[syslinux:lwip] thread: add support for locking the scheduler

[syslinux-bot for H. Peter Anvin]

Commit-ID:  cd8b37053cc36014379fefdecf1d409bc7dc5b45
Gitweb:     http://syslinux.zytor.com/commit/cd8b37053cc36014379fefdecf1d409bc7dc5b45
Author:     H. Peter Anvin <hpa at zytor.com>
AuthorDate: Thu, 10 Sep 2009 17:50:26 -0700
Committer:  Eric W. Biederman <ebiederm at xmission.com>
CommitDate: Sat, 9 Apr 2011 18:27:06 -0700

thread: add support for locking the scheduler

Add support for locking the scheduler; this is needed for the pm
return hook to operate properly.

Signed-off-by: H. Peter Anvin <hpa at zytor.com>


---
 core/include/core.h    |    3 +++
 core/include/thread.h  |    3 +++
 core/thread/schedule.c |   10 ++++++++++
 core/thread/timeout.c  |    2 ++
 4 files changed, 18 insertions(+), 0 deletions(-)

diff --git a/core/include/core.h b/core/include/core.h
index a593c26..62a61f6 100644
--- a/core/include/core.h
+++ b/core/include/core.h
@@ -18,6 +18,9 @@ extern char ConfigFile[];
 /* diskstart.inc isolinux.asm*/
 extern void getlinsec(void);
 
+/* pm.inc */
+extern void (*core_pm_hook)(void);
+
 /* getc.inc */
 extern void core_open(void);
 
diff --git a/core/include/thread.h b/core/include/thread.h
index 55a3ed7..7d34676 100644
--- a/core/include/thread.h
+++ b/core/include/thread.h
@@ -28,6 +28,9 @@ struct thread {
     int prio;
 };
 
+extern int __schedule_lock;
+extern bool __need_schedule;
+void __thread_process_timeouts(void);
 void __schedule(void);
 void __switch_to(struct thread *);
 void thread_yield(void);
diff --git a/core/thread/schedule.c b/core/thread/schedule.c
index b139c43..1bc02f6 100644
--- a/core/thread/schedule.c
+++ b/core/thread/schedule.c
@@ -1,6 +1,9 @@
 #include <sys/cpu.h>
 #include "thread.h"
 
+int __schedule_lock;
+bool __need_schedule;
+
 /*
  * __schedule() should only be called with interrupts locked out!
  */
@@ -9,6 +12,13 @@ void __schedule(void)
     struct thread *curr = current();
     struct thread *st, *nt, *best;
 
+    if (__schedule_lock) {
+	__need_schedule = true;
+	return;
+    }
+
+    __need_schedule = false;
+
     best = NULL;
 
     /*
diff --git a/core/thread/timeout.c b/core/thread/timeout.c
index 2ca0782..409ad6d 100644
--- a/core/thread/timeout.c
+++ b/core/thread/timeout.c
@@ -33,6 +33,8 @@ void __thread_process_timeouts(void)
 
 		t->blocked = NULL;
 		block->timed_out = true;
+
+		__schedule();	/* Normally sets just __need_schedule */
 	    }
 	}
     }