@Stephen Hemminger
Xiaoyun proposed a solution which may match your idea, but there are some
concerns:
1. a global variable for original terminal setting has to be defined.
2. in each app which uses cmdline, a function has to be registered with
atexit() in prompt() to restore original terminal setting.
@Stephen Hemminger, can you give some feedback on these concerns? Thanks!
-----Original Message-----
From: Li, Xiaoyun
Sent: Friday, January 15, 2021 5:22 PM
To: Xing, Beilei <[email protected]>; Yu, DapengX <[email protected]>;
Lu, Wenzhuo <[email protected]>; Iremonger, Bernard
<[email protected]>; Stephen Hemminger <[email protected]>
Cc: [email protected]; [email protected]
Subject: RE: [dpdk-dev] [PATCH] app/testpmd: avoid exit without resource release
Hi
Actually, you can just type "stty echo" to solve the problem you met.
But anyway, if you want to fix it in DPDK I think you misunderstood stephan's
solution.
You don't need to implement atexit() yourself in eal. It's a common function
like exit() in rte_exit().
Then when exit() is called. Each function registered by atexit() will be called
in stack order.
The simplest way to solve this problem is to register a function with atexit()
in prompt() in each app which uses cmdline.
Then when exit() in rte_exit() is called, the registered clean function will be
called directly.
Registering in prompt() is because that prompt() is the function which starts
cmdline in each app.
@Stephen Hemminger What do you think of this about atexit() in prompt() in each
app?
I understand it's cmdline and rte_exit problem. But atexit needs a function
without parameters.
And the cleanup for cmdline is cmdline_stdin_exit(struct cmdline *cl) which
needs cmdline as the parameter to restore original terminal setting.
Setting a global value will be too ugly to me.
BRs
Xiaoyun
> -----Original Message-----
> From: stable <[email protected]> On Behalf Of Xing, Beilei
> Sent: Friday, January 15, 2021 13:50
> To: Yu, DapengX <[email protected]>; Lu, Wenzhuo
> <[email protected]>; Iremonger, Bernard
> <[email protected]>
> Cc: Stephen Hemminger <[email protected]>; [email protected];
> [email protected]
> Subject: Re: [dpdk-stable] [dpdk-dev] [PATCH] app/testpmd: avoid exit
> without resource release
>
> > -----Original Message-----
> > From: Yu, DapengX <[email protected]>
> > Sent: Friday, January 15, 2021 11:29 AM
> > To: Lu, Wenzhuo <[email protected]>; Xing, Beilei
> > <[email protected]>; Iremonger, Bernard
> > <[email protected]>
> > Cc: Yu, DapengX <[email protected]>; Stephen Hemminger
> > <[email protected]>; [email protected]; [email protected]
> > Subject: RE: [dpdk-dev] [PATCH] app/testpmd: avoid exit without
> > resource release
> >
> > Hi Wenzhuo, Beilei, Bernard
> >
> > I need testpmd app maintainers' comment :
> > Do you prefer the simple solution in this patch or Stephen's
> > comprehensive and generic solution(which will modify librte_cmdline,
> > testpmd (and maybe rte_exit()))?
>
> The patch just