lguest: change virtio ring alignment.

PATCH New Rusty Russell 1 participant 1 message Nov 12, 2008

Subsystems (2)

Documentation KVM

lore

Share & tools

lore

Rusty Russell

author

2008-11-12 12:23 UTC #0 lore raw

PATCH 7/7 lguest: change virtio ring alignment.

This is just to test that the constant is wired through correctly.

lguest has no ABI so I could apply this patch, but it breaks the "don't be an asshole" rule.

Documentation/lguest/Makefile +2 -0

diff -r 19e5f3f3a4be Documentation/lguest/Makefile
@@ -4,5 +4,7 @@
 
 all: lguest
 
+lguest: ../../include/linux/lguest_launcher.h
+
 clean:
 	rm -f lguest

include/linux/lguest_launcher.h +2 -1

diff -r 19e5f3f3a4be include/linux/lguest_launcher.h
@@ -60,5 +60,6 @@
 	LHREQ_BREAK, /* + on/off flag (on blocks until someone does off) */
 };
 
-#define LGUEST_VRING_ALIGN	4096
+/* A cacheline is enough separation between producer and consumer. */
+#define LGUEST_VRING_ALIGN	128
 #endif /* _LINUX_LGUEST_LAUNCHER */