1 /* context_sysv - context switching with ucontextes from System V */
3 /* Copyright (c) 2009, 2010. The SimGrid Team.
4 * All rights reserved. */
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. */
11 #include "xbt/parmap.h"
12 #include "smx_private.h"
13 #include "gras_config.h"
14 #include "context_sysv_config.h" /* loads context system definitions */
17 # include <win32_ucontext.h> /* context relative declarations */
19 # include <ucontext.h> /* context relative declarations */
22 #ifdef HAVE_VALGRIND_VALGRIND_H
23 # include <valgrind/valgrind.h>
24 #endif /* HAVE_VALGRIND_VALGRIND_H */
26 XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(simix_context);
28 typedef struct s_smx_ctx_sysv {
29 s_smx_ctx_base_t super; /* Fields of super implementation */
30 ucontext_t uc; /* the ucontext that executes the code */
31 #ifdef HAVE_VALGRIND_VALGRIND_H
32 unsigned int valgrind_stack_id; /* the valgrind stack id */
34 char stack[0]; /* the thread stack (must remain the last element of the structure) */
35 } s_smx_ctx_sysv_t, *smx_ctx_sysv_t;
37 #ifdef CONTEXT_THREADS
38 static xbt_parmap_t sysv_parmap;
39 static ucontext_t* sysv_workers_stacks; /* space to save the worker's stack in each thread */
40 static unsigned long sysv_threads_working; /* number of threads that have started their work */
41 static xbt_os_thread_key_t sysv_worker_id_key; /* thread-specific storage for the thread id */
43 static unsigned long sysv_process_index = 0; /* index of the next process to run in the
44 * list of runnable processes */
45 static smx_ctx_sysv_t sysv_maestro_context;
47 static int smx_ctx_sysv_factory_finalize(smx_context_factory_t *factory);
49 smx_ctx_sysv_create_context_sized(size_t structure_size,
50 xbt_main_func_t code, int argc,
52 void_pfn_smxprocess_t cleanup_func,
54 static void smx_ctx_sysv_free(smx_context_t context);
56 smx_ctx_sysv_create_context(xbt_main_func_t code, int argc, char **argv,
57 void_pfn_smxprocess_t cleanup_func, void* data);
59 static void smx_ctx_sysv_wrapper(int count, ...);
61 static void smx_ctx_sysv_stop_serial(smx_context_t context);
62 static void smx_ctx_sysv_suspend_serial(smx_context_t context);
63 static void smx_ctx_sysv_resume_serial(smx_process_t first_process);
64 static void smx_ctx_sysv_runall_serial(void);
66 static void smx_ctx_sysv_stop_parallel(smx_context_t context);
67 static void smx_ctx_sysv_suspend_parallel(smx_context_t context);
68 static void smx_ctx_sysv_resume_parallel(smx_process_t first_process);
69 static void smx_ctx_sysv_runall_parallel(void);
71 /* This is a bit paranoid about sizeof(smx_ctx_sysv_t) not being a multiple of
72 * sizeof(int), but it doesn't harm. */
73 #define CTX_ADDR_LEN \
74 (sizeof(smx_ctx_sysv_t) / sizeof(int) + \
75 !!(sizeof(smx_ctx_sysv_t) % sizeof(int)))
77 void SIMIX_ctx_sysv_factory_init(smx_context_factory_t *factory)
79 smx_ctx_base_factory_init(factory);
80 XBT_VERB("Activating SYSV context factory");
82 (*factory)->finalize = smx_ctx_sysv_factory_finalize;
83 (*factory)->create_context = smx_ctx_sysv_create_context;
