2 * This program is free software; you can redistribute it and/or
3 * modify it under the terms of the GNU General Public License
4 * as published by the Free Software Foundation; either version 2
5 * of the License, or (at your option) any later version.
7 * This program is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 * GNU General Public License for more details.
12 * You should have received a copy of the GNU General Public License
13 * along with this program; if not, write to the Free Software
14 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
16 * Copyright (C) 2000, 2001 Kanoj Sarcar
17 * Copyright (C) 2000, 2001 Ralf Baechle
18 * Copyright (C) 2000, 2001 Silicon Graphics, Inc.
19 * Copyright (C) 2000, 2001, 2003 Broadcom Corporation
21 #include <linux/cache.h>
22 #include <linux/delay.h>
23 #include <linux/init.h>
24 #include <linux/interrupt.h>
25 #include <linux/spinlock.h>
26 #include <linux/threads.h>
27 #include <linux/module.h>
28 #include <linux/time.h>
29 #include <linux/timex.h>
30 #include <linux/sched.h>
31 #include <linux/cpumask.h>
33 #include <asm/atomic.h>
35 #include <asm/processor.h>
36 #include <asm/system.h>
37 #include <asm/mmu_context.h>
40 cpumask_t phys_cpu_present_map
; /* Bitmask of available CPUs */
41 volatile cpumask_t cpu_callin_map
; /* Bitmask of started secondaries */
42 cpumask_t cpu_online_map
; /* Bitmask of currently online CPUs */
43 int __cpu_number_map
[NR_CPUS
]; /* Map physical to logical */
44 int __cpu_logical_map
[NR_CPUS
]; /* Map logical to physical */
46 EXPORT_SYMBOL(phys_cpu_present_map
);
47 EXPORT_SYMBOL(cpu_online_map
);
49 static void smp_tune_scheduling (void)
51 struct cache_desc
*cd
= ¤t_cpu_data
.scache
;
52 unsigned long cachesize
; /* kB */
53 unsigned long bandwidth
= 350; /* MB/s */
54 unsigned long cpu_khz
;
57 * Crude estimate until we actually meassure ...
59 cpu_khz
= loops_per_jiffy
* 2 * HZ
/ 1000;
62 * Rough estimation for SMP scheduling, this is the number of
63 * cycles it takes for a fully memory-limited process to flush
64 * the SMP-local cache.
66 * (For a P5 this pretty much means we will choose another idle
67 * CPU almost always at wakeup time (this is due to the small
68 * L1 cache), on PIIs it's around 50-100 usecs, depending on
74 cachesize
= cd
->linesz
* cd
->sets
* cd
->ways
;
77 extern void __init
calibrate_delay(void);
78 extern ATTRIB_NORET
void cpu_idle(void);
81 * First C code run on the secondary CPUs after being started up by
84 asmlinkage
void start_secondary(void)
86 unsigned int cpu
= smp_processor_id();
91 prom_init_secondary();
94 * XXX parity protection should be folded in here when it's converted
95 * to an option instead of something based on .cputype
99 cpu_data
[cpu
].udelay_val
= loops_per_jiffy
;
103 cpu_set(cpu
, cpu_callin_map
);
108 DEFINE_SPINLOCK(smp_call_lock
);
110 struct call_data_struct
*call_data
;
113 * Run a function on all other CPUs.
114 * <func> The function to run. This must be fast and non-blocking.
115 * <info> An arbitrary pointer to pass to the function.
116 * <retry> If true, keep retrying until ready.
117 * <wait> If true, wait until function has completed on other CPUs.
118 * [RETURNS] 0 on success, else a negative status code.
120 * Does not return until remote CPUs are nearly ready to execute <func>
121 * or are or have executed.
