Changeset 436a0a5 in mainline for kernel/generic/src/proc

Timestamp:

2018-11-09T22:04:01Z (7 years ago)

Author:

Jiří Zárevúcky <zarevucky.jiri@…>

Branches:

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

Children:

95d45482

Parents:

88e43bc (diff), abf6c01 (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:

(merge) Reduce the number of blocking allocations in the kernel

Location:

kernel/generic/src/proc

Files:

• scheduler.c (modified) (2 diffs)
• task.c (modified) (1 diff)
• thread.c (modified) (6 diffs)

kernel/generic/src/proc/scheduler.c

@@ -134 +134 @@
 void scheduler_fpu_lazy_request(void)
 {
-restart:
         fpu_enable();
         irq_spinlock_lock(&CPU->lock, false);
@@ -153 +152 @@
                 fpu_context_restore(THREAD->saved_fpu_context);
         } else {
-                /* Allocate FPU context */
-                if (!THREAD->saved_fpu_context) {
-                        /* Might sleep */
-                        irq_spinlock_unlock(&THREAD->lock, false);
-                        irq_spinlock_unlock(&CPU->lock, false);
-                        THREAD->saved_fpu_context =
-                            (fpu_context_t *) slab_alloc(fpu_context_cache, 0);
-
-                        /* We may have switched CPUs during slab_alloc */
-                        goto restart;
-                }
                 fpu_init();
                 THREAD->fpu_context_exists = true;

kernel/generic/src/proc/task.c

@@ -199 +199 @@
 task_t *task_create(as_t *as, const char *name)
 {
-        task_t *task = (task_t *) slab_alloc(task_cache, 0);
-        if (task == NULL) {
+        task_t *task = (task_t *) slab_alloc(task_cache, FRAME_ATOMIC);
+        if (!task)
                 return NULL;
-        }
 
         task_create_arch(task);

kernel/generic/src/proc/thread.c

@@ -165 +165 @@
 
 #ifdef CONFIG_FPU
-#ifdef CONFIG_FPU_LAZY
-        thread->saved_fpu_context = NULL;
-#else /* CONFIG_FPU_LAZY */
-        thread->saved_fpu_context = slab_alloc(fpu_context_cache, kmflags);
+        thread->saved_fpu_context = slab_alloc(fpu_context_cache,
+            FRAME_ATOMIC | kmflags);
         if (!thread->saved_fpu_context)
                 return ENOMEM;
-#endif /* CONFIG_FPU_LAZY */
 #endif /* CONFIG_FPU */
 
@@ -200 +197 @@
         if (!stack_phys) {
 #ifdef CONFIG_FPU
-                if (thread->saved_fpu_context)
-                        slab_free(fpu_context_cache, thread->saved_fpu_context);
+                assert(thread->saved_fpu_context);
+                slab_free(fpu_context_cache, thread->saved_fpu_context);
 #endif
                 return ENOMEM;
@@ -226 +223 @@
 
 #ifdef CONFIG_FPU
-        if (thread->saved_fpu_context)
-                slab_free(fpu_context_cache, thread->saved_fpu_context);
+        assert(thread->saved_fpu_context);
+        slab_free(fpu_context_cache, thread->saved_fpu_context);
 #endif
 
@@ -342 +339 @@
     thread_flags_t flags, const char *name)
 {
-        thread_t *thread = (thread_t *) slab_alloc(thread_cache, 0);
+        thread_t *thread = (thread_t *) slab_alloc(thread_cache, FRAME_ATOMIC);
         if (!thread)
                 return NULL;
+
+        if (thread_create_arch(thread, flags) != EOK) {
+                slab_free(thread_cache, thread);
+                return NULL;
+        }
 
         /* Not needed, but good for debugging */
@@ -407 +409 @@
         udebug_thread_initialize(&thread->udebug);
 #endif
-
-        /* Might depend on previous initialization */
-        thread_create_arch(thread);
 
         if ((flags & THREAD_FLAG_NOATTACH) != THREAD_FLAG_NOATTACH)
@@ -654 +653 @@
 
         return waitq_sleep_timeout(&thread->join_wq, usec, flags, NULL);
+
+        // FIXME: join should deallocate the thread.
+        //        Current code calls detach after join, that's contrary to how
+        //        join is used in other threading APIs.
 }