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Also remove forward declaration for removed function.
[simgrid.git] / src / simix / smx_context_sysv.c
index 9458a3b..9db467f 100644 (file)
-/* 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) 2009-2014. The SimGrid Team.
  * All rights reserved.                                                     */
 
- /* This program is free software; you can redistribute it and/or modify it
 * under the terms of the license (GNU LGPL) which comes with this package. */
+/* This program is free software; you can redistribute it and/or modify it
+ * under the terms of the license (GNU LGPL) which comes with this package. */
 
+#include <stdarg.h>
 
+#include "xbt/parmap.h"
+#include "smx_private.h"
+#include "internal_config.h"
+#include "context_sysv_config.h"        /* loads context system definitions */
+#include "mc/mc.h"
 
-#include "smx_context_sysv_private.h"
-#include "xbt/threadpool.h"
+#ifdef _XBT_WIN32
+#  include <win32_ucontext.h>     /* context relative declarations */
+#else
+#  include <ucontext.h>           /* context relative declarations */
+#endif
 
 #ifdef HAVE_VALGRIND_VALGRIND_H
 #  include <valgrind/valgrind.h>
 #endif                          /* HAVE_VALGRIND_VALGRIND_H */
 
-#ifdef _XBT_WIN32
-#include "win32_ucontext.h"
-#include "win32_ucontext.c"
-#else
-#include "ucontext.h"
-#endif
-
 XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(simix_context);
 
-static xbt_tpool_t tpool; 
+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 */
+#ifdef HAVE_VALGRIND_VALGRIND_H
+  unsigned int valgrind_stack_id;       /* the valgrind stack id */
+#endif
+  char *stack;                  /* the thread stack */
+} s_smx_ctx_sysv_t, *smx_ctx_sysv_t;
+
+#ifdef CONTEXT_THREADS
+static xbt_parmap_t sysv_parmap;
+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
+static unsigned long sysv_process_index = 0;   /* index of the next process to run in the
+                                                * list of runnable processes */
+static smx_ctx_sysv_t sysv_maestro_context;
 
+static int smx_ctx_sysv_factory_finalize(smx_context_factory_t *factory);
+static void smx_ctx_sysv_free(smx_context_t context);
 static smx_context_t
 smx_ctx_sysv_create_context(xbt_main_func_t code, int argc, char **argv,
-    void_pfn_smxprocess_t cleanup_func, void* data);
+    void_pfn_smxprocess_t cleanup_func, smx_process_t process);
+
+static void smx_ctx_sysv_wrapper(int count, ...);
 
+static void smx_ctx_sysv_stop_serial(smx_context_t context);
+static void smx_ctx_sysv_suspend_serial(smx_context_t context);
+static void smx_ctx_sysv_resume_serial(smx_process_t first_process);
+static void smx_ctx_sysv_runall_serial(void);
 
-static void smx_ctx_sysv_wrapper(smx_ctx_sysv_t context);
+static void smx_ctx_sysv_stop_parallel(smx_context_t context);
+static void smx_ctx_sysv_suspend_parallel(smx_context_t context);
+static void smx_ctx_sysv_resume_parallel(smx_process_t first_process);
+static void smx_ctx_sysv_runall_parallel(void);
 
-void SIMIX_ctx_sysv_factory_init(smx_context_factory_t * factory)
+/* This is a bit paranoid about sizeof(smx_ctx_sysv_t) not being a multiple of
+ * sizeof(int), but it doesn't harm. */
+#define CTX_ADDR_LEN                            \
+  (sizeof(smx_ctx_sysv_t) / sizeof(int) +       \
+   !!(sizeof(smx_ctx_sysv_t) % sizeof(int)))
+
+void SIMIX_ctx_sysv_factory_init(smx_context_factory_t *factory)
 {
   smx_ctx_base_factory_init(factory);
+  XBT_VERB("Activating SYSV context factory");
 
