diff mbox series

[1/9] softirq: Rewrite softirq processing loop

Message ID 20230505113315.3307723-2-liujian56@huawei.com (mailing list archive)
State Not Applicable
Headers show
Series fix softlockup in run_timer_softirq | expand

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Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Guessed tree name to be net-next
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: 10 this patch: 10
netdev/cc_maintainers warning 1 maintainers not CCed: clingutla@codeaurora.org
netdev/build_clang success Errors and warnings before: 8 this patch: 8
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: 10 this patch: 10
netdev/checkpatch warning CHECK: From:/Signed-off-by: email comments mismatch: 'From: Peter Zijlstra <peterz@infradead.org>' != 'Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>'
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Liu Jian May 5, 2023, 11:33 a.m. UTC 
From: Peter Zijlstra <peterz@infradead.org>

Simplify the softirq processing loop by using the bitmap APIs

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Liu Jian <liujian56@huawei.com>
---
 kernel/softirq.c | 16 ++++++----------
 1 file changed, 6 insertions(+), 10 deletions(-)
diff mbox series

Patch

diff --git a/kernel/softirq.c b/kernel/softirq.c
index 1b725510dd0f..bff5debf6ce6 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -531,9 +531,9 @@  asmlinkage __visible void __softirq_entry __do_softirq(void)
 	unsigned long old_flags = current->flags;
 	int max_restart = MAX_SOFTIRQ_RESTART;
 	struct softirq_action *h;
+	unsigned long pending;
+	unsigned int vec_nr;
 	bool in_hardirq;
-	__u32 pending;
-	int softirq_bit;
 
 	/*
 	 * Mask out PF_MEMALLOC as the current task context is borrowed for the
@@ -554,15 +554,13 @@  asmlinkage __visible void __softirq_entry __do_softirq(void)
 
 	local_irq_enable();
 
-	h = softirq_vec;
+	for_each_set_bit(vec_nr, &pending, NR_SOFTIRQS) {
+		unsigned int prev_count;
 
-	while ((softirq_bit = ffs(pending))) {
-		unsigned int vec_nr;
-		int prev_count;
+		__clear_bit(vec_nr, &pending);
 
-		h += softirq_bit - 1;
+		h = softirq_vec + vec_nr;
 
-		vec_nr = h - softirq_vec;
 		prev_count = preempt_count();
 
 		kstat_incr_softirqs_this_cpu(vec_nr);
@@ -576,8 +574,6 @@  asmlinkage __visible void __softirq_entry __do_softirq(void)
 			       prev_count, preempt_count());
 			preempt_count_set(prev_count);
 		}
-		h++;
-		pending >>= softirq_bit;
 	}
 
 	if (!IS_ENABLED(CONFIG_PREEMPT_RT) &&