[tip: perf/core] perf doc: Set man page date to last git commit

[tip-bot2 for Ian Rogers]

The following commit has been merged into the perf/core branch of tip:

Commit-ID:     0c2d041232411c8124136c9497c0e352dcf18baa
Gitweb:        https://git.kernel.org/tip/0c2d041232411c8124136c9497c0e352dcf18baa
Author:        Ian Rogers <irogers@xxxxxxxxxx>
AuthorDate:    Tue, 10 Mar 2020 22:21:10 -07:00
Committer:     Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitterDate: Wed, 11 Mar 2020 10:48:44 -03:00

perf doc: Set man page date to last git commit

Currently the man page dates reflect the date the man pages were built.
This patch adjusts the date so that the date is when then man page
last had a commit against it. The date is generated using 'git log'.

Committer testing:

  $ git log -1 --pretty="format:%cd" --date=short tools/perf/Documentation/perf-top.txt
  2020-01-14

Before:

  rm -rf /tmp/build/perf
  mkdir -p /tmp/build/perf
  make -C tools/perf O=/tmp/build/perf/ install
  $ date
  Wed 11 Mar 2020 10:21:19 AM -03
  $ man perf-top | tail -1
  perf                    03/11/2020           PERF-TOP(1)
  $

After:

  rm -rf /tmp/build/perf
  mkdir -p /tmp/build/perf
  make -C tools/perf O=/tmp/build/perf/ install
  $ date
  $ date
  Wed 11 Mar 2020 10:24:06 AM -03
  $ man perf-top | tail -1
  perf                    2020-01-14           PERF-TOP(1)
  $

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
Tested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Masanari Iida <standby24x7@xxxxxxxxx>
Cc: Mukesh Ojha <mojha@xxxxxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: http://lore.kernel.org/lkml/20200311052110.23132-1-irogers@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
 tools/perf/Documentation/Makefile | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/tools/perf/Documentation/Makefile b/tools/perf/Documentation/Makefile
index adc5a7e..31824d5 100644
--- a/tools/perf/Documentation/Makefile
+++ b/tools/perf/Documentation/Makefile
@@ -295,7 +295,10 @@ $(OUTPUT)%.1 $(OUTPUT)%.5 $(OUTPUT)%.7 : $(OUTPUT)%.xml
 $(OUTPUT)%.xml : %.txt
 	$(QUIET_ASCIIDOC)$(RM) $@+ $@ && \
 	$(ASCIIDOC) -b docbook -d manpage \
-		$(ASCIIDOC_EXTRA) -aperf_version=$(PERF_VERSION) -o $@+ $< && \
+		$(ASCIIDOC_EXTRA) -aperf_version=$(PERF_VERSION) \
+		-aperf_date=$(shell git log -1 --pretty="format:%cd" \
+				--date=short $<) \
+		-o $@+ $< && \
 	mv $@+ $@
 
 XSLT = docbook.xsl