From: Matthew Wilcox <matthew@wil.cx>
Date: Fri, 29 Sep 2006 08:58:36 +0000 (-0700)
Subject: [PATCH] remove generic__raw_read_trylock()
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=910067d188d56d80801b71b0ca1f73aa400c7b8c;p=linux-beck.git

[PATCH] remove generic__raw_read_trylock()

If the cpu has the lock held for write, is interrupted, and the interrupt
handler calls read_trylock(), it's an instant deadlock.

Now, Dave Miller has subsequently pointed out that we don't have any
situations where this can occur.  Nevertheless, we should delete
generic__raw_read_lock (and its associated EXPORT to make Arjan happy) so that
nobody thinks they can use it.

Acked-by: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---

diff --git a/kernel/spinlock.c b/kernel/spinlock.c
index 9644a41e0bef..d48143eafbfd 100644
--- a/kernel/spinlock.c
+++ b/kernel/spinlock.c
@@ -21,17 +21,6 @@
 #include <linux/debug_locks.h>
 #include <linux/module.h>
 
-/*
- * Generic declaration of the raw read_trylock() function,
- * architectures are supposed to optimize this:
- */
-int __lockfunc generic__raw_read_trylock(raw_rwlock_t *lock)
-{
-	__raw_read_lock(lock);
-	return 1;
-}
-EXPORT_SYMBOL(generic__raw_read_trylock);
-
 int __lockfunc _spin_trylock(spinlock_t *lock)
 {
 	preempt_disable();