From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754113AbbGIMnH (ORCPT ); Thu, 9 Jul 2015 08:43:07 -0400 Received: from szxga03-in.huawei.com ([119.145.14.66]:34376 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753222AbbGIMm4 (ORCPT ); Thu, 9 Jul 2015 08:42:56 -0400 From: Wang Nan To: , CC: , , , , Subject: [PATCH 32/39] perf tools: Add BPF_PROLOGUE config options for further patches Date: Thu, 9 Jul 2015 12:35:35 +0000 Message-ID: <1436445342-1402-33-git-send-email-wangnan0@huawei.com> X-Mailer: git-send-email 1.8.3.4 In-Reply-To: <1436445342-1402-1-git-send-email-wangnan0@huawei.com> References: <1436445342-1402-1-git-send-email-wangnan0@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.107.197.200] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020201.559E6ABD.0185,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2013-05-26 15:14:31, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: f600ccefacc211d3929216df68044a34 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If both LIBBPF and DWARF is 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 --- 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 52722cf..d776f32 100644 --- a/tools/perf/config/Makefile +++ b/tools/perf/config/Makefile @@ -310,6 +310,18 @@ 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)); + 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 +#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 -- 1.8.3.4