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blackfin: smp: adapt to generic smp helpers
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Replace blackfin ipi message queue with generic smp helper function.

Signed-off-by: Steven Miao <realmz6@gmail.com>
Signed-off-by: Bob Liu <lliubbo@gmail.com>
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Steven Miao authored and Bob Liu committed Sep 7, 2012
1 parent 0d7614f commit 5088846
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Showing 3 changed files with 69 additions and 157 deletions.
1 change: 1 addition & 0 deletions arch/blackfin/Kconfig
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Original file line number Diff line number Diff line change
Expand Up @@ -38,6 +38,7 @@ config BLACKFIN
select GENERIC_ATOMIC64
select GENERIC_IRQ_PROBE
select IRQ_PER_CPU if SMP
select USE_GENERIC_SMP_HELPERS if SMP
select HAVE_NMI_WATCHDOG if NMI_WATCHDOG
select GENERIC_SMP_IDLE_THREAD
select ARCH_USES_GETTIMEOFFSET if !GENERIC_CLOCKEVENTS
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2 changes: 2 additions & 0 deletions arch/blackfin/include/asm/smp.h
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Original file line number Diff line number Diff line change
Expand Up @@ -18,6 +18,8 @@
#define raw_smp_processor_id() blackfin_core_id()

extern void bfin_relocate_coreb_l1_mem(void);
extern void arch_send_call_function_single_ipi(int cpu);
extern void arch_send_call_function_ipi_mask(const struct cpumask *mask);

#if defined(CONFIG_SMP) && defined(CONFIG_ICACHE_FLUSH_L1)
asmlinkage void blackfin_icache_flush_range_l1(unsigned long *ptr);
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223 changes: 66 additions & 157 deletions arch/blackfin/mach-common/smp.c
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Original file line number Diff line number Diff line change
Expand Up @@ -48,10 +48,13 @@ unsigned long blackfin_iflush_l1_entry[NR_CPUS];

struct blackfin_initial_pda __cpuinitdata initial_pda_coreb;

#define BFIN_IPI_TIMER 0
#define BFIN_IPI_RESCHEDULE 1
#define BFIN_IPI_CALL_FUNC 2
#define BFIN_IPI_CPU_STOP 3
enum ipi_message_type {
BFIN_IPI_TIMER,
BFIN_IPI_RESCHEDULE,
BFIN_IPI_CALL_FUNC,
BFIN_IPI_CALL_FUNC_SINGLE,
BFIN_IPI_CPU_STOP,
};

struct blackfin_flush_data {
unsigned long start;
Expand All @@ -60,35 +63,20 @@ struct blackfin_flush_data {

void *secondary_stack;


struct smp_call_struct {
void (*func)(void *info);
void *info;
int wait;
cpumask_t *waitmask;
};

static struct blackfin_flush_data smp_flush_data;

static DEFINE_SPINLOCK(stop_lock);

struct ipi_message {
unsigned long type;
struct smp_call_struct call_struct;
};

/* A magic number - stress test shows this is safe for common cases */
#define BFIN_IPI_MSGQ_LEN 5

/* Simple FIFO buffer, overflow leads to panic */
struct ipi_message_queue {
spinlock_t lock;
struct ipi_data {
unsigned long count;
unsigned long head; /* head of the queue */
struct ipi_message ipi_message[BFIN_IPI_MSGQ_LEN];
unsigned long bits;
};

static DEFINE_PER_CPU(struct ipi_message_queue, ipi_msg_queue);
static DEFINE_PER_CPU(struct ipi_data, bfin_ipi);

static void ipi_cpu_stop(unsigned int cpu)
{
Expand Down Expand Up @@ -129,28 +117,6 @@ static void ipi_flush_icache(void *info)
blackfin_icache_flush_range(fdata->start, fdata->end);
}

static void ipi_call_function(unsigned int cpu, struct ipi_message *msg)
{
int wait;
void (*func)(void *info);
void *info;
func = msg->call_struct.func;
info = msg->call_struct.info;
wait = msg->call_struct.wait;
func(info);
if (wait) {
#ifdef __ARCH_SYNC_CORE_DCACHE
/*
* 'wait' usually means synchronization between CPUs.
* Invalidate D cache in case shared data was changed
* by func() to ensure cache coherence.
*/
resync_core_dcache();
#endif
cpumask_clear_cpu(cpu, msg->call_struct.waitmask);
}
}

