Messages in this thread | | | Date | Mon, 11 Nov 2013 17:24:02 +0100 | From | Peter Zijlstra <> | Subject | Re: [tip:perf/core] tools/perf: Add required memory barriers |
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On Thu, Nov 07, 2013 at 09:21:22AM +0100, Ingo Molnar wrote: > > * Peter Zijlstra <peterz@infradead.org> wrote: > > > > Requiring the user of a kernel interface to have a deep knowledge of > > > optimizing compilers, barriers, and CPU memory models is just asking > > > for trouble. > > > > It shouldn't be all that hard to put this in a (lgpl) library others can > > link to -- that way you can build it once (using GCC). > > I'd suggest to expose it via a new perf syscall, using vsyscall methods to > not have to enter the kernel for the pure user-space bits. It should also > have a real usecase in tools/perf/ so that it's constantly tested, with > matching 'perf test' entries, etc.
Oh man, I've never poked at the entire vsyscall stuff before; let alone done it for ARM, ARM64, PPC64 etc..
Keeping it in userspace like we have is so much easier.
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