Merge branch 'atomics' into 'master'

Unified the atomic calls everywhere using the defined macros

Some more code clean-up. I have modified all the calls to __sync_* to use the defined atomic macros. Makes the code easier to read. 

Note that in the case of the timer function, moving to the defined macros changed the return value (++i instead of i++). But we don't use the return value anyway. 

Re-assign to me if you are happy to have this merged in.

See merge request !181

src/cell.c

@@ -269,7 +269,7 @@ int cell_locktree(struct cell *c) {
     /* Undo the holds up to finger. */
     for (struct cell *finger2 = c->parent; finger2 != finger;
          finger2 = finger2->parent)
-      __sync_fetch_and_sub(&finger2->hold, 1);
+      atomic_dec(&finger2->hold);
 
     /* Unlock this cell. */
     if (lock_unlock(&c->lock) != 0) error("Failed to unlock cell.");
@@ -309,7 +309,7 @@ int cell_glocktree(struct cell *c) {
     if (lock_trylock(&finger->glock) != 0) break;
 
     /* Increment the hold. */
-    __sync_fetch_and_add(&finger->ghold, 1);
+    atomic_inc(&finger->ghold);
 
     /* Unlock the cell. */
     if (lock_unlock(&finger->glock) != 0) error("Failed to unlock cell.");
@@ -327,7 +327,7 @@ int cell_glocktree(struct cell *c) {
     /* Undo the holds up to finger. */
     for (struct cell *finger2 = c->parent; finger2 != finger;
          finger2 = finger2->parent)
-      __sync_fetch_and_sub(&finger2->ghold, 1);
+      atomic_dec(&finger2->ghold);
 
     /* Unlock this cell. */
     if (lock_unlock(&c->glock) != 0) error("Failed to unlock cell.");
@@ -353,7 +353,7 @@ void cell_unlocktree(struct cell *c) {
 
   /* Climb up the tree and unhold the parents. */
   for (struct cell *finger = c->parent; finger != NULL; finger = finger->parent)
-    __sync_fetch_and_sub(&finger->hold, 1);
+    atomic_dec(&finger->hold);
 
   TIMER_TOC(timer_locktree);
 }
@@ -367,7 +367,7 @@ void cell_gunlocktree(struct cell *c) {
 
   /* Climb up the tree and unhold the parents. */
   for (struct cell *finger = c->parent; finger != NULL; finger = finger->parent)
-    __sync_fetch_and_sub(&finger->ghold, 1);
+    atomic_dec(&finger->ghold);
 
   TIMER_TOC(timer_locktree);
 }

src/lock.h

@@ -23,6 +23,7 @@
 #include <pthread.h>
 
 /* Includes. */
+#include "atomic.h"
 #include "inline.h"
 
 #ifdef PTHREAD_SPINLOCK
@@ -48,14 +49,14 @@
 #define lock_init(l) (*(l) = 0)
 #define lock_destroy(l) 0
 INLINE static int lock_lock(volatile int *l) {
-  while (__sync_val_compare_and_swap(l, 0, 1) != 0)
+  while (atomic_cas(l, 0, 1) != 0)
     ;
   // while( *l );
   return 0;
 }
-#define lock_trylock(l) ((*(l)) ? 1 : __sync_val_compare_and_swap(l, 0, 1))
-#define lock_unlock(l) (__sync_val_compare_and_swap(l, 1, 0) != 1)
-#define lock_unlock_blind(l) __sync_val_compare_and_swap(l, 1, 0)
+#define lock_trylock(l) ((*(l)) ? 1 : atomic_cas(l, 0, 1))
+#define lock_unlock(l) (atomic_cas(l, 1, 0) != 1)
+#define lock_unlock_blind(l) atomic_cas(l, 1, 0)
 #endif
 
 #endif /* SWIFT_LOCK_H */

src/map.c

@@ -18,15 +18,23 @@
  *
  ******************************************************************************/
 
