Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757864Ab3JNUDQ (ORCPT ); Mon, 14 Oct 2013 16:03:16 -0400 Received: from merlin.infradead.org ([205.233.59.134]:38543 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756708Ab3JNUCv (ORCPT ); Mon, 14 Oct 2013 16:02:51 -0400 From: Arnaldo Carvalho de Melo To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, Arnaldo Carvalho de Melo , Peter Zijlstra , Namhyung Kim , David Ahern , Jiri Olsa Subject: [PATCH 034/161] tools/perf/build: Speed up the final link Date: Mon, 14 Oct 2013 17:00:23 -0300 Message-Id: <1381780950-25642-35-git-send-email-acme@infradead.org> X-Mailer: git-send-email 1.8.1.4 In-Reply-To: <1381780950-25642-1-git-send-email-acme@infradead.org> References: <1381780950-25642-1-git-send-email-acme@infradead.org> X-SRS-Rewrite: SMTP reverse-path rewritten from by merlin.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2711 Lines: 92 From: Ingo Molnar libtraceevent.a and liblk.a rules have always-missed dependencies, which causes python.so to be relinked at every build attempt - even if none of the affected code changes. This slows down re-builds unnecessarily, by adding more than a second to the build time: comet:~/tip/tools/perf> time make ... SUBDIR /fast/mingo/tip/tools/lib/lk/ make[1]: `liblk.a' is up to date. SUBDIR /fast/mingo/tip/tools/lib/traceevent/ LINK perf GEN python/perf.so real 0m1.701s user 0m1.338s sys 0m0.301s Add the (trivial) dependencies to not force a re-link. This speeds up an empty re-build enormously: comet:~/tip/tools/perf> time make ... real 0m0.207s user 0m0.134s sys 0m0.028s [ This adds some coupling between the build dependencies of libtraceevent and liblk - but until those stay relatively simple this should not be an issue. ] Cc: Arnaldo Carvalho de Melo Cc: Peter Zijlstra Cc: Namhyung Kim Cc: David Ahern Cc: Jiri Olsa Link: http://lkml.kernel.org/n/tip-wvmlrurufuk6mo1ovtNigguT@git.kernel.org Signed-off-by: Ingo Molnar --- tools/perf/Makefile | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/tools/perf/Makefile b/tools/perf/Makefile index 6b5452a120af..df76198d45d4 100644 --- a/tools/perf/Makefile +++ b/tools/perf/Makefile @@ -669,15 +669,19 @@ $(LIB_FILE): $(LIB_OBJS) $(QUIET_AR)$(RM) $@ && $(AR) rcs $@ $(LIB_OBJS) # libtraceevent.a -$(LIBTRACEEVENT): +TE_SOURCES = $(wildcard $(TRACE_EVENT_DIR)*.[ch]) + +$(LIBTRACEEVENT): $(TE_SOURCES) $(QUIET_SUBDIR0)$(TRACE_EVENT_DIR) $(QUIET_SUBDIR1) O=$(OUTPUT) libtraceevent.a $(LIBTRACEEVENT)-clean: $(QUIET_SUBDIR0)$(TRACE_EVENT_DIR) $(QUIET_SUBDIR1) O=$(OUTPUT) clean +LIBLK_SOURCES = $(wildcard $(LK_PATH)*.[ch]) + # if subdir is set, we've been called from above so target has been built # already -$(LIBLK): +$(LIBLK): $(LIBLK_SOURCES) ifeq ($(subdir),) $(QUIET_SUBDIR0)$(LK_DIR) $(QUIET_SUBDIR1) O=$(OUTPUT) liblk.a endif @@ -825,6 +829,6 @@ else GIT-HEAD-PHONY = endif -.PHONY: all install clean strip $(LIBTRACEEVENT) $(LIBLK) +.PHONY: all install clean strip .PHONY: shell_compatibility_test please_set_SHELL_PATH_to_a_more_modern_shell .PHONY: $(GIT-HEAD-PHONY) TAGS tags cscope .FORCE-PERF-CFLAGS -- 1.8.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/