diff options
Diffstat (limited to 'arch/x86/kernel/smp.c')
-rw-r--r-- | arch/x86/kernel/smp.c | 158 |
1 files changed, 20 insertions, 138 deletions
diff --git a/arch/x86/kernel/smp.c b/arch/x86/kernel/smp.c index 0cb7aadc87cd..361b7a4c640c 100644 --- a/arch/x86/kernel/smp.c +++ b/arch/x86/kernel/smp.c | |||
@@ -121,132 +121,23 @@ static void native_smp_send_reschedule(int cpu) | |||
121 | send_IPI_mask(cpumask_of_cpu(cpu), RESCHEDULE_VECTOR); | 121 | send_IPI_mask(cpumask_of_cpu(cpu), RESCHEDULE_VECTOR); |
122 | } | 122 | } |
123 | 123 | ||
124 | /* | 124 | void native_send_call_func_single_ipi(int cpu) |
125 | * Structure and data for smp_call_function(). This is designed to minimise | ||
126 | * static memory requirements. It also looks cleaner. | ||
127 | */ | ||
128 | static DEFINE_SPINLOCK(call_lock); | ||
129 | |||
130 | struct call_data_struct { | ||
131 | void (*func) (void *info); | ||
132 | void *info; | ||
133 | atomic_t started; | ||
134 | atomic_t finished; | ||
135 | int wait; | ||
136 | }; | ||
137 | |||
138 | void lock_ipi_call_lock(void) | ||
139 | { | 125 | { |
140 | spin_lock_irq(&call_lock); | 126 | send_IPI_mask(cpumask_of_cpu(cpu), CALL_FUNCTION_SINGLE_VECTOR); |
141 | } | ||
142 | |||
143 | void unlock_ipi_call_lock(void) | ||
144 | { | ||
145 | spin_unlock_irq(&call_lock); | ||
146 | } | ||
147 | |||
148 | static struct call_data_struct *call_data; | ||
149 | |||
150 | static void __smp_call_function(void (*func) (void *info), void *info, | ||
151 | int nonatomic, int wait) | ||
152 | { | ||
153 | struct call_data_struct data; | ||
154 | int cpus = num_online_cpus() - 1; | ||
155 | |||
156 | if (!cpus) | ||
157 | return; | ||
158 | |||
159 | data.func = func; | ||
160 | data.info = info; | ||
161 | atomic_set(&data.started, 0); | ||
162 | data.wait = wait; | ||
163 | if (wait) | ||
164 | atomic_set(&data.finished, 0); | ||
165 | |||
166 | call_data = &data; | ||
167 | mb(); | ||
168 | |||
169 | /* Send a message to all other CPUs and wait for them to respond */ | ||
170 | send_IPI_allbutself(CALL_FUNCTION_VECTOR); | ||
171 | |||
172 | /* Wait for response */ | ||
173 | while (atomic_read(&data.started) != cpus) | ||
174 | cpu_relax(); | ||
175 | |||
176 | if (wait) | ||
177 | while (atomic_read(&data.finished) != cpus) | ||
178 | cpu_relax(); | ||
179 | } | 127 | } |
180 | 128 | ||
181 | 129 | void native_send_call_func_ipi(cpumask_t mask) | |
182 | /** | ||
183 | * smp_call_function_mask(): Run a function on a set of other CPUs. | ||
184 | * @mask: The set of cpus to run on. Must not include the current cpu. | ||
185 | * @func: The function to run. This must be fast and non-blocking. | ||
186 | * @info: An arbitrary pointer to pass to the function. | ||
187 | * @wait: If true, wait (atomically) until function has completed on other CPUs. | ||
188 | * | ||
189 | * Returns 0 on success, else a negative status code. | ||
190 | * | ||
191 | * If @wait is true, then returns once @func has returned; otherwise | ||
192 | * it returns just before the target cpu calls @func. | ||
193 | * | ||
194 | * You must not call this function with disabled interrupts or from a | ||
195 | * hardware interrupt handler or from a bottom half handler. | ||
196 | */ | ||
197 | static int | ||
198 | native_smp_call_function_mask(cpumask_t mask, | ||
199 | void (*func)(void *), void *info, | ||
200 | int wait) | ||
201 | { | 130 | { |
202 | struct call_data_struct data; | ||
203 | cpumask_t allbutself; | 131 | cpumask_t allbutself; |
204 | int cpus; | ||
205 | |||
206 | /* Can deadlock when called with interrupts disabled */ | ||
207 | WARN_ON(irqs_disabled()); | ||
208 | |||
209 | /* Holding any lock stops cpus from going down. */ | ||
210 | spin_lock(&call_lock); | ||
211 | 132 | ||
212 | allbutself = cpu_online_map; | 133 | allbutself = cpu_online_map; |
213 | cpu_clear(smp_processor_id(), allbutself); | 134 | cpu_clear(smp_processor_id(), allbutself); |
214 | 135 | ||
215 | cpus_and(mask, mask, allbutself); | ||
216 | cpus = cpus_weight(mask); | ||
217 | |||
218 | if (!cpus) { | ||
219 | spin_unlock(&call_lock); | ||
220 | return 0; | ||
221 | } | ||
222 | |||
223 | data.func = func; | ||
224 | data.info = info; | ||
225 | atomic_set(&data.started, 0); | ||
226 | data.wait = wait; | ||
