From 2dbd9101b9910fe2c0fc2c23bc4d13a2604e9cca Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Wed, 7 May 2025 12:58:19 +0200 Subject: [PATCH] cyclic: make cyclic_unregister() idempotent Make cyclic_unregister() safe to call with an already unregistered, or possibly never registered, struct cyclic_info. This is similar to how the various timer APIs in the linux kernel work (they all allow calling delete/cancel/... on an inactive timer object). This means callers don't have to separately keep track of whether their cyclic callback is registered or not, and avoids them trying to peek into the struct cyclic_info for that information - which leads to somewhat ugly code as it would have to be guarded by ifdef CONFIG_CYCLIC. Signed-off-by: Rasmus Villemoes Reviewed-by: Stefan Roese --- common/cyclic.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/common/cyclic.c b/common/cyclic.c index b695f092f52..75662d9f613 100644 --- a/common/cyclic.c +++ b/common/cyclic.c @@ -28,6 +28,18 @@ struct hlist_head *cyclic_get_list(void) return (struct hlist_head *)&gd->cyclic_list; } +static bool cyclic_is_registered(const struct cyclic_info *cyclic) +{ + const struct cyclic_info *c; + + hlist_for_each_entry(c, cyclic_get_list(), list) { + if (c == cyclic) + return true; + } + + return false; +} + void cyclic_register(struct cyclic_info *cyclic, cyclic_func_t func, uint64_t delay_us, const char *name) { @@ -43,6 +55,9 @@ void cyclic_register(struct cyclic_info *cyclic, cyclic_func_t func, void cyclic_unregister(struct cyclic_info *cyclic) { + if (!cyclic_is_registered(cyclic)) + return; + hlist_del(&cyclic->list); } -- 2.39.5