   (*factory)->finalize = smx_ctx_sysv_factory_finalize;
   (*factory)->create_context = smx_ctx_sysv_create_context;
   /* Do not overload that method (*factory)->finalize */
   (*factory)->free = smx_ctx_sysv_free;
-  (*factory)->stop = smx_ctx_sysv_stop;
-  (*factory)->suspend = smx_ctx_sysv_suspend;
   (*factory)->name = "smx_sysv_context_factory";
 
-  if(_surf_parallel_contexts){
-    tpool = xbt_tpool_new(2, 10);
+  if (SIMIX_context_is_parallel()) {
+#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_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;
     (*factory)->runall = smx_ctx_sysv_runall_parallel;
-  }else{
-    (*factory)->runall = smx_ctx_sysv_runall;
+#else
+    THROWF(arg_error, 0, "No thread support for parallel context execution");
+#endif
+  } else {
+    (*factory)->stop = smx_ctx_sysv_stop_serial;
+    (*factory)->suspend = smx_ctx_sysv_suspend_serial;
+    (*factory)->runall = smx_ctx_sysv_runall_serial;
   }    
 }
 
-int smx_ctx_sysv_factory_finalize(smx_context_factory_t *factory)
+static int smx_ctx_sysv_factory_finalize(smx_context_factory_t *factory)
 { 
-  if(tpool)
-    xbt_tpool_destroy(tpool);
+#ifdef CONTEXT_THREADS
+  if (sysv_parmap)
+    xbt_parmap_destroy(sysv_parmap);
+  xbt_free(sysv_workers_context);
+#endif
   return smx_ctx_base_factory_finalize(factory);
 }
 
-smx_context_t
-smx_ctx_sysv_create_context_sized(size_t size, xbt_main_func_t code,
-                                  int argc, char **argv,
-                                  void_pfn_smxprocess_t cleanup_func,
-                                  void *data)
+static smx_context_t
+smx_ctx_sysv_create_context(xbt_main_func_t code, int argc, char **argv,
+                            void_pfn_smxprocess_t cleanup_func,
+                            smx_process_t process)
 {
-
+  int ctx_addr[CTX_ADDR_LEN];
   smx_ctx_sysv_t context =
-      (smx_ctx_sysv_t) smx_ctx_base_factory_create_context_sized(size,
-                                                                 code,
-                                                                 argc,
-                                                                 argv,
-                                                                 cleanup_func,
-                                                                 data);
-
-  /* If the user provided a function for the process then use it
-     otherwise is the context for maestro */
+    (smx_ctx_sysv_t) smx_ctx_base_factory_create_context_sized(
+      sizeof(s_smx_ctx_sysv_t),
+      code,
+      argc,
+      argv,
+      cleanup_func,
+      process);
+
+  /* if the user provided a function for the process then use it,
+     otherwise it is the context for maestro */
   if (code) {
 
-    xbt_assert2(getcontext(&(context->uc)) == 0,
-                "Error in context saving: %d (%s)", errno,
-                strerror(errno));
+    context->stack = SIMIX_context_stack_new();
+    getcontext(&(context->uc));
 
     context->uc.uc_link = NULL;
 
     context->uc.uc_stack.ss_sp =
-        pth_skaddr_makecontext(context->stack, CONTEXT_STACK_SIZE);
+        pth_skaddr_makecontext(context->stack, smx_context_stack_size);
 
     context->uc.uc_stack.ss_size =
-        pth_sksize_makecontext(context->stack, CONTEXT_STACK_SIZE);
+        pth_sksize_makecontext(context->stack, smx_context_stack_size);
 
