From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Wangnan (F)" Subject: Re: [PATCH 1/8] tools lib bpf: add error functions Date: Wed, 19 Oct 2016 09:53:12 +0800 Message-ID: <5806D208.90308@huawei.com> References: <20161016211834.11732-1-eric@regit.org> <20161016211834.11732-2-eric@regit.org> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Cc: netdev , , To: Joe Stringer , Eric Leblond Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On 2016/10/19 6:52, Joe Stringer wrote: > On 16 October 2016 at 14:18, Eric Leblond wrote: >> The include of err.h is not explicitely needed in exported >> functions and it was causing include conflict with some existing >> code due to redefining some macros. >> >> To fix this, let's have error handling functions provided by the >> library. Furthermore this will allow user to have an homogeneous >> API. >> >> Signed-off-by: Eric Leblond > Does it need to return the error like this or should we just fix up > the bpf_object__open() API to return errors in a simpler form? > > There's already libbpf_set_print(...) for outputting errors, is it > reasonable to just change the library to return NULLs in error cases > instead? Returning error code to caller so caller knows what happen. Other subsystems in perf also do this. Perf hides libbpf's error output (make it silent unless -v), so it needs a way for receiving libbpf's error code. I think this patch is good, decouple libbpf.h and kernel headers. Thank you.