Collecting build-ids for long running sessions may take a long time
because it needs to traverse the whole just collected perf.data stream
of events, marking the DSOs that had hits and then looking for the
.note.gnu.build-id ELF section.

For things like the 'trace' tool that records and right away consumes
the data on systems where its unlikely that the DSOs being monitored
will change while 'trace' runs, it is desirable to remove build id
collection, so add a -B/--no-buildid option to perf record to allow such
use case.

Longer term we'll avoid all this if we, at DSO load time, in the kernel,
take advantage of this slow code path to collect the build-id and stash
it somewhere, so that we can insert it in the PERF_RECORD_MMAP event.
Reported-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

We need to refactor code to be explicitely shared by the kernel and at
least the tools/ userspace programs, so, till we do that, copy the bare
minimum bitmap/bitops code needed by tools/perf.
Reported-by: N"H. Peter Anvin" <hpa@zytor.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Currently, perf fails to compile on powerpc with this error:

     CC util/header.o
 In file included from util/../perf.h:17,
                  from util/header.c:9:
 util/../../../arch/powerpc/include/asm/unistd.h:360:27: error:
 linux/linkage.h: No such file or directory make: ***
 [util/header.o] Error 1

The reason is that we still have a #define __KERNEL__ in effect
at the point where <asm/unistd.h> gets included, which means we
get extra stuff that we don't need or want.

This fixes the problem by undefining __KERNEL__ once we have
included the file for which we need __KERNEL__ defined.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <19211.24287.453183.78836@cargo.ozlabs.ibm.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Use the kernel bitmap library for internal perf tools uses.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <1255792354-11304-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>