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SubjectRe: Shrink the held_lock struct by using bitfields.
On Tue, Jan 02, 2007 at 06:35:58PM -0500, Dave Jones wrote:

Sent the wrong diff. Here's the fixed version...



Shrink the held_lock struct by using bitfields.
This shrinks task_struct on lockdep enabled kernels by 480 bytes.

Signed-off-by: Dave Jones <davej@redhat.com>

diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index ea097dd..ba81cce 100644
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -175,11 +175,11 @@ struct held_lock {
* The following field is used to detect when we cross into an
* interrupt context:
*/
- int irq_context;
- int trylock;
- int read;
- int check;
- int hardirqs_off;
+ unsigned char irq_context:1;
+ unsigned char trylock:1;
+ unsigned char read:2;
+ unsigned char check:1;
+ unsigned char hardirqs_off:1;
};

/*
--
http://www.codemonkey.org.uk
-
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