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Factorize stack creation.
[simgrid.git] / src / simix / smx_context_sysv.c
1 /* context_sysv - context switching with ucontexts from System V           */
2
3 /* Copyright (c) 2009-2014. The SimGrid Team.
4  * All rights reserved.                                                     */
5
6 /* This program is free software; you can redistribute it and/or modify it
7  * under the terms of the license (GNU LGPL) which comes with this package. */
8
9 #include <stdarg.h>
10
11 #include "xbt/parmap.h"
12 #include "smx_private.h"
13 #include "internal_config.h"
14 #include "context_sysv_config.h"        /* loads context system definitions */
15 #include "mc/mc.h"
16
17 #ifdef _XBT_WIN32
18 #  include <win32_ucontext.h>     /* context relative declarations */
19 #else
20 #  include <ucontext.h>           /* context relative declarations */
21 #endif
22
23 #ifdef HAVE_VALGRIND_VALGRIND_H
24 #  include <valgrind/valgrind.h>
25 #endif                          /* HAVE_VALGRIND_VALGRIND_H */
26
27 XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(simix_context);
28
29 typedef struct s_smx_ctx_sysv {
30   s_smx_ctx_base_t super;       /* Fields of super implementation */
31   ucontext_t uc;                /* the ucontext that executes the code */
32 #ifdef HAVE_VALGRIND_VALGRIND_H
33   unsigned int valgrind_stack_id;       /* the valgrind stack id */
34 #endif
35   char *stack;                  /* the thread stack */
36 } s_smx_ctx_sysv_t, *smx_ctx_sysv_t;
37
38 #ifdef CONTEXT_THREADS
39 static xbt_parmap_t sysv_parmap;
40 static smx_ctx_sysv_t* sysv_workers_context;   /* space to save the worker's context in each thread */
41 static unsigned long sysv_threads_working;     /* number of threads that have started their work */
42 static xbt_os_thread_key_t sysv_worker_id_key; /* thread-specific storage for the thread id */
43 #endif
44 static unsigned long sysv_process_index = 0;   /* index of the next process to run in the
45                                                 * list of runnable processes */
46 static smx_ctx_sysv_t sysv_maestro_context;
47
48 static int smx_ctx_sysv_factory_finalize(smx_context_factory_t *factory);
49 static smx_context_t
50 smx_ctx_sysv_create_context_sized(size_t structure_size,
51                                   xbt_main_func_t code, int argc,
52                                   char **argv,
53                                   void_pfn_smxprocess_t cleanup_func,
54                                   smx_process_t process);
55 static void smx_ctx_sysv_free(smx_context_t context);
56 static smx_context_t
57 smx_ctx_sysv_create_context(xbt_main_func_t code, int argc, char **argv,
58     void_pfn_smxprocess_t cleanup_func, smx_process_t process);
59
60 static void smx_ctx_sysv_wrapper(int count, ...);
61
62 static void smx_ctx_sysv_stop_serial(smx_context_t context);
63 static void smx_ctx_sysv_suspend_serial(smx_context_t context);
64 static void smx_ctx_sysv_resume_serial(smx_process_t first_process);
65 static void smx_ctx_sysv_runall_serial(void);
66
67 static void smx_ctx_sysv_stop_parallel(smx_context_t context);
68 static void smx_ctx_sysv_suspend_parallel(smx_context_t context);
69 static void smx_ctx_sysv_resume_parallel(smx_process_t first_process);
70 static void smx_ctx_sysv_runall_parallel(void);
71
72 /* This is a bit paranoid about sizeof(smx_ctx_sysv_t) not being a multiple of
73  * sizeof(int), but it doesn't harm. */
74 #define CTX_ADDR_LEN                            \
75   (sizeof(smx_ctx_sysv_t) / sizeof(int) +       \
76    !!(sizeof(smx_ctx_sysv_t) % sizeof(int)))
77
78 void SIMIX_ctx_sysv_factory_init(smx_context_factory_t *factory)
79 {
80   smx_ctx_base_factory_init(factory);
81   XBT_VERB("Activating SYSV context factory");
82
83   (*factory)->finalize = smx_ctx_sysv_factory_finalize;
84   (*factory)->create_context = smx_ctx_sysv_create_context;
85   /* Do not overload that method (*factory)->finalize */
86   (*factory)->free = smx_ctx_sysv_free;
87   (*factory)->name = "smx_sysv_context_factory";
88
89   if (SIMIX_context_is_parallel()) {
90 #ifdef CONTEXT_THREADS  /* To use parallel ucontexts a thread pool is needed */
91     int nthreads = SIMIX_context_get_nthreads();
92     sysv_parmap = xbt_parmap_new(nthreads, SIMIX_context_get_parallel_mode());
93     sysv_workers_context = xbt_new(smx_ctx_sysv_t, nthreads);
