[PATCH 13/15] irq: riscv: perform irqentry in entry code

Mark Rutland
2021-10-21T18:03:56Z

In preparation for removing HANDLE_DOMAIN_IRQ_IRQENTRY, have arch/riscv
perform all the irqentry accounting in its entry code. As arch/riscv
uses GENERIC_IRQ_MULTI_HANDLER, we can use generic_handle_arch_irq() to
do so.

Since generic_handle_arch_irq() handles the irq entry and setting the
irq regs, and happens before the irqchip code calls handle_IPI(), we can
remove the redundant irq entry and irq regs manipulation from
handle_IPI().

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
---
arch/riscv/Kconfig | 1 -
arch/riscv/kernel/entry.S | 3 +--
arch/riscv/kernel/smp.c | 9 +--------
3 files changed, 2 insertions(+), 11 deletions(-)

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 740653063a56..301a54233c7e 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -63,7 +63,6 @@ config RISCV
select GENERIC_SMP_IDLE_THREAD
select GENERIC_TIME_VSYSCALL if MMU && 64BIT
select HANDLE_DOMAIN_IRQ
- select HANDLE_DOMAIN_IRQ_IRQENTRY
select HAVE_ARCH_AUDITSYSCALL
select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL
diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S
index 98f502654edd..64236f7efde5 100644
--- a/arch/riscv/kernel/entry.S
+++ b/arch/riscv/kernel/entry.S
@@ -130,8 +130,7 @@ skip_context_tracking:

/* Handle interrupts */
move a0, sp /* pt_regs */
- la a1, handle_arch_irq
- REG_L a1, (a1)
+ la a1, generic_handle_arch_irq
jr a1
1:
/*
diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
index 921d9d7df400..2f6da845c9ae 100644
--- a/arch/riscv/kernel/smp.c
+++ b/arch/riscv/kernel/smp.c
@@ -140,12 +140,9 @@ void arch_irq_work_raise(void)

void handle_IPI(struct pt_regs *regs)
{
- struct pt_regs *old_regs = set_irq_regs(regs);
unsigned long *pending_ipis = &ipi_data[smp_processor_id()].bits;
unsigned long *stats = ipi_data[smp_processor_id()].stats;

- irq_enter();
-
riscv_clear_ipi();

while (true) {
@@ -156,7 +153,7 @@ void handle_IPI(struct pt_regs *regs)

ops = xchg(pending_ipis, 0);
if (ops == 0)
- goto done;
+ return;

if (ops & (1 << IPI_RESCHEDULE)) {
stats[IPI_RESCHEDULE]++;
@@ -189,10 +186,6 @@ void handle_IPI(struct pt_regs *regs)
/* Order data access and bit testing. */
mb();
}
-
-done:
- irq_exit();
- set_irq_regs(old_regs);
}

static const char * const ipi_names[] = {
--
2.11.0