riscv: cleanup send_ipi_mask

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@lst.de>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>

diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
index 8cd7302..2e21669 100644 (file)
--- 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));
 }