Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752459AbbHaUjN (ORCPT ); Mon, 31 Aug 2015 16:39:13 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54008 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751129AbbHaUjL (ORCPT ); Mon, 31 Aug 2015 16:39:11 -0400 Date: Mon, 31 Aug 2015 17:39:08 -0300 From: Arnaldo Carvalho de Melo To: Wang Nan Cc: mingo@kernel.org, ast@plumgrid.com, linux-kernel@vger.kernel.org, lizefan@huawei.com, pi3orama@163.com, Brendan Gregg , Daniel Borkmann , David Ahern , He Kuang , Jiri Olsa , Kaixu Xia , Masami Hiramatsu , Namhyung Kim , Paul Mackerras , Peter Zijlstra Subject: Re: [PATCH 22/31] perf tools: Add BPF_PROLOGUE config options for further patches Message-ID: <20150831203908.GD2443@redhat.com> References: <1440822125-52691-1-git-send-email-wangnan0@huawei.com> <1440822125-52691-23-git-send-email-wangnan0@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1440822125-52691-23-git-send-email-wangnan0@huawei.com> X-Url: http://acmel.wordpress.com User-Agent: Mutt/1.5.20 (2009-12-10) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3179 Lines: 87 Em Sat, Aug 29, 2015 at 04:21:56AM +0000, Wang Nan escreveu: > If both LIBBPF and DWARF are detected, it is possible to create prologue > for eBPF programs to help them accessing kernel data. HAVE_BPF_PROLOGUE > and CONFIG_BPF_PROLOGUE is added as flags for this feature. > > PERF_HAVE_ARCH_GET_REG_OFFSET indicates an architecture supports > converting name of a register to its offset in 'struct pt_regs'. > Without this support, BPF_PROLOGUE should be turned off. > > Signed-off-by: Wang Nan > Cc: Alexei Starovoitov > Cc: Brendan Gregg > Cc: Daniel Borkmann > Cc: David Ahern > Cc: He Kuang > Cc: Jiri Olsa > Cc: Kaixu Xia > Cc: Masami Hiramatsu > Cc: Namhyung Kim > Cc: Paul Mackerras > Cc: Peter Zijlstra > Cc: Zefan Li > Cc: pi3orama@163.com > Cc: Arnaldo Carvalho de Melo > Link: http://lkml.kernel.org/n/1436445342-1402-33-git-send-email-wangnan0@huawei.com > --- > tools/perf/config/Makefile | 12 ++++++++++++ > tools/perf/util/include/dwarf-regs.h | 7 +++++++ > 2 files changed, 19 insertions(+) > > diff --git a/tools/perf/config/Makefile b/tools/perf/config/Makefile > index 38a4144..d46765b7 100644 > --- a/tools/perf/config/Makefile > +++ b/tools/perf/config/Makefile > @@ -314,6 +314,18 @@ ifndef NO_LIBELF > CFLAGS += -DHAVE_LIBBPF_SUPPORT > $(call detected,CONFIG_LIBBPF) > endif > + > + ifndef NO_DWARF > + ifneq ($(origin PERF_HAVE_ARCH_GET_REG_INFO), undefined) > + CFLAGS += -DHAVE_BPF_PROLOGUE > + $(call detected,CONFIG_BPF_PROLOGUE) > + else > + msg := $(warning BPF prologue is not supported by architecture $(ARCH)); Shouldn't this be replace to something like: msg := $(warning BPF prologue is not supported by architecture $(ARCH), missing ARCH_GET_REG_INFO); Or even in lowercase? > + endif > + else > + msg := $(warning DWARF support is off, BPF prologue is disabled); > + endif > + > endif # NO_LIBBPF > endif # NO_LIBELF > > diff --git a/tools/perf/util/include/dwarf-regs.h b/tools/perf/util/include/dwarf-regs.h > index 8f14965..3dda083 100644 > --- a/tools/perf/util/include/dwarf-regs.h > +++ b/tools/perf/util/include/dwarf-regs.h > @@ -5,4 +5,11 @@ > const char *get_arch_regstr(unsigned int n); > #endif Shouldn't this test against PERF_HAVE_ARCH_GET_REG_INFO instead? I.e. is arch_get_reg_info() only allowed to work with eBPF? I guess not, right? > +#ifdef HAVE_BPF_PROLOGUE > +/* > + * Arch should support fetching the offset of a register in pt_regs > + * by its name. > + */ > +int arch_get_reg_info(const char *name, int *offset); > +#endif > #endif > -- > 2.1.0 -- 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/