powerpc: convert to generic helpers for IPI function calls
authorJens Axboe <jens.axboe@oracle.com>
Thu, 26 Jun 2008 09:22:13 +0000 (11:22 +0200)
committerJens Axboe <jens.axboe@oracle.com>
Thu, 26 Jun 2008 09:22:13 +0000 (11:22 +0200)
This converts ppc to use the new helpers for smp_call_function() and
friends, and adds support for smp_call_function_single().

ppc loses the timeout functionality of smp_call_function_mask() with
this change, as the generic code does not provide that.

Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
arch/powerpc/Kconfig
arch/powerpc/kernel/smp.c
arch/powerpc/platforms/cell/interrupt.c
arch/powerpc/platforms/ps3/smp.c
arch/powerpc/platforms/pseries/xics.c
arch/powerpc/sysdev/mpic.c
include/asm-powerpc/smp.h

index 3934e26..852d40c 100644 (file)
@@ -110,6 +110,7 @@ config PPC
        select HAVE_KPROBES
        select HAVE_KRETPROBES
        select HAVE_LMB
+       select USE_GENERIC_SMP_HELPERS if SMP
 
 config EARLY_PRINTK
        bool
index 1457aa0..37a5ab4 100644 (file)
@@ -72,12 +72,8 @@ struct smp_ops_t *smp_ops;
 
 static volatile unsigned int cpu_callin_map[NR_CPUS];
 
-void smp_call_function_interrupt(void);
-
 int smt_enabled_at_boot = 1;
 
-static int ipi_fail_ok;
-
 static void (*crash_ipi_function_ptr)(struct pt_regs *) = NULL;
 
 #ifdef CONFIG_PPC64
@@ -99,12 +95,15 @@ void smp_message_recv(int msg)
 {
        switch(msg) {
        case PPC_MSG_CALL_FUNCTION:
-               smp_call_function_interrupt();
+               generic_smp_call_function_interrupt();
                break;
        case PPC_MSG_RESCHEDULE:
                /* XXX Do we have to do this? */
                set_need_resched();
                break;
+       case PPC_MSG_CALL_FUNC_SINGLE:
+               generic_smp_call_function_single_interrupt();
+               break;
        case PPC_MSG_DEBUGGER_BREAK:
                if (crash_ipi_function_ptr) {
                        crash_ipi_function_ptr(get_irq_regs());
@@ -128,6 +127,19 @@ void smp_send_reschedule(int cpu)
                smp_ops->message_pass(cpu, PPC_MSG_RESCHEDULE);
 }
 
+void arch_send_call_function_single_ipi(int cpu)
+{
+       smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNC_SINGLE);
+}
+
+void arch_send_call_function_ipi(cpumask_t mask)
+{
+       unsigned int cpu;
+
+       for_each_cpu_mask(cpu, mask)
+               smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNCTION);
+}
+
 #ifdef CONFIG_DEBUGGER
 void smp_send_debugger_break(int cpu)
 {
@@ -154,215 +166,9 @@ static void stop_this_cpu(void *dummy)
                ;
 }
 
