riscv: refactor the IPI code

This prepares for adding native non-SBI IPI code.
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>

arch/riscv/kernel/smp.c

@@ -78,13 +78,38 @@ static void ipi_stop(void)
 		wait_for_interrupt();
 }
 
+static void send_ipi_mask(const struct cpumask *mask, enum ipi_message_type op)
+{
+	int cpuid, hartid;
+	struct cpumask hartid_mask;
+
+	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();
+	sbi_send_ipi(cpumask_bits(&hartid_mask));
+}
+
+static void send_ipi_single(int cpu, enum ipi_message_type op)
+{
+	send_ipi_mask(cpumask_of(cpu), op);
+}
+
+static inline void clear_ipi(void)
+{
+	csr_clear(CSR_SIP, SIE_SSIE);
+}
+
 void riscv_software_interrupt(void)
 {
 	unsigned long *pending_ipis = &ipi_data[smp_processor_id()].bits;
 	unsigned long *stats = ipi_data[smp_processor_id()].stats;
 
-	/* Clear pending IPI */
-	csr_clear(CSR_SIP, SIE_SSIE);
+	clear_ipi();
 
 	while (true) {
 		unsigned long ops;
@@ -118,23 +143,6 @@ void riscv_software_interrupt(void)
 	}
 }
 
-static void
-send_ipi_message(const struct cpumask *to_whom, enum ipi_message_type operation)
-{
-	int cpuid, hartid;
-	struct cpumask hartid_mask;
-
-	cpumask_clear(&hartid_mask);
-	mb();
-	for_each_cpu(cpuid, to_whom) {
-		set_bit(operation, &ipi_data[cpuid].bits);
-		hartid = cpuid_to_hartid_map(cpuid);
-		cpumask_set_cpu(hartid, &hartid_mask);
-	}
-	mb();
-	sbi_send_ipi(cpumask_bits(&hartid_mask));
-}
-
 static const char * const ipi_names[] = {
 	[IPI_RESCHEDULE]	= "Rescheduling interrupts",
 	[IPI_CALL_FUNC]		= "Function call interrupts",
@@ -156,12 +164,12 @@ void show_ipi_stats(struct seq_file *p, int prec)
 
 void arch_send_call_function_ipi_mask(struct cpumask *mask)
 {
-	send_ipi_message(mask, IPI_CALL_FUNC);
+	send_ipi_mask(mask, IPI_CALL_FUNC);
 }
 
 void arch_send_call_function_single_ipi(int cpu)
 {
-	send_ipi_message(cpumask_of(cpu), IPI_CALL_FUNC);
+	send_ipi_single(cpu, IPI_CALL_FUNC);
 }
 
 void smp_send_stop(void)
@@ -176,7 +184,7 @@ void smp_send_stop(void)
 
 		if (system_state <= SYSTEM_RUNNING)
 			pr_crit("SMP: stopping secondary CPUs\n");
-		send_ipi_message(&mask, IPI_CPU_STOP);
+		send_ipi_mask(&mask, IPI_CPU_STOP);
 	}
 
 	/* Wait up to one second for other CPUs to stop */
@@ -191,6 +199,5 @@ void smp_send_stop(void)
 
 void smp_send_reschedule(int cpu)
 {
-	send_ipi_message(cpumask_of(cpu), IPI_RESCHEDULE);
+	send_ipi_single(cpu, IPI_RESCHEDULE);
 }
-