powerpc: Provide a separate handler for each IPI action
With the new generic smp call function helpers, I noticed the code in
smp_message_recv was a single function call in many cases. While
getting the message number from the ipi data is easy, we can reduce
the path length by a function and data-dependent switch by registering
seperate IPI actions for these simple calls.
Originally I left the ipi action array exposed, but then I realized the
registration code should be common too.
The three users each had their own name array, so I made a fourth
to convert all users to use a common one.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/include/asm/smp.h b/arch/powerpc/include/asm/smp.h
index 1866cec..c25f73d 100644
--- a/arch/powerpc/include/asm/smp.h
+++ b/arch/powerpc/include/asm/smp.h
@@ -81,6 +81,13 @@
#define PPC_MSG_CALL_FUNC_SINGLE 2
#define PPC_MSG_DEBUGGER_BREAK 3
+/*
+ * irq controllers that have dedicated ipis per message and don't
+ * need additional code in the action handler may use this
+ */
+extern int smp_request_message_ipi(int virq, int message);
+extern const char *smp_ipi_name[];
+
void smp_init_iSeries(void);
void smp_init_pSeries(void);
void smp_init_cell(void);
diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index ff9f701..a59d8d7 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -123,6 +123,65 @@
}
}
+static irqreturn_t call_function_action(int irq, void *data)
+{
+ generic_smp_call_function_interrupt();
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t reschedule_action(int irq, void *data)
+{
+ /* we just need the return path side effect of checking need_resched */
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t call_function_single_action(int irq, void *data)
+{
+ generic_smp_call_function_single_interrupt();
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t debug_ipi_action(int irq, void *data)
+{
+ smp_message_recv(PPC_MSG_DEBUGGER_BREAK);
+ return IRQ_HANDLED;
+}
+
+static irq_handler_t smp_ipi_action[] = {
+ [PPC_MSG_CALL_FUNCTION] = call_function_action,
+ [PPC_MSG_RESCHEDULE] = reschedule_action,
+ [PPC_MSG_CALL_FUNC_SINGLE] = call_function_single_action,
+ [PPC_MSG_DEBUGGER_BREAK] = debug_ipi_action,
+};
+
+const char *smp_ipi_name[] = {
+ [PPC_MSG_CALL_FUNCTION] = "ipi call function",
+ [PPC_MSG_RESCHEDULE] = "ipi reschedule",
+ [PPC_MSG_CALL_FUNC_SINGLE] = "ipi call function single",
+ [PPC_MSG_DEBUGGER_BREAK] = "ipi debugger",
+};
+
+/* optional function to request ipi, for controllers with >= 4 ipis */
+int smp_request_message_ipi(int virq, int msg)
+{
+ int err;
+
+ if (msg < 0 || msg > PPC_MSG_DEBUGGER_BREAK) {
+ return -EINVAL;
+ }
+#if !defined(CONFIG_DEBUGGER) && !defined(CONFIG_KEXEC)
+ if (msg == PPC_MSG_DEBUGGER_BREAK) {
+ return 1;
+ }
+#endif
+ err = request_irq(virq, smp_ipi_action[msg], IRQF_DISABLED|IRQF_PERCPU,
+ smp_ipi_name[msg], 0);
+ WARN(err < 0, "unable to request_irq %d for %s (rc %d)\n",
+ virq, smp_ipi_name[msg], err);
+
+ return err;
+}
+
void smp_send_reschedule(int cpu)
{
if (likely(smp_ops))