From: Samuel Thibault <samuel.thibault@eu.citrix.com>
Subject: [PATCH] [Mini-OS] Make wake_up callback-safe
Date: Fri, 23 Nov 2007 16:59:39 +0000
Message-ID: <20071123165939.GA12313@implementation.uk.xensource.com>
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As it may compete with event handlers waking wait queues, wake_up needs
to be callback-safe.

Signed-off-by: Samuel Thibault <samuel.thibault@citrix.com>

diff -r f2711b7eae95 -r 36bf1e737b87 extras/mini-os/include/wait.h
--- a/extras/mini-os/include/wait.h	Thu Nov 22 19:55:42 2007 +0000
+++ b/extras/mini-os/include/wait.h	Fri Nov 23 13:21:02 2007 +0000
@@ -57,13 +57,16 @@
 
 static inline void wake_up(struct wait_queue_head *head)
 {
+    unsigned long flags;
     struct list_head *tmp, *next;
+    local_irq_save(flags);
     list_for_each_safe(tmp, next, &head->thread_list)
     {
          struct wait_queue *curr;
          curr = list_entry(tmp, struct wait_queue, thread_list);
          wake(curr->thread);
     }
+    local_irq_restore(flags);
 }
 
 #define add_waiter(w, wq) do {  \