lkml.org 
[lkml]   [2024]   [Jan]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCHv3 net-next 2/3] ptp: add ioctl interface for ptp_gettimex64any()
On Fri, Jan 5, 2024 at 8:55 PM Richard Cochran <richardcochran@gmail.com> wrote:
>
> On Fri, Jan 05, 2024 at 09:51:40AM -0800, Mahesh Bandewar (महेश बंडेवार) wrote:
>
> > POSIX clocks are employed in this series for syscall width
> > measurement, potentially leading to misunderstandings about
> > overlapping functionality. However, their roles are distinct and serve
> > different purposes.
>
> I don't see any difference in purposes. The multi_clock_gettime call
> is a more general solution. Thus it will obviate the need for any new
> PTP ioctls.
>

I disagree! NICs inherently benefit from bundled PTP devices due to
their superior low-latency, low-overhead, and precise TX/RX
timestamping capabilities. For demanding systems requiring increased
capacity, multiple NICs from various vendors are often deployed.
However, disciplining these diverse PTP devices across the host
demands a flexible approach; a general purpose syscall is not an
answer. The current PHC implementation using ioctls through exported
ptp devices (/dev/ptpX) provides a solid foundation that is per device
(/per NIC).

This series is providing another piece in an existing suite of methods
used for disciplining / precision tuning (along with adjfine, adjtime,
gettime etc.) This addition is to take that precision even further.

Having a general solution for posix timers is a nice addition.
However, expecting a general purpose syscall to eliminate need for
device ioctl is an unreasonable expectation.

Thanks,
--mahesh..

> Thanks,
> Richard

\
 
 \ /
  Last update: 2024-01-06 09:10    [W:0.107 / U:0.380 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site