Changeset 827d73f in mainline for uspace/lib/libc/generic/fibril.c

Timestamp:

2010-02-12T14:09:22Z (14 years ago)

Author:

Lukas Mejdrech <lukasmejdrech@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

a70bda4

Parents:

918e9910 (diff), e70edd1 (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merged the actual head

File:

• uspace/lib/libc/generic/fibril.c (modified) (9 diffs)

uspace/lib/libc/generic/fibril.c

@@ -41 +41 @@
 #include <unistd.h>
 #include <stdio.h>
+#include <arch/barrier.h>
 #include <libarch/faddr.h>
 #include <futex.h>
@@ -133 +134 @@
 int fibril_switch(fibril_switch_type_t stype)
 {
-        fibril_t *srcf, *dstf;
         int retval = 0;
         
         futex_down(&fibril_futex);
-
+        
         if (stype == FIBRIL_PREEMPT && list_empty(&ready_list))
                 goto ret_0;
-
+        
         if (stype == FIBRIL_FROM_MANAGER) {
-                if (list_empty(&ready_list) && list_empty(&serialized_list))
+                if ((list_empty(&ready_list)) && (list_empty(&serialized_list)))
                         goto ret_0;
+                
                 /*
                  * Do not preempt if there is not enough threads to run the
                  * ready fibrils which are not serialized.
                  */
-                if (list_empty(&serialized_list) &&
-                    threads_in_manager <= serialized_threads) {
+                if ((list_empty(&serialized_list)) &&
+                    (threads_in_manager <= serialized_threads)) {
                         goto ret_0;
                 }
         }
+        
         /* If we are going to manager and none exists, create it */
-        if (stype == FIBRIL_TO_MANAGER || stype == FIBRIL_FROM_DEAD) {
+        if ((stype == FIBRIL_TO_MANAGER) || (stype == FIBRIL_FROM_DEAD)) {
                 while (list_empty(&manager_list)) {
                         futex_up(&fibril_futex);
@@ -162 +164 @@
         }
         
-        srcf = __tcb_get()->fibril_data;
+        fibril_t *srcf = __tcb_get()->fibril_data;
         if (stype != FIBRIL_FROM_DEAD) {
+                
                 /* Save current state */
                 if (!context_save(&srcf->ctx)) {
                         if (serialization_count)
                                 srcf->flags &= ~FIBRIL_SERIALIZED;
+                        
                         if (srcf->clean_after_me) {
                                 /*
@@ -173 +177 @@
                                  * restored context here.
                                  */
-                                void *stack = srcf->clean_after_me->stack; 
+                                void *stack = srcf->clean_after_me->stack;
                                 if (stack) {
                                         /*
@@ -188 +192 @@
                                 srcf->clean_after_me = NULL;
                         }
+                        
                         return 1;       /* futex_up already done here */
                 }
-
+                
                 /* Save myself to the correct run list */
                 if (stype == FIBRIL_PREEMPT)
@@ -197 +202 @@
                         list_append(&srcf->link, &manager_list);
                         threads_in_manager--;
-                } else {        
+                } else {
                         /*
                          * If stype == FIBRIL_TO_MANAGER, don't put ourselves to
@@ -206 +211 @@
         }
         
+        /* Avoid srcf being clobbered by context_save() */
+        srcf = __tcb_get()->fibril_data;
+        
         /* Choose a new fibril to run */
-        if (stype == FIBRIL_TO_MANAGER || stype == FIBRIL_FROM_DEAD) {
+        fibril_t *dstf;
+        if ((stype == FIBRIL_TO_MANAGER) || (stype == FIBRIL_FROM_DEAD)) {
                 dstf = list_get_instance(manager_list.next, fibril_t, link);
                 if (serialization_count && stype == FIBRIL_TO_MANAGER) {
@@ -214 +223 @@
                 }
                 threads_in_manager++;
-
+                
                 if (stype == FIBRIL_FROM_DEAD) 
                         dstf->clean_after_me = srcf;
@@ -228 +237 @@
         }
         list_remove(&dstf->link);
-
+        
         futex_up(&fibril_futex);
         context_restore(&dstf->ctx);
         /* not reached */
-
+        
 ret_0:
         futex_up(&fibril_futex);