Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265914AbTIETYB (ORCPT ); Fri, 5 Sep 2003 15:24:01 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265912AbTIETXi (ORCPT ); Fri, 5 Sep 2003 15:23:38 -0400 Received: from pasmtp.tele.dk ([193.162.159.95]:27912 "EHLO pasmtp.tele.dk") by vger.kernel.org with ESMTP id S265906AbTIETWC (ORCPT ); Fri, 5 Sep 2003 15:22:02 -0400 Date: Fri, 5 Sep 2003 21:21:41 +0200 From: Sam Ravnborg To: John Cherry , "Justin T. Gibbs" Cc: "Justin T. Gibbs" , trivial@rustcorp.com.au, "linux-kernel@vger.kernel.org" Subject: Re: [TRIVIAL][PATCH] fix parallel builds for aic7xxx] Message-ID: <20030905192141.GA9277@mars.ravnborg.org> Mail-Followup-To: John Cherry , "Justin T. Gibbs" , trivial@rustcorp.com.au, "linux-kernel@vger.kernel.org" References: <1062698342.9322.73.camel@cherrytest.pdx.osdl.net> <59600000.1062714135@aslan.btc.adaptec.com> <1062779785.12723.41.camel@cherrytest.pdx.osdl.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1062779785.12723.41.camel@cherrytest.pdx.osdl.net> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3702 Lines: 112 Hi Justin, John. I agree with Justin that the patch for aic7xxx/Makefile looks a bit suspisious. I have modifed it to use a phony target as serialisation point. In this way it is more obvious what is actually happening. The patch for aicasm/Makefile looked OK - included here as well to make the patch complete. I have tested this patch on UP only, with make -j4. Before it broke in aicasm, now it succeeds. Justin, does this look OK for you? On Fri, Sep 05, 2003 at 09:36:25AM -0700, John Cherry wrote: > Short story: > > The makefile changes separate targets with identical dependencies. In > the current Makefiles, things like "running the assembler" and "changing > file names" happen multiple times in parallel when building with > anything other than -j1. Consider the following example Makefile: > > targ: a b > a b: x > touch a b > x: > touch x > clean: > rm a b x > > Running the build with "make targ" yields: > touch x > touch a b > > Running the build with "make -j2 targ" yields: > touch x > touch a b > touch a b > > Notice that the "touch a b" output is not only executed twice, but on an > SMP machine, it could be run in parallel (with races). These two > patches separate the targets with the same dependencies and prevent > these races. I would actually consider this to be a bug in make, but > that is another story. Nope, consider the command to execute was: touch $@ - then it make all sense again. Sam ===== drivers/scsi/aic7xxx/Makefile 1.21 vs edited ===== --- 1.21/drivers/scsi/aic7xxx/Makefile Fri May 2 20:04:40 2003 +++ edited/drivers/scsi/aic7xxx/Makefile Fri Sep 5 21:14:01 2003 @@ -58,7 +58,13 @@ -p $(obj)/aic7xxx_reg_print.c -i aic7xxx_osm.h ifeq ($(CONFIG_AIC7XXX_BUILD_FIRMWARE),y) -$(aic7xxx-gen-y): $(src)/aic7xxx.seq $(src)/aic7xxx.reg $(obj)/aicasm/aicasm +$(aic7xxx-gen-y): $(src)/aic7xxx.seq $(src)/aic7xxx.reg +$(aic7xxx-gen-y): doaic7xasm + +.PHONY: doaic7xasm +$(aic7xxx-gen-y): doaic7xasm + +doaic7xasm: $(obj)/aicasm/aicasm $(obj)/aicasm/aicasm -I$(src) -r $(obj)/aic7xxx_reg.h \ $(aicasm-7xxx-opts-y) -o $(obj)/aic7xxx_seq.h \ $(src)/aic7xxx.seq @@ -72,7 +78,12 @@ -p $(obj)/aic79xx_reg_print.c -i aic79xx_osm.h ifeq ($(CONFIG_AIC79XX_BUILD_FIRMWARE),y) -$(aic79xx-gen-y): $(src)/aic79xx.seq $(src)/aic79xx.reg $(obj)/aicasm/aicasm +$(aic79xx-gen-y): $(src)/aic79xx.seq $(src)/aic79xx.reg + +.PHONY: doaic79asm +$(aic79xx-gen-y): doaic79asm + +doaic79asm: $(obj)/aicasm/aicasm $(obj)/aicasm/aicasm -I$(src) -r $(obj)/aic79xx_reg.h \ $(aicasm-79xx-opts-y) -o $(obj)/aic79xx_seq.h \ $(src)/aic79xx.seq ===== drivers/scsi/aic7xxx/aicasm/Makefile 1.11 vs edited ===== --- 1.11/drivers/scsi/aic7xxx/aicasm/Makefile Tue Mar 11 01:57:17 2003 +++ edited/drivers/scsi/aic7xxx/aicasm/Makefile Fri Sep 5 21:02:54 2003 @@ -49,14 +49,18 @@ clean: rm -f $(clean-files) -aicasm_gram.c aicasm_gram.h: aicasm_gram.y +aicasm_gram.c: aicasm_gram.h + mv $(<:.h=).tab.c $(<:.h=.c) + +aicasm_gram.h: aicasm_gram.y $(YACC) $(YFLAGS) -b $(<:.y=) $< - mv $(<:.y=).tab.c $(<:.y=.c) mv $(<:.y=).tab.h $(<:.y=.h) -aicasm_macro_gram.c aicasm_macro_gram.h: aicasm_macro_gram.y +aicasm_macro_gram.c: aicasm_macro_gram.h + mv $(<:.h=).tab.c $(<:.h=.c) + +aicasm_macro_gram.h: aicasm_macro_gram.y $(YACC) $(YFLAGS) -b $(<:.y=) -p mm $< - mv $(<:.y=).tab.c $(<:.y=.c) mv $(<:.y=).tab.h $(<:.y=.h) aicasm_scan.c: aicasm_scan.l - 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/