Implement stride for parmap_apply.

[simgrid.git] / src / simix / smx_context_sysv.c

diff --git a/src/simix/smx_context_sysv.c b/src/simix/smx_context_sysv.c
index 90e6b84..25ef8ec 100644 (file)
--- a/src/simix/smx_context_sysv.c
+++ b/src/simix/smx_context_sysv.c
@@ -1,6 +1,6 @@
-/* context_sysv - context switching with ucontextes from System V           */
+/* context_sysv - context switching with ucontexts from System V           */
 
-/* Copyright (c) 2009, 2010. The SimGrid Team.
+/* Copyright (c) 2009-2013. The SimGrid Team.
  * All rights reserved.                                                     */
 
  /* This program is free software; you can redistribute it and/or modify it
@@ -29,6 +29,7 @@ XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(simix_context);
 typedef struct s_smx_ctx_sysv {
   s_smx_ctx_base_t super;       /* Fields of super implementation */
   ucontext_t uc;                /* the ucontext that executes the code */
+  unsigned int parmap_index;
 #ifdef HAVE_VALGRIND_VALGRIND_H
   unsigned int valgrind_stack_id;       /* the valgrind stack id */
 #endif
@@ -37,7 +38,7 @@ typedef struct s_smx_ctx_sysv {
 
 #ifdef CONTEXT_THREADS
 static xbt_parmap_t sysv_parmap;
-static ucontext_t* sysv_workers_stacks;        /* space to save the worker's stack in each thread */
+static smx_ctx_sysv_t* sysv_workers_context;   /* space to save the worker's context in each thread */
 static unsigned long sysv_threads_working;     /* number of threads that have started their work */
 static xbt_os_thread_key_t sysv_worker_id_key; /* thread-specific storage for the thread id */
 #endif
@@ -90,7 +91,8 @@ void SIMIX_ctx_sysv_factory_init(smx_context_factory_t *factory)
 #ifdef CONTEXT_THREADS  /* To use parallel ucontexts a thread pool is needed */
     int nthreads = SIMIX_context_get_nthreads();
     sysv_parmap = xbt_parmap_new(nthreads, SIMIX_context_get_parallel_mode());
-    sysv_workers_stacks = xbt_new(ucontext_t, nthreads);
+    sysv_workers_context = xbt_new(smx_ctx_sysv_t, nthreads);
+    sysv_maestro_context = NULL;
     xbt_os_thread_key_create(&sysv_worker_id_key);
     (*factory)->stop = smx_ctx_sysv_stop_parallel;
     (*factory)->suspend = smx_ctx_sysv_suspend_parallel;
@@ -110,7 +112,7 @@ static int smx_ctx_sysv_factory_finalize(smx_context_factory_t *factory)
 #ifdef CONTEXT_THREADS
   if (sysv_parmap)
     xbt_parmap_destroy(sysv_parmap);
-  xbt_free(sysv_workers_stacks);
+  xbt_free(sysv_workers_context);
 #endif
   return smx_ctx_base_factory_finalize(factory);
 }
@@ -165,7 +167,8 @@ smx_ctx_sysv_create_context_sized(size_t size, xbt_main_func_t code,
               sizeof(smx_ctx_sysv_t), sizeof(int), CTX_ADDR_LEN);
     }
   } else {
-    sysv_maestro_context = context;
+    if(data != NULL && sysv_maestro_context == NULL)
+      sysv_maestro_context = context;
   }
 
   if(MC_is_active() && code)
@@ -276,23 +279,27 @@ static void smx_ctx_sysv_suspend_parallel(smx_context_t context)
 {
 #ifdef CONTEXT_THREADS
   /* determine the next context */
-  smx_process_t next_work = xbt_parmap_next(sysv_parmap);
+  smx_process_t next_work;
   smx_context_t next_context;
   ucontext_t* next_stack;
 
+  next_work = xbt_parmap_next(sysv_parmap,
+                              &((smx_ctx_sysv_t) context)->parmap_index);
   if (next_work != NULL) {
     /* there is a next process to resume */
     XBT_DEBUG("Run next process");
     next_context = next_work->context;
     next_stack = &((smx_ctx_sysv_t) next_context)->uc;
+    ((smx_ctx_sysv_t) next_context)->parmap_index =
+      ((smx_ctx_sysv_t) context)->parmap_index;
   }
   else {
     /* all processes were run, go to the barrier */
     XBT_DEBUG("No more processes to run");
-    next_context = (smx_context_t) sysv_maestro_context;
     unsigned long worker_id =
         (unsigned long) xbt_os_thread_get_specific(sysv_worker_id_key);
-    next_stack = &sysv_workers_stacks[worker_id];
+    next_context = (smx_context_t)sysv_workers_context[worker_id];
+    next_stack = &((smx_ctx_sysv_t)next_context)->uc;
   }
 
   SIMIX_context_set_current(next_context);
@@ -305,11 +312,18 @@ static void smx_ctx_sysv_resume_parallel(smx_process_t first_process)
 #ifdef CONTEXT_THREADS
   unsigned long worker_id = __sync_fetch_and_add(&sysv_threads_working, 1);
   xbt_os_thread_set_specific(sysv_worker_id_key, (void*) worker_id);
-  ucontext_t* worker_stack = &sysv_workers_stacks[worker_id];
-
-  smx_context_t context = first_process->context;
-  SIMIX_context_set_current(context);
-  swapcontext(worker_stack, &((smx_ctx_sysv_t) context)->uc);
+  smx_ctx_sysv_t worker_context = (smx_ctx_sysv_t)SIMIX_context_self();
+  sysv_workers_context[worker_id] = worker_context;
+  ucontext_t* worker_stack = &worker_context->uc;
+  unsigned int index = 0;
+
+  first_process = xbt_parmap_next(sysv_parmap, &index);
+  if (first_process != NULL) {
+    smx_context_t context = first_process->context;
+    ((smx_ctx_sysv_t) context)->parmap_index = index;
+    SIMIX_context_set_current(context);
+    swapcontext(worker_stack, &((smx_ctx_sysv_t) context)->uc);
+  }
 #endif
 }
 
@@ -318,6 +332,7 @@ static void smx_ctx_sysv_runall_parallel(void)
 #ifdef CONTEXT_THREADS
   sysv_threads_working = 0;
   xbt_parmap_apply(sysv_parmap, (void_f_pvoid_t) smx_ctx_sysv_resume_parallel,
-      simix_global->process_to_run);
+                   simix_global->process_to_run,
+                   1 + SIMIX_context_get_parallel_threshold() / SIMIX_context_get_nthreads(), 1);
 #endif
 }