From mboxrd@z Thu Jan  1 00:00:00 1970
From: Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>
Subject: Re: [RFC] perf top and deleted binaries
Date: Mon, 9 May 2011 17:58:49 -0300
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To: Arun Sharma <asharma@fb.com>
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Em Mon, May 09, 2011 at 11:28:23AM -0700, Arun Sharma escreveu:
> 
> For long running binaries which may have been replaced or deleted, today 
> perf top spits out a warning and doesn't show anything. For eg:
> 
> test.c:
> 
> main()
> {
> 	while(1);
> }
> 
> gcc -O2 test.c -o test
> ./test &
> gcc -O2 test.c -o test	# overwrite the binary
> perf top -p <pid>
> 
> shows nothing. It could instead show:
> 
> 100% <unresolved>	test
> 
> like perf record/report would show for the same test case. Comments?

Agreed :-)

When/if we get build-id as first class citizen, stashing it in some
kernel data structure at DSO load time, we'll be able to use it for
content based DSO lookup in the cache.

- Arnaldo