On Wed, Aug 08, 2012 at 05:52:57PM -0700, Leo Alterman wrote:
> 64-bit glibc appears to avoid syscalls for clock_gettime(), so we can get
> higher resolution timing and avoid having a timer firing off SIGALRM
> without introducing extra overhead.
>
> Signed-off-by: Leo Alterman <lalter...@nicira.com>
"git am" reported some trailing whitespace:
Applying: timeval: On Linux x86-64 systems refresh time whenever it is
requested.
/home/blp/nicira/ovs/.git/rebase-apply/patch:108: trailing whitespace.
*
/home/blp/nicira/ovs/.git/rebase-apply/patch:112: trailing whitespace.
*
/home/blp/nicira/ovs/.git/rebase-apply/patch:121: trailing whitespace.
> +/* On Linux x86-64 systems, glibc avoids using syscalls for clock_gettime().
I don't think that this is a feature of glibc. I think that it is a
feature of the kernel system call interface, which includes a stub that
implements clock_gettime() without doing a user-to-supervisor ring
transition and thereby avoids most of the normal system call overhead.
> +#if defined __LP64__ && defined __linux__
> +#define CACHE_TIME 0
> +#else
> +#define CACHE_TIME 1
> +#endif
I think that __LP64__ is meant to indicate that the system has "long"
and pointer types that are 64-bits wide. (But I can't find it in the
usually comprehensive listing at predef.sf.net.) I think it would be
better to test for __x86_64__ instead.
In test-timeval.c please add {} around the conditional statements.
Thanks,
Ben.
_______________________________________________
dev mailing list
dev@openvswitch.org
http://openvswitch.org/mailman/listinfo/dev
