Changes in kernel/generic/src/proc/thread.c [b169619:c7326f21] in mainline

File:

• kernel/generic/src/proc/thread.c (modified) (6 diffs)

kernel/generic/src/proc/thread.c

@@ -62 +62 @@
 #include <arch/faddr.h>
 #include <atomic.h>
-#include <memw.h>
+#include <mem.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -231 +231 @@
         irq_spinlock_lock(&thread->lock, true);
         thread->cpu = cpu;
-        thread->nomigrate++;
+        thread->wired = true;
         irq_spinlock_unlock(&thread->lock, true);
 }
@@ -259 +259 @@
             ++thread->priority : thread->priority;
 
-        /* Prefer the CPU on which the thread ran last */
-        cpu_t *cpu = thread->cpu ? thread->cpu : CPU;
+        cpu_t *cpu;
+        if (thread->wired || thread->nomigrate || thread->fpu_context_engaged) {
+                /* Cannot ready to another CPU */
+                assert(thread->cpu != NULL);
+                cpu = thread->cpu;
+        } else if (thread->stolen) {
+                /* Ready to the stealing CPU */
+                cpu = CPU;
+        } else if (thread->cpu) {
+                /* Prefer the CPU on which the thread ran last */
+                assert(thread->cpu != NULL);
+                cpu = thread->cpu;
+        } else {
+                cpu = CPU;
+        }
 
         thread->state = Ready;
@@ -335 +348 @@
         thread->priority = -1;          /* Start in rq[0] */
         thread->cpu = NULL;
+        thread->wired = false;
         thread->stolen = false;
         thread->uspace =
@@ -355 +369 @@
 
         thread->fpu_context_exists = false;
+        thread->fpu_context_engaged = false;
 
         odlink_initialize(&thread->lthreads);
@@ -411 +426 @@
 
         assert((thread->state == Exiting) || (thread->state == Lingering));
+        assert(thread->cpu);
 
         /* Clear cpu->fpu_owner if set to this thread. */
-#ifdef CONFIG_FPU_LAZY
-        if (thread->cpu) {
-                /*
-                 * We need to lock for this because the old CPU can concurrently try
-                 * to dump this thread's FPU state, in which case we need to wait for
-                 * it to finish. An atomic compare-and-swap wouldn't be enough.
-                 */
-                irq_spinlock_lock(&thread->cpu->fpu_lock, false);
-
-                thread_t *owner = atomic_load_explicit(&thread->cpu->fpu_owner,
-                    memory_order_relaxed);
-
-                if (owner == thread) {
-                        atomic_store_explicit(&thread->cpu->fpu_owner, NULL,
-                            memory_order_relaxed);
-                }
-
-                irq_spinlock_unlock(&thread->cpu->fpu_lock, false);
-        }
-#endif
+        irq_spinlock_lock(&thread->cpu->lock, false);
+        if (thread->cpu->fpu_owner == thread)
+                thread->cpu->fpu_owner = NULL;
+        irq_spinlock_unlock(&thread->cpu->lock, false);
 
         interrupts_restore(ipl);