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Date:   Wed, 15 Jul 2020 20:12:12 -0400
From:   tytso@mit.edu
To:     Matthew Wilcox <willy@infradead.org>
Cc:     Andy Lutomirski <luto@amacapital.net>,
        Stefano Garzarella <sgarzare@redhat.com>,
        Miklos Szeredi <miklos@szeredi.hu>,
        Kees Cook <keescook@chromium.org>,
        Christian Brauner <christian.brauner@ubuntu.com>,
        strace-devel@lists.strace.io, io-uring@vger.kernel.org,
        Pavel Begunkov <asml.silence@gmail.com>,
        Linux API <linux-api@vger.kernel.org>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: strace of io_uring events?
Message-ID: <20200716001212.GA388817@mit.edu>
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On Wed, Jul 15, 2020 at 06:11:30PM +0100, Matthew Wilcox wrote:
> On Wed, Jul 15, 2020 at 07:35:50AM -0700, Andy Lutomirski wrote:
> > > On Jul 15, 2020, at 4:12 AM, Miklos Szeredi <miklos@szeredi.hu> wrote:
> > > This thread is to discuss the possibility of stracing requests
> > > submitted through io_uring.   I'm not directly involved in io_uring
> > > development, so I'm posting this out of  interest in using strace on
> > > processes utilizing io_uring.

> > > 
> > > Is there some existing tracing infrastructure that strace could use to
> > > get async completion events?  Should we be introducing one?

I suspect the best approach to use here is use eBPF, since since
sending asyncronously to a ring buffer is going to be *way* more
efficient than using the blocking ptrace(2) system call...

	       	     	 	  	    - Ted