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Message-ID: <1372705721.22688.13.camel@gandalf.local.home>
Subject: Re: [PATCH v2 4/4] tracing/kprobes: Turn trace_probe->files into
 list_head
From: Steven Rostedt <rostedt@goodmis.org>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
        Srikar Dronamraju <srikar@linux.vnet.ibm.com>,
        "zhangwei(Jovi)" <jovi.zhangwei@huawei.com>,
        linux-kernel@vger.kernel.org
Date: Mon, 01 Jul 2013 15:08:41 -0400
In-Reply-To: <20130620173814.GA13165@redhat.com>
References: <20130620173814.GA13165@redhat.com>
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On Thu, 2013-06-20 at 19:38 +0200, Oleg Nesterov wrote:

> -static int
> -trace_probe_file_index(struct trace_probe *tp, struct ftrace_event_file *file)
> +static struct event_file_link *
> +find_event_file_link(struct trace_probe *tp, struct ftrace_event_file *file)
>  {
> -	struct ftrace_event_file **files;
> -	int i;
> +	struct event_file_link *link;
>  
> -	/*
> -	 * Since all tp->files updater is protected by probe_enable_lock,
> -	 * we don't need to lock an rcu_read_lock.
> -	 */
> -	files = rcu_dereference_raw(tp->files);
> -	if (files) {
> -		for (i = 0; files[i]; i++)
> -			if (files[i] == file)
> -				return i;
> -	}
> +	list_for_each_entry(link, &tp->files, list)
> +		if (link->file == file)
> +			return link;

Shouldn't that be list_for_each_entry_rcu()?

-- Steve

>  
> -	return -1;
> +	return NULL;
>  }
>  
>  /*