liburing: add api for napi busy poll
v7 cover liburing: add api for napi busy poll
This adds two new api's to set/clear the napi busy poll settings. The two new functions are called:
- io_uring_register_napi
- io_uring_unregister_napi
The patch series also contains the documentation for the two new functions and two example programs. The client program is called napi-busy-poll-client and the server program napi-busy-poll-server. The client measures the roundtrip times of requests.
There is also a kernel patch "io-uring: support napi busy poll" to enable this feature on the kernel side.
Changes:
- V7:
- Add new functions to liburing-ffi.map file.
- Fix some whitespace issues.
- Address the compile errors from CI in the two files napi-busy-poll-client.c and napi-busy-poll-server.c
- V6:
- Check return value of unregister napi call and verify that busy poll timeout and prefer busy poll return the expected values.
- V5:
- Fixes to documentation.
- Correct opcode for unregister call
- Initialize napi structure in example programs
- Address tab issues in recordRTT()
- V4:
- Modify functions to use a structure to pass the napi busy poll settings to the kernel.
- Return previous values when returning from the above functions.
- Rename the functions and remove one function (no longer needed as the data is passed as a structure)
- V3:
- Updated liburing.map file
- Moved example programs from the test directory to the example directory. The two example programs don't fit well in the test category and need to be run from separate hosts.
- Added the io_uring_register_napi_prefer_busy_poll API.
- Added the call to io_uring_register_napi_prefer_busy_poll to the example programs
- Updated the documentation
- V2:
- Updated the liburing.map file for the two new functions. (added a 2.4 section)
- Added a description of the new feature to the changelog file
- Fixed the indentation of the longopts structure
- Used defined exit constants
- Fixed encodeUserData to support 32 bit builds
Stefan Roesch (4):
liburing: add api to set napi busy poll settings
liburing: add documentation for new napi busy polling
liburing: add example programs for napi busy poll
liburing: update changelog with new feature
.gitignore | 2 + CHANGELOG | 1 + examples/Makefile | 2 + examples/napi-busy-poll-client.c | 451 +++++++++++++++++++++++++++++++ examples/napi-busy-poll-server.c | 386 ++++++++++++++++++++++++++ man/io_uring_register_napi.3 | 40 +++ man/io_uring_unregister_napi.3 | 27 ++ src/include/liburing.h | 3 + src/include/liburing/io_uring.h | 12 + src/liburing-ffi.map | 2 + src/liburing.map | 3 + src/register.c | 12 + 12 files changed, 941 insertions(+) create mode 100644 examples/napi-busy-poll-client.c create mode 100644 examples/napi-busy-poll-server.c create mode 100644 man/io_uring_register_napi.3 create mode 100644 man/io_uring_unregister_napi.3
base-commit: d32d53b65377d846635387ce6c1cd2ed0d700f92
Signature · 1 line
2.30.2
PATCH v7 1/4 liburing: add api to set napi busy poll settings
This adds two functions to manage the napi busy poll settings:
- io_uring_register_napi
- io_uring_unregister_napi
--- src/include/liburing.h | 3 +++ src/include/liburing/io_uring.h | 12 ++++++++++++ src/liburing-ffi.map | 2 ++ src/liburing.map | 3 +++ src/register.c | 12 ++++++++++++ 5 files changed, 32 insertions(+)
src/include/liburing.h +3 -0
@@ -240,6 +240,9 @@ int io_uring_register_sync_cancel(struct io_uring *ring,int io_uring_register_file_alloc_range (struct io_uring *ring,unsigned off,unsigned len); +int io_uring_register_napi (struct io_uring *ring,struct io_uring_napi *napi); +int io_uring_unregister_napi (struct io_uring *ring,struct io_uring_napi *napi); +int io_uring_get_events (struct io_uring *ring);int io_uring_submit_and_get_events (struct io_uring *ring);
src/include/liburing/io_uring.h +12 -0
@@ -518,6 +518,10 @@ enum {/* register a range of fixed file slots for automatic slot allocation */ IORING_REGISTER_FILE_ALLOC_RANGE =25 , +/* set/clear busy poll settings */ +IORING_REGISTER_NAPI =26 , +IORING_UNREGISTER_NAPI =27 , +/* this goes last */ IORING_REGISTER_LAST };
