perf: multiple mmap of fd behavior on x86/ARM

From	Vince Weaver <vincent.weaver@maine.edu>
Newsgroups	linux.kernel
Subject	perf: multiple mmap of fd behavior on x86/ARM
Date	2017-08-10 20:50 +0200
Message-ID	<ud0GS-17N-15@gated-at.bofh.it> (permalink)
Organization	linux.* mail to news gateway

Show all headers | View raw

So I was working on my perf_event_tests on ARM/ARM64 (the end goal was to 
get ARM64 rdpmc support working, but apparently those patches never made 
it upstream?)

anyway one test was failing due to an x86/arm difference, which is 
possibly only tangentially perf related.

On x86 you can mmap() a perf_event_open() file descriptor multiple times 
and it works.

On ARM/ARM64 you can only mmap() it once, any other attempts fail.

Is this expected behavior?

You can run the
	tests/record_sample/mmap_multiple
test in the current git of my perf_event_tests testsuite for a testcase.

Vince

Back to linux.kernel | Previous | Next — Next in thread | Find similar | Unroll thread

Thread

perf: multiple mmap of fd behavior on x86/ARM Vince Weaver <vincent.weaver@maine.edu> - 2017-08-10 20:50 +0200
  Re: perf: multiple mmap of fd behavior on x86/ARM Mark Rutland <mark.rutland@arm.com> - 2017-08-11 12:10 +0200
    Re: perf: multiple mmap of fd behavior on x86/ARM Peter Zijlstra <peterz@infradead.org> - 2017-08-11 13:00 +0200
      Re: perf: multiple mmap of fd behavior on x86/ARM Mark Rutland <mark.rutland@arm.com> - 2017-08-11 13:10 +0200
        Re: perf: multiple mmap of fd behavior on x86/ARM Peter Zijlstra <peterz@infradead.org> - 2017-08-11 17:00 +0200
    Re: perf: multiple mmap of fd behavior on x86/ARM Vince Weaver <vincent.weaver@maine.edu> - 2017-08-11 17:30 +0200
      Re: perf: multiple mmap of fd behavior on x86/ARM Mark Rutland <mark.rutland@arm.com> - 2017-08-11 18:30 +0200
        Re: perf: multiple mmap of fd behavior on x86/ARM Vince Weaver <vincent.weaver@maine.edu> - 2017-08-11 19:00 +0200
          Re: perf: multiple mmap of fd behavior on x86/ARM Mark Rutland <mark.rutland@arm.com> - 2017-08-11 19:20 +0200
            Re: perf: multiple mmap of fd behavior on x86/ARM Vince Weaver <vincent.weaver@maine.edu> - 2017-08-11 21:10 +0200

csiph-web