xnu-2050.48.11.tar.gz

[apple/xnu.git] / osfmk / kern / wait_queue.h

diff --git a/osfmk/kern/wait_queue.h b/osfmk/kern/wait_queue.h
index 030e82d282bc7867f9d0ddd7650f1ba784667b70..fc91a60afbecfb60282d4de780004decdaab21e6 100644 (file)
--- a/osfmk/kern/wait_queue.h
+++ b/osfmk/kern/wait_queue.h
@@ -36,15 +36,17 @@
 #include <mach/kern_return.h>          /* for kern_return_t */
 
 #include <kern/kern_types.h>           /* for wait_queue_t */
+#include <kern/queue.h>
 
 #include <sys/cdefs.h>
 
 #ifdef MACH_KERNEL_PRIVATE
 
 #include <kern/lock.h>
-#include <kern/queue.h>
-#include <machine/cpu_number.h>
+#include <mach/branch_predicates.h>
 
+#include <machine/cpu_number.h>
+#include <machine/machine_routines.h> /* machine_timeout_suspended() */
 /*
  *     wait_queue_t
  *     This is the definition of the common event wait queue
@@ -152,7 +154,7 @@ typedef struct _wait_queue_link {
 #define wait_queue_lock_try(wq) (hw_lock_try(&(wq)->wq_interlock))
 
 /* For x86, the hardware timeout is in TSC units. */
-#if defined(i386)
+#if defined(i386) || defined(x86_64)
 #define        hwLockTimeOut LockTimeOutTSC
 #else
 #define        hwLockTimeOut LockTimeOut
@@ -165,11 +167,25 @@ typedef struct _wait_queue_link {
  */
 
 static inline void wait_queue_lock(wait_queue_t wq) {
-       if (!hw_lock_to(&(wq)->wq_interlock, hwLockTimeOut * 2))
-               panic("wait queue deadlock - wq=%p, cpu=%d\n", wq, cpu_number(
-));
+       if (__improbable(hw_lock_to(&(wq)->wq_interlock, hwLockTimeOut * 2) == 0)) {
+               boolean_t wql_acquired = FALSE;
+
+               while (machine_timeout_suspended()) {
+#if    defined(__i386__) || defined(__x86_64__)
+/*
+ * i386/x86_64 return with preemption disabled on a timeout for
+ * diagnostic purposes.
+ */
+                       mp_enable_preemption();
+#endif
+                       if ((wql_acquired = hw_lock_to(&(wq)->wq_interlock, hwLockTimeOut * 2)))
+                               break;
+               }
+               if (wql_acquired == FALSE)
+                       panic("wait queue deadlock - wq=%p, cpu=%d\n", wq, cpu_number());
+       }
 }
- 
+
 static inline void wait_queue_unlock(wait_queue_t wq) {
        assert(wait_queue_held(wq));
        hw_lock_unlock(&(wq)->wq_interlock);
@@ -255,12 +271,11 @@ static inline uint32_t wq_hash(char *key)
        hash ^= (hash >> 11);
        hash += (hash << 15);
 
+       hash &= (num_wait_queues - 1);
        return hash;
 }
 
-/* TBD: It should be possible to eliminate the divide here */
-#define       wait_hash(event)                                         \
-       (wq_hash((char *)&event) % (num_wait_queues))
+#define        wait_hash(event) wq_hash((char *)&event) 
 
 #endif /* MACH_KERNEL_PRIVATE */
 
@@ -314,6 +329,28 @@ extern kern_return_t wait_queue_unlink_all(
 extern kern_return_t wait_queue_set_unlink_all(
                        wait_queue_set_t set_queue);
 
+#ifdef XNU_KERNEL_PRIVATE
+extern kern_return_t wait_queue_set_unlink_one(
+                       wait_queue_set_t set_queue,
+                       wait_queue_link_t link);
+
+extern kern_return_t wait_queue_unlink_nofree(
+                       wait_queue_t wait_queue,
+                       wait_queue_set_t set_queue,
+                       wait_queue_link_t *wqlp);
+
+extern kern_return_t wait_queue_unlink_all_nofree(
+                       wait_queue_t wait_queue,
+                       queue_t links);
+
+extern kern_return_t wait_queue_set_unlink_all_nofree(
+                       wait_queue_set_t set_queue,
+                       queue_t links);
+
+extern wait_queue_link_t wait_queue_link_allocate(void);
+
+#endif /* XNU_KERNEL_PRIVATE */
+
 /* legacy API */
 kern_return_t wait_queue_sub_init(
                        wait_queue_set_t set_queue,
@@ -373,7 +410,8 @@ extern wait_result_t wait_queue_assert_wait(
 extern kern_return_t wait_queue_wakeup_one(
                        wait_queue_t wait_queue,
                        event_t wake_event,
-                       wait_result_t result);
+                       wait_result_t result,
+                       int priority);
 
 /* wakeup all the threads waiting on <wait_queue,event> pair */
 extern kern_return_t wait_queue_wakeup_all(