227 | if (wait) | ||
228 | atomic_set(&data.finished, 0); | ||
229 | |||
230 | call_data = &data; | ||
231 | wmb(); | ||
232 | |||
233 | /* Send a message to other CPUs */ | ||
234 | if (cpus_equal(mask, allbutself) && | 136 | if (cpus_equal(mask, allbutself) && |
235 | cpus_equal(cpu_online_map, cpu_callout_map)) | 137 | cpus_equal(cpu_online_map, cpu_callout_map)) |
236 | send_IPI_allbutself(CALL_FUNCTION_VECTOR); | 138 | send_IPI_allbutself(CALL_FUNCTION_VECTOR); |
237 | else | 139 | else |
238 | send_IPI_mask(mask, CALL_FUNCTION_VECTOR); | 140 | send_IPI_mask(mask, CALL_FUNCTION_VECTOR); |
239 | |||
240 | /* Wait for response */ | ||
241 | while (atomic_read(&data.started) != cpus) | ||
242 | cpu_relax(); | ||
243 | |||
244 | if (wait) | ||
245 | while (atomic_read(&data.finished) != cpus) | ||
246 | cpu_relax(); | ||
247 | spin_unlock(&call_lock); | ||
248 | |||
249 | return 0; | ||
250 | } | 141 | } |
251 | 142 | ||
252 | static void stop_this_cpu(void *dummy) | 143 | static void stop_this_cpu(void *dummy) |
@@ -268,18 +159,13 @@ static void stop_this_cpu(void *dummy) | |||
268 | 159 | ||
269 | static void native_smp_send_stop(void) | 160 | static void native_smp_send_stop(void) |
270 | { | 161 | { |
271 | int nolock; | ||
272 | unsigned long flags; | 162 | unsigned long flags; |
273 | 163 | ||
274 | if (reboot_force) | 164 | if (reboot_force) |
275 | return; | 165 | return; |
276 | 166 | ||
277 | /* Don't deadlock on the call lock in panic */ | 167 | smp_call_function(stop_this_cpu, NULL, 0); |
278 | nolock = !spin_trylock(&call_lock); | ||
279 | local_irq_save(flags); | 168 | local_irq_save(flags); |
280 | __smp_call_function(stop_this_cpu, NULL, 0, 0); | ||
281 | if (!nolock) | ||
282 | spin_unlock(&call_lock); | ||
283 | disable_local_APIC(); | 169 | disable_local_APIC(); |
284 | local_irq_restore(flags); | 170 | local_irq_restore(flags); |
285 | } | 171 | } |
@@ -301,33 +187,28 @@ void smp_reschedule_interrupt(struct pt_regs *regs) | |||
301 | 187 | ||
302 | void smp_call_function_interrupt(struct pt_regs *regs) | 188 | void smp_call_function_interrupt(struct pt_regs *regs) |
303 | { | 189 | { |
304 | void (*func) (void *info) = call_data->func; | ||
305 | void *info = call_data->info; | ||
306 | int wait = call_data->wait; | ||
307 | |||
308 | ack_APIC_irq(); | 190 | ack_APIC_irq(); |
309 | /* | ||
310 | * Notify initiating CPU that I've grabbed the data and am | ||
311 | * about to execute the function | ||
312 | */ | ||
313 | mb(); | ||
314 | atomic_inc(&call_data->started); | ||
315 | /* | ||
316 | * At this point the info structure may be out of scope unless wait==1 | ||
317 | */ | ||
318 | irq_enter(); | 191 | irq_enter(); |
319 | (*func)(info); | 192 | generic_smp_call_function_interrupt(); |
320 | #ifdef CONFIG_X86_32 | 193 | #ifdef CONFIG_X86_32 |
321 | __get_cpu_var(irq_stat).irq_call_count++; | 194 | __get_cpu_var(irq_stat).irq_call_count++; |
322 | #else | 195 | #else |
323 | add_pda(irq_call_count, 1); | 196 | add_pda(irq_call_count, 1); |
324 | #endif | 197 | #endif |
325 | irq_exit(); | 198 | irq_exit(); |
199 | } | ||
326 | 200 | ||
327 | if (wait) { | 201 | void smp_call_function_single_interrupt(struct pt_regs *regs) |
328 | mb(); | 202 | { |
329 | atomic_inc(&call_data->finished); | 203 | ack_APIC_irq(); |
330 | } | 204 | irq_enter(); |
205 | generic_smp_call_function_single_interrupt(); | ||
206 | #ifdef CONFIG_X86_32 | ||
207 | __get_cpu_var(irq_stat).irq_call_count++; | ||
208 | #else | ||
209 | add_pda(irq_call_count, 1); | ||
210 | #endif | ||
211 | irq_exit(); | ||
331 | } | 212 | } |
332 | 213 | ||
333 | struct smp_ops smp_ops = { | 214 | struct smp_ops smp_ops = { |
@@ -338,7 +219,8 @@ struct smp_ops smp_ops = { | |||
338 | 219 | ||
339 | .smp_send_stop = native_smp_send_stop, | 220 | .smp_send_stop = native_smp_send_stop, |
340 | .smp_send_reschedule = native_smp_send_reschedule, | 221 | .smp_send_reschedule = native_smp_send_reschedule, |
341 | .smp_call_function_mask = native_smp_call_function_mask, | 222 | |
223 | .send_call_func_ipi = native_send_call_func_ipi, | ||
224 | .send_call_func_single_ipi = native_send_call_func_single_ipi, | ||
342 | }; | 225 | }; |
343 | EXPORT_SYMBOL_GPL(smp_ops); | 226 | EXPORT_SYMBOL_GPL(smp_ops); |
344 | |||