ARC: opencode arc_request_percpu_irq
- The idea is to remove the API usage since it has a subltle
design flaw - relies on being called on cpu0 first. This is true for
some early per cpu irqs such as TIMER/IPI, but not for late probed
per cpu peripherals such a perf. And it's usage in perf has already
bitten us once: see c6317bc7c5ab
("ARCv2: perf: Ensure perf intr gets enabled on all cores") where we
ended up open coding it anyways
- The seeming duplication will go away once we start using cpu notifier
for timer setup
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
diff --git a/arch/arc/kernel/smp.c b/arch/arc/kernel/smp.c
index 4cb3add..ca83ebe 100644
--- a/arch/arc/kernel/smp.c
+++ b/arch/arc/kernel/smp.c
@@ -346,6 +346,10 @@
/*
* API called by platform code to hookup arch-common ISR to their IPI IRQ
+ *
+ * Note: If IPI is provided by platform (vs. say ARC MCIP), their intc setup/map
+ * function needs to call call irq_set_percpu_devid() for IPI IRQ, otherwise
+ * request_percpu_irq() below will fail
*/
static DEFINE_PER_CPU(int, ipi_dev);
@@ -353,7 +357,16 @@
{
int *dev = per_cpu_ptr(&ipi_dev, cpu);
- arc_request_percpu_irq(irq, cpu, do_IPI, "IPI Interrupt", dev);
+ /* Boot cpu calls request, all call enable */
+ if (!cpu) {
+ int rc;
+
+ rc = request_percpu_irq(irq, do_IPI, "IPI Interrupt", dev);
+ if (rc)
+ panic("Percpu IRQ request failed for %d\n", irq);
+ }
+
+ enable_percpu_irq(irq, 0);
return 0;
}