* Re: [tip:timers/urgent] ktime: Get rid of the union [not found] <tip-64dac5c9e0f5a933e4520f0cb689b7b143925207@git.kernel.org> @ 2017-01-03 10:36 ` Peter Zijlstra 2017-01-04 8:54 ` Thomas Gleixner 0 siblings, 1 reply; 4+ messages in thread From: Peter Zijlstra @ 2017-01-03 10:36 UTC (permalink / raw) To: linux-kernel, mingo, tglx, hpa; +Cc: linux-tip-commits On Sun, Dec 25, 2016 at 05:26:33AM -0800, tip-bot for Thomas Gleixner wrote: > Commit-ID: 64dac5c9e0f5a933e4520f0cb689b7b143925207 > Gitweb: http://git.kernel.org/tip/64dac5c9e0f5a933e4520f0cb689b7b143925207 > Author: Thomas Gleixner <tglx@linutronix.de> > AuthorDate: Sun, 25 Dec 2016 11:38:40 +0100 > Committer: Thomas Gleixner <tglx@linutronix.de> > CommitDate: Sun, 25 Dec 2016 13:11:50 +0100 > > ktime: Get rid of the union > > ktime is a union because the initial implementation stored the time in > scalar nanoseconds on 64 bit machine and in a endianess optimized timespec > variant for 32bit machines. The Y2038 cleanup removed the timespec variant > and switched everything to scalar nanoseconds. The union remained, but > become completely pointless. > > Get rid of the union and just keep ktime_t as simple typedef of type s64. All good stuff. One question that remains is why keep the type while removing the cycles_t type? ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [tip:timers/urgent] ktime: Get rid of the union 2017-01-03 10:36 ` [tip:timers/urgent] ktime: Get rid of the union Peter Zijlstra @ 2017-01-04 8:54 ` Thomas Gleixner 2017-01-04 9:39 ` Peter Zijlstra 0 siblings, 1 reply; 4+ messages in thread From: Thomas Gleixner @ 2017-01-04 8:54 UTC (permalink / raw) To: Peter Zijlstra; +Cc: linux-kernel, mingo, hpa, linux-tip-commits On Tue, 3 Jan 2017, Peter Zijlstra wrote: > On Sun, Dec 25, 2016 at 05:26:33AM -0800, tip-bot for Thomas Gleixner wrote: > > Commit-ID: 64dac5c9e0f5a933e4520f0cb689b7b143925207 > > Gitweb: http://git.kernel.org/tip/64dac5c9e0f5a933e4520f0cb689b7b143925207 > > Author: Thomas Gleixner <tglx@linutronix.de> > > AuthorDate: Sun, 25 Dec 2016 11:38:40 +0100 > > Committer: Thomas Gleixner <tglx@linutronix.de> > > CommitDate: Sun, 25 Dec 2016 13:11:50 +0100 > > > > ktime: Get rid of the union > > > > ktime is a union because the initial implementation stored the time in > > scalar nanoseconds on 64 bit machine and in a endianess optimized timespec > > variant for 32bit machines. The Y2038 cleanup removed the timespec variant > > and switched everything to scalar nanoseconds. The union remained, but > > become completely pointless. > > > > Get rid of the union and just keep ktime_t as simple typedef of type s64. > > All good stuff. One question that remains is why keep the type while > removing the cycles_t type? That would have been a massive surgery which I was not able to pull off on top of the other changes. Thanks, tglx ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [tip:timers/urgent] ktime: Get rid of the union 2017-01-04 8:54 ` Thomas Gleixner @ 2017-01-04 9:39 ` Peter Zijlstra 2017-01-04 13:47 ` Frederic Weisbecker 0 siblings, 1 reply; 4+ messages in thread From: Peter Zijlstra @ 2017-01-04 9:39 UTC (permalink / raw) To: Thomas Gleixner; +Cc: linux-kernel, mingo, hpa, linux-tip-commits On Wed, Jan 04, 2017 at 09:54:12AM +0100, Thomas Gleixner wrote: > On Tue, 3 Jan 2017, Peter Zijlstra wrote: > > > Get rid of the union and just keep ktime_t as simple typedef of type s64. > > > > All good stuff. One question that remains is why keep the type while > > removing the cycles_t type? > > That would have been a massive surgery which I was not able to pull off on > top of the other changes. And the reason ktime needs be s64 is because 0 is at boot, and we need to represent time before boot, right? Might want to stick that in a comment somewhere near that typedef, so I don't keep asking this ;-) ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [tip:timers/urgent] ktime: Get rid of the union 2017-01-04 9:39 ` Peter Zijlstra @ 2017-01-04 13:47 ` Frederic Weisbecker 0 siblings, 0 replies; 4+ messages in thread From: Frederic Weisbecker @ 2017-01-04 13:47 UTC (permalink / raw) To: Peter Zijlstra Cc: Thomas Gleixner, LKML, Ingo Molnar, H. Peter Anvin, linux-tip-commits 2017-01-04 10:39 GMT+01:00 Peter Zijlstra <peterz@infradead.org>: > On Wed, Jan 04, 2017 at 09:54:12AM +0100, Thomas Gleixner wrote: >> On Tue, 3 Jan 2017, Peter Zijlstra wrote: > >> > > Get rid of the union and just keep ktime_t as simple typedef of type s64. >> > >> > All good stuff. One question that remains is why keep the type while >> > removing the cycles_t type? >> >> That would have been a massive surgery which I was not able to pull off on >> top of the other changes. > > And the reason ktime needs be s64 is because 0 is at boot, and we need > to represent time before boot, right? Might want to stick that in a > comment somewhere near that typedef, so I don't keep asking this ;-) Aaah, that confused me as well :-) ^ permalink raw reply [flat|nested] 4+ messages in thread
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[not found] <tip-64dac5c9e0f5a933e4520f0cb689b7b143925207@git.kernel.org>
2017-01-03 10:36 ` [tip:timers/urgent] ktime: Get rid of the union Peter Zijlstra
2017-01-04 8:54 ` Thomas Gleixner
2017-01-04 9:39 ` Peter Zijlstra
2017-01-04 13:47 ` Frederic Weisbecker
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