xnu-1504.15.3.tar.gz

[apple/xnu.git] / osfmk / i386 / locks_i386.c

diff --git a/osfmk/i386/locks_i386.c b/osfmk/i386/locks_i386.c
index 3d3e5a09f3505070fe265d5ae0be1737c9b56d3e..8c715d086afaaa46d6e520c20f724f0893e627d2 100644 (file)
--- a/osfmk/i386/locks_i386.c
+++ b/osfmk/i386/locks_i386.c
@@ -77,15 +77,15 @@
 #include <kern/debug.h>
 #include <string.h>
 
-#include <i386/mp.h> /* mp_recent_debugger_activity() */
 #if    MACH_KDB
 #include <ddb/db_command.h>
 #include <ddb/db_output.h>
 #include <ddb/db_sym.h>
 #include <ddb/db_print.h>
 #endif /* MACH_KDB */
-
+#include <i386/machine_routines.h> /* machine_timeout_suspended() */
 #include <machine/machine_cpu.h>
+#include <i386/mp.h>
 
 #include <sys/kdebug.h>
 
@@ -319,6 +319,29 @@ usimple_lock_init(
 #endif
 }
 
+volatile uint32_t spinlock_owner_cpu = ~0;
+volatile usimple_lock_t spinlock_timed_out;
+
+static uint32_t spinlock_timeout_NMI(uintptr_t thread_addr) {
+       uint64_t deadline;
+       uint32_t i;
+
+       for (i = 0; i < real_ncpus; i++) {
+               if ((uintptr_t)cpu_data_ptr[i]->cpu_active_thread == thread_addr) {
+                       spinlock_owner_cpu = i;
+                       if ((uint32_t)cpu_number() == i)
+                               break;
+                       cpu_datap(i)->cpu_NMI_acknowledged = FALSE;
+                       cpu_NMI_interrupt(i);
+                       deadline = mach_absolute_time() + (LockTimeOut * 2);
+                       while (mach_absolute_time() < deadline && cpu_datap(i)->cpu_NMI_acknowledged == FALSE)
+                               cpu_pause();
+                       break;
+               }
+       }
+
+       return spinlock_owner_cpu;
+}
 
 /*
  *     Acquire a usimple_lock.
@@ -336,14 +359,20 @@ usimple_lock(
 
        OBTAIN_PC(pc);
        USLDBG(usld_lock_pre(l, pc));
-
-       if(!hw_lock_to(&l->interlock, LockTimeOutTSC))  {/* Try to get the lock
-                                                         * with a timeout */
+/* Try to get the lock with a timeout */
+       if(!hw_lock_to(&l->interlock, LockTimeOutTSC))  {
                boolean_t uslock_acquired = FALSE;
-               while (mp_recent_debugger_activity() &&
-                   !(uslock_acquired = hw_lock_to(&l->interlock, LockTimeOutTSC)));
-               if (uslock_acquired == FALSE)
-                       panic("Spinlock acquisition timed out: lock=%p, lock owner thread=0x%lx, current_thread: %p", l, (uintptr_t)l->interlock.lock_data, current_thread());
+               while (machine_timeout_suspended()) {
+                       enable_preemption();
+                       if ((uslock_acquired = hw_lock_to(&l->interlock, LockTimeOutTSC)))
+                               break;
+       }
+               if (uslock_acquired == FALSE) {
+                       uint32_t lock_cpu;
+                       spinlock_timed_out = l;
+                       lock_cpu = spinlock_timeout_NMI((uintptr_t)l->interlock.lock_data);
+                       panic("Spinlock acquisition timed out: lock=%p, lock owner thread=0x%lx, current_thread: %p, lock owner active on CPU 0x%x", l, (uintptr_t)l->interlock.lock_data, current_thread(), lock_cpu);
+               }
        }
        USLDBG(usld_lock_post(l, pc));
 #else