94     sysv_maestro_context = NULL;
95     xbt_os_thread_key_create(&sysv_worker_id_key);
96     (*factory)->stop = smx_ctx_sysv_stop_parallel;
97     (*factory)->suspend = smx_ctx_sysv_suspend_parallel;
98     (*factory)->runall = smx_ctx_sysv_runall_parallel;
99 #else
100     THROWF(arg_error, 0, "No thread support for parallel context execution");
101 #endif
102   } else {
103     (*factory)->stop = smx_ctx_sysv_stop_serial;
104     (*factory)->suspend = smx_ctx_sysv_suspend_serial;
105     (*factory)->runall = smx_ctx_sysv_runall_serial;
106   }    
107 }
108
109 static int smx_ctx_sysv_factory_finalize(smx_context_factory_t *factory)
110
111 #ifdef CONTEXT_THREADS
112   if (sysv_parmap)
113     xbt_parmap_destroy(sysv_parmap);
114   xbt_free(sysv_workers_context);
115 #endif
116   return smx_ctx_base_factory_finalize(factory);
117 }
118
119 static smx_context_t
120 smx_ctx_sysv_create_context_sized(size_t size, xbt_main_func_t code,
121                                   int argc, char **argv,
122                                   void_pfn_smxprocess_t cleanup_func,
123                                   smx_process_t process)
124 {
125   int ctx_addr[CTX_ADDR_LEN];
126   smx_ctx_sysv_t context =
127       (smx_ctx_sysv_t) smx_ctx_base_factory_create_context_sized(size,
128                                                                  code,
129                                                                  argc,
130                                                                  argv,
131                                                                  cleanup_func,
132                                                                  process);
133
134   /* if the user provided a function for the process then use it,
135      otherwise it is the context for maestro */
136   if (code) {
137
138     context->stack = SIMIX_context_stack_new();
139     getcontext(&(context->uc));
140
141     context->uc.uc_link = NULL;
142
143     context->uc.uc_stack.ss_sp =
144         pth_skaddr_makecontext(context->stack, smx_context_stack_size);
145
146     context->uc.uc_stack.ss_size =
147         pth_sksize_makecontext(context->stack, smx_context_stack_size);
148
149 #ifdef HAVE_VALGRIND_VALGRIND_H
150     context->valgrind_stack_id =
151         VALGRIND_STACK_REGISTER(context->uc.uc_stack.ss_sp,
152                                 ((char *) context->uc.uc_stack.ss_sp) +
153                                 context->uc.uc_stack.ss_size);
154 #endif                          /* HAVE_VALGRIND_VALGRIND_H */
155     memcpy(ctx_addr, &context, sizeof(smx_ctx_sysv_t));
156     switch (CTX_ADDR_LEN) {
157     case 1:
158       makecontext(&context->uc, (void (*)())smx_ctx_sysv_wrapper,
159                   1, ctx_addr[0]);
160       break;
161     case 2:
162       makecontext(&context->uc, (void (*)())smx_ctx_sysv_wrapper,
163                   2, ctx_addr[0], ctx_addr[1]);
164       break;
165     default:
166       xbt_die("Ucontexts are not supported on this arch yet (addr len = %zu/%zu = %zu)",
167               sizeof(smx_ctx_sysv_t), sizeof(int), CTX_ADDR_LEN);
168     }
169   } else {
170     if (process != NULL && sysv_maestro_context == NULL)
171       sysv_maestro_context = context;
172   }
173
174   if(MC_is_active() && code)
175     MC_new_stack_area(context, ((smx_context_t)context)->process->name,
176                       &(context->uc), size);
177
178   return (smx_context_t) context;
179 }
180
181 static smx_context_t
182 smx_ctx_sysv_create_context(xbt_main_func_t code, int argc, char **argv,
183                             void_pfn_smxprocess_t cleanup_func,
184                             smx_process_t process)
185 {
186
187   return smx_ctx_sysv_create_context_sized(sizeof(s_smx_ctx_sysv_t),
188                                            code, argc, argv, cleanup_func,
189                                            process);
190
191 }
192
193 static void smx_ctx_sysv_free(smx_context_t context)
194 {
195
196   if (context) {
197
198 #ifdef HAVE_VALGRIND_VALGRIND_H
199     VALGRIND_STACK_DEREGISTER(((smx_ctx_sysv_t)
200                                context)->valgrind_stack_id);
201 #endif                          /* HAVE_VALGRIND_VALGRIND_H */
202     SIMIX_context_stack_delete(((smx_ctx_sysv_t)context)->stack);
203   }
204   smx_ctx_base_free(context);
205 }
206
207 static void smx_ctx_sysv_wrapper(int first, ...)
