Commit 8477b55b authored Jul 14, 2006 by Vadim Lobanov Committed by Linus Torvalds Jul 14, 2006

[PATCH] i386: remove redundant might_sleep() in user accessors.



On i386, the user space accessor functions copy_from/to_user() both invoke
might_sleep(), do a quick sanity check, and then pass the work on to their
__copy_from/to_user() counterparts, which again invoke might_sleep().
Given that no actual work happens between these two calls, it is best to
eliminate one of the redundant might_sleep()s.

Signed-off-by: Vadim Lobanov <vlobanov@speakeasy.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

parent e78a887a

arch/i386/lib/usercopy.c

+0 −2

Original line number	Diff line number	Diff line
		@@ -843,7 +843,6 @@ unsigned long __copy_from_user_ll_nocache_nozero(void to, const void __user fr
		unsigned long
		copy_to_user(void __user to, const void from, unsigned long n)
		{
		might_sleep();
		BUG_ON((long) n < 0);
		if (access_ok(VERIFY_WRITE, to, n))
		n = __copy_to_user(to, from, n);
		@@ -870,7 +869,6 @@ EXPORT_SYMBOL(copy_to_user);
		unsigned long
		copy_from_user(void to, const void __user from, unsigned long n)
		{
		might_sleep();
		BUG_ON((long) n < 0);
		if (access_ok(VERIFY_READ, from, n))
		n = __copy_from_user(to, from, n);

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