@@ -640,6 +644,14 @@ struct io_uring_buf_reg {__u64 resv[3 ]; }; +/* argument for IORING_(UN)REGISTER_NAPI */ +struct io_uring_napi { +__u32 busy_poll_to; +__u8 prefer_busy_poll; +__u8 pad[3 ]; +__u64 resv; +}; +/* * io_uring_restriction->opcode values */
src/liburing-ffi.map +2 -0
@@ -166,6 +166,8 @@ LIBURING_2.4 { io_uring_prep_recv; io_uring_prep_msg_ring_cqe_flags; io_uring_prep_msg_ring_fd; + io_uring_register_napi; + io_uring_unregister_napi; local: *; };
src/liburing.map +3 -0
@@ -76,4 +76,7 @@ LIBURING_2.4 { io_uring_enable_rings; io_uring_register_restrictions; + + io_uring_register_napi; + io_uring_unregister_napi; } LIBURING_2.3;
src/register.c +12 -0
@@ -342,3 +342,15 @@ int io_uring_register_file_alloc_range(struct io_uring *ring,IORING_REGISTER_FILE_ALLOC_RANGE , &range, 0); } + +int io_uring_register_napi (struct io_uring *ring,struct io_uring_napi *napi) +{ +return __sys_io_uring_register (ring->ring_fd, +IORING_REGISTER_NAPI , napi,0 ); +} + +int io_uring_unregister_napi (struct io_uring *ring,struct io_uring_napi *napi) +{ +return __sys_io_uring_register (ring->ring_fd, +IORING_UNREGISTER_NAPI , napi,0 ); +}
Signature · 1 line
2.30.2
PATCH v7 2/4 liburing: add documentation for new napi busy polling
In reply to Stefan RoeschThis adds two man pages for the two new functions:
- io_uring_register_nap
- io_uring_unregister_napi
--- man/io_uring_register_napi.3 | 40 ++++++++++++++++++++++++++++++++++ man/io_uring_unregister_napi.3 | 27 +++++++++++++++++++++++ 2 files changed, 67 insertions(+) create mode 100644 man/io_uring_register_napi.3 create mode 100644 man/io_uring_unregister_napi.3
man/io_uring_register_napi.3 new file +40 -0
@@ -0,0 +1,40 @@ +.\" Copyright (C) 2022 Stefan Roesch <[email protected]> +.\" +.\" SPDX-License-Identifier: LGPL-2.0-or-later +.\" +.TH io_uring_register_napi 3 "November 16, 2022" "liburing-2.4" "liburing Manual" +.SH NAME +io_uring_register_napi \- register NAPI busy poll settings +.SH SYNOPSIS +.nf +.B #include <liburing.h> +.PP +.BI "int io_uring_register_napi(struct io_uring *" ring "," +.BI " struct io_uring_napi *" napi) +.PP +.fi +.SH DESCRIPTION +.PP +The +.BR io_uring_register_napi (3) +function registers the NAPI settings for subsequent operations. The NAPI +settings are specified in the structure that is passed in the +.I napi +parameter. The structure consists of the napi timeout +.I busy_poll_to +(napi busy poll timeout in us) and +.I prefer_busy_poll. + +Registering a NAPI settings sets the mode when calling the function +napi_busy_loop and corresponds to the SO_PREFER_BUSY_POLL socket +option. + +NAPI busy poll can reduce the network roundtrip time. + + +.SH RETURN VALUE +On success +.BR io_uring_register_napi (3) +return 0. On failure they return +.BR -errno . +It also updates the napi structure with the current values.
man/io_uring_unregister_napi.3 new file +27 -0
@@ -0,0 +1,27 @@ +.\" Copyright (C) 2022 Stefan Roesch <[email protected]> +.\" +.\" SPDX-License-Identifier: LGPL-2.0-or-later +.\" +.TH io_uring_unregister_napi 3 "November 16, 2022" "liburing-2.4" "liburing Manual" +.SH NAME +io_uring_unregister_napi \- unregister NAPI busy poll settings +.SH SYNOPSIS +.nf +.B #include <liburing.h> +.PP +.BI "int io_uring_unregister_napi(struct io_uring *" ring "," +.BI " struct io_uring_napi *" napi) +.PP +.fi +.SH DESCRIPTION +.PP +The +.BR io_uring_unregister_napi (3) +function unregisters the NAPI busy poll settings for subsequent operations. + +.SH RETURN VALUE +On success +.BR io_uring_unregister_napi (3) +return 0. On failure they return +.BR -errno . +It also updates the napi structure with the current values.
Signature · 1 line
2.30.2
PATCH v7 3/4 liburing: add example programs for napi busy poll
In reply to Stefan RoeschThis adds two example programs to test the napi busy poll functionality. It consists of a client program and a server program. To get a napi id, the client and the server program need to be run on different hosts.
