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authorJens Axboe <jens.axboe@oracle.com>2008-06-26 05:22:30 -0400
committerJens Axboe <jens.axboe@oracle.com>2008-06-26 05:22:30 -0400
commitf27b433ef32a77c8cb76f018507453df7c03e552 (patch)
tree928f03e2325a9b7f1d9543603bfd1a7133b2fdfa /arch/ia64/kernel/smp.c
parentb7d7a2404f80386307ccc0cde63d8d2a5e3bc85c (diff)
ia64: convert to generic helpers for IPI function calls
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>
Diffstat (limited to 'arch/ia64/kernel/smp.c')
-rw-r--r--arch/ia64/kernel/smp.c250
1 files changed, 13 insertions, 237 deletions
diff --git a/arch/ia64/kernel/smp.c b/arch/ia64/kernel/smp.c
index 983296f1c813..19152dcbf6e4 100644
--- a/arch/ia64/kernel/smp.c
+++ b/arch/ia64/kernel/smp.c
@@ -60,25 +60,9 @@ static struct local_tlb_flush_counts {
60 60
61static DEFINE_PER_CPU(unsigned int, shadow_flush_counts[NR_CPUS]) ____cacheline_aligned; 61static DEFINE_PER_CPU(unsigned int, shadow_flush_counts[NR_CPUS]) ____cacheline_aligned;
62 62
63
64/*
65 * Structure and data for smp_call_function(). This is designed to minimise static memory
66 * requirements. It also looks cleaner.
67 */
68static __cacheline_aligned DEFINE_SPINLOCK(call_lock);
69
70struct call_data_struct {
71 void (*func) (void *info);
72 void *info;
73 long wait;
74 atomic_t started;
75 atomic_t finished;
76};
77
78static volatile struct call_data_struct *call_data;
79
80#define IPI_CALL_FUNC 0 63#define IPI_CALL_FUNC 0
81#define IPI_CPU_STOP 1 64#define IPI_CPU_STOP 1
65#define IPI_CALL_FUNC_SINGLE 2
82#define IPI_KDUMP_CPU_STOP 3 66#define IPI_KDUMP_CPU_STOP 3
83 67
84/* This needs to be cacheline aligned because it is written to by *other* CPUs. */ 68/* This needs to be cacheline aligned because it is written to by *other* CPUs. */
@@ -86,43 +70,6 @@ static DEFINE_PER_CPU_SHARED_ALIGNED(u64, ipi_operation);
86 70
87extern void cpu_halt (void); 71extern void cpu_halt (void);
88 72
89void
90lock_ipi_calllock(void)
91{
92 spin_lock_irq(&call_lock);
93}
94
95void
96unlock_ipi_calllock(void)
97{
98 spin_unlock_irq(&call_lock);
99}
100
101static inline void
102handle_call_data(void)
103{
104 struct call_data_struct *data;
105 void (*func)(void *info);
106 void *info;
107 int wait;
108
109 /* release the 'pointer lock' */
110 data = (struct call_data_struct *)call_data;
111 func = data->func;
112 info = data->info;
113 wait = data->wait;
114
115 mb();
116 atomic_inc(&data->started);
117 /* At this point the structure may be gone unless wait is true. */
118 (*func)(info);
119
120 /* Notify the sending CPU that the task is done. */
121 mb();
122 if (wait)
123 atomic_inc(&data->finished);
124}
125
126static void 73static void
127stop_this_cpu(void) 74stop_this_cpu(void)
128{ 75{
@@ -163,13 +110,15 @@ handle_IPI (int irq, void *dev_id)
163 ops &= ~(1 << which); 110 ops &= ~(1 << which);
164 111
165 switch (which) { 112 switch (which) {
166 case IPI_CALL_FUNC:
167 handle_call_data();
168 break;
169
170 case IPI_CPU_STOP: 113 case IPI_CPU_STOP:
171 stop_this_cpu(); 114 stop_this_cpu();
172 break; 115 break;
116 case IPI_CALL_FUNC:
117 generic_smp_call_function_interrupt();
118 break;
119 case IPI_CALL_FUNC_SINGLE:
120 generic_smp_call_function_single_interrupt();
121 break;
173#ifdef CONFIG_KEXEC 122#ifdef CONFIG_KEXEC
174 case IPI_KDUMP_CPU_STOP: 123 case IPI_KDUMP_CPU_STOP:
175 unw_init_running(kdump_cpu_freeze, NULL); 124 unw_init_running(kdump_cpu_freeze, NULL);
@@ -187,6 +136,8 @@ handle_IPI (int irq, void *dev_id)
187 return IRQ_HANDLED; 136 return IRQ_HANDLED;
188} 137}
189 138
139
140
190/* 141/*
191 * Called with preemption disabled. 142 * Called with preemption disabled.
192 */ 143 */
@@ -360,190 +311,15 @@ smp_flush_tlb_mm (struct mm_struct *mm)
360 on_each_cpu((void (*)(void *))local_finish_flush_tlb_mm, mm, 1, 1); 311 on_each_cpu((void (*)(void *))local_finish_flush_tlb_mm, mm, 1, 1);
361} 312}
362 313
363/* 314void arch_send_call_function_single_ipi(int cpu)
364 * Run a function on a specific CPU
365 * <func> The function to run. This must be fast and non-blocking.
366 * <info> An arbitrary pointer to pass to the function.
367 * <nonatomic> Currently unused.
368 * <wait> If true, wait until function has completed on other CPUs.
369 * [RETURNS] 0 on success, else a negative status code.
370 *
371 * Does not return until the remote CPU is nearly ready to execute <func>
372 * or is or has executed.
