diff mbox series

[net-next,v4,4/7] eventpoll: Trigger napi_busy_loop, if prefer_busy_poll is set

Message ID 20241102005214.32443-5-jdamato@fastly.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series Suspend IRQs during application busy periods | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next, async
netdev/ynl success Generated files up to date; no warnings/errors; GEN HAS DIFF 2 files changed, 19 insertions(+);
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 3 this patch: 3
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 4 of 4 maintainers
netdev/build_clang success Errors and warnings before: 3 this patch: 3
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 7 this patch: 7
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 10 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-11-02--06-00 (tests: 779)

Commit Message

Joe Damato Nov. 2, 2024, 12:52 a.m. UTC 
From: Martin Karsten <mkarsten@uwaterloo.ca>

Setting prefer_busy_poll now leads to an effectively nonblocking
iteration though napi_busy_loop, even when busy_poll_usecs is 0.

Signed-off-by: Martin Karsten <mkarsten@uwaterloo.ca>
Co-developed-by: Joe Damato <jdamato@fastly.com>
Signed-off-by: Joe Damato <jdamato@fastly.com>
Tested-by: Joe Damato <jdamato@fastly.com>
Tested-by: Martin Karsten <mkarsten@uwaterloo.ca>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
---
 v1 -> v2:
   - Rebased to apply now that commit b9ca079dd6b0 ("eventpoll: Annotate
     data-race of busy_poll_usecs") has been picked up from VFS.

 fs/eventpoll.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

Comments

Samudrala, Sridhar Nov. 2, 2024, 11:33 p.m. UTC | #1 
On 11/1/2024 7:52 PM, Joe Damato wrote:
> From: Martin Karsten <mkarsten@uwaterloo.ca>
> 
> Setting prefer_busy_poll now leads to an effectively nonblocking
> iteration though napi_busy_loop, even when busy_poll_usecs is 0.
> 
> Signed-off-by: Martin Karsten <mkarsten@uwaterloo.ca>
> Co-developed-by: Joe Damato <jdamato@fastly.com>
> Signed-off-by: Joe Damato <jdamato@fastly.com>
> Tested-by: Joe Damato <jdamato@fastly.com>
> Tested-by: Martin Karsten <mkarsten@uwaterloo.ca>
> Acked-by: Stanislav Fomichev <sdf@fomichev.me>
> ---
Reviewed-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
diff mbox series

Patch

diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 1ae4542f0bd8..f9e0d9307dad 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -420,7 +420,9 @@  static bool busy_loop_ep_timeout(unsigned long start_time,
 
 static bool ep_busy_loop_on(struct eventpoll *ep)
 {
-	return !!READ_ONCE(ep->busy_poll_usecs) || net_busy_loop_on();
+	return !!READ_ONCE(ep->busy_poll_usecs) ||
+	       READ_ONCE(ep->prefer_busy_poll) ||
+	       net_busy_loop_on();
 }
 
 static bool ep_busy_loop_end(void *p, unsigned long start_time)