From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753050AbbIFHSf (ORCPT ); Sun, 6 Sep 2015 03:18:35 -0400 Received: from szxga03-in.huawei.com ([119.145.14.66]:54481 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751516AbbIFHOq (ORCPT ); Sun, 6 Sep 2015 03:14:46 -0400 From: Wang Nan To: , , , CC: , , , , , , , , , , , Subject: [PATCH 18/27] perf tools: Add BPF_PROLOGUE config options for further patches Date: Sun, 6 Sep 2015 07:13:34 +0000 Message-ID: <1441523623-152703-19-git-send-email-wangnan0@huawei.com> X-Mailer: git-send-email 1.8.3.4 In-Reply-To: <1441523623-152703-1-git-send-email-wangnan0@huawei.com> References: <1441523623-152703-1-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 X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A090202.55EBE7CF.0073,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: bdc88fbd9c5d819f6aacb817f3767fdd Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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_REGS_QUERY_REGISTER_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. HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET is introduced as the corresponding CFLAGS of PERF_HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET. 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/1441090789-108382-2-git-send-email-wangnan0@huawei.com [wangnan: - Simplify Makefile based on Namhyung Kim's suggestion. ] --- tools/perf/config/Makefile | 17 +++++++++++++++++ tools/perf/util/include/dwarf-regs.h | 8 ++++++++ 2 files changed, 25 insertions(+) diff --git a/tools/perf/config/Makefile b/tools/perf/config/Makefile index 38a4144..25c9ffc 100644 --- a/tools/perf/config/Makefile +++ b/tools/perf/config/Makefile @@ -110,6 +110,11 @@ FEATURE_CHECK_CFLAGS-bpf = -I. -I$(srctree)/tools/include -I$(srctree)/arch/$(AR # include ARCH specific config -include $(src-perf)/arch/$(ARCH)/Makefile +ifdef PERF_HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET + CFLAGS += -DHAVE_ARCH_REGS_QUERY_REGISTER_OFFSET +endif + + include $(src-perf)/config/utilities.mak ifeq ($(call get-executable,$(FLEX)),) @@ -314,6 +319,18 @@ ifndef NO_LIBELF CFLAGS += -DHAVE_LIBBPF_SUPPORT $(call detected,CONFIG_LIBBPF) endif + + ifndef NO_DWARF + ifdef PERF_HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET + CFLAGS += -DHAVE_BPF_PROLOGUE + $(call detected,CONFIG_BPF_PROLOGUE) + else + msg := $(warning BPF prologue is not supported by architecture $(ARCH), missing regs_query_register_offset()); + 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..07c644e 100644 --- a/tools/perf/util/include/dwarf-regs.h +++ b/tools/perf/util/include/dwarf-regs.h @@ -5,4 +5,12 @@ const char *get_arch_regstr(unsigned int n); #endif +#ifdef HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET +/* + * Arch should support fetching the offset of a register in pt_regs + * by its name. See kernel's regs_query_register_offset in + * arch/xxx/kernel/ptrace.c. + */ +int regs_query_register_offset(const char *name); +#endif #endif -- 2.1.0