[PATCH v4] perf: bpf: Fix build breakage due to libbpf

[Arnaldo Carvalho de Melo]

Em Thu, Jan 07, 2016 at 05:39:57PM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Thu, Jan 07, 2016 at 12:28:15PM +0530, Naveen N. Rao escreveu:
> > Can you please push at least the initial 3 patches of this for v4.4?  
> > Wang Nan has posted v6 here:
> > http://thread.gmane.org/gmane.linux.kernel/2110626
 
> So I tried it again today, from the v6, the latest patch with that
> subject line in my inbox, and I get this, after applying the first three
> patches:
 
> [acme at zoo linux]$ make -C tools clean > /dev/null
> [acme at zoo linux]$ make -C tools/perf build-test
> make: Entering directory '/home/git/linux/tools/perf'
> Testing Makefile
> tests/make:15: /scripts/Makefile.arch: No such file or directory
> make[2]: *** No rule to make target '/scripts/Makefile.arch'.  Stop.
> tests/make:5: recipe for target 'all' failed
> make[1]: *** [all] Error 2
> Makefile:81: recipe for target 'build-test' failed
> make: *** [build-test] Error 2
> make: Leaving directory '/home/git/linux/tools/perf'
> [acme at zoo linux]$

> Trying to figure this out...

So, this doesn't seem to have been tessted, this part, specifically:

diff --git a/tools/perf/tests/make b/tools/perf/tests/make
index 8ea3dffc5065..cd9c3ce1a5c2 100644
--- a/tools/perf/tests/make
+++ b/tools/perf/tests/make
@@ -12,7 +12,7 @@ endif
 else
 PERF := .
 
-include config/Makefile.arch
+include $(srctree)/scripts/Makefile.arch
 
 # FIXME looks like x86 is the only arch running tests ;-)
 # we need some IS_(32/64) flag to make this generic


----------------------------------------------------

Because $(srctree) is not set at that point, I copied the needed bits from
tools/perf/Makefile.perf and got the patch below, which makes:L

  make -C tools/perf build-test

Work for me again.

This should wrap up the day nicely, making me think of Jens Axboe recent
cool reaction to an untested patch:

http://lkml.kernel.org/r/5661C2BC.9030007@kernel.dk

:-)

Jiri, are you ok with the patch below, on top of the second patch in
Wang's series, that you acked?

- Arnaldo

diff --git a/tools/perf/tests/make b/tools/perf/tests/make
index cd9c3ce1a5c2..377654f862ec 100644
--- a/tools/perf/tests/make
+++ b/tools/perf/tests/make
@@ -1,3 +1,5 @@
+include ../scripts/Makefile.include
+
 ifndef MK
 ifeq ($(MAKECMDGOALS),)
 # no target specified, trigger the whole suite
@@ -12,7 +14,19 @@ endif
 else
 PERF := .
 
-include $(srctree)/scripts/Makefile.arch
+# As per kernel Makefile, avoid funny character set dependencies
+unexport LC_ALL
+LC_COLLATE=C
+LC_NUMERIC=C
+export LC_COLLATE LC_NUMERIC
+
+ifeq ($(srctree),)
+srctree := $(patsubst %/,%,$(dir $(shell pwd)))
+srctree := $(patsubst %/,%,$(dir $(srctree)))
+#$(info Determined 'srctree' to be $(srctree))
+endif
+
+include $(srctree)/tools/scripts/Makefile.arch
 
 # FIXME looks like x86 is the only arch running tests ;-)
 # we need some IS_(32/64) flag to make this generic