Unverified Commit d3a194d9 authored by Lin Feng's avatar Lin Feng Committed by Christian Brauner
Browse files

epoll: simplify ep_busy_loop by removing always 0 argument 



Commit 00b27634("epoll: replace gotos with a proper loop") refactored
ep_poll and always feeds ep_busy_loop with a time_out value of 0, nonblock
mode for ep_busy_loop has sunk since, IOW nonblock mode checking has been
taken over by ep_poll itself, codes snipped:

static int ep_poll(struct eventpoll *ep...
{
...
    if (timed_out)
        return 0;

    eavail = ep_busy_loop(ep, timed_out);
...
}

Given this fact codes can be simplified a bit for ep_busy_loop.

Signed-off-by: default avatarLin Feng <linf@wangsu.com>
Link: https://lore.kernel.org/r/20250227033412.5873-1-linf@wangsu.com


Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 12851bd9

fs/eventpoll.c

+4 −4
Original line number Diff line number Diff line
@@ -438,7 +438,7 @@ static bool ep_busy_loop_end(void *p, unsigned long start_time) 
 *

 * we must do our busy polling with irqs enabled

 */

static bool ep_busy_loop(struct eventpoll *ep, int nonblock)

static bool ep_busy_loop(struct eventpoll *ep)

{

	unsigned int napi_id = READ_ONCE(ep->napi_id);

	u16 budget = READ_ONCE(ep->busy_poll_budget);
@@ -448,7 +448,7 @@ static bool ep_busy_loop(struct eventpoll *ep, int nonblock) 
		budget = BUSY_POLL_BUDGET;



	if (napi_id >= MIN_NAPI_ID && ep_busy_loop_on(ep)) {

		napi_busy_loop(napi_id, nonblock ? NULL : ep_busy_loop_end,

		napi_busy_loop(napi_id, ep_busy_loop_end,

			       ep, prefer_busy_poll, budget);

		if (ep_events_available(ep))

			return true;
@@ -560,7 +560,7 @@ static void ep_resume_napi_irqs(struct eventpoll *ep) 


#else



static inline bool ep_busy_loop(struct eventpoll *ep, int nonblock)

static inline bool ep_busy_loop(struct eventpoll *ep)

{

	return false;

}
@@ -2047,7 +2047,7 @@ static int ep_poll(struct eventpoll *ep, struct epoll_event __user *events, 
		if (timed_out)

			return 0;



		eavail = ep_busy_loop(ep, timed_out);

		eavail = ep_busy_loop(ep);

		if (eavail)

			continue;