123 * You must not call this function with disabled interrupts or from a
124 * hardware interrupt handler or from a bottom half handler:
128 * smp_call_function()
131 * Wait for all cpus to acknowledge IPI
132 * CPU A has not responded, spin waiting
133 * for cpu A to respond, holding call_lock
134 * smp_call_function()
135 * Spin waiting for call_lock
138 int smp_call_function (void (*func
) (void *info
), void *info
, int retry
,
141 struct call_data_struct data
;
142 int i
, cpus
= num_online_cpus() - 1;
143 int cpu
= smp_processor_id();
148 /* Can deadlock when called with interrupts disabled */
149 WARN_ON(irqs_disabled());
153 atomic_set(&data
.started
, 0);
156 atomic_set(&data
.finished
, 0);
158 spin_lock(&smp_call_lock
);
162 /* Send a message to all other CPUs and wait for them to respond */
163 for (i
= 0; i
< NR_CPUS
; i
++)
164 if (cpu_online(i
) && i
!= cpu
)
165 core_send_ipi(i
, SMP_CALL_FUNCTION
);
167 /* Wait for response */
168 /* FIXME: lock-up detection, backtrace on lock-up */
169 while (atomic_read(&data
.started
) != cpus
)
173 while (atomic_read(&data
.finished
) != cpus
)
175 spin_unlock(&smp_call_lock
);
180 void smp_call_function_interrupt(void)
182 void (*func
) (void *info
) = call_data
->func
;
183 void *info
= call_data
->info
;
184 int wait
= call_data
->wait
;
187 * Notify initiating CPU that I've grabbed the data and am
188 * about to execute the function.
191 atomic_inc(&call_data
->started
);
194 * At this point the info structure may be out of scope unless wait==1.
202 atomic_inc(&call_data
->finished
);
206 static void stop_this_cpu(void *dummy
)
211 cpu_clear(smp_processor_id(), cpu_online_map
);
212 local_irq_enable(); /* May need to service _machine_restart IPI */
213 for (;;); /* Wait if available. */
216 void smp_send_stop(void)
218 smp_call_function(stop_this_cpu
, NULL
, 1, 0);
221 void __init
smp_cpus_done(unsigned int max_cpus
)
226 /* called from main before smp_init() */
227 void __init
smp_prepare_cpus(unsigned int max_cpus
)
229 init_new_context(current
, &init_mm
);
230 current_thread_info()->cpu
= 0;
231 smp_tune_scheduling();
232 prom_prepare_cpus(max_cpus
);
235 /* preload SMP state for boot cpu */
236 void __devinit
smp_prepare_boot_cpu(void)
239 * This assumes that bootup is always handled by the processor
240 * with the logic and physical number 0.
242 __cpu_number_map
[0] = 0;
243 __cpu_logical_map
[0] = 0;
244 cpu_set(0, phys_cpu_present_map
);
245 cpu_set(0, cpu_online_map
);
246 cpu_set(0, cpu_callin_map
);
250 * Called once for each "cpu_possible(cpu)". Needs to spin up the cpu
251 * and keep control until "cpu_online(cpu)" is set. Note: cpu is
252 * physical, not logical.
254 int __devinit
__cpu_up(unsigned int cpu
)
256 struct task_struct
*idle
;
259 * Processor goes to start_secondary(), sets online flag
260 * The following code is purely to make sure
261 * Linux can schedule processes on this slave.
263 idle
= fork_idle(cpu
);
265 panic(KERN_ERR
"Fork failed for CPU %d", cpu
);
267 prom_boot_secondary(cpu
, idle
);
270 * Trust is futile. We should really have timeouts ...
272 while (!cpu_isset(cpu
, cpu_callin_map
))
275 cpu_set(cpu
, cpu_online_map
);
280 /* Not really SMP stuff ... */
281 int setup_profiling_timer(unsigned int multiplier
)
286 static void flush_tlb_all_ipi(void *info
)
288 local_flush_tlb_all();
291 void flush_tlb_all(void)
293 on_each_cpu(flush_tlb_all_ipi
, 0, 1, 1);
296 static void flush_tlb_mm_ipi(void *mm
)
298 local_flush_tlb_mm((struct mm_struct
*)mm
);
302 * The following tlb flush calls are invoked when old translations are
303 * being torn down, or pte attributes are changing. For single threaded
304 * address spaces, a new context is obtained on the current cpu, and tlb
305 * context on other cpus are invalidated to force a new context allocation
306 * at switch_mm time, should the mm ever be used on other cpus. For
307 * multithreaded address spaces, intercpu interrupts have to be sent.