84 /* Do not overload that method (*factory)->finalize */
85 (*factory)->free = smx_ctx_sysv_free;
86 (*factory)->name = "smx_sysv_context_factory";
88 if (SIMIX_context_is_parallel()) {
89 #ifdef CONTEXT_THREADS /* To use parallel ucontexts a thread pool is needed */
90 int nthreads = SIMIX_context_get_nthreads();
91 sysv_parmap = xbt_parmap_new(nthreads, SIMIX_context_get_parallel_mode());
92 sysv_workers_stacks = xbt_new(ucontext_t, nthreads);
93 xbt_os_thread_key_create(&sysv_worker_id_key);
94 (*factory)->stop = smx_ctx_sysv_stop_parallel;
95 (*factory)->suspend = smx_ctx_sysv_suspend_parallel;
96 (*factory)->runall = smx_ctx_sysv_runall_parallel;
98 THROWF(arg_error, 0, "No thread support for parallel context execution");
101 (*factory)->stop = smx_ctx_sysv_stop_serial;
102 (*factory)->suspend = smx_ctx_sysv_suspend_serial;
103 (*factory)->runall = smx_ctx_sysv_runall_serial;
107 static int smx_ctx_sysv_factory_finalize(smx_context_factory_t *factory)
109 #ifdef CONTEXT_THREADS
111 xbt_parmap_destroy(sysv_parmap);
112 xbt_free(sysv_workers_stacks);
114 return smx_ctx_base_factory_finalize(factory);
118 smx_ctx_sysv_create_context_sized(size_t size, xbt_main_func_t code,
119 int argc, char **argv,
120 void_pfn_smxprocess_t cleanup_func,
123 int ctx_addr[CTX_ADDR_LEN];
124 smx_ctx_sysv_t context =
125 (smx_ctx_sysv_t) smx_ctx_base_factory_create_context_sized(size,
132 /* if the user provided a function for the process then use it,
133 otherwise it is the context for maestro */
136 getcontext(&(context->uc));
138 context->uc.uc_link = NULL;
140 context->uc.uc_stack.ss_sp =
141 pth_skaddr_makecontext(context->stack, smx_context_stack_size);
143 context->uc.uc_stack.ss_size =
144 pth_sksize_makecontext(context->stack, smx_context_stack_size);
146 #ifdef HAVE_VALGRIND_VALGRIND_H
147 context->valgrind_stack_id =
148 VALGRIND_STACK_REGISTER(context->uc.uc_stack.ss_sp,
149 ((char *) context->uc.uc_stack.ss_sp) +
150 context->uc.uc_stack.ss_size);
151 #endif /* HAVE_VALGRIND_VALGRIND_H */
152 memcpy(ctx_addr, &context, sizeof(smx_ctx_sysv_t));
153 switch (CTX_ADDR_LEN) {
155 makecontext(&context->uc, (void (*)())smx_ctx_sysv_wrapper,
159 makecontext(&context->uc, (void (*)())smx_ctx_sysv_wrapper,
160 2, ctx_addr[0], ctx_addr[1]);
163 xbt_die("Ucontexts are not supported on this arch yet (addr len = %zu/%zu = %zu)",
164 sizeof(smx_ctx_sysv_t), sizeof(int), CTX_ADDR_LEN);
167 sysv_maestro_context = context;
170 return (smx_context_t) context;
174 smx_ctx_sysv_create_context(xbt_main_func_t code, int argc, char **argv,
175 void_pfn_smxprocess_t cleanup_func,
179 return smx_ctx_sysv_create_context_sized(sizeof(s_smx_ctx_sysv_t) + smx_context_stack_size,
180 code, argc, argv, cleanup_func,
185 static void smx_ctx_sysv_free(smx_context_t context)
190 #ifdef HAVE_VALGRIND_VALGRIND_H
191 VALGRIND_STACK_DEREGISTER(((smx_ctx_sysv_t)
192 context)->valgrind_stack_id);
193 #endif /* HAVE_VALGRIND_VALGRIND_H */
196 smx_ctx_base_free(context);
199 static void smx_ctx_sysv_wrapper(int first, ...)
