Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753271AbZCHPwd (ORCPT ); Sun, 8 Mar 2009 11:52:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753085AbZCHPwP (ORCPT ); Sun, 8 Mar 2009 11:52:15 -0400 Received: from hera.kernel.org ([140.211.167.34]:34111 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752872AbZCHPwN (ORCPT ); Sun, 8 Mar 2009 11:52:13 -0400 Date: Sun, 8 Mar 2009 15:51:33 GMT From: Mathieu Desnoyers To: linux-tip-commits@vger.kernel.org Cc: linux-kernel@vger.kernel.org, ananth@in.ibm.com, mathieu.desnoyers@polymtl.ca, hpa@zytor.com, mingo@redhat.com, tglx@linutronix.de, mhiramat@redhat.com, mingo@elte.hu Reply-To: mingo@redhat.com, hpa@zytor.com, mathieu.desnoyers@polymtl.ca, ananth@in.ibm.com, linux-kernel@vger.kernel.org, tglx@linutronix.de, mhiramat@redhat.com, mingo@elte.hu In-Reply-To: <49B14306.2080202@redhat.com> References: <49B14306.2080202@redhat.com> Subject: [tip:tracing/core] tracing, Text Edit Lock - kprobes architecture independent support Message-ID: Git-Commit-ID: 4460fdad85becd569f11501ad5b91814814335ff X-Mailer: tip-git-log-daemon MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.0 (hera.kernel.org [127.0.0.1]); Sun, 08 Mar 2009 15:51:35 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3516 Lines: 113 Commit-ID: 4460fdad85becd569f11501ad5b91814814335ff Gitweb: http://git.kernel.org/tip/4460fdad85becd569f11501ad5b91814814335ff Author: "Mathieu Desnoyers" AuthorDate: Fri, 6 Mar 2009 10:36:38 -0500 Commit: Ingo Molnar CommitDate: Fri, 6 Mar 2009 16:49:00 +0100 tracing, Text Edit Lock - kprobes architecture independent support Use the mutual exclusion provided by the text edit lock in the kprobes code. It allows coherent manipulation of the kernel code by other subsystems. Changelog: Move the kernel_text_lock/unlock out of the for loops. Use text_mutex directly instead of a function. Remove whitespace modifications. (note : kprobes_mutex is always taken outside of text_mutex) Signed-off-by: Mathieu Desnoyers Acked-by: Ananth N Mavinakayanahalli Acked-by: Masami Hiramatsu LKML-Reference: <49B14306.2080202@redhat.com> Signed-off-by: Ingo Molnar --- kernel/kprobes.c | 15 +++++++++++++-- 1 files changed, 13 insertions(+), 2 deletions(-) diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 7ba8cd9..479d4d5 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -43,6 +43,7 @@ #include #include #include +#include #include #include @@ -699,9 +700,10 @@ int __kprobes register_kprobe(struct kprobe *p) goto out; } + mutex_lock(&text_mutex); ret = arch_prepare_kprobe(p); if (ret) - goto out; + goto out_unlock_text; INIT_HLIST_NODE(&p->hlist); hlist_add_head_rcu(&p->hlist, @@ -710,6 +712,8 @@ int __kprobes register_kprobe(struct kprobe *p) if (kprobe_enabled) arch_arm_kprobe(p); +out_unlock_text: + mutex_unlock(&text_mutex); out: mutex_unlock(&kprobe_mutex); @@ -746,8 +750,11 @@ valid_p: * enabled and not gone - otherwise, the breakpoint would * already have been removed. We save on flushing icache. */ - if (kprobe_enabled && !kprobe_gone(old_p)) + if (kprobe_enabled && !kprobe_gone(old_p)) { + mutex_lock(&text_mutex); arch_disarm_kprobe(p); + mutex_unlock(&text_mutex); + } hlist_del_rcu(&old_p->hlist); } else { if (p->break_handler && !kprobe_gone(p)) @@ -1280,12 +1287,14 @@ static void __kprobes enable_all_kprobes(void) if (kprobe_enabled) goto already_enabled; + mutex_lock(&text_mutex); for (i = 0; i < KPROBE_TABLE_SIZE; i++) { head = &kprobe_table[i]; hlist_for_each_entry_rcu(p, node, head, hlist) if (!kprobe_gone(p)) arch_arm_kprobe(p); } + mutex_unlock(&text_mutex); kprobe_enabled = true; printk(KERN_INFO "Kprobes globally enabled\n"); @@ -1310,6 +1319,7 @@ static void __kprobes disable_all_kprobes(void) kprobe_enabled = false; printk(KERN_INFO "Kprobes globally disabled\n"); + mutex_lock(&text_mutex); for (i = 0; i < KPROBE_TABLE_SIZE; i++) { head = &kprobe_table[i]; hlist_for_each_entry_rcu(p, node, head, hlist) { @@ -1318,6 +1328,7 @@ static void __kprobes disable_all_kprobes(void) } } + mutex_unlock(&text_mutex); mutex_unlock(&kprobe_mutex); /* Allow all currently running kprobes to complete */ synchronize_sched(); -- 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/