Search Linux Wireless

Re: [PATCH 1/3] mac80211: move mesh sync beacon handler into neighbour_update

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Mon, 2013-02-18 at 16:07 +0100, Marco Porsch wrote:

> > I guess you can tell I'm not in a good mood today. I think any use of
> > get_tsf() for operation is a complete waste of time, there's no way you
> > can get the timings correct. You could be preempted, and suddenly sleep
> > for a few tens or hundreds milliseconds, so none of this makes any
> > sense... To properly do it you have to do calculations in relative times
> > and let the device apply them.
> 
> I don't get your last sentence here. Maybe you can elaborate?

I'm saying what could happens is this:

 tsf = drv_get_tsf()
 [be preempted, 100ms later]
 do_something_with(tsf)

so I think using drv_get_tsf() is pretty much always wrong.


> Concerning timestamp vs. TSF usage; wow - I tested it when using the 
> timestamp value for TBTT scheduling. Works fine. Works even better than 
> TSF as it slightly reduces the measured wakeup overhead.
> 
> Hm, I was sure the TSF as in *now* would be more appropriate than the 
> TSF at receipt time... But either way, if it works better and is less 
> ugly, it is a win-win =)
> 
> I'll send an updated patch with the more intuitive API.

:)

johannes

--
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Linux Host AP]     [ATH6KL]     [Linux Wireless Personal Area Network]     [Linux Bluetooth]     [Linux Netdev]     [Kernel Newbies]     [Linux Kernel]     [IDE]     [Git]     [Netfilter]     [Bugtraq]     [Yosemite Hiking]     [MIPS Linux]     [ARM Linux]     [Linux RAID]

  Powered by Linux