From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752694Ab0FWKEX (ORCPT ); Wed, 23 Jun 2010 06:04:23 -0400 Received: from e23smtp01.au.ibm.com ([202.81.31.143]:37648 "EHLO e23smtp01.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752452Ab0FWKEH (ORCPT ); Wed, 23 Jun 2010 06:04:07 -0400 From: "Ian Munsie" To: linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org Cc: Jason Baron , Frederic Weisbecker , Steven Rostedt , Ingo Molnar , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Ian Munsie , Randy Dunlap , Mike Frysinger , Heiko Carstens , Masami Hiramatsu , linux-doc@vger.kernel.org Subject: [PATCH 02/40] ftrace syscalls: Make arch_syscall_addr weak Date: Wed, 23 Jun 2010 20:02:43 +1000 Message-Id: <1277287401-28571-3-git-send-email-imunsie@au1.ibm.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1277287401-28571-1-git-send-email-imunsie@au1.ibm.com> References: <1277287401-28571-1-git-send-email-imunsie@au1.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ian Munsie Some architectures use non-trivial system call tables and will not work with the generic arch_syscall_addr code. For example, PowerPC64 uses a table of twin long longs. This patch makes the generic arch_syscall_addr weak to allow architectures with non-trivial system call tables to override it. Signed-off-by: Ian Munsie --- Documentation/trace/ftrace-design.txt | 3 +++ kernel/trace/trace_syscalls.c | 2 +- 2 files changed, 4 insertions(+), 1 deletions(-) diff --git a/Documentation/trace/ftrace-design.txt b/Documentation/trace/ftrace-design.txt index f1f81af..8369a1c 100644 --- a/Documentation/trace/ftrace-design.txt +++ b/Documentation/trace/ftrace-design.txt @@ -244,6 +244,9 @@ You need very few things to get the syscalls tracing in an arch. - Support the TIF_SYSCALL_TRACEPOINT thread flags. - Put the trace_sys_enter() and trace_sys_exit() tracepoints calls from ptrace in the ptrace syscalls tracing path. +- If the system call table on this arch is more complicated than a simple array + of addresses of the system calls, implement an arch_syscall_addr to return + the address of a given system call. - Tag this arch as HAVE_SYSCALL_TRACEPOINTS. diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index 82246ce..e2b657e 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -453,7 +453,7 @@ int init_syscall_trace(struct ftrace_event_call *call) return id; } -unsigned long __init arch_syscall_addr(int nr) +unsigned long __init __weak arch_syscall_addr(int nr) { return (unsigned long)sys_call_table[nr]; } -- 1.7.1