373 */
374
375int
376smp_call_function_single (int cpuid, void (*func) (void *info), void *info, int nonatomic,
377 int wait)
378{
379 struct call_data_struct data;
380 int cpus = 1;
381 int me = get_cpu(); /* prevent preemption and reschedule on another processor */
382
383 if (cpuid == me) {
384 local_irq_disable();
385 func(info);
386 local_irq_enable();
387 put_cpu();
388 return 0;
389 }
390
391 data.func = func;
392 data.info = info;
393 atomic_set(&data.started, 0);
394 data.wait = wait;
395 if (wait)
396 atomic_set(&data.finished, 0);
397
398 spin_lock_bh(&call_lock);
399
400 call_data = &data;
401 mb(); /* ensure store to call_data precedes setting of IPI_CALL_FUNC */
402 send_IPI_single(cpuid, IPI_CALL_FUNC);
403
404 /* Wait for response */
405 while (atomic_read(&data.started) != cpus)
406 cpu_relax();
407
408 if (wait)
409 while (atomic_read(&data.finished) != cpus)
410 cpu_relax();
411 call_data = NULL;
412
413 spin_unlock_bh(&call_lock);
414 put_cpu();
415 return 0;
416}
417EXPORT_SYMBOL(smp_call_function_single);
418
419/**
420 * smp_call_function_mask(): Run a function on a set of other CPUs.
421 * <mask> The set of cpus to run on. Must not include the current cpu.
422 * <func> The function to run. This must be fast and non-blocking.
423 * <info> An arbitrary pointer to pass to the function.
424 * <wait> If true, wait (atomically) until function
425 * has completed on other CPUs.
426 *
427 * Returns 0 on success, else a negative status code.
428 *
429 * If @wait is true, then returns once @func has returned; otherwise
430 * it returns just before the target cpu calls @func.
431 *
432 * You must not call this function with disabled interrupts or from a
433 * hardware interrupt handler or from a bottom half handler.
434 */
435int smp_call_function_mask(cpumask_t mask,
436 void (*func)(void *), void *info,
437 int wait)
438{ 315{
439 struct call_data_struct data; 316 send_IPI_single(cpu, IPI_CALL_FUNC_SINGLE);
440 cpumask_t allbutself;
441 int cpus;
442
443 spin_lock(&call_lock);
444 allbutself = cpu_online_map;
445 cpu_clear(smp_processor_id(), allbutself);
446
447 cpus_and(mask, mask, allbutself);
448 cpus = cpus_weight(mask);
449 if (!cpus) {
450 spin_unlock(&call_lock);
451 return 0;
452 }
453
454 /* Can deadlock when called with interrupts disabled */
455 WARN_ON(irqs_disabled());
456
457 data.func = func;
458 data.info = info;
459 atomic_set(&data.started, 0);
460 data.wait = wait;
461 if (wait)
462 atomic_set(&data.finished, 0);
463
464 call_data = &data;
465 mb(); /* ensure store to call_data precedes setting of IPI_CALL_FUNC*/
466
467 /* Send a message to other CPUs */
468 if (cpus_equal(mask, allbutself))
469 send_IPI_allbutself(IPI_CALL_FUNC);
470 else
471 send_IPI_mask(mask, IPI_CALL_FUNC);
472
473 /* Wait for response */
474 while (atomic_read(&data.started) != cpus)
475 cpu_relax();
476
477 if (wait)
478 while (atomic_read(&data.finished) != cpus)
479 cpu_relax();
480 call_data = NULL;
481
482 spin_unlock(&call_lock);
483 return 0;
484
485} 317}
486EXPORT_SYMBOL(smp_call_function_mask);
487 318
488/* 319void arch_send_call_function_ipi(cpumask_t mask)
489 * this function sends a 'generic call function' IPI to all other CPUs
490 * in the system.
491 */
492
493/*
494 * [SUMMARY] Run a function on all other CPUs.
495 * <func> The function to run. This must be fast and non-blocking.
496 * <info> An arbitrary pointer to pass to the function.
497 * <nonatomic> currently unused.
498 * <wait> If true, wait (atomically) until function has completed on other CPUs.
499 * [RETURNS] 0 on success, else a negative status code.
500 *
501 * Does not return until remote CPUs are nearly ready to execute <func> or are or have
502 * executed.
503 *
504 * You must not call this function with disabled interrupts or from a
505 * hardware interrupt handler or from a bottom half handler.
506 */
507int
508smp_call_function (void (*func) (void *info), void *info, int nonatomic, int wait)
509{ 320{
510 struct call_data_struct data; 321 send_IPI_mask(mask, IPI_CALL_FUNC);
511 int cpus;
512
513 spin_lock(&call_lock);
514 cpus = num_online_cpus() - 1;
515 if (!cpus) {
516 spin_unlock(&call_lock);
517 return 0;
518 }
519
520 /* Can deadlock when called with interrupts disabled */
521 WARN_ON(irqs_disabled());
522
523 data.func = func;
524 data.info = info;
525 atomic_set(&data.started, 0);
526 data.wait = wait;
527 if (wait)
528 atomic_set(&data.finished, 0);
529
530 call_data = &data;
531 mb(); /* ensure store to call_data precedes setting of IPI_CALL_FUNC */
532 send_IPI_allbutself(IPI_CALL_FUNC);
533
534 /* Wait for response */
535 while (atomic_read(&data.started) != cpus)
536 cpu_relax();
537
538 if (wait)
539 while (atomic_read(&data.finished) != cpus)
540 cpu_relax();
541 call_data = NULL;
542
543 spin_unlock(&call_lock);
544 return 0;
545} 322}
546EXPORT_SYMBOL(smp_call_function);
547 323
548/* 324/*
549 * this function calls the 'stop' function on all other CPUs in the system. 325 * this function calls the 'stop' function on all other CPUs in the system.