poll_wait: kill the obsolete wait_address check

oleg-nesterov · brauner · commit 10b02a2cfec2 · 2025-01-10T11:58:59.000+01:00
This check is historical and no longer needed, wait_address is never NULL. These days we rely on the poll_table->_qproc check. NULL if select/poll is not going to sleep, or it already has a data to report, or all waiters have already been registered after the 1st iteration. However, poll_table *p can be NULL, see p9_fd_poll() for example, so we can't remove the "p != NULL" check. Link: https://lore.kernel.org/all/20250106180325.GF7233@redhat.com/ Signed-off-by: Oleg Nesterov <oleg@redhat.com> Link: https://lore.kernel.org/r/20250107162724.GA18926@redhat.com Signed-off-by: Christian Brauner <brauner@kernel.org>
diff --git a/include/linux/poll.h b/include/linux/poll.h
@@ -41,7 +41,7 @@ typedef struct poll_table_struct {
 
 static inline void poll_wait(struct file * filp, wait_queue_head_t * wait_address, poll_table *p)
 {
-	if (p && p->_qproc && wait_address) {
+	if (p && p->_qproc) {
 		p->_qproc(filp, wait_address, p);
 		/*
 		 * This memory barrier is paired in the wq_has_sleeper().

Original file line number	Diff line number	Diff line change
`@@ -41,7 +41,7 @@ typedef struct poll_table_struct {`
`41`	`41`
`42`	`42`	`static inline void poll_wait(struct file * filp, wait_queue_head_t * wait_address, poll_table *p)`
`43`	`43`	`{`
`44`		`- if (p && p->_qproc && wait_address) {`
	`44`	`+ if (p && p->_qproc) {`
`45`	`45`	`p->_qproc(filp, wait_address, p);`
`46`	`46`	`/*`
`47`	`47`	`* This memory barrier is paired in the wq_has_sleeper().`