Messages in this thread | | | Date | Thu, 5 Sep 2013 13:45:09 +0100 | From | Will Deacon <> | Subject | Re: [PATCH 3/3] perf: parse the .debug_frame section in case .eh_frame is not present |
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Hi Jean,
[adding Michael, since I know he was interested in this]
On Wed, Sep 04, 2013 at 07:04:14PM +0100, Jean Pihet wrote: > On ARM the debug info is not present in the .eh_frame sections but > instead in .debug_frame. > Use libunwind to load and parse the debug info.
How have you tested this? Regardless of whether or not I apply this patch, I get the same (broken/truncated) callchains for userspace in perf report.
E.g. the following stupid program (built with -O0 -g):
--->8
void bar(void) { int i; for (i = 0; i < 1000000; ++i) asm volatile("nop" ::: "memory"); }
void foo(void) { bar(); }
int main(void) { foo(); return 0; }
8<---
Gives me an incomplete callchain:
# Overhead Command Shared Object Symbol # ........ ........ ................. ............................... # 0.00% unwindme unwindme [.] bar | --- bar
This is the same with or without your patch.
Will
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