Re: [PATCH] sample/bpf: Make perf_event_read() static

From: Daniel Borkmann
Date: Thu Dec 15 2016 - 10:49:25 EST


On 12/15/2016 04:29 PM, Arnaldo Carvalho de Melo wrote:

While testing Joe's conversion of samples/bpf/ to use tools/lib/bpf/ I
noticed some warnings, do you guys mind if I put patches like the one
below in my tree, pushing to Ingo soon?

Or is there anything subtle against doing so?

Fwiw, no objections from my side, there is currently nothing in
net/net-next tree that could cause conflicts regarding the below
change, so should be good to take this route instead.

----

While building samples/bpf/ on a Fedora Rawhide container, with
clang/llvm 3.9 I noticed this:

root@1e797fdfbf4f linux]# make -j4 O=/tmp/build/linux/ samples/bpf/
make[1]: Entering directory '/tmp/build/linux'
CHK include/config/kernel.release
GEN ./Makefile
CHK include/generated/uapi/linux/version.h
Using /git/linux as source for kernel
<SNIP>
HOSTCC samples/bpf/trace_output_user.o
/git/linux/samples/bpf/trace_output_user.c:64:6: warning: no previous
prototype for 'perf_event_read' [-Wmissing-prototypes]
void perf_event_read(print_fn fn)
^~~~~~~~~~~~~~~
HOSTLD samples/bpf/trace_output
make[1]: Leaving directory '/tmp/build/linux'

Shutup the compiler by setting that function as static.

Cc: Alexei Starovoitov <ast@xxxxxx>
Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Cc: Wang Nan <wangnan0@xxxxxxxxxx>,
Cc: Joe Stringer <joe@xxxxxxx>
Link: http://lkml.kernel.org/n/tip-2wkr4ymwhdie0stbkbiyplt5@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>

Acked-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>

Thanks,
Daniel