Staging: lustre: lnet: lnet: Better cookie gen

api-ni.c uses do_gettimeofday to get a 'cookie' or timestamp.
This patch replaces it with ktime_get_ns for the following reasons:
1. ktime_get_ns returns a __u64 which is safer than 'struct timeval'
which will overflow on 32-bit systems in year 2038 and beyond.
2. Improved resolution: nsecs instead of usecs.
3. Reduced compute: ktime_get_ns is faster than the multiply/add
   combination used in this function

Signed-off-by: Tina Ruchandani <ruchandani.tina@gmail.com>
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Tina Ruchandani 2014-10-30 14:35:01 -07:00 committed by Greg Kroah-Hartman
parent 60444139a0
commit 9056be3054
1 changed files with 4 additions and 11 deletions
drivers/staging/lustre/lnet/lnet

View File

@ -37,6 +37,7 @@
#define DEBUG_SUBSYSTEM S_LNET
#include "../../include/linux/lnet/lib-lnet.h"
#include <linux/log2.h>
#include <linux/ktime.h>
#define D_LNI D_CONSOLE
@ -417,17 +418,9 @@ static __u64
lnet_create_interface_cookie(void)
{
/* NB the interface cookie in wire handles guards against delayed
* replies and ACKs appearing valid after reboot. Initialisation time,
* even if it's only implemented to millisecond resolution is probably
* easily good enough. */
struct timeval tv;
__u64 cookie;
do_gettimeofday(&tv);
cookie = tv.tv_sec;
cookie *= 1000000;
cookie += tv.tv_usec;
return cookie;
* replies and ACKs appearing valid after reboot.
*/
return ktime_get_ns();
}
static char *