Re: [PATCH] ftrace: Provide trace clock monotonic raw

2015-05-08 Thread Drew Richardson
On Fri, May 08, 2015 at 03:09:03PM +0100, Steven Rostedt wrote: > On Tue, 5 May 2015 07:54:46 -0700 > Drew Richardson wrote: > > > CLOCK_MONOTONIC_RAW will advance more constantly than CLOCK_MONOTONIC. > > > > Imagine someone is trying to optimize a particular program to reduce > > instructions

Re: [PATCH] ftrace: Provide trace clock monotonic raw

2015-05-08 Thread Steven Rostedt
On Tue, 5 May 2015 07:54:46 -0700 Drew Richardson wrote: > CLOCK_MONOTONIC_RAW will advance more constantly than CLOCK_MONOTONIC. > > Imagine someone is trying to optimize a particular program to reduce > instructions executed for a given workload while minimizing the effect > on runtime. Also

Re: [PATCH] ftrace: Provide trace clock monotonic raw

2015-05-07 Thread Mathieu Desnoyers
- Original Message - > On Tue, 5 May 2015 07:54:46 -0700 > Drew Richardson wrote: > > > CLOCK_MONOTONIC_RAW will advance more constantly than CLOCK_MONOTONIC. > > > > Imagine someone is trying to optimize a particular program to reduce > > instructions executed for a given workload while

Re: [PATCH] ftrace: Provide trace clock monotonic raw

2015-05-07 Thread Steven Rostedt
On Tue, 5 May 2015 07:54:46 -0700 Drew Richardson wrote: > CLOCK_MONOTONIC_RAW will advance more constantly than CLOCK_MONOTONIC. > > Imagine someone is trying to optimize a particular program to reduce > instructions executed for a given workload while minimizing the effect > on runtime. Also s

Re: [PATCH] ftrace: Provide trace clock monotonic raw

2015-05-05 Thread Drew Richardson
On Mon, May 04, 2015 at 09:57:48PM +0100, Peter Zijlstra wrote: > On Mon, May 04, 2015 at 01:05:19PM -0700, Drew Richardson wrote: > > I'm collecting and merging data from perf, with Android Atrace data > > (writes to /sys/kernel/debug/tracing/trace_marker) which ends up in > > the ftrace stream an

Re: [PATCH] ftrace: Provide trace clock monotonic raw

2015-05-04 Thread Peter Zijlstra
On Mon, May 04, 2015 at 01:05:19PM -0700, Drew Richardson wrote: > I'm collecting and merging data from perf, with Android Atrace data > (writes to /sys/kernel/debug/tracing/trace_marker) which ends up in > the ftrace stream and other measurements collected from > userspace. Currently the only cloc

Re: [PATCH] ftrace: Provide trace clock monotonic raw

2015-05-04 Thread John Stultz
On Mon, May 4, 2015 at 1:05 PM, Drew Richardson wrote: > On Mon, May 04, 2015 at 04:10:05PM +0100, Mathieu Desnoyers wrote: >> - Original Message - >> > Expose the NMI safe accessor to the monotonic raw clock to the >> > tracer. The mono clock was added with commit >> > 1b3e5c0936046e7e023

Re: [PATCH] ftrace: Provide trace clock monotonic raw

2015-05-04 Thread Drew Richardson
On Mon, May 04, 2015 at 04:10:05PM +0100, Mathieu Desnoyers wrote: > - Original Message - > > Expose the NMI safe accessor to the monotonic raw clock to the > > tracer. The mono clock was added with commit > > 1b3e5c0936046e7e023149ddc8946d21c2ea20eb. Although the monotonic raw > > clock ca

Re: [PATCH] ftrace: Provide trace clock monotonic raw

2015-05-04 Thread Mathieu Desnoyers
- Original Message - > Expose the NMI safe accessor to the monotonic raw clock to the > tracer. The mono clock was added with commit > 1b3e5c0936046e7e023149ddc8946d21c2ea20eb. Although the monotonic raw > clock cannot be used to compare time between different machines, it is > not perterbe

[PATCH] ftrace: Provide trace clock monotonic raw

2015-05-04 Thread Drew Richardson
Expose the NMI safe accessor to the monotonic raw clock to the tracer. The mono clock was added with commit 1b3e5c0936046e7e023149ddc8946d21c2ea20eb. Although the monotonic raw clock cannot be used to compare time between different machines, it is not perterbed by ntp. Signed-off-by: Drew Richards