Building perf is pretty slow on trees that have a lot of commits
relative to the nearest Git tag. This slowness manifests itself during
version string generation:
$ perf stat --null --repeat 3 --sync --pre "rm -f PERF-VERSION-FILE" util/PERF-VERSION-GEN
PERF_VERSION = 3.7.rc3.1458.g5399b3b
PERF_VERSION = 3.7.rc3.1458.g5399b3b
PERF_VERSION = 3.7.rc3.1458.g5399b3b
Performance counter stats for 'util/PERF-VERSION-GEN' (3 runs):
2.857503976 seconds time elapsed ( +- 0.22% )
The build can be even slower than that, when one over NFS volumes.
The reason for the slowness is that util/PERF-VERSION-GEN uses "git
describe" to generate the string, which has to count the "number of
commits distance" from the nearest tag - the ".1458." count in the
output above. For that Git had to extract and decompress 1458 Git
objects, which takes time and bandwidth.
But this "number of commits" value is mostly irrelevant in practice. We
either want to know an approximate tag name, or we want to know the
precise sha1.
So this patch simplifies the version string to:
PERF_VERSION = 3.7.rc3.g5399b3b.dirty
which speeds up the version string generation script by an order of
magnitude:
$ perf stat --null --repeat 3 --sync --pre "rm -f PERF-VERSION-FILE" util/PERF-VERSION-GEN
PERF_VERSION = 3.7.rc3.g5399b3b.dirty
PERF_VERSION = 3.7.rc3.g5399b3b.dirty
PERF_VERSION = 3.7.rc3.g5399b3b.dirty
Performance counter stats for 'util/PERF-VERSION-GEN' (3 runs):
0.307633559 seconds time elapsed ( +- 0.84% )
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Vagin <avagin@openvz.org>
Cc: Borislav Petkov <bp@amd64.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20121030084600.GB8245@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When generating the perf version from the kernel version using 'make
kernelver' it is necessary to clear out any MAKEFLAGS otherwise they may
trigger additional output which pollute the contents.
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Some versions of grep don't treat '\s' properly. When building perf on such
systems and using a kernel tarball the perf version is unable to be determined
from the main kernel Makefile and the user is left with a version of '..'.
Replacing the use of '\s' with '[[:space:]]', which should work in all grep
versions, gives a usable version number.
Reported-by: Tapan Dhimant <tdhimant@akamai.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Tapan Dhimant <tdhimant@akamai.com>
Cc: linux-kernel@vger.kernel.org
Cc: stable@kernel.org
LKML-Reference: <1300241800-30281-1-git-send-email-johunt@akamai.com>
Signed-off-by: Josh Hunt <johunt@akamai.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This gets rid of the default version fallback for Perf and
changes it so that it returns the version of the kernel from
it's Makefile (if sources were not from git, ie. if it was
downloaded from a tarball)
Signed-off-by: Thavidu Ranatunga <tharan@au1.ibm.com>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1278316815-6099-2-git-send-email-tharan@au1.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Changes the Perf --version string such that it shows the kernel
version as suggested by Ingo as follows:
That way the perf that comes with v2.6.34 will be:
perf version v2.6.34
while interim versions will have the version of the interim
kernel - for example:
perf version v2.6.35-rc4-70-g39ef13a
This functionality was already in the perf version generator
file except that it was looking for a .git in the perf directory
instead of the kernel directory.
Signed-off-by: Thavidu Ranatunga <tharan@au1.ibm.com>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1278316815-6099-1-git-send-email-tharan@au1.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Avoiding polluting the source tree with build files.
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
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>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We released the first version of perf with 0.0.1 in v2.6.31,
time to double our version number to 0.0.2 ;-)
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Several people have suggested that 'perf' has become a full-fledged
tool that should be moved out of Documentation/. Move it to the
(new) tools/ directory.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-06-06 20:33:43 +02:00
Renamed from Documentation/perf_counter/util/PERF-VERSION-GEN (Browse further)