(10) (M) RFR: 8174231: Factor out and share PlatformEvent and Parker code for POSIX systems (original) (raw)

Robbin Ehn robbin.ehn at oracle.com
Fri May 19 09:25:13 UTC 2017

On 05/19/2017 11:07 AM, David Holmes wrote:

They have to be as there are three cases: 1. Relative wait using CLOCKMONOTONIC 2. Relative wait using gettimeofday() 3. Absolute wait using gettimeofday()

Please consider something like:

#ifdef SUPPORTSCLOCKMONOTONIC if (useclockmonotoniccondattr && !isAbsolute) { // Why aren't we using this when not isAbsolute is set? // I suggest removing that check from this if and use monotonic for that also. Absolute waits have to be based on wall-clock time and follow any adjustments made to wall clock time. In contrast relative waits should never be affected by wall-clock time adjustments hence the use of CLOCKMONOTONIC when available. In Java the relative timed-waits are: - Thread.sleep(ms) - Object.wait(ms)/wait(ms,ns) - LockSupport.parkNanos(ns) (and all the j.u.c blocking methods built on top of it) While the only absolute timed-wait we have is the LockSupport.parkUntil method(s). Hope that clarifies things.

Yes thanks!

But you can still re-factoring to something similar to what I suggested and two of the calculation should be the same just ns vs us, correct? Leaving the if statement with the "!isAbsolute" check, in my head calc_time is something like:

void calc_time(...) { if (isAbsolute) { calc_abs_time(...); } else { calc_rel_time(...); } }

I do not see a problem with this, only better readability?

/Robbin

Thanks, David -----

struct timespec now; int status = clockgettime(CLOCKMONOTONIC, &now); assertstatus(status == 0, status, "clockgettime"); calctime(abstime, timeout, isAbsolute, now.tvsec, now.tvnsec, NANOUNITS); } else { #else { #endif struct timeval now; int status = gettimeofday(&now, NULL); assert(status == 0, "gettimeofday"); calctime(abstime, timeout, isAbsolute, now.tvsec, now.tvusec, MICROUNITS); } #endif

Thanks for fixing this! /Robbin

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