linux-kernel - Re: [PATCH v3] tracing: Support to dump instance traces by ftrace_dump_on

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20240123103907.636c1840@gandalf.local.home>
Date: Tue, 23 Jan 2024 10:39:07 -0500
From: Steven Rostedt <rostedt@...dmis.org>
To: Huang Yiwei <quic_hyiwei@...cinc.com>
Cc: <mhiramat@...nel.org>, <mark.rutland@....com>, <mcgrof@...nel.org>,
 <keescook@...omium.org>, <j.granados@...sung.com>,
 <mathieu.desnoyers@...icios.com>, <corbet@....net>,
 <linux-kernel@...r.kernel.org>, <linux-trace-kernel@...r.kernel.org>,
 <linux-fsdevel@...r.kernel.org>, <linux-doc@...r.kernel.org>,
 <quic_bjorande@...cinc.com>, <quic_tsoni@...cinc.com>,
 <quic_satyap@...cinc.com>, <quic_aiquny@...cinc.com>, <kernel@...cinc.com>,
 Ross Zwisler <zwisler@...gle.com>, Joel Fernandes <joel@...lfernandes.org>
Subject: Re: [PATCH v3] tracing: Support to dump instance traces by
 ftrace_dump_on_oops

On Tue, 23 Jan 2024 09:49:00 -0500
Steven Rostedt <rostedt@...dmis.org> wrote:

> On Tue, 23 Jan 2024 18:23:58 +0800
> Huang Yiwei <quic_hyiwei@...cinc.com> wrote:
> 
> > > And if we really want to be fancy!
> > > 
> > > 	ftrace_dump_on_opps[=orig_cpu | =<instance> | =orig_cpu:<instance> ][,<instance> | ,<instance>:orig_cpu]
> > >     
> > Yeah, I agree to make the parameter more flexible.
> > 
> > "=orig_cpu:<instance>" means to dump global and another instance?  
> 
> No, I added a comma for that:
> 
>   =,orig_cpu:<instance>
> 
> Would mean to dump all of global and just the origin CPU of the instance.
> 
> > 
> > I'm thinking of the following format:
> > 
> > ftrace_dump_on_opps[=orig_cpu | =<instance>][,<instance> | 
> > ,<instance>=orig_cpu]
> > 
> > Here list some possible situations:
> > 
> > 1. Dump global on orig_cpu:
> > ftrace_dump_on_oops=orig_cpu
> > 
> > 2. Dump global and instance1 on all cpu, instance2 on orig_cpu:
> > ftrace_dump_on_opps,<instance1>,<instance2>=orig_cpu
> > 
> > 3. Dump global and instance1 on orig_cpu, instance2 on all cpu:
> > ftrace_dump_on_opps=orig_cpu,<instance1>=orig_cpu,<instance2>
> > 
> > 4. Dump instance1 on all cpu, instance2 on orig_cpu:
> > ftrace_dump_on_opps=<instance1>,<instance2>=orig_cpu
> > 
> > 5. Dump instance1 and instance2 on orig_cpu:
> > ftrace_dump_on_opps=<instance1>=orig_cpu,<instance2>=orig_cpu
> > 
> > This makes orig_cpu dump for global same as instance, the parameter may 
> > seems more unified and users don't need to remember another markers to 
> > request orig_cpu dump.
> > 
> > But one problem here is if there's an instance named "orig_cpu", then we 
> > may not dump it correctly.  
> 
> I would put that under:
> 
>    Patient: Doctor it hurts me when I do this
>    Doctor:  Then don't do that
> 
> ;-)

Oh, and I'm fine with what you proposed above.

-- Steve