-/*
- * Structure and data for smp_call_function(). This is designed to minimise
- * static memory requirements. It also looks cleaner.
- * Stolen from the i386 version.
- */
-static  __cacheline_aligned_in_smp DEFINE_SPINLOCK(call_lock);
-
-static struct call_data_struct {
-       void (*func) (void *info);
-       void *info;
-       atomic_t started;
-       atomic_t finished;
-       int wait;
-} *call_data;
-
-/* delay of at least 8 seconds */
-#define SMP_CALL_TIMEOUT       8
-
-/*
- * These functions send a 'generic call function' IPI to other online
- * CPUS in the system.
- *
- * [SUMMARY] Run a function on other CPUs.
- * <func> The function to run. This must be fast and non-blocking.
- * <info> An arbitrary pointer to pass to the function.
- * <nonatomic> currently unused.
- * <wait> If true, wait (atomically) until function has completed on other CPUs.
- * [RETURNS] 0 on success, else a negative status code. Does not return until
- * remote CPUs are nearly ready to execute <<func>> or are or have executed.
- * <map> is a cpu map of the cpus to send IPI to.
- *
- * You must not call this function with disabled interrupts or from a
- * hardware interrupt handler or from a bottom half handler.
- */
-static int __smp_call_function_map(void (*func) (void *info), void *info,
-                                  int nonatomic, int wait, cpumask_t map)
-{
-       struct call_data_struct data;
-       int ret = -1, num_cpus;
-       int cpu;
-       u64 timeout;
-
-       if (unlikely(smp_ops == NULL))
-               return ret;
-
-       data.func = func;
-       data.info = info;
-       atomic_set(&data.started, 0);
-       data.wait = wait;
-       if (wait)
-               atomic_set(&data.finished, 0);
-
-       /* remove 'self' from the map */
-       if (cpu_isset(smp_processor_id(), map))
-               cpu_clear(smp_processor_id(), map);
-
-       /* sanity check the map, remove any non-online processors. */
-       cpus_and(map, map, cpu_online_map);
-
-       num_cpus = cpus_weight(map);
-       if (!num_cpus)
-               goto done;
-
-       call_data = &data;
-       smp_wmb();
-       /* Send a message to all CPUs in the map */
-       for_each_cpu_mask(cpu, map)
-               smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNCTION);
-
-       timeout = get_tb() + (u64) SMP_CALL_TIMEOUT * tb_ticks_per_sec;
-
-       /* Wait for indication that they have received the message */
-       while (atomic_read(&data.started) != num_cpus) {
-               HMT_low();
-               if (get_tb() >= timeout) {
-                       printk("smp_call_function on cpu %d: other cpus not "
-                               "responding (%d)\n", smp_processor_id(),
-                               atomic_read(&data.started));
-                       if (!ipi_fail_ok)
-                               debugger(NULL);
-                       goto out;
-               }
-       }
-
-       /* optionally wait for the CPUs to complete */
-       if (wait) {
-               while (atomic_read(&data.finished) != num_cpus) {
-                       HMT_low();
-                       if (get_tb() >= timeout) {
-                               printk("smp_call_function on cpu %d: other "
-                                       "cpus not finishing (%d/%d)\n",
-                                       smp_processor_id(),
-                                       atomic_read(&data.finished),
-                                       atomic_read(&data.started));
-                               debugger(NULL);
-                               goto out;
-                       }
-               }
-       }
-
- done:
-       ret = 0;
-
- out:
-       call_data = NULL;
-       HMT_medium();
-       return ret;
-}
-
-static int __smp_call_function(void (*func)(void *info), void *info,
-                              int nonatomic, int wait)
-{
-       int ret;
-       spin_lock(&call_lock);
-       ret =__smp_call_function_map(func, info, nonatomic, wait,
-                                      cpu_online_map);
-       spin_unlock(&call_lock);
-       return ret;
-}
-
-int smp_call_function(void (*func) (void *info), void *info, int nonatomic,
-                       int wait)
-{
-       /* Can deadlock when called with interrupts disabled */
-       WARN_ON(irqs_disabled());
-
-       return __smp_call_function(func, info, nonatomic, wait);
-}
-EXPORT_SYMBOL(smp_call_function);
-
-int smp_call_function_single(int cpu, void (*func) (void *info), void *info,
-                            int nonatomic, int wait)
-{
-       cpumask_t map = CPU_MASK_NONE;
-       int ret = 0;
-
-       /* Can deadlock when called with interrupts disabled */
-       WARN_ON(irqs_disabled());
-
-       if (!cpu_online(cpu))
-               return -EINVAL;
-
-       cpu_set(cpu, map);
-       if (cpu != get_cpu()) {
-               spin_lock(&call_lock);
-               ret = __smp_call_function_map(func, info, nonatomic, wait, map);
-               spin_unlock(&call_lock);
-       } else {
-               local_irq_disable();
-               func(info);
-               local_irq_enable();
-       }
-       put_cpu();
-       return ret;
-}
-EXPORT_SYMBOL(smp_call_function_single);
-
 void smp_send_stop(void)
 {
-       int nolock;
-
-       /* It's OK to fail sending the IPI, since the alternative is to
-        * be stuck forever waiting on the other CPU to take the interrupt.
-        *
-        * It's better to at least continue and go through reboot, since this
-        * function is usually called at panic or reboot time in the first
-        * place.
-        */
-       ipi_fail_ok = 1;
-
-       /* Don't deadlock in case we got called through panic */
-       nolock = !spin_trylock(&call_lock);
-       __smp_call_function_map(stop_this_cpu, NULL, 1, 0, cpu_online_map);
-       if (!nolock)
-               spin_unlock(&call_lock);
-}
-
-void smp_call_function_interrupt(void)
-{
-       void (*func) (void *info);
-       void *info;
-       int wait;
-
-       /* call_data will be NULL if the sender timed out while
-        * waiting on us to receive the call.
-        */
-       if (!call_data)
-               return;
-
-       func = call_data->func;
-       info = call_data->info;
-       wait = call_data->wait;
-
-       if (!wait)
-               smp_mb__before_atomic_inc();
-
-       /*
-        * Notify initiating CPU that I've grabbed the data and am
-        * about to execute the function
-        */
-       atomic_inc(&call_data->started);
-       /*
-        * At this point the info structure may be out of scope unless wait==1
-        */
-       (*func)(info);
-       if (wait) {
-               smp_mb__before_atomic_inc();
-               atomic_inc(&call_data->finished);
-       }
+       smp_call_function(stop_this_cpu, NULL, 0, 0);
 }
 
 extern struct gettimeofday_struct do_gtod;
@@ -596,9 +402,9 @@ int __devinit start_secondary(void *unused)
 
        secondary_cpu_time_init();
 
