parisc: convert to generic helpers for IPI function calls

This converts parisc to use the new helpers for smp_call_function() and
friends, and adds support for smp_call_function_single(). Tested by
Kyle, seems to work.

Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Grant Grundler <grundler@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2 files changed, 22 insertions, 113 deletions

diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig
index bc7a19da6245..a7d4fd353c2b 100644
--- a/arch/parisc/Kconfig
+++ b/arch/parisc/Kconfig
@@ -199,6 +199,7 @@ endchoice
 
 config SMP
         bool "Symmetric multi-processing support"
+        select USE_GENERIC_SMP_HELPERS
         ---help---
           This enables support for systems with more than one CPU. If you have
           a system with only one CPU, like most personal computers, say N. If
diff --git a/arch/parisc/kernel/smp.c b/arch/parisc/kernel/smp.c
index 85fc7754ec25..126105c76a44 100644
--- a/arch/parisc/kernel/smp.c
+++ b/arch/parisc/kernel/smp.c
@@ -84,19 +84,11 @@ EXPORT_SYMBOL(cpu_possible_map);
 
 DEFINE_PER_CPU(spinlock_t, ipi_lock) = SPIN_LOCK_UNLOCKED;
 
-struct smp_call_struct {
-        void (*func) (void *info);
-        void *info;
-        long wait;
-        atomic_t unstarted_count;
-        atomic_t unfinished_count;
-};
-static volatile struct smp_call_struct *smp_call_function_data;
-
 enum ipi_message_type {
         IPI_NOP=0,
         IPI_RESCHEDULE=1,
         IPI_CALL_FUNC,
+        IPI_CALL_FUNC_SINGLE,
         IPI_CPU_START,
         IPI_CPU_STOP,
         IPI_CPU_TEST
@@ -187,33 +179,12 @@ ipi_interrupt(int irq, void *dev_id)
 
                         case IPI_CALL_FUNC:
                                 smp_debug(100, KERN_DEBUG "CPU%d IPI_CALL_FUNC\n", this_cpu);
-                                {
-                                        volatile struct smp_call_struct *data;
-                                        void (*func)(void *info);
-                                        void *info;
-                                        int wait;
-
-                                        data = smp_call_function_data;
-                                        func = data->func;
-                                        info = data->info;
-                                        wait = data->wait;
-
-                                        mb();
-                                        atomic_dec ((atomic_t *)&data->unstarted_count);
-
-                                        /* At this point, *data can't
-                                         * be relied upon.
-                                         */
-
-                                        (*func)(info);
-
-                                        /* Notify the sending CPU that the
-                                         * task is done.
-                                         */
-                                        mb();
-                                        if (wait)
-                                                atomic_dec ((atomic_t *)&data->unfinished_count);
-                                }
+                                generic_smp_call_function_interrupt();
+                                break;
+
+                        case IPI_CALL_FUNC_SINGLE:
+                                smp_debug(100, KERN_DEBUG "CPU%d IPI_CALL_FUNC_SINGLE\n", this_cpu);
+                                generic_smp_call_function_single_interrupt();
                                 break;
 
                         case IPI_CPU_START:
@@ -256,6 +227,14 @@ ipi_send(int cpu, enum ipi_message_type op)
         spin_unlock_irqrestore(lock, flags);
 }
 
+static void
+send_IPI_mask(cpumask_t mask, enum ipi_message_type op)
+{
+        int cpu;
+
+        for_each_cpu_mask(cpu, mask)
+                ipi_send(cpu, op);
+}
 
 static inline void
 send_IPI_single(int dest_cpu, enum ipi_message_type op)
@@ -295,86 +274,15 @@ smp_send_all_nop(void)
         send_IPI_allbutself(IPI_NOP);
 }
 
-
-/**
- * Run a function on all other CPUs.
- *  <func>      The function to run. This must be fast and non-blocking.
- *  <info>      An arbitrary pointer to pass to the function.
- *  <retry>     If true, keep retrying until ready.
- *  <wait>      If true, wait 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 have executed.
- */
-
-int
-smp_call_function (void (*func) (void *info), void *info, int retry, int wait)
+void arch_send_call_function_ipi(cpumask_t mask)
 {
-        struct smp_call_struct data;
-        unsigned long timeout;
-        static DEFINE_SPINLOCK(lock);
-        int retries = 0;
-
-        if (num_online_cpus() < 2)
-                return 0;
-
-        /* Can deadlock when called with interrupts disabled */
-        WARN_ON(irqs_disabled());
-
-        /* can also deadlock if IPIs are disabled */
-        WARN_ON((get_eiem() & (1UL<<(CPU_IRQ_MAX - IPI_IRQ))) == 0);
-
-        
-        data.func = func;
-        data.info = info;
-        data.wait = wait;
-        atomic_set(&data.unstarted_count, num_online_cpus() - 1);
-        atomic_set(&data.unfinished_count, num_online_cpus() - 1);
-
-        if (retry) {
-                spin_lock (&lock);
-                while (smp_call_function_data != 0)
-                        barrier();
-        }
-        else {
-                spin_lock (&lock);
-                if (smp_call_function_data) {
-                        spin_unlock (&lock);
-                        return -EBUSY;
-                }
-        }
-
-        smp_call_function_data = &data;
-        spin_unlock (&lock);
-        
-        /*  Send a message to all other CPUs and wait for them to respond  */
-        send_IPI_allbutself(IPI_CALL_FUNC);
-
- retry:
-        /*  Wait for response  */
-        timeout = jiffies + HZ;
-        while ( (atomic_read (&data.unstarted_count) > 0) &&
-                time_before (jiffies, timeout) )
-                barrier ();
-
-        if (atomic_read (&data.unstarted_count) > 0) {
-                printk(KERN_CRIT "SMP CALL FUNCTION TIMED OUT! (cpu=%d), try %d\n",
-                      smp_processor_id(), ++retries);
-                goto retry;
-        }
-        /* We either got one or timed out. Release the lock */
-
-        mb();
-        smp_call_function_data = NULL;
-
-        while (wait && atomic_read (&data.unfinished_count) > 0)
-                        barrier ();
-
-        return 0;
+        send_IPI_mask(mask, IPI_CALL_FUNC);
 }
 
-EXPORT_SYMBOL(smp_call_function);
+void arch_send_call_function_single_ipi(int cpu)
+{
+        send_IPI_single(cpu, IPI_CALL_FUNC_SINGLE);
+}
 
 /*
  * Flush all other CPU's tlb and then mine.  Do this with on_each_cpu()