To test the napi busy poll timeout, the -t needs to be specified. A reasonable value for the busy poll timeout is 100. By specifying the busy poll timeout on the server and the client the best results are accomplished.
--- .gitignore | 2 + examples/Makefile | 2 + examples/napi-busy-poll-client.c | 451 +++++++++++++++++++++++++++++++ examples/napi-busy-poll-server.c | 386 ++++++++++++++++++++++++++ 4 files changed, 841 insertions(+) create mode 100644 examples/napi-busy-poll-client.c create mode 100644 examples/napi-busy-poll-server.c
.gitignore +2 -0
@@ -18,6 +18,8 @@ /examples/io_uring-test /examples/io_uring-udp /examples/link-cp +/examples/napi-busy-poll-client +/examples/napi-busy-poll-server /examples/ucontext-cp /examples/poll-bench /examples/send-zerocopy
examples/Makefile +2 -0
@@ -15,6 +15,8 @@ example_srcs := \ io_uring-test.c \ io_uring-udp.c \ link-cp.c \ + napi-busy-poll-client.c \ + napi-busy-poll-server.c \ poll-bench.c \ send-zerocopy.c
examples/napi-busy-poll-client.c new file +451 -0
451 lines not on this page · raw message
examples/napi-busy-poll-server.c new file +386 -0
386 lines not on this page · raw message
Signature · 1 line
2.30.2
PATCH v7 4/4 liburing: update changelog with new feature
In reply to Stefan RoeschAdd a new entry to the changelog file for the napi busy poll feature.
--- CHANGELOG | 1 + 1 file changed, 1 insertion(+)
CHANGELOG +1 -0
@@ -6,6 +6,7 @@ liburing-2.4 release - Add io_uring_prep_msg_ring_cqe_flags() function. - Deprecate --nolibc configure option. - CONFIG_NOLIBC is always enabled on x86-64, x86, and aarch64. +- Support for napi busy polling liburing-2.3 release
Signature · 1 line
2.30.2
Re: [PATCH v7 1/4] liburing: add api to set napi busy poll settings
In reply to Stefan Roeschsrc/liburing-ffi.map LIBURING_2.4 { · line 173
Quoted 13 lines · Stefan Roesch
src/liburing-ffi.map +2
-0@@ -166,6 +166,8 @@ LIBURING_2.4 { io_uring_prep_recv; io_uring_prep_msg_ring_cqe_flags; io_uring_prep_msg_ring_fd; + io_uring_register_napi; + io_uring_unregister_napi; local: *; };
Use tab for indentation. Not spaces. With that fixed:
Signature · 1 line
Ammar Faizi
Re: [PATCH v7 2/4] liburing: add documentation for new napi busy polling
In reply to Stefan Roeschman/io_uring_register_napi.3 line 26
Quoted 9 lines · Stefan Roesch
man/io_uring_register_napi.3 new file +9
-0+The +.BR io_uring_register_napi (3) +function registers the NAPI settings for subsequent operations. The NAPI +settings are specified in the structure that is passed in the +.I napi +parameter. The structure consists of the napi timeout +.I busy_poll_to +(napi busy poll timeout in us) and +.I prefer_busy_poll.
nit: That "period" after "prefer_busy_poll" will be underlined if you write it that way. It would be better if you write:
.IR prefer_busy_poll .
so that the dot is not underlined when you open that manpage from a terminal. But not a big deal..
Signature · 1 line
Ammar Faizi
Re: [PATCH v7 3/4] liburing: add example programs for napi busy poll
In reply to Stefan RoeschQuoted 10 lines · Stefan Roesch
This adds two example programs to test the napi busy poll functionality. It consists of a client program and a server program. To get a napi id, the client and the server program need to be run on different hosts.
To test the napi busy poll timeout, the -t needs to be specified. A reasonable value for the busy poll timeout is 100. By specifying the busy poll timeout on the server and the client the best results are accomplished.
Signed-off-by Stefan Roesch <[email protected]>
This version is much better. No more whitespace issues and the CI is all green.
Signature · 1 line
Ammar Faizi
Re: [PATCH v7 4/4] liburing: update changelog with new feature
In reply to Stefan RoeschQuoted 3 lines · Stefan Roesch
Add a new entry to the changelog file for the napi busy poll feature.
Signed-off-by Stefan Roesch <[email protected]>
Signature · 1 line
Ammar Faizi