-       spin_lock(&call_lock);
+       ipi_call_lock();
        cpu_set(cpu, cpu_online_map);
-       spin_unlock(&call_lock);
+       ipi_call_unlock();
 
        local_irq_enable();
 
index 5bf7df1..2d5bb22 100644 (file)
@@ -218,6 +218,7 @@ void iic_request_IPIs(void)
 {
        iic_request_ipi(PPC_MSG_CALL_FUNCTION, "IPI-call");
        iic_request_ipi(PPC_MSG_RESCHEDULE, "IPI-resched");
+       iic_request_ipi(PPC_MSG_CALL_FUNC_SINGLE, "IPI-call-single");
 #ifdef CONFIG_DEBUGGER
        iic_request_ipi(PPC_MSG_DEBUGGER_BREAK, "IPI-debug");
 #endif /* CONFIG_DEBUGGER */
index f0b12f2..a0927a3 100644 (file)
@@ -105,9 +105,10 @@ static void __init ps3_smp_setup_cpu(int cpu)
         * to index needs to be setup.
         */
 
-       BUILD_BUG_ON(PPC_MSG_CALL_FUNCTION  != 0);
-       BUILD_BUG_ON(PPC_MSG_RESCHEDULE     != 1);
-       BUILD_BUG_ON(PPC_MSG_DEBUGGER_BREAK != 3);
+       BUILD_BUG_ON(PPC_MSG_CALL_FUNCTION    != 0);
+       BUILD_BUG_ON(PPC_MSG_RESCHEDULE       != 1);
+       BUILD_BUG_ON(PPC_MSG_CALL_FUNC_SINGLE != 2);
+       BUILD_BUG_ON(PPC_MSG_DEBUGGER_BREAK   != 3);
 
        for (i = 0; i < MSG_COUNT; i++) {
                result = ps3_event_receive_port_setup(cpu, &virqs[i]);
index ebebc28..0fc830f 100644 (file)
@@ -383,13 +383,11 @@ static irqreturn_t xics_ipi_dispatch(int cpu)
                        mb();
                        smp_message_recv(PPC_MSG_RESCHEDULE);
                }
-#if 0
-               if (test_and_clear_bit(PPC_MSG_MIGRATE_TASK,
+               if (test_and_clear_bit(PPC_MSG_CALL_FUNC_SINGLE,
                                       &xics_ipi_message[cpu].value)) {
                        mb();
-                       smp_message_recv(PPC_MSG_MIGRATE_TASK);
+                       smp_message_recv(PPC_MSG_CALL_FUNC_SINGLE);
                }
-#endif
 #if defined(CONFIG_DEBUGGER) || defined(CONFIG_KEXEC)
                if (test_and_clear_bit(PPC_MSG_DEBUGGER_BREAK,
                                       &xics_ipi_message[cpu].value)) {
index 7680001..6c90c95 100644 (file)
@@ -1494,7 +1494,7 @@ void mpic_request_ipis(void)
        static char *ipi_names[] = {
                "IPI0 (call function)",
                "IPI1 (reschedule)",
-               "IPI2 (unused)",
+               "IPI2 (call function single)",
                "IPI3 (debugger break)",
        };
        BUG_ON(mpic == NULL);
index 505f35b..c663a1f 100644 (file)
@@ -67,10 +67,7 @@ DECLARE_PER_CPU(cpumask_t, cpu_sibling_map);
  * in /proc/interrupts will be wrong!!! --Troy */
 #define PPC_MSG_CALL_FUNCTION   0
 #define PPC_MSG_RESCHEDULE      1
-/* This is unused now */
-#if 0
-#define PPC_MSG_MIGRATE_TASK    2
-#endif
+#define PPC_MSG_CALL_FUNC_SINGLE       2
 #define PPC_MSG_DEBUGGER_BREAK  3
 
 void smp_init_iSeries(void);
@@ -117,6 +114,9 @@ extern void smp_generic_take_timebase(void);
 
 extern struct smp_ops_t *smp_ops;
 
+extern void arch_send_call_function_single_ipi(int cpu);
+extern void arch_send_call_function_ipi(cpumask_t mask);
+
 #endif /* __ASSEMBLY__ */
 
 #endif /* __KERNEL__ */