mips: convert to generic helpers for IPI function calls

This converts mips to use the new helpers for smp_call_function() and
friends, and adds support for smp_call_function_single(). Not tested,
but it compiles.

mips shares the same IPI for smp_call_function() and
smp_call_function_single(), since not all mips platforms have enough
available IPIs to support seperate setups.

Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index e5a7c5d96364f73f5cf700a9ac70d9ee67d3bda8..ea70d5a225ca62642cf66ab8bd1c574fce0b657d 100644 (file)
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -1763,6 +1763,7 @@ config SMP
        bool "Multi-Processing support"
        depends on SYS_SUPPORTS_SMP
        select IRQ_PER_CPU
+       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/mips/kernel/smp.c b/arch/mips/kernel/smp.c
index cdf87a9dd4bafe6ea381794bca5a2d6b2e97877d..c75b26cb61dfa26f866ec2d7a0399b668cf01750 100644 (file)
--- a/arch/mips/kernel/smp.c
+++ b/arch/mips/kernel/smp.c
@@ -131,148 +131,29 @@ asmlinkage __cpuinit void start_secondary(void)
        cpu_idle();
 }
 
-DEFINE_SPINLOCK(smp_call_lock);
-
-struct call_data_struct *call_data;
-
-/*
- * Run a function on all other CPUs.
- *
- *  <mask>     cpuset_t of all processors to run the function on.
- *  <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 are or have executed.
- *
- * You must not call this function with disabled interrupts or from a
- * hardware interrupt handler or from a bottom half handler:
- *
- * CPU A                               CPU B
- * Disable interrupts
- *                                     smp_call_function()
- *                                     Take call_lock
- *                                     Send IPIs
- *                                     Wait for all cpus to acknowledge IPI
- *                                     CPU A has not responded, spin waiting
- *                                     for cpu A to respond, holding call_lock
- * smp_call_function()
- * Spin waiting for call_lock
- * Deadlock                            Deadlock
- */
-int smp_call_function_mask(cpumask_t mask, void (*func) (void *info),
-       void *info, int retry, int wait)
+void arch_send_call_function_ipi(cpumask_t mask)
 {
-       struct call_data_struct data;
-       int cpu = smp_processor_id();
-       int cpus;
-
-       /*
-        * Can die spectacularly if this CPU isn't yet marked online
-        */
-       BUG_ON(!cpu_online(cpu));
-
-       cpu_clear(cpu, mask);
-       cpus = cpus_weight(mask);
-       if (!cpus)
-               return 0;
-
-       /* Can deadlock when called with interrupts disabled */
-       WARN_ON(irqs_disabled());
-
-       data.func = func;
-       data.info = info;
-       atomic_set(&data.started, 0);
-       data.wait = wait;
-       if (wait)
-               atomic_set(&data.finished, 0);
-
-       spin_lock(&smp_call_lock);
-       call_data = &data;
-       smp_mb();
-
-       /* Send a message to all other CPUs and wait for them to respond */
        mp_ops->send_ipi_mask(mask, SMP_CALL_FUNCTION);
-
-       /* Wait for response */
-       /* FIXME: lock-up detection, backtrace on lock-up */
-       while (atomic_read(&data.started) != cpus)
-               barrier();
-
-       if (wait)
-               while (atomic_read(&data.finished) != cpus)
-                       barrier();
-       call_data = NULL;
-       spin_unlock(&smp_call_lock);
-
-       return 0;
 }
 
-int smp_call_function(void (*func) (void *info), void *info, int retry,
-       int wait)
+/*
+ * We reuse the same vector for the single IPI
+ */
+void arch_send_call_function_single_ipi(int cpu)
 {
-       return smp_call_function_mask(cpu_online_map, func, info, retry, wait);
+       mp_ops->send_ipi_mask(cpumask_of_cpu(cpu), SMP_CALL_FUNCTION);
 }
-EXPORT_SYMBOL(smp_call_function);
 
+/*
+ * Call into both interrupt handlers, as we share the IPI for them
+ */
 void smp_call_function_interrupt(void)
 {
-       void (*func) (void *info) = call_data->func;
-       void *info = call_data->info;
-       int wait = call_data->wait;
-
-       /*
-        * Notify initiating CPU that I've grabbed the data and am
-        * about to execute the function.
-        */
-       smp_mb();
-       atomic_inc(&call_data->started);
-
-       /*
-        * At this point the info structure may be out of scope unless wait==1.
-        */
        irq_enter();
-       (*func)(info);
+       generic_smp_call_function_single_interrupt();
+       generic_smp_call_function_interrupt();
        irq_exit();
-
-       if (wait) {
-               smp_mb();
-               atomic_inc(&call_data->finished);
-       }
-}
-
-int smp_call_function_single(int cpu, void (*func) (void *info), void *info,
-                            int retry, int wait)
-{
-       int ret, me;
-
-       /*
-        * Can die spectacularly if this CPU isn't yet marked online
-        */
-       if (!cpu_online(cpu))
-               return 0;
-
-       me = get_cpu();
-       BUG_ON(!cpu_online(me));
-
-       if (cpu == me) {
-               local_irq_disable();
-               func(info);
-               local_irq_enable();
-               put_cpu();
-               return 0;
-       }
-
-       ret = smp_call_function_mask(cpumask_of_cpu(cpu), func, info, retry,
-                                    wait);
-
-       put_cpu();
-       return 0;
 }
-EXPORT_SYMBOL(smp_call_function_single);
 
 static void stop_this_cpu(void *dummy)
 {

diff --git a/arch/mips/kernel/smtc.c b/arch/mips/kernel/smtc.c
index 3e863186cd222944fcbf9b441dc7e10f140fcb18..a516286532ab092637cab432cd8742a0800e6fb0 100644 (file)
--- a/arch/mips/kernel/smtc.c
+++ b/arch/mips/kernel/smtc.c
@@ -877,7 +877,6 @@ static void ipi_resched_interrupt(void)
        /* Return from interrupt should be enough to cause scheduler check */
 }
 
-
 static void ipi_call_interrupt(void)
 {
        /* Invoke generic function invocation code in smp.c */

diff --git a/include/asm-mips/smp.h b/include/asm-mips/smp.h
index 84fef1aeec0c314f13e1ad77705aa2e412da1ea2..0ff5b523ea77d8f6a5b7b2337969e414ce5ddaa8 100644 (file)
--- a/include/asm-mips/smp.h
+++ b/include/asm-mips/smp.h
@@ -35,16 +35,6 @@ extern int __cpu_logical_map[NR_CPUS];
 
 #define NO_PROC_ID     (-1)
 
-struct call_data_struct {
-       void            (*func)(void *);
-       void            *info;
-       atomic_t        started;
-       atomic_t        finished;
-       int             wait;
-};
-
-extern struct call_data_struct *call_data;
-
 #define SMP_RESCHEDULE_YOURSELF        0x1     /* XXX braindead */
 #define SMP_CALL_FUNCTION      0x2
 
@@ -67,4 +57,7 @@ static inline void smp_send_reschedule(int cpu)
 
 extern asmlinkage void smp_call_function_interrupt(void);
 
+extern void arch_send_call_function_single_ipi(int cpu);
+extern void arch_send_call_function_ipi(cpumask_t mask);
+
 #endif /* __ASM_SMP_H */