On 2015/11/20 7:29, Sukadev Bhattiprolu wrote:
Wangnan (F) [wangn...@huawei.com] wrote:
|
|
| On 2015/11/19 7:14, Alexei Starovoitov wrote:
| >On Wed, Nov 18, 2015 at 05:50:39PM -0300, Arnaldo Carvalho de Melo wrote:
| >>Em Wed, Nov 18, 2015 at 11:26:04AM -0800, Sukadev Bhattiprolu escreveu:
| >>>>From 8f71d55dd3e27e6ca2138e3ed6dfeceb1c00a426 Mon Sep 17 00:00:00 2001
| >>>From: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
| >>>Date: Wed, 18 Nov 2015 19:06:08 -0500
| >>>Subject: [PATCH] perf test: Add bpf-output event
| >>>
| >>>The kernel has added support for 'PERF_COUNT_SW_BPF_OUTPUT' but that is
| >>>missing from the perf tool. Among other things, results in the 'roundtrip
| >>>evsel->name check' test case of 'perf test' failing on Powerpc.
| >>Next time can you please state if this is for this merge window or for
| >>the next?
| >>
| >>Will apply it for perf/core, for the next merge window.
| >wait a sec, I believe Wang has posted an RFC a month ago that adds support
| >for this properly instead of simply shutting up the error.
|
| Yes. Please have a look at
|
|
http://lkml.kernel.org/g/1446029705-199659-3-git-send-email-wangn...@huawei.com
|
| and patch 23/31 - 31/31 in
|
| http://lkml.kernel.org/g/1444826502-49291-1-git-send-email-wangn...@huawei.com
|
| We are working on a solution which truly utilizes bpf-output, including
| filling event array and extracting BPF output through perf data to CTF
| format. Now they are separated in multiple patchset, and I'd like to
| resend them to Arnaldo in this week.
Ok. It looked like there was development going on around BPF so I put
in the stubs to avoid false positives in the perf test. There is a BPF
filter test case that is also getting Skipped. Would this patchset address
that too?
Do you mean this?
$ ./perf test bpf
37: Test BPF filter :
37.1: Test basic BPF filtering : Skip
To make it pass you need to build BPF compiling environment first.
First of all you must be root:
$ ./perf test -v bpf
37: Test BPF filter :
37.1: Test basic BPF filtering :
--- start ---
test child forked, pid 19359
Only root can run BPF test
test child finished with -2
---- end ----
Test BPF filter subtest 0: Skip
Then it would tell you how to setup your LLVM environment:
$ sudo -s
# ./perf test -v bpf
37: Test BPF filter :
37.1: Test basic BPF filtering :
--- start ---
test child forked, pid 19463
ERROR: unable to find clang.
Hint: Try to install latest clang/llvm to support BPF. Check your $PATH
and 'clang-path' option in [llvm] section of ~/.perfconfig.
LLVM 3.7 or newer is required. Which can be found from
http://llvm.org
You may want to try git trunk:
git clone http://llvm.org/git/llvm.git
and
git clone http://llvm.org/git/clang.git
Or fetch the latest clang/llvm 3.7 from pre-built llvm
packages for
debian/ubuntu:
http://llvm.org/apt
If you are using old version of clang, change
'clang-bpf-cmd-template'
option in [llvm] section of ~/.perfconfig to:
"$CLANG_EXEC $CLANG_OPTIONS $KERNEL_INC_OPTIONS \
-working-directory $WORKING_DIR -c $CLANG_SOURCE \
-emit-llvm -o - | /path/to/llc -march=bpf -filetype=obj -o -"
(Replace /path/to/llc with path to your llc)
Failed to compile test case: 'Basic BPF llvm compiling test'
Unable to get BPF object, fix 'perf test LLVM' first
test child finished with -2
---- end ----
Test BPF filter subtest 0: Skip
Set your clang path to ~/.perfconfig
# cat ~/.perfconfig
[llvm]
clang-path = "/opt/llvm-3.7.0/x86_64-oe-linux-clang"
Then try 'perf test LLVM', fix all failure:
# ./perf test LLVM
35: Test LLVM searching and compiling :
35.1: Basic BPF llvm compiling test : Ok
35.2: Test kbuild searching : Ok
35.3: Compile source for BPF prologue generation test : Ok
After that you can try perf test BPF:
# ./perf test BPF
37: Test BPF filter :
37.1: Test basic BPF filtering : Ok
37.2: Test BPF prologue generation : Ok
Thank you.
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