[PATCH v8 4/4] arm64: switch to irq_stack during softirq
james.morse at arm.com
Tue Dec 8 02:29:58 PST 2015
On 04/12/15 18:40, Catalin Marinas wrote:
> BTW, at which point does in_irq() return true for an interrupt (and when
> it ceases to do so)?
It uses hardirq_count(), so its true between irq_enter() and irq_exit().
The calls out from handle_IPI() are wrapped by these (except
scheduler_ipi(), which calls them itself).
The other route looks like:
gic_handle_irq() -> __handle_domain_irq()
which wraps generic_handle_irq() in irq_enter()/irq_exit().
I don't know how chained_irq_enter() changes/affects this.
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