[Xen-devel] [PATCH] build: Don't fetch tools/ioemu-dir unless needed

[George Dunlap <george.dunlap@xxxxxxxxxxxxx>]

c/s 18482 made both stubdom and tools dependent on tools/ioemu-dir
to fix a race condition where both build paths might try to fetch
qemu in parallel.  But this means that even if you build the tools
with CONFIG_IOEMU=n, qemu is still fetched first.

This patch causes tools/ioemu-dir to be a dependency for tools
only if CONFIG_IOEMU is enabled.

It's still unconditional for stubdoms, as it doesn't make much sense
to build stubdoms without it.

Signed-off-by: George Dunlap <george.dunlap@xxxxxxxxxxxxx>

diff -r 4b0692880dfa -r c3b9bca4b119 Config.mk
--- a/Config.mk Thu May 05 17:40:34 2011 +0100
+++ b/Config.mk Fri May 06 15:33:09 2011 +0100
@@ -179,6 +179,11 @@
 # CONFIG_QEMU ?= `pwd`/$(XEN_ROOT)/../qemu-xen.git
 CONFIG_QEMU ?= $(QEMU_REMOTE)
 
+# If building with CONFIG_IOEMU, get ioemu-dir before building
+# tools or stubdom (or they may race)
+SHARED_SUBDIRS-y :=
+SHARED_SUBDIRS-$(CONFIG_IOEMU) += tools/ioemu-dir
+
 QEMU_TAG := xen-4.1.0-rc6
 #QEMU_TAG ?= e073e69457b4d99b6da0b6536296e3498f7f6599
 # Fri Feb 11 17:54:51 2011 +0000
diff -r 4b0692880dfa -r c3b9bca4b119 Makefile
--- a/Makefile  Thu May 05 17:40:34 2011 +0100
+++ b/Makefile  Fri May 06 15:33:09 2011 +0100
@@ -66,7 +66,7 @@
        $(MAKE) -C xen install
 
 .PHONY: install-tools
-install-tools: tools/ioemu-dir
+install-tools: $(SHARED_SUBDIRS-y)
        $(MAKE) -C tools install
 
 .PHONY: install-kernels
@@ -74,6 +74,7 @@
        for i in $(XKERNELS) ; do $(MAKE) $$i-install || exit 1; done
 
 .PHONY: install-stubdom
+# NB: depend on tools/ioemu-dir unconditionally for stubdoms
 install-stubdom: tools/ioemu-dir install-tools
        $(MAKE) -C stubdom install
 ifeq (x86_64,$(XEN_TARGET_ARCH))

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel