[rtems commit] m68k: Use CPU_TIMESTAMP_USE_STRUCT_TIMESPEC

[Joel Sherrill]

The code is m68k and the comment is PowerPC.

Any guidance for the porting guide on what constitutes too expensive? There should be some general guidelines regarding when to pick a format bases on that.

Also.. This means that some ports will have 2038 issues at the score level. We have to address 64 bit time_t at some point.


On September 23, 2014 3:42:48 AM CDT, Sebastian Huber <sebh at rtems.org> wrote:
>Module:    rtems
>Branch:    master
>Commit:    5323247c3148a22baefb1590533972c401f7d745
>Changeset:
>http://git.rtems.org/rtems/commit/?id=5323247c3148a22baefb1590533972c401f7d745
>
>Author:    Sebastian Huber <sebastian.huber at embedded-brains.de>
>Date:      Tue Sep 23 08:01:56 2014 +0200
>
>m68k: Use CPU_TIMESTAMP_USE_STRUCT_TIMESPEC
>
>Converting 64-bit nanoseconds values into the common struct timeval or
>struct timespec formats requires a 64-bit division to get the seconds
>value.  Performance analysis of high network loads revealed that this
>is
>too costly on PowerPC.
>
>---
>
> cpukit/score/cpu/m68k/rtems/score/cpu.h |    2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
>
>diff --git a/cpukit/score/cpu/m68k/rtems/score/cpu.h
>b/cpukit/score/cpu/m68k/rtems/score/cpu.h
>index d222465..7d164f3 100644
>--- a/cpukit/score/cpu/m68k/rtems/score/cpu.h
>+++ b/cpukit/score/cpu/m68k/rtems/score/cpu.h
>@@ -102,7 +102,7 @@ extern "C" {
> #define CPU_STACK_GROWS_UP               FALSE
> #define CPU_STRUCTURE_ALIGNMENT          __attribute__ ((aligned (4)))
> 
>-#define CPU_TIMESTAMP_USE_INT64_INLINE TRUE
>+#define CPU_TIMESTAMP_USE_STRUCT_TIMESPEC TRUE
> 
> /*
>*  Define what is required to specify how the network to host
>conversion
>
>_______________________________________________
>vc mailing list
>vc at rtems.org
>http://lists.rtems.org/mailman/listinfo/vc

--joel
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.rtems.org/pipermail/devel/attachments/20140923/91bd2f71/attachment.html>