Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750929AbZGWEBi (ORCPT ); Thu, 23 Jul 2009 00:01:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750754AbZGWEBh (ORCPT ); Thu, 23 Jul 2009 00:01:37 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:52239 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1750712AbZGWEBh (ORCPT ); Thu, 23 Jul 2009 00:01:37 -0400 Message-ID: <4A67E092.3080202@cn.fujitsu.com> Date: Thu, 23 Jul 2009 12:01:22 +0800 From: Xiao Guangrong User-Agent: Thunderbird 2.0.0.6 (Windows/20070728) MIME-Version: 1.0 To: Ingo Molnar CC: "K.Prasad" , Alan Stern , Frederic Weisbecker , Steven Rostedt , LKML Subject: [PATCH 3/3] tracing/ksym_tracer: support quick clear for ksym_trace_filter -- v2 References: <4A6685BB.2090809@cn.fujitsu.com> <4A66869A.9000106@cn.fujitsu.com> In-Reply-To: <4A66869A.9000106@cn.fujitsu.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3337 Lines: 116 It's rather bored to clear symbol one by one in ksym_trace_filter file, so, this patch can let ksym_trace_filter file support quick clear, we can write "0" to this file, it can clear all symbols for example: # cat ksym_trace_filter ksym_filter_head:rw- global_trace:rw- # echo 0 > ksym_trace_filter # cat ksym_trace_filter # Changelog v1->v2: Add other way to clear all breakpoints by writing NULL or "*:---" to ksym_trace_filter file base on K.Prasad's suggestion Signed-off-by: Xiao Guangrong --- kernel/trace/trace_ksym.c | 53 +++++++++++++++++++++++++++++--------------- 1 files changed, 35 insertions(+), 18 deletions(-) diff --git a/kernel/trace/trace_ksym.c b/kernel/trace/trace_ksym.c index cd5cb65..2fde875 100644 --- a/kernel/trace/trace_ksym.c +++ b/kernel/trace/trace_ksym.c @@ -163,8 +163,6 @@ static int parse_ksym_trace_str(char *input_string, char **ksymname, { int ret; - strstrip(input_string); - *ksymname = strsep(&input_string, ":"); *addr = kallsyms_lookup_name(*ksymname); @@ -262,6 +260,25 @@ static ssize_t ksym_trace_filter_read(struct file *filp, char __user *ubuf, return cnt; } +static void __ksym_trace_reset(void) +{ + struct trace_ksym *entry; + struct hlist_node *node, *node1; + + mutex_lock(&ksym_tracer_mutex); + hlist_for_each_entry_safe(entry, node, node1, &ksym_filter_head, + ksym_hlist) { + unregister_kernel_hw_breakpoint(entry->ksym_hbp); + ksym_filter_entry_count--; + hlist_del_rcu(&(entry->ksym_hlist)); + synchronize_rcu(); + kfree(entry->ksym_hbp->info.name); + kfree(entry->ksym_hbp); + kfree(entry); + } + mutex_unlock(&ksym_tracer_mutex); +} + static ssize_t ksym_trace_filter_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos) @@ -282,6 +299,21 @@ static ssize_t ksym_trace_filter_write(struct file *file, } input_string[count] = '\0'; + strstrip(input_string); + + /* + * Clear all breakpoints if: + * 1: echo > ksym_trace_filter + * 2: echo 0 > ksym_trace_filter + * 3: echo "*:---" > ksym_trace_filter + */ + if (!input_string[0] || !strcmp(input_string, "0") || + !strcmp(input_string, "*:---")) { + __ksym_trace_reset(); + kfree(input_string); + return count; + } + ret = op = parse_ksym_trace_str(input_string, &ksymname, &ksym_addr); if (ret < 0) { kfree(input_string); @@ -341,23 +373,8 @@ static const struct file_operations ksym_tracing_fops = { static void ksym_trace_reset(struct trace_array *tr) { - struct trace_ksym *entry; - struct hlist_node *node, *node1; - ksym_tracing_enabled = 0; - - mutex_lock(&ksym_tracer_mutex); - hlist_for_each_entry_safe(entry, node, node1, &ksym_filter_head, - ksym_hlist) { - unregister_kernel_hw_breakpoint(entry->ksym_hbp); - ksym_filter_entry_count--; - hlist_del_rcu(&(entry->ksym_hlist)); - synchronize_rcu(); - kfree(entry->ksym_hbp->info.name); - kfree(entry->ksym_hbp); - kfree(entry); - } - mutex_unlock(&ksym_tracer_mutex); + __ksym_trace_reset(); } static int ksym_trace_init(struct trace_array *tr) -- 1.6.1.2 -- 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/