[console] Sleep while waiting for user input

Reduce CPU usage while waiting for user input. This is particularly important for virtual machines, where CPU is a shared resource. Reported-by: Alessandro Salvatori <alessandro@embrane.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
ipxe · Jul 24, 2012 · 183a70e · 183a70e
1 parent fb7c022
commit 183a70e
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/src/core/getkey.c b/src/core/getkey.c
@@ -24,6 +24,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
 #include <ipxe/process.h>
 #include <ipxe/keys.h>
 #include <ipxe/timer.h>
+#include <ipxe/nap.h>
 
 /** @file
  *
@@ -46,6 +47,7 @@ static int getchar_timeout ( unsigned long timeout ) {
 		step();
 		if ( iskey() )
 			return getchar();
+		cpu_nap();
 	}
 
 	return -1;