Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753749AbbHJGUK (ORCPT ); Mon, 10 Aug 2015 02:20:10 -0400 Received: from szxga02-in.huawei.com ([119.145.14.65]:47932 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754697AbbHJGRs (ORCPT ); Mon, 10 Aug 2015 02:17:48 -0400 From: Wang Nan To: , CC: , , , , , , , , , , , , Subject: [PATCH 20/27] perf tools: Add BPF_PROLOGUE config options for further patches Date: Mon, 10 Aug 2015 06:16:02 +0000 Message-ID: <1439187369-66492-21-git-send-email-wangnan0@huawei.com> X-Mailer: git-send-email 1.8.3.4 In-Reply-To: <1439187369-66492-1-git-send-email-wangnan0@huawei.com> References: <1439187369-66492-1-git-send-email-wangnan0@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.107.193.248] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2656 Lines: 76 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 1b99385..6771318 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 -- 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/