From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnaldo Carvalho de Melo Subject: [PATCH 21/23] perf kvm: Clarify the 'perf kvm' -i and -o command line options Date: Tue, 3 Dec 2019 10:56:04 -0300 Message-ID: <20191203135606.24902-22-acme@kernel.org> References: <20191203135606.24902-1-acme@kernel.org> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20191203135606.24902-1-acme@kernel.org> Sender: linux-kernel-owner@vger.kernel.org To: Ingo Molnar , Thomas Gleixner Cc: Jiri Olsa , Namhyung Kim , Clark Williams , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Arnaldo Carvalho de Melo , Adrian Hunter , Steve Dickson , William Cohen List-Id: linux-perf-users.vger.kernel.org From: Arnaldo Carvalho de Melo The 'perf kvm' subcommand has options that it in turn passes to other perf subcommands such as 'report' and 'record', particularly -i and -o end up setting the same variable that will then be used for 'record's -o and report '-i', which ends up being confusing, leading some to think that both -i and -o can be used with 'report'. Improve the man page to state that -i is used with the post-processing subcommands while -o is used just with 'record' and that to save the output of 'report' one should simply redirect its output to a file. Noticed while reading the https://www.linux-kvm.org/page/Perf_events page. Cc: Adrian Hunter Cc: Jiri Olsa Cc: Namhyung Kim Cc: Steve Dickson Cc: William Cohen Link: https://lkml.kernel.org/n/tip-tclbttvmgtm525fvmh85f7d9@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/Documentation/perf-kvm.txt | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/tools/perf/Documentation/perf-kvm.txt b/tools/perf/Documentation/perf-kvm.txt index 6a5bb2b17039..cf95baef7b61 100644 --- a/tools/perf/Documentation/perf-kvm.txt +++ b/tools/perf/Documentation/perf-kvm.txt @@ -68,10 +68,11 @@ OPTIONS ------- -i:: --input=:: - Input file name. + Input file name, for the 'report', 'diff' and 'buildid-list' subcommands. -o:: --output=:: - Output file name. + Output file name, for the 'record' subcommand. Doesn't work with 'report', + just redirect the output to a file when using 'report'. --host:: Collect host side performance profile. --guest:: -- 2.21.0