[PATCH] perf doc: Set man page date to last git commit

[Ian Rogers]

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'.

Signed-off-by: Ian Rogers <irogers@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 adc5a7e44b98..31824d5269cc 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
-- 
2.25.1.481.gfbce0eb801-goog