[PATCH 03/20] riscv: cleanup send_ipi_mask

From: Christoph Hellwig
Date: Tue Sep 03 2019 - 05:32:52 EST


Use the special barriers for atomic bitops to make the intention
a little more clear, and use riscv_cpuid_to_hartid_mask instead of
open coding it.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Atish Patra <atish.patra@xxxxxxx>
---
arch/riscv/kernel/smp.c | 16 +++++++---------
1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
index 8cd730239613..2e21669aa068 100644
--- a/arch/riscv/kernel/smp.c
+++ b/arch/riscv/kernel/smp.c
@@ -80,17 +80,15 @@ static void ipi_stop(void)

static void send_ipi_mask(const struct cpumask *mask, enum ipi_message_type op)
{
- int cpuid, hartid;
struct cpumask hartid_mask;
+ int cpu;

- cpumask_clear(&hartid_mask);
- mb();
- for_each_cpu(cpuid, mask) {
- set_bit(op, &ipi_data[cpuid].bits);
- hartid = cpuid_to_hartid_map(cpuid);
- cpumask_set_cpu(hartid, &hartid_mask);
- }
- mb();
+ smp_mb__before_atomic();
+ for_each_cpu(cpu, mask)
+ set_bit(op, &ipi_data[cpu].bits);
+ smp_mb__after_atomic();
+
+ riscv_cpuid_to_hartid_mask(mask, &hartid_mask);
sbi_send_ipi(cpumask_bits(&hartid_mask));
}

--
2.20.1