208
209   int ctx_addr[CTX_ADDR_LEN];
210   smx_ctx_sysv_t context;
211
212   ctx_addr[0] = first;
213   if (CTX_ADDR_LEN > 1) {
214     va_list ap;
215     int i;
216     va_start(ap, first);
217     for (i = 1; i < CTX_ADDR_LEN; i++)
218       ctx_addr[i] = va_arg(ap, int);
219     va_end(ap);
220   }
221   memcpy(&context, ctx_addr, sizeof(smx_ctx_sysv_t));
222   (context->super.code) (context->super.argc, context->super.argv);
223
224   simix_global->context_factory->stop((smx_context_t) context);
225 }
226
227 static void smx_ctx_sysv_stop_serial(smx_context_t context)
228 {
229   smx_ctx_base_stop(context);
230   smx_ctx_sysv_suspend_serial(context);
231 }
232
233 static void smx_ctx_sysv_suspend_serial(smx_context_t context)
234 {
235   /* determine the next context */
236   smx_context_t next_context;
237   unsigned long int i = sysv_process_index++;
238
239   if (i < xbt_dynar_length(simix_global->process_to_run)) {
240     /* execute the next process */
241     XBT_DEBUG("Run next process");
242     next_context = xbt_dynar_get_as(
243         simix_global->process_to_run,i, smx_process_t)->context;
244   }
245   else {
246     /* all processes were run, return to maestro */
247     XBT_DEBUG("No more process to run");
248     next_context = (smx_context_t) sysv_maestro_context;
249   }
250   SIMIX_context_set_current(next_context);
251   swapcontext(&((smx_ctx_sysv_t) context)->uc,
252       &((smx_ctx_sysv_t) next_context)->uc);
253 }
254
255 static void smx_ctx_sysv_resume_serial(smx_process_t first_process)
256 {
257   smx_context_t context = first_process->context;
258   SIMIX_context_set_current(context);
259   swapcontext(&sysv_maestro_context->uc,
260       &((smx_ctx_sysv_t) context)->uc);
261 }
262
263 static void smx_ctx_sysv_runall_serial(void)
264 {
265   smx_process_t first_process =
266       xbt_dynar_get_as(simix_global->process_to_run, 0, smx_process_t);
267   sysv_process_index = 1;
268
269   /* execute the first process */
270   smx_ctx_sysv_resume_serial(first_process);
271 }
272
273 static void smx_ctx_sysv_stop_parallel(smx_context_t context)
274 {
275   smx_ctx_base_stop(context);
276   smx_ctx_sysv_suspend_parallel(context);
277 }
278
279 static void smx_ctx_sysv_suspend_parallel(smx_context_t context)
280 {
281 #ifdef CONTEXT_THREADS
282   /* determine the next context */
283   smx_process_t next_work = xbt_parmap_next(sysv_parmap);
284   smx_context_t next_context;
285   ucontext_t* next_stack;
286
287   if (next_work != NULL) {
288     /* there is a next process to resume */
289     XBT_DEBUG("Run next process");
290     next_context = next_work->context;
291     next_stack = &((smx_ctx_sysv_t) next_context)->uc;
292   }
293   else {
294     /* all processes were run, go to the barrier */
295     XBT_DEBUG("No more processes to run");
296     unsigned long worker_id =
297         (unsigned long) xbt_os_thread_get_specific(sysv_worker_id_key);
298     next_context = (smx_context_t)sysv_workers_context[worker_id];
299     next_stack = &((smx_ctx_sysv_t)next_context)->uc;
300   }
301
302   SIMIX_context_set_current(next_context);
303   swapcontext(&((smx_ctx_sysv_t) context)->uc, next_stack);
304 #endif
305 }
306
307 static void smx_ctx_sysv_resume_parallel(smx_process_t first_process)
308 {
309 #ifdef CONTEXT_THREADS
310   unsigned long worker_id = __sync_fetch_and_add(&sysv_threads_working, 1);
311   xbt_os_thread_set_specific(sysv_worker_id_key, (void*) worker_id);
312   smx_ctx_sysv_t worker_context = (smx_ctx_sysv_t)SIMIX_context_self();
313   sysv_workers_context[worker_id] = worker_context;
314   ucontext_t* worker_stack = &worker_context->uc;
315
316   smx_context_t context = first_process->context;
317   SIMIX_context_set_current(context);
318   swapcontext(worker_stack, &((smx_ctx_sysv_t) context)->uc);
319 #endif
320 }
321
322 static void smx_ctx_sysv_runall_parallel(void)
323 {
324 #ifdef CONTEXT_THREADS
325   sysv_threads_working = 0;
326   xbt_parmap_apply(sysv_parmap, (void_f_pvoid_t) smx_ctx_sysv_resume_parallel,
327       simix_global->process_to_run);
328 #endif
329 }