From: Oleg Nesterov <oleg@redhat.com>
To: "zhangwei(Jovi)" <jovi.zhangwei@huawei.com>,
Steven Rostedt <rostedt@goodmis.org>,
Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>,
Ingo Molnar <mingo@redhat.com>,
Srikar Dronamraju <srikar@linux.vnet.ibm.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: ftrace multibuffer && rcu (Was: tracing/uprobes: Support ftrace_event_file base multibuffer)
Date: Fri, 14 Jun 2013 18:18:37 +0200 [thread overview]
Message-ID: <20130614161837.GA15268@redhat.com> (raw)
In-Reply-To: <20130614160456.GA14726@redhat.com>
On 06/14, Oleg Nesterov wrote:
>
> So perhaps something like below (untested) makes sense? With this patch
> we can trivially convert trace_kprobe.c to use list_add/del/each_rcu.
Forgot to mention, the patch is obviously incomplete, __kprobe_trace_func()
can see the "dead" file even if its memory can't go away. But this looks
fixable.
> +static inline struct event_file_link *
> +alloc_event_file_link(struct ftrace_event_file *file)
> +{
> + struct event_file_link *link = kmalloc(sizeof(*link), GFP_KERNEL);
> + if (link)
> + link->file = file;
> + return link;
> +}
And this lacks atomic_inc(file->refcnt).
In short, this is just to explain what I meant, the actual change should
probably differ.
Oleg.
next prev parent reply other threads:[~2013-06-14 16:23 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-06-14 1:44 [PATCH] tracing/uprobes: Support ftrace_event_file base multibuffer zhangwei(Jovi)
2013-06-14 13:21 ` Masami Hiramatsu
2013-06-14 13:51 ` Oleg Nesterov
2013-06-14 14:09 ` Oleg Nesterov
2013-06-14 15:31 ` Steven Rostedt
2013-06-14 16:21 ` Paul E. McKenney
2013-06-14 16:33 ` Steven Rostedt
2013-06-14 17:25 ` Paul E. McKenney
2013-06-17 2:54 ` Masami Hiramatsu
2013-06-17 12:33 ` Steven Rostedt
2013-06-18 1:31 ` Masami Hiramatsu
2013-06-18 2:02 ` Steven Rostedt
2013-06-14 14:44 ` Oleg Nesterov
2013-06-14 16:04 ` ftrace multibuffer && rcu (Was: tracing/uprobes: Support ftrace_event_file base multibuffer) Oleg Nesterov
2013-06-14 16:18 ` Oleg Nesterov [this message]
2013-06-14 16:26 ` Steven Rostedt
2013-06-14 17:02 ` Oleg Nesterov
2013-06-20 16:43 ` [PATCH] tracing/uprobes: Support ftrace_event_file base multibuffer Oleg Nesterov
2013-06-21 8:17 ` zhangwei(Jovi)
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