308 * Another case where intercpu interrupts are required is when the target
309 * mm might be active on another cpu (eg debuggers doing the flushes on
310 * behalf of debugees, kswapd stealing pages from another process etc).
314 void flush_tlb_mm(struct mm_struct
*mm
)
318 if ((atomic_read(&mm
->mm_users
) != 1) || (current
->mm
!= mm
)) {
319 smp_call_function(flush_tlb_mm_ipi
, (void *)mm
, 1, 1);
322 for (i
= 0; i
< num_online_cpus(); i
++)
323 if (smp_processor_id() != i
)
324 cpu_context(i
, mm
) = 0;
326 local_flush_tlb_mm(mm
);
331 struct flush_tlb_data
{
332 struct vm_area_struct
*vma
;
337 static void flush_tlb_range_ipi(void *info
)
339 struct flush_tlb_data
*fd
= (struct flush_tlb_data
*)info
;
341 local_flush_tlb_range(fd
->vma
, fd
->addr1
, fd
->addr2
);
344 void flush_tlb_range(struct vm_area_struct
*vma
, unsigned long start
, unsigned long end
)
346 struct mm_struct
*mm
= vma
->vm_mm
;
349 if ((atomic_read(&mm
->mm_users
) != 1) || (current
->mm
!= mm
)) {
350 struct flush_tlb_data fd
;
355 smp_call_function(flush_tlb_range_ipi
, (void *)&fd
, 1, 1);
358 for (i
= 0; i
< num_online_cpus(); i
++)
359 if (smp_processor_id() != i
)
360 cpu_context(i
, mm
) = 0;
362 local_flush_tlb_range(vma
, start
, end
);
366 static void flush_tlb_kernel_range_ipi(void *info
)
368 struct flush_tlb_data
*fd
= (struct flush_tlb_data
*)info
;
370 local_flush_tlb_kernel_range(fd
->addr1
, fd
->addr2
);
373 void flush_tlb_kernel_range(unsigned long start
, unsigned long end
)
375 struct flush_tlb_data fd
;
379 on_each_cpu(flush_tlb_kernel_range_ipi
, (void *)&fd
, 1, 1);
382 static void flush_tlb_page_ipi(void *info
)
384 struct flush_tlb_data
*fd
= (struct flush_tlb_data
*)info
;
386 local_flush_tlb_page(fd
->vma
, fd
->addr1
);
389 void flush_tlb_page(struct vm_area_struct
*vma
, unsigned long page
)
392 if ((atomic_read(&vma
->vm_mm
->mm_users
) != 1) || (current
->mm
!= vma
->vm_mm
)) {
393 struct flush_tlb_data fd
;
397 smp_call_function(flush_tlb_page_ipi
, (void *)&fd
, 1, 1);
400 for (i
= 0; i
< num_online_cpus(); i
++)
401 if (smp_processor_id() != i
)
402 cpu_context(i
, vma
->vm_mm
) = 0;
404 local_flush_tlb_page(vma
, page
);
408 static void flush_tlb_one_ipi(void *info
)
410 unsigned long vaddr
= (unsigned long) info
;
412 local_flush_tlb_one(vaddr
);
415 void flush_tlb_one(unsigned long vaddr
)
417 smp_call_function(flush_tlb_one_ipi
, (void *) vaddr
, 1, 1);
418 local_flush_tlb_one(vaddr
);
421 EXPORT_SYMBOL(flush_tlb_page
);
422 EXPORT_SYMBOL(flush_tlb_one
);
423 EXPORT_SYMBOL(cpu_data
);
424 EXPORT_SYMBOL(synchronize_irq
);