Changeset f76fed4 in mainline for generic/src

Timestamp:

2006-03-03T00:20:31Z (19 years ago)

Author:

Ondrej Palkovsky <ondrap@…>

Branches:

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

Children:

09c18f78

Parents:

ddcf365

Message:

Added lazy fpu context allocation.

• threads that don't use fpu, don't get allocated fpu context
• fpu context alignment on AMD64 nicely disappeared

Location:

generic/src/proc

Files:

• scheduler.c (modified) (6 diffs)
• thread.c (modified) (4 diffs)

generic/src/proc/scheduler.c

@@ -64 +64 @@
 {
         before_thread_runs_arch();
-        #ifdef CONFIG_FPU_LAZY
+#ifdef CONFIG_FPU_LAZY
         if(THREAD==CPU->fpu_owner) 
                 fpu_enable();
         else
                 fpu_disable(); 
-        #else
+#else
         fpu_enable();
         if (THREAD->fpu_context_exists)
-                fpu_context_restore(&(THREAD->saved_fpu_context));
+                fpu_context_restore(THREAD->saved_fpu_context);
         else {
-                fpu_init(&(THREAD->saved_fpu_context));
+                fpu_init();
                 THREAD->fpu_context_exists=1;
         }
-        #endif
+#endif
 }
 
@@ -103 +103 @@
         if (CPU->fpu_owner != NULL) {  
                 spinlock_lock(&CPU->fpu_owner->lock);
-                fpu_context_save(&CPU->fpu_owner->saved_fpu_context);
+                fpu_context_save(CPU->fpu_owner->saved_fpu_context);
                 /* don't prevent migration */
                 CPU->fpu_owner->fpu_context_engaged=0; 
@@ -111 +111 @@
         spinlock_lock(&THREAD->lock);
         if (THREAD->fpu_context_exists) {
-                fpu_context_restore(&THREAD->saved_fpu_context);
+                fpu_context_restore(THREAD->saved_fpu_context);
         } else {
-                fpu_init(&(THREAD->saved_fpu_context));
+                /* Allocate FPU context */
+                if (!THREAD->saved_fpu_context) {
+                        /* Might sleep */
+                        spinlock_unlock(&THREAD->lock);
+                        THREAD->saved_fpu_context = slab_alloc(fpu_context_slab,
+                                                               0);
+                        spinlock_lock(&THREAD->lock);
+                }
+                fpu_init();
                 THREAD->fpu_context_exists=1;
         }
@@ -275 +283 @@
         if (THREAD) {
                 spinlock_lock(&THREAD->lock);
-                #ifndef CONFIG_FPU_LAZY
-                fpu_context_save(&(THREAD->saved_fpu_context));
-                #endif
+#ifndef CONFIG_FPU_LAZY
+                fpu_context_save(THREAD->saved_fpu_context);
+#endif
                 if (!context_save(&THREAD->saved_context)) {
                         /*
@@ -422 +430 @@
                         as_switch(as1, as2);
                 }
-                TASK = THREAD->task;    
+                TASK = THREAD->task;
         }
 
         THREAD->state = Running;
 
-        #ifdef SCHEDULER_VERBOSE
+#ifdef SCHEDULER_VERBOSE
         printf("cpu%d: tid %d (priority=%d,ticks=%d,nrdy=%d)\n", CPU->id, THREAD->tid, THREAD->priority, THREAD->ticks, atomic_get(&CPU->nrdy));
-        #endif  
+#endif  
 
         /*
@@ -547 +555 @@
                                  */
                                 spinlock_lock(&t->lock);
-                                #ifdef KCPULB_VERBOSE
+#ifdef KCPULB_VERBOSE
                                 printf("kcpulb%d: TID %d -> cpu%d, nrdy=%d, avg=%d\n", CPU->id, t->tid, CPU->id, atomic_get(&CPU->nrdy), atomic_get(&nrdy) / config.cpu_active);
-                                #endif
+#endif
                                 t->flags |= X_STOLEN;
                                 spinlock_unlock(&t->lock);

generic/src/proc/thread.c

@@ -64 +64 @@
 
 static slab_cache_t *thread_slab;
+#ifdef ARCH_HAS_FPU
+slab_cache_t *fpu_context_slab;
+#endif
 
 
@@ -104 +107 @@
         link_initialize(&t->threads_link);
         
+#ifdef ARCH_HAS_FPU
+#  ifdef CONFIG_FPU_LAZY
+        t->saved_fpu_context = NULL;
+#  else
+        t->saved_fpu_context = slab_alloc(fpu_context_slab,kmflags);
+        if (!t->saved_fpu_context)
+                return -1;
+#  endif
+#endif  
+
         pfn = frame_alloc_rc(ONE_FRAME, FRAME_KA | kmflags,&status);
-        if (status)
+        if (status) {
+#ifdef ARCH_HAS_FPU
+                if (t->saved_fpu_context)
+                        slab_free(fpu_context_slab,t->saved_fpu_context);
+#endif
                 return -1;
+        }
         t->kstack = (__u8 *)PA2KA(PFN2ADDR(pfn));
 
@@ -118 +136 @@
 
         frame_free(ADDR2PFN(KA2PA(t->kstack)));
+#ifdef ARCH_HAS_FPU
+        if (t->saved_fpu_context)
+                slab_free(fpu_context_slab,t->saved_fpu_context);
+#endif
         return 1; /* One page freed */
 }
@@ -133 +155 @@
                                         sizeof(thread_t),0, 
                                         thr_constructor, thr_destructor, 0);
+#ifdef ARCH_HAS_FPU
+        fpu_context_slab = slab_cache_create("fpu_slab",
+                                             sizeof(fpu_context_t),
+                                             FPU_CONTEXT_ALIGN,
+                                             NULL, NULL, 0);
+#endif
 }