 #ifdef HAVE_VALGRIND_VALGRIND_H
     context->valgrind_stack_id =
@@ -97,28 +146,33 @@ smx_ctx_sysv_create_context_sized(size_t size, xbt_main_func_t code,
                                 ((char *) context->uc.uc_stack.ss_sp) +
                                 context->uc.uc_stack.ss_size);
 #endif                          /* HAVE_VALGRIND_VALGRIND_H */
-
-    makecontext(&((smx_ctx_sysv_t) context)->uc, (void (*)())smx_ctx_sysv_wrapper,
-                sizeof(void*)/sizeof(int), context);
+    memcpy(ctx_addr, &context, sizeof(smx_ctx_sysv_t));
+    switch (CTX_ADDR_LEN) {
+    case 1:
+      makecontext(&context->uc, (void (*)())smx_ctx_sysv_wrapper,
+                  1, ctx_addr[0]);
+      break;
+    case 2:
+      makecontext(&context->uc, (void (*)())smx_ctx_sysv_wrapper,
+                  2, ctx_addr[0], ctx_addr[1]);
+      break;
+    default:
+      xbt_die("Ucontexts are not supported on this arch yet (addr len = %zu/%zu = %zu)",
+              sizeof(smx_ctx_sysv_t), sizeof(int), CTX_ADDR_LEN);
+    }
+  } else {
+    if (process != NULL && sysv_maestro_context == NULL)
+      sysv_maestro_context = context;
   }
 
-  return (smx_context_t) context;
-
-}
-
-static smx_context_t
-smx_ctx_sysv_create_context(xbt_main_func_t code, int argc, char **argv,
-    void_pfn_smxprocess_t cleanup_func,
-    void *data)
-{
-
-  return smx_ctx_sysv_create_context_sized(sizeof(s_smx_ctx_sysv_t),
-                                           code, argc, argv, cleanup_func,
-                                           data);
+  if(MC_is_active() && code)
+    MC_new_stack_area(context, ((smx_context_t)context)->process->name,
+                      &(context->uc), sizeof(s_smx_ctx_sysv_t));
 
+  return (smx_context_t) context;
 }
 
-void smx_ctx_sysv_free(smx_context_t context)
+static void smx_ctx_sysv_free(smx_context_t context)
 {
 
   if (context) {
@@ -127,63 +181,131 @@ void smx_ctx_sysv_free(smx_context_t context)
     VALGRIND_STACK_DEREGISTER(((smx_ctx_sysv_t)
                                context)->valgrind_stack_id);
 #endif                          /* HAVE_VALGRIND_VALGRIND_H */
-
+    SIMIX_context_stack_delete(((smx_ctx_sysv_t)context)->stack);
   }
   smx_ctx_base_free(context);
 }
 
-void smx_ctx_sysv_stop(smx_context_t context)
-{
-  smx_ctx_base_stop(context);
-
-  smx_ctx_sysv_suspend(context);
-}
-
-void smx_ctx_sysv_wrapper(smx_ctx_sysv_t context)
+static void smx_ctx_sysv_wrapper(int first, ...)
 { 
+  int ctx_addr[CTX_ADDR_LEN];
+  smx_ctx_sysv_t context;
+
+  ctx_addr[0] = first;
+  if (CTX_ADDR_LEN > 1) {
+    va_list ap;
+    int i;
+    va_start(ap, first);
+    for (i = 1; i < CTX_ADDR_LEN; i++)
+      ctx_addr[i] = va_arg(ap, int);
+    va_end(ap);
+  }
+  memcpy(&context, ctx_addr, sizeof(smx_ctx_sysv_t));
   (context->super.code) (context->super.argc, context->super.argv);
 
-  smx_ctx_sysv_stop((smx_context_t) context);
+  simix_global->context_factory->stop((smx_context_t) context);
 }
 
-void smx_ctx_sysv_suspend(smx_context_t context)
+static void smx_ctx_sysv_stop_serial(smx_context_t context)
 {
-  ucontext_t maestro_ctx =
-      ((smx_ctx_sysv_t) simix_global->maestro_process->context)->uc;
+  smx_ctx_base_stop(context);
+  smx_ctx_sysv_suspend_serial(context);
+}
 
