Date: Fri, 02 Sep 2016 12:22:42 -0700 From: John Baldwin <jhb@freebsd.org> To: FreeBSD-arch Arch <freebsd-arch@freebsd.org> Subject: pause_ms() wrapper Message-ID: <2960854.iLOY0Gxipb@ralph.baldwin.cx>
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Figuring out the 3 arguments required for pause_sbt() can be a bit
non-obvious (at least to me). To that end, I'd like to have a simple
wrapper around pause_sbt() that accepts milliseconds. It would align
itself on hardclock similar to the hz-based wrapper. OTOH, we could
change the implementation at some point to use something more resaonable
in terms of precision, etc. However, most of the time when I want to
sleep for N milliseconds (or N microseconds) due to some hardware spec,
I don't really have a strong opinion on the precision. Having all the
callers try to figure out a precision would seem to inevitably result
in inconsistencies. To start with I'd like to just add this:
#define pause_ms(wmesg, msecs) \
pause_sbt((wmesg), SBT_1MS * (msecs), 0, C_HARDCLOCK)
Which you can use as 'pause_ms("pcieflr", 100);'.
Are there any objections? Do people want other wrappers? Should we
use more nuanced math similar to what was done in r296775?
--
John Baldwin
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