summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorSascha Hauer <s.hauer@pengutronix.de>2016-01-12 13:50:21 +0100
committerSascha Hauer <s.hauer@pengutronix.de>2016-01-13 15:55:23 +0100
commitefd9601e15b030317eeda1618985bac34ebfcb9a (patch)
tree68e3385e007711a0ef084079fd17a5482f8f916d
parent96b115be942ed8dcc94a5230fce0eafb4ac93f2d (diff)
downloadbarebox-efd9601e15b030317eeda1618985bac34ebfcb9a.tar.gz
poller: Fix async poller
The async poller does not work as expected since it can happen that the async poller is removed from the list of pollers while we are iterating over the list. Even list_for_each_entry_safe does not help here since we may remove the next list element, but list_for_each_entry_safe only allows to remove the current list element. Rework the async poller so that it is registered with the poller framework on registration and then is only marked as active with poller_call_async(). This way we do not have to do list manipulations while running the pollers. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
-rw-r--r--common/poller.c26
-rw-r--r--include/poller.h4
2 files changed, 26 insertions, 4 deletions
diff --git a/common/poller.c b/common/poller.c
index 496636d..32795b6 100644
--- a/common/poller.c
+++ b/common/poller.c
@@ -32,6 +32,7 @@ int poller_unregister(struct poller_struct *poller)
if (!poller->registered)
return -ENODEV;
+
list_del(&poller->list);
poller->registered = 0;
@@ -42,12 +43,14 @@ static void poller_async_callback(struct poller_struct *poller)
{
struct poller_async *pa = container_of(poller, struct poller_async, poller);
+ if (!pa->active)
+ return;
+
if (get_time_ns() < pa->end)
return;
+ pa->active = 0;
pa->fn(pa->ctx);
- pa->fn = NULL;
- poller_unregister(&pa->poller);
}
/*
@@ -62,7 +65,9 @@ static void poller_async_callback(struct poller_struct *poller)
*/
int poller_async_cancel(struct poller_async *pa)
{
- return poller_unregister(&pa->poller);
+ pa->active = 0;
+
+ return 0;
}
/*
@@ -80,13 +85,26 @@ int poller_call_async(struct poller_async *pa, uint64_t delay_ns,
void (*fn)(void *), void *ctx)
{
pa->ctx = ctx;
- pa->poller.func = poller_async_callback;
pa->end = get_time_ns() + delay_ns;
pa->fn = fn;
+ pa->active = 1;
+
+ return 0;
+}
+
+int poller_async_register(struct poller_async *pa)
+{
+ pa->poller.func = poller_async_callback;
+ pa->active = 0;
return poller_register(&pa->poller);
}
+int poller_async_unregister(struct poller_async *pa)
+{
+ return poller_unregister(&pa->poller);
+}
+
void poller_call(void)
{
struct poller_struct *poller, *tmp;
diff --git a/include/poller.h b/include/poller.h
index cda5b57..35a2271 100644
--- a/include/poller.h
+++ b/include/poller.h
@@ -26,8 +26,12 @@ struct poller_async {
void (*fn)(void *);
void *ctx;
uint64_t end;
+ int active;
};
+int poller_async_register(struct poller_async *pa);
+int poller_async_unregister(struct poller_async *pa);
+
int poller_call_async(struct poller_async *pa, uint64_t delay_ns,
void (*fn)(void *), void *ctx);
int poller_async_cancel(struct poller_async *pa);