-  int rv = swapcontext(&((smx_ctx_sysv_t) context)->uc, &maestro_ctx);
+static void smx_ctx_sysv_suspend_serial(smx_context_t context)
+{
+  /* determine the next context */
+  smx_context_t next_context;
+  unsigned long int i = sysv_process_index++;
+
+  if (i < xbt_dynar_length(simix_global->process_to_run)) {
+    /* execute the next process */
+    XBT_DEBUG("Run next process");
+    next_context = xbt_dynar_get_as(
+        simix_global->process_to_run,i, smx_process_t)->context;
+  }
+  else {
+    /* all processes were run, return to maestro */
+    XBT_DEBUG("No more process to run");
+    next_context = (smx_context_t) sysv_maestro_context;
+  }
+  SIMIX_context_set_current(next_context);
+  swapcontext(&((smx_ctx_sysv_t) context)->uc,
+      &((smx_ctx_sysv_t) next_context)->uc);
+}
 
-  xbt_assert0((rv == 0), "Context swapping failure");
+static void smx_ctx_sysv_resume_serial(smx_process_t first_process)
+{
+  smx_context_t context = first_process->context;
+  SIMIX_context_set_current(context);
+  swapcontext(&sysv_maestro_context->uc,
+      &((smx_ctx_sysv_t) context)->uc);
 }
 
-void smx_ctx_sysv_resume(smx_context_t new_context)
+static void smx_ctx_sysv_runall_serial(void)
 {
-  smx_ctx_sysv_t maestro =
-      (smx_ctx_sysv_t) simix_global->maestro_process->context;
+  smx_process_t first_process =
+      xbt_dynar_get_as(simix_global->process_to_run, 0, smx_process_t);
+  sysv_process_index = 1;
 
-  int rv =
-      swapcontext(&(maestro->uc), &((smx_ctx_sysv_t) new_context)->uc);
+  /* execute the first process */
+  smx_ctx_sysv_resume_serial(first_process);
+}
 
-  xbt_assert0((rv == 0), "Context swapping failure");
+static void smx_ctx_sysv_stop_parallel(smx_context_t context)
+{
+  smx_ctx_base_stop(context);
+  smx_ctx_sysv_suspend_parallel(context);
 }
 
-void smx_ctx_sysv_runall(xbt_swag_t processes)
+static void smx_ctx_sysv_suspend_parallel(smx_context_t context)
 {
-  smx_context_t old_context;
-  smx_process_t process;
-  
-  while((process = xbt_swag_extract(processes))){
-    old_context = smx_current_context;
-    smx_current_context = process->context;
-    smx_ctx_sysv_resume(smx_current_context);
-    smx_current_context = old_context;
+#ifdef CONTEXT_THREADS
+  /* determine the next context */
+  smx_process_t next_work = xbt_parmap_next(sysv_parmap);
+  smx_context_t next_context;
+  ucontext_t* next_stack;
+
+  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;
+  }
+  else {
+    /* all processes were run, go to the barrier */
+    XBT_DEBUG("No more processes to run");
+    unsigned long worker_id =
+        (unsigned long) xbt_os_thread_get_specific(sysv_worker_id_key);
+    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);
+  swapcontext(&((smx_ctx_sysv_t) context)->uc, next_stack);
+#endif
 }
 
-void smx_ctx_sysv_runall_parallel(xbt_swag_t processes)
+static void smx_ctx_sysv_resume_parallel(smx_process_t first_process)
 {
-  smx_process_t process;
-  while((process = xbt_swag_extract(processes))){
-    xbt_tpool_queue_job(tpool, (void_f_pvoid_t)smx_ctx_sysv_resume, process->context);
-  }
-}
\ No newline at end of file
+#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);
+  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;
+
+  smx_context_t context = first_process->context;
+  SIMIX_context_set_current(context);
+  swapcontext(worker_stack, &((smx_ctx_sysv_t) context)->uc);
+#endif
+}
+
+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);
+#endif
+}