[PATCH 4/11] ia64: convert to generic helpers for IPI function calls

Jens Axboe
2008-04-22T07:58:31Z

This converts ia64 to use the new helpers for smp_call_function() and
friends, and adds support for smp_call_function_single().

Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
---
arch/ia64/Kconfig | 5 +
arch/ia64/kernel/smp.c | 239 +++---------------------------------------------
include/asm-ia64/smp.h | 3 -
3 files changed, 20 insertions(+), 227 deletions(-)

diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
index ed21737..e09ab05 100644
--- a/arch/ia64/Kconfig
+++ b/arch/ia64/Kconfig
@@ -51,6 +51,11 @@ config GENERIC_LOCKBREAK
default y
depends on SMP && PREEMPT

+config GENERIC_SMP_HELPERS
+ bool
+ depends on SMP
+ default y
+
config RWSEM_XCHGADD_ALGORITHM
bool
default y
diff --git a/arch/ia64/kernel/smp.c b/arch/ia64/kernel/smp.c
index 9a9d4c4..c5dcd03 100644
--- a/arch/ia64/kernel/smp.c
+++ b/arch/ia64/kernel/smp.c
@@ -60,25 +60,9 @@ static struct local_tlb_flush_counts {

static DEFINE_PER_CPU(unsigned int, shadow_flush_counts[NR_CPUS]) ____cacheline_aligned;

-
-/*
- * Structure and data for smp_call_function(). This is designed to minimise static memory
- * requirements. It also looks cleaner.
- */
-static __cacheline_aligned DEFINE_SPINLOCK(call_lock);
-
-struct call_data_struct {
- void (*func) (void *info);
- void *info;
- long wait;
- atomic_t started;
- atomic_t finished;
-};
-
-static volatile struct call_data_struct *call_data;
-
#define IPI_CALL_FUNC 0
#define IPI_CPU_STOP 1
+#define IPI_CALL_FUNC_SINGLE 2
#define IPI_KDUMP_CPU_STOP 3

/* This needs to be cacheline aligned because it is written to by *other* CPUs. */
@@ -89,13 +73,13 @@ extern void cpu_halt (void);
void
lock_ipi_calllock(void)
{
- spin_lock_irq(&call_lock);
+ spin_lock_irq(&call_function_lock);
}

void
unlock_ipi_calllock(void)
{
- spin_unlock_irq(&call_lock);
+ spin_unlock_irq(&call_function_lock);
}

static void
@@ -139,32 +123,12 @@ handle_IPI (int irq, void *dev_id)

switch (which) {
case IPI_CALL_FUNC:
- {
- struct call_data_struct *data;
- void (*func)(void *info);
- void *info;
- int wait;
-
- /* release the 'pointer lock' */
- data = (struct call_data_struct *) call_data;
- func = data->func;
- info = data->info;
- wait = data->wait;
-
- mb();
- atomic_inc(&data->started);
- /*
- * At this point the structure may be gone unless
- * wait is true.
- */
- (*func)(info);
-
- /* Notify the sending CPU that the task is done. */
- mb();
- if (wait)
- atomic_inc(&data->finished);
- }
- break;
+ generic_smp_call_function_interrupt();
+ break;
+
+ case IPI_CALL_FUNC_SINGLE:
+ generic_smp_call_function_single_interrupt();
+ break;

case IPI_CPU_STOP:
stop_this_cpu();
@@ -185,6 +149,8 @@ handle_IPI (int irq, void *dev_id)
return IRQ_HANDLED;
}

+
+
/*
* Called with preemption disabled.
*/
@@ -358,190 +324,15 @@ smp_flush_tlb_mm (struct mm_struct *mm)
on_each_cpu((void (*)(void *))local_finish_flush_tlb_mm, mm, 1, 1);
}

-/*
- * Run a function on a specific CPU
- * <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 until function has completed on other CPUs.
- * [RETURNS] 0 on success, else a negative status code.
- *
- * Does not return until the remote CPU is nearly ready to execute <func>
- * or is or has executed.
- */
-
-int
-smp_call_function_single (int cpuid, void (*func) (void *info), void *info, int nonatomic,
- int wait)
-{
- struct call_data_struct data;
- int cpus = 1;
- int me = get_cpu(); /* prevent preemption and reschedule on another processor */
-
- if (cpuid == me) {
- local_irq_disable();
- func(info);
- local_irq_enable();
- put_cpu();
- return 0;
- }
-
- data.func = func;
- data.info = info;
- atomic_set(&data.started, 0);
- data.wait = wait;
- if (wait)
- atomic_set(&data.finished, 0);
-
- spin_lock_bh(&call_lock);
-
- call_data = &data;
- mb(); /* ensure store to call_data precedes setting of IPI_CALL_FUNC */
- send_IPI_single(cpuid, IPI_CALL_FUNC);
-
- /* Wait for response */
- while (atomic_read(&data.started) != cpus)
- cpu_relax();
-
- if (wait)
- while (atomic_read(&data.finished) != cpus)
- cpu_relax();
- call_data = NULL;
-
- spin_unlock_bh(&call_lock);
- put_cpu();
- return 0;
-}
-EXPORT_SYMBOL(smp_call_function_single);
-
-/**
- * smp_call_function_mask(): Run a function on a set of other CPUs.
- * <mask> The set of cpus to run on. Must not include the current cpu.
- * <func> The function to run. This must be fast and non-blocking.
- * <info> An arbitrary pointer to pass to the function.
- * <wait> If true, wait (atomically) until function
- * has completed on other CPUs.
- *
- * Returns 0 on success, else a negative status code.
- *
- * If @wait is true, then returns once @func has returned; otherwise
- * it returns just before the target cpu calls @func.
- *
- * You must not call this function with disabled interrupts or from a
- * hardware interrupt handler or from a bottom half handler.
- */
-int smp_call_function_mask(cpumask_t mask,
- void (*func)(void *), void *info,
- int wait)
+void arch_send_call_function_single_ipi(int cpu)
{
- struct call_data_struct data;
- cpumask_t allbutself;
- int cpus;
-
- spin_lock(&call_lock);
- allbutself = cpu_online_map;
- cpu_clear(smp_processor_id(), allbutself);
-
- cpus_and(mask, mask, allbutself);
- cpus = cpus_weight(mask);
- if (!cpus) {
- spin_unlock(&call_lock);
- 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);
-
- call_data = &data;
- mb(); /* ensure store to call_data precedes setting of IPI_CALL_FUNC*/
-
- /* Send a message to other CPUs */
- if (cpus_equal(mask, allbutself))
- send_IPI_allbutself(IPI_CALL_FUNC);
- else
- send_IPI_mask(mask, IPI_CALL_FUNC);
-
- /* Wait for response */
- while (atomic_read(&data.started) != cpus)
- cpu_relax();
-
- if (wait)
- while (atomic_read(&data.finished) != cpus)
- cpu_relax();
- call_data = NULL;
-
- spin_unlock(&call_lock);
- return 0;
-
+ send_IPI_single(cpu, IPI_CALL_FUNC_SINGLE);
}
-EXPORT_SYMBOL(smp_call_function_mask);

-/*
- * this function sends a 'generic call function' IPI to all other CPUs
- * in the system.
- */
-
-/*
- * [SUMMARY] 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.
- * <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.
- *
- * You must not call this function with disabled interrupts or from a
- * hardware interrupt handler or from a bottom half handler.
- */
-int
-smp_call_function (void (*func) (void *info), void *info, int nonatomic, int wait)
+void arch_send_call_function_ipi(cpumask_t mask)
{
- struct call_data_struct data;
- int cpus;
-
- spin_lock(&call_lock);
- cpus = num_online_cpus() - 1;
- if (!cpus) {
- spin_unlock(&call_lock);
- 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);
-
- call_data = &data;
- mb(); /* ensure store to call_data precedes setting of IPI_CALL_FUNC */
- send_IPI_allbutself(IPI_CALL_FUNC);
-
- /* Wait for response */
- while (atomic_read(&data.started) != cpus)
- cpu_relax();
-
- if (wait)
- while (atomic_read(&data.finished) != cpus)
- cpu_relax();
- call_data = NULL;
-
- spin_unlock(&call_lock);
- return 0;
+ send_IPI_mask(mask, IPI_CALL_FUNC);
}
-EXPORT_SYMBOL(smp_call_function);

/*
* this function calls the 'stop' function on all other CPUs in the system.
diff --git a/include/asm-ia64/smp.h b/include/asm-ia64/smp.h
index ec5f355..4fa733d 100644
--- a/include/asm-ia64/smp.h
+++ b/include/asm-ia64/smp.h
@@ -38,9 +38,6 @@ ia64_get_lid (void)
return lid.f.id << 8 | lid.f.eid;
}

-extern int smp_call_function_mask(cpumask_t mask, void (*func)(void *),
- void *info, int wait);
-
#define hard_smp_processor_id() ia64_get_lid()

#ifdef CONFIG_SMP
--
1.5.5.49.gf43e2