/* Use IRQ_SUPPLE_0 to request reschedule.
* When returning from interrupt to user space,
* there is chance to reschedule */
Expand All @@ -172,152 +138,95 @@ void ipi_timer(void)

static irqreturn_t ipi_handler_int1(int irq, void *dev_instance)
{
struct ipi_message *msg;
struct ipi_message_queue *msg_queue;
struct ipi_data *bfin_ipi_data;
unsigned int cpu = smp_processor_id();
unsigned long flags;
unsigned long pending;
unsigned long msg;

platform_clear_ipi(cpu, IRQ_SUPPLE_1);

msg_queue = &__get_cpu_var(ipi_msg_queue);

spin_lock_irqsave(&msg_queue->lock, flags);

while (msg_queue->count) {
msg = &msg_queue->ipi_message[msg_queue->head];
switch (msg->type) {
case BFIN_IPI_TIMER:
ipi_timer();
break;
case BFIN_IPI_RESCHEDULE:
scheduler_ipi();
break;
case BFIN_IPI_CALL_FUNC:
ipi_call_function(cpu, msg);
break;
case BFIN_IPI_CPU_STOP:
ipi_cpu_stop(cpu);
break;
default:
printk(KERN_CRIT "CPU%u: Unknown IPI message 0x%lx\n",
cpu, msg->type);
break;
}
msg_queue->head++;
msg_queue->head %= BFIN_IPI_MSGQ_LEN;
msg_queue->count--;
bfin_ipi_data = &__get_cpu_var(bfin_ipi);

while ((pending = xchg(&bfin_ipi_data->bits, 0)) != 0) {
msg = 0;
do {
msg = find_next_bit(&pending, BITS_PER_LONG, msg + 1);
switch (msg) {
case BFIN_IPI_TIMER:
ipi_timer();
break;
case BFIN_IPI_RESCHEDULE:
scheduler_ipi();
break;
case BFIN_IPI_CALL_FUNC:
generic_smp_call_function_interrupt();
break;

case BFIN_IPI_CALL_FUNC_SINGLE:
generic_smp_call_function_single_interrupt();
break;

case BFIN_IPI_CPU_STOP:
ipi_cpu_stop(cpu);
break;
}
} while (msg < BITS_PER_LONG);

smp_mb();
}
spin_unlock_irqrestore(&msg_queue->lock, flags);
return IRQ_HANDLED;
}

static void ipi_queue_init(void)
static void bfin_ipi_init(void)
{
unsigned int cpu;
struct ipi_message_queue *msg_queue;
struct ipi_data *bfin_ipi_data;
for_each_possible_cpu(cpu) {
msg_queue = &per_cpu(ipi_msg_queue, cpu);
spin_lock_init(&msg_queue->lock);
msg_queue->count = 0;
msg_queue->head = 0;
bfin_ipi_data = &per_cpu(bfin_ipi, cpu);
bfin_ipi_data->bits = 0;
bfin_ipi_data->count = 0;
}
}

static inline void smp_send_message(cpumask_t callmap, unsigned long type,
void (*func) (void *info), void *info, int wait)
void send_ipi(const struct cpumask *cpumask, enum ipi_message_type msg)
{
unsigned int cpu;
struct ipi_message_queue *msg_queue;
struct ipi_message *msg;
unsigned long flags, next_msg;
cpumask_t waitmask; /* waitmask is shared by all cpus */

