[PATCH 2/5] tools lib perf: Add dependency test to install_headers

[Ian Rogers]

Compute the headers to be installed from their source headers and make
each have its own build target to install it. Using dependencies
avoids headers being reinstalled and getting a new timestamp which
then causes files that depend on the header to be rebuilt.

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
 tools/lib/perf/Makefile | 43 +++++++++++++++++++++--------------------
 1 file changed, 22 insertions(+), 21 deletions(-)

diff --git a/tools/lib/perf/Makefile b/tools/lib/perf/Makefile
index a90fb8c6bed4..30b7f91e7147 100644
--- a/tools/lib/perf/Makefile
+++ b/tools/lib/perf/Makefile
@@ -176,10 +176,10 @@ define do_install_mkdir
 endef
 
 define do_install
-	if [ ! -d '$(DESTDIR_SQ)$2' ]; then             \
-		$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$2'; \
-	fi;                                             \
-	$(INSTALL) $1 $(if $3,-m $3,) '$(DESTDIR_SQ)$2'
+	if [ ! -d '$2' ]; then             \
+		$(INSTALL) -d -m 755 '$2'; \
+	fi;                                \
+	$(INSTALL) $1 $(if $3,-m $3,) '$2'
 endef
 
 install_lib: libs
@@ -187,23 +187,24 @@ install_lib: libs
 		$(call do_install_mkdir,$(libdir_SQ)); \
 		cp -fpR $(LIBPERF_ALL) $(DESTDIR)$(libdir_SQ)
 
-install_headers:
-	$(call QUIET_INSTALL, libperf_headers) \
-		$(call do_install,include/perf/bpf_perf.h,$(prefix)/include/perf,644); \
-		$(call do_install,include/perf/core.h,$(prefix)/include/perf,644); \
-		$(call do_install,include/perf/cpumap.h,$(prefix)/include/perf,644); \
-		$(call do_install,include/perf/threadmap.h,$(prefix)/include/perf,644); \
-		$(call do_install,include/perf/evlist.h,$(prefix)/include/perf,644); \
-		$(call do_install,include/perf/evsel.h,$(prefix)/include/perf,644); \
-		$(call do_install,include/perf/event.h,$(prefix)/include/perf,644); \
-		$(call do_install,include/perf/mmap.h,$(prefix)/include/perf,644); \
-		$(call do_install,include/internal/cpumap.h,$(prefix)/include/internal,644); \
-		$(call do_install,include/internal/evlist.h,$(prefix)/include/internal,644); \
-		$(call do_install,include/internal/evsel.h,$(prefix)/include/internal,644); \
-		$(call do_install,include/internal/lib.h,$(prefix)/include/internal,644); \
-		$(call do_install,include/internal/mmap.h,$(prefix)/include/internal,644); \
-		$(call do_install,include/internal/threadmap.h,$(prefix)/include/internal,644); \
-		$(call do_install,include/internal/xyarray.h,$(prefix)/include/internal,644);
+HDRS := bpf_perf.h core.h cpumap.h threadmap.h evlist.h evsel.h event.h mmap.h
+INTERNAL_HDRS := cpumap.h evlist.h evsel.h lib.h mmap.h threadmap.h xyarray.h
+
+INSTALL_HDRS_PFX := $(DESTDIR)$(prefix)/include/perf
+INSTALL_HDRS := $(addprefix $(INSTALL_HDRS_PFX)/, $(HDRS))
+INSTALL_INTERNAL_HDRS_PFX := $(DESTDIR)$(prefix)/include/internal
+INSTALL_INTERNAL_HDRS := $(addprefix $(INSTALL_INTERNAL_HDRS_PFX)/, $(INTERNAL_HDRS))
+
+$(INSTALL_HDRS): $(INSTALL_HDRS_PFX)/%.h: include/perf/%.h
+	$(call QUIET_INSTALL, $@) \
+		$(call do_install,$<,$(INSTALL_HDRS_PFX)/,644)
+
+$(INSTALL_INTERNAL_HDRS): $(INSTALL_INTERNAL_HDRS_PFX)/%.h: include/internal/%.h
+	$(call QUIET_INSTALL, $@) \
+		$(call do_install,$<,$(INSTALL_INTERNAL_HDRS_PFX)/,644)
+
+install_headers: $(INSTALL_HDRS) $(INSTALL_INTERNAL_HDRS)
+	$(call QUIET_INSTALL, libperf_headers)
 
 install_pkgconfig: $(LIBPERF_PC)
 	$(call QUIET_INSTALL, $(LIBPERF_PC)) \
-- 
2.39.0.rc0.267.gcb52ba06e7-goog