Commit 11dd2a97 authored Oct 30, 2014 by Tina Ruchandani Committed by Greg Kroah-Hartman Nov 03, 2014

Staging: lustre: lnet: Improve 'incarnation' stamp

ksock_net_t uses a __u64 quantity as an 'incarnation' timestamp. This is also
passed on in hello messages and used to detect if a reboot has occurred.
This 'incarnation' is obtained using do_gettimeofday.It is only used in equality
checks, so the absolute value does not matter.

This patch replaces do_gettimeofday 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. 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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent b7c12ca4

drivers/staging/lustre/lnet/klnds/socklnd/socklnd.c

+3 −8

Original line number	Diff line number	Diff line
		@@ -2348,16 +2348,11 @@ ksocknal_base_shutdown(void)
		static __u64
		ksocknal_new_incarnation (void)
		{
		struct timeval tv;

		/* The incarnation number is the time this module loaded and it
		* identifies this particular instance of the socknal. Hopefully
		* we won't be able to reboot more frequently than 1MHz for the
		* foreseeable future :) */

		do_gettimeofday(&tv);

		return (((__u64)tv.tv_sec) * 1000000) + tv.tv_usec;
		* identifies this particular instance of the socknal.
		*/
		return ktime_get_ns();
		}

		static int