *ctx, void __user *arg)
 {
 	const struct io_uring_napi curr = {
 		.busy_poll_to = ctx->napi_busy_poll_to,
+		.prefer_busy_poll = ctx->napi_prefer_busy_poll
 	};
 	struct io_uring_napi napi;
 
 	if (copy_from_user(&napi, arg, sizeof(napi)))
 		return -EFAULT;
-	if (napi.pad || napi.resv)
+	if (napi.pad[0] || napi.pad[1] || napi.pad[2] || napi.resv)
 		return -EINVAL;
 
 	WRITE_ONCE(ctx->napi_busy_poll_to, napi.busy_poll_to);
+	WRITE_ONCE(ctx->napi_prefer_busy_poll, !!napi.prefer_busy_poll);
 
 	if (copy_to_user(arg, &curr, sizeof(curr)))
 		return -EFAULT;
@@ -223,6 +225,7 @@  int io_unregister_napi(struct io_ring_ctx *ctx, void __user *arg)
 {
 	const struct io_uring_napi curr = {
 		.busy_poll_to = ctx->napi_busy_poll_to,
+		.prefer_busy_poll = ctx->napi_prefer_busy_poll
 	};
 
 	if (arg) {
@@ -231,6 +234,7 @@  int io_unregister_napi(struct io_ring_ctx *ctx, void __user *arg)
 	}
 
 	WRITE_ONCE(ctx->napi_busy_poll_to, 0);
+	WRITE_ONCE(ctx->napi_prefer_busy_poll, false);
 	return 0;
 }