On 26. 12. 22, 7:21, Deepak R Varma wrote:
The refcount_* APIs are designed to address known issues with the
atomic_t APIs for reference counting. They provide following distinct
advantages:
- protect the reference counters from overflow/underflow
- avoid use-after-free errors
- provide improved memory ordering guarantee schemes
- neater and safer.
Hence, replace the atomic_* APIs by their equivalent refcount_t
API functions.
This patch proposal address the following warnings generated by
the atomic_as_refcounter.cocci coccinelle script
atomic_add_return(-1, ...)
...
--- a/drivers/tty/serial/dz.c
+++ b/drivers/tty/serial/dz.c
...
@@ -400,18 +399,16 @@ static int dz_startup(struct uart_port *uport)
struct dz_port *dport = to_dport(uport);
struct dz_mux *mux = dport->mux;
unsigned long flags;
- int irq_guard;
int ret;
u16 tmp;
- irq_guard = atomic_add_return(1, &mux->irq_guard);
- if (irq_guard != 1)
+ refcount_inc(&mux->irq_guard);
+ if (refcount_read(&mux->irq_guard) != 1)
return 0;
- ret = request_irq(dport->port.irq, dz_interrupt,
- IRQF_SHARED, "dz", mux);
+ ret = request_irq(dport->port.irq, dz_interrupt, IRQF_SHARED, "dz", mux);
How is this related to the above described change?
--
js
suse labs
