That does all the initialization boilerplate, opening the file,
reading the header, checking if it is valid, etc.

And that will as well have the threads list, kmap (now) global
variable, etc, so that we can handle two (or more) perf.data files
describing sessions to compare.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1260573842-19720-1-git-send-email-acme@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1260129790-11520-1-git-send-email-acme@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Porcelain can ignore it, humans can make more sense of it.
Suggested-by: NFrederic Weisbecker <fweisbec@gmail.com>
Suggested-by: NIngo Molnar <mingo@elte.hu>
Suggested-by: NPeter Zijlstra <peterz@infradead.org>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <1258415125-15019-2-git-send-email-acme@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

With this we can list the buildids in a perf.data file so that
we can pipe them to other, distro specific tools that from the
buildids can figure out separate packages (foo-debuginfo) where
we can find the matching symtabs so that perf report can do its
job.

E.g:

[acme@doppio linux-2.6-tip]$ perf buildid-list | head -5
8e08b117e5458ad3f85da16d42d0fc5cd21c5869
520c2387a587cc5acfcf881e27dba1caaeab4b1f
ec8dd400904ddfcac8b1c343263a790f977159dc
7caedbca5a6d8ab39a7fe44bd28c07d3e14a3f3f
379bb828fd08859dbea73279f04abefabc95a6a3
[acme@doppio linux-2.6-tip]$ perf buildid-list -v | head -5
8e08b117e5458ad3f85da16d42d0fc5cd21c5869 /sbin/init
520c2387a587cc5acfcf881e27dba1caaeab4b1f /lib64/ld-2.10.1.so
ec8dd400904ddfcac8b1c343263a790f977159dc /lib64/libc-2.10.1.so
7caedbca5a6d8ab39a7fe44bd28c07d3e14a3f3f /sbin/udevd
379bb828fd08859dbea73279f04abefabc95a6a3 /lib64/libdl-2.10.1.so
[acme@doppio linux-2.6-tip]$
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <1258396365-29217-5-git-send-email-acme@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>