201 int ctx_addr[CTX_ADDR_LEN];
202 smx_ctx_sysv_t context;
205 if (CTX_ADDR_LEN > 1) {
209 for (i = 1; i < CTX_ADDR_LEN; i++)
210 ctx_addr[i] = va_arg(ap, int);
213 memcpy(&context, ctx_addr, sizeof(smx_ctx_sysv_t));
214 (context->super.code) (context->super.argc, context->super.argv);
216 simix_global->context_factory->stop((smx_context_t) context);
219 static void smx_ctx_sysv_stop_serial(smx_context_t context)
221 smx_ctx_base_stop(context);
222 smx_ctx_sysv_suspend_serial(context);
225 static void smx_ctx_sysv_suspend_serial(smx_context_t context)
227 /* determine the next context */
228 smx_context_t next_context;
229 unsigned long int i = sysv_process_index++;
231 if (i < xbt_dynar_length(simix_global->process_to_run)) {
232 /* execute the next process */
233 XBT_DEBUG("Run next process");
234 next_context = xbt_dynar_get_as(
235 simix_global->process_to_run,i, smx_process_t)->context;
238 /* all processes were run, return to maestro */
239 XBT_DEBUG("No more process to run");
240 next_context = (smx_context_t) sysv_maestro_context;
242 SIMIX_context_set_current(next_context);
243 swapcontext(&((smx_ctx_sysv_t) context)->uc,
244 &((smx_ctx_sysv_t) next_context)->uc);
247 static void smx_ctx_sysv_resume_serial(smx_process_t first_process)
249 smx_context_t context = first_process->context;
250 SIMIX_context_set_current(context);
251 swapcontext(&sysv_maestro_context->uc,
252 &((smx_ctx_sysv_t) context)->uc);
255 static void smx_ctx_sysv_runall_serial(void)
257 if (!xbt_dynar_is_empty(simix_global->process_to_run)) {
258 smx_process_t first_process =
259 xbt_dynar_get_as(simix_global->process_to_run, 0, smx_process_t);
260 sysv_process_index = 1;
262 /* execute the first process */
263 smx_ctx_sysv_resume_serial(first_process);
267 static void smx_ctx_sysv_stop_parallel(smx_context_t context)
269 smx_ctx_base_stop(context);
270 smx_ctx_sysv_suspend_parallel(context);
273 static void smx_ctx_sysv_suspend_parallel(smx_context_t context)
275 #ifdef CONTEXT_THREADS
276 /* determine the next context */
277 smx_process_t next_work = xbt_parmap_next(sysv_parmap);
278 smx_context_t next_context;
279 ucontext_t* next_stack;
281 if (next_work != NULL) {
282 /* there is a next process to resume */
283 XBT_DEBUG("Run next process");
284 next_context = next_work->context;
285 next_stack = &((smx_ctx_sysv_t) next_context)->uc;
288 /* all processes were run, go to the barrier */
289 XBT_DEBUG("No more processes to run");
290 next_context = (smx_context_t) sysv_maestro_context;
291 unsigned long worker_id =
292 (unsigned long) xbt_os_thread_get_specific(sysv_worker_id_key);
293 next_stack = &sysv_workers_stacks[worker_id];
296 SIMIX_context_set_current(next_context);
297 swapcontext(&((smx_ctx_sysv_t) context)->uc, next_stack);
301 static void smx_ctx_sysv_resume_parallel(smx_process_t first_process)
303 #ifdef CONTEXT_THREADS
304 unsigned long worker_id = __sync_fetch_and_add(&sysv_threads_working, 1);
305 xbt_os_thread_set_specific(sysv_worker_id_key, (void*) worker_id);
306 ucontext_t* worker_stack = &sysv_workers_stacks[worker_id];
308 smx_context_t context = first_process->context;
309 SIMIX_context_set_current(context);
310 swapcontext(worker_stack, &((smx_ctx_sysv_t) context)->uc);
314 static void smx_ctx_sysv_runall_parallel(void)
316 #ifdef CONTEXT_THREADS
317 sysv_threads_working = 0;
318 xbt_parmap_apply(sysv_parmap, (void_f_pvoid_t) smx_ctx_sysv_resume_parallel,
319 simix_global->process_to_run);