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 1866cec4f9677b5fc995e754cea3ed6936d7ec57..c25f73d1d84203e0393d26d5da07e390c79417e5 100644 (file)
--- a/arch/powerpc/include/asm/smp.h
+++ b/arch/powerpc/include/asm/smp.h
@@ -81,6 +81,13 @@ extern int cpu_to_core_id(int cpu);
 #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 ff9f7010097d1568943329a15d8c04458beddc4c..a59d8d72bb97c0c7553e4e947f325b956556c8b4 100644 (file)
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -123,6 +123,65 @@ void smp_message_recv(int msg)
        }
 }
 
+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))