-#include "map.h"
+/* Config parameters. */
+#include "../config.h"
+
+/* Some standard headers. */
 #include <stdio.h>
 #include <stdlib.h>
+
+/* This object's header. */
+#include "map.h"
+
+/* Local headers. */
+#include "atomic.h"
 #include "error.h"
 
 /**
  * @brief Mapping function to draw a specific cell (gnuplot).
  */
-
 void map_cells_plot(struct cell *c, void *data) {
 
   int depth = *(int *)data;
@@ -80,24 +88,21 @@ void map_cells_plot(struct cell *c, void *data) {
 /**
  * @brief Mapping function for checking if each part is in its box.
  */
+void map_check(struct part *p, struct cell *c, void *data) {
 
-/* void map_check ( struct part *p , struct cell *c , void *data ) {
-
-    if ( p->x[0] < c->loc[0] || p->x[0] > c->loc[0]+c->h[0] ||
-         p->x[0] < c->loc[0] || p->x[0] > c->loc[0]+c->h[0] ||
-         p->x[0] < c->loc[0] || p->x[0] > c->loc[0]+c->h[0] )
-        printf( "map_check: particle %i is outside of its box.\n" , p->id );
-
-    } */
+  if (p->x[0] < c->loc[0] || p->x[0] > c->loc[0] + c->h[0] ||
+      p->x[0] < c->loc[0] || p->x[0] > c->loc[0] + c->h[0] ||
+      p->x[0] < c->loc[0] || p->x[0] > c->loc[0] + c->h[0])
+    printf("map_check: particle %lld is outside of its box.\n", p->id);
+}
 
 /**
  * @brief Mapping function for neighbour count.
  */
-
 void map_cellcheck(struct cell *c, void *data) {
 
   int *count = (int *)data;
-  __sync_fetch_and_add(count, c->count);
+  atomic_add(count, c->count);
 
   /* Loop over all parts and check if they are in the cell. */
   for (int k = 0; k < c->count; k++) {
@@ -133,7 +138,6 @@ void map_cellcheck(struct cell *c, void *data) {
 /**
  * @brief Mapping function for maxdepth cell count.
  */
-
 void map_maxdepth(struct cell *c, void *data) {
 
   int maxdepth = ((int *)data)[0];
@@ -147,7 +151,6 @@ void map_maxdepth(struct cell *c, void *data) {
 /**
  * @brief Mapping function for neighbour count.
  */
-
 void map_count(struct part *p, struct cell *c, void *data) {
 
   double *wcount = (double *)data;
@@ -156,7 +159,6 @@ void map_count(struct part *p, struct cell *c, void *data) {
 
   *wcount += p->density.wcount;
 }
-
 void map_wcount_min(struct part *p, struct cell *c, void *data) {
 
   struct part **p2 = (struct part **)data;
@@ -188,7 +190,6 @@ void map_h_max(struct part *p, struct cell *c, void *data) {
 /**
  * @brief Mapping function for neighbour count.
  */
-
 void map_icount(struct part *p, struct cell *c, void *data) {
 
   // int *count = (int *)data;
@@ -201,7 +202,6 @@ void map_icount(struct part *p, struct cell *c, void *data) {
 /**
  * @brief Mapping function to print the particle position.
  */
-
 void map_dump(struct part *p, struct cell *c, void *data) {
 
   double *shift = (double *)data;

src/timers.h

@@ -23,6 +23,7 @@
 #define SWIFT_TIMERS_H
 
 /* Includes. */
+#include "atomic.h"
 #include "cycle.h"
 #include "inline.h"
 
@@ -71,7 +72,7 @@ extern ticks timers[timer_count];
 #define TIMER_TOC2(t) timers_toc(t, tic2)
 INLINE static ticks timers_toc(int t, ticks tic) {
   ticks d = (getticks() - tic);
-  __sync_add_and_fetch(&timers[t], d);
+  atomic_add(&timers[t], d);
   return d;
 }
 #else