cpumask_copy(&waitmask, &callmap);
for_each_cpu(cpu, &callmap) {
msg_queue = &per_cpu(ipi_msg_queue, cpu);
spin_lock_irqsave(&msg_queue->lock, flags);
if (msg_queue->count < BFIN_IPI_MSGQ_LEN) {
next_msg = (msg_queue->head + msg_queue->count)
% BFIN_IPI_MSGQ_LEN;
msg = &msg_queue->ipi_message[next_msg];
msg->type = type;
if (type == BFIN_IPI_CALL_FUNC) {
msg->call_struct.func = func;
msg->call_struct.info = info;
msg->call_struct.wait = wait;
msg->call_struct.waitmask = &waitmask;
}
msg_queue->count++;
} else
panic("IPI message queue overflow\n");
spin_unlock_irqrestore(&msg_queue->lock, flags);
struct ipi_data *bfin_ipi_data;
unsigned long flags;

local_irq_save(flags);

for_each_cpu(cpu, cpumask) {
bfin_ipi_data = &per_cpu(bfin_ipi, cpu);
smp_mb();
set_bit(msg, &bfin_ipi_data->bits);
bfin_ipi_data->count++;
platform_send_ipi_cpu(cpu, IRQ_SUPPLE_1);
}

if (wait) {
while (!cpumask_empty(&waitmask))
blackfin_dcache_invalidate_range(
(unsigned long)(&waitmask),
(unsigned long)(&waitmask));
#ifdef __ARCH_SYNC_CORE_DCACHE
/*
* Invalidate D cache in case shared data was changed by
* other processors to ensure cache coherence.
*/
resync_core_dcache();
#endif
}
local_irq_restore(flags);
}

int smp_call_function(void (*func)(void *info), void *info, int wait)
void arch_send_call_function_single_ipi(int cpu)
{
cpumask_t callmap;

preempt_disable();
cpumask_copy(&callmap, cpu_online_mask);
cpumask_clear_cpu(smp_processor_id(), &callmap);
if (!cpumask_empty(&callmap))
smp_send_message(callmap, BFIN_IPI_CALL_FUNC, func, info, wait);

preempt_enable();

return 0;
send_ipi(cpumask_of(cpu), BFIN_IPI_CALL_FUNC_SINGLE);
}
EXPORT_SYMBOL_GPL(smp_call_function);

int smp_call_function_single(int cpuid, void (*func) (void *info), void *info,
int wait)
void arch_send_call_function_ipi_mask(const struct cpumask *mask)
{
unsigned int cpu = cpuid;
cpumask_t callmap;

if (cpu_is_offline(cpu))
return 0;
cpumask_clear(&callmap);
cpumask_set_cpu(cpu, &callmap);

smp_send_message(callmap, BFIN_IPI_CALL_FUNC, func, info, wait);

return 0;
send_ipi(mask, BFIN_IPI_CALL_FUNC);
}
EXPORT_SYMBOL_GPL(smp_call_function_single);

void smp_send_reschedule(int cpu)
{
cpumask_t callmap;
/* simply trigger an ipi */

cpumask_clear(&callmap);
cpumask_set_cpu(cpu, &callmap);

smp_send_message(callmap, BFIN_IPI_RESCHEDULE, NULL, NULL, 0);
send_ipi(cpumask_of(cpu), BFIN_IPI_RESCHEDULE);

return;
}

void smp_send_msg(const struct cpumask *mask, unsigned long type)
{
smp_send_message(*mask, type, NULL, NULL, 0);
send_ipi(mask, type);
}

void smp_timer_broadcast(const struct cpumask *mask)
Expand All @@ -333,7 +242,7 @@ void smp_send_stop(void)
cpumask_copy(&callmap, cpu_online_mask);
cpumask_clear_cpu(smp_processor_id(), &callmap);
if (!cpumask_empty(&callmap))
smp_send_message(callmap, BFIN_IPI_CPU_STOP, NULL, NULL, 0);
send_ipi(&callmap, BFIN_IPI_CPU_STOP);

preempt_enable();

Expand Down Expand Up @@ -436,7 +345,7 @@ void __init smp_prepare_boot_cpu(void)
void __init smp_prepare_cpus(unsigned int max_cpus)
{
platform_prepare_cpus(max_cpus);
ipi_queue_init();
bfin_ipi_init();
platform_request_ipi(IRQ_SUPPLE_0, ipi_handler_int0);
platform_request_ipi(IRQ_SUPPLE_1, ipi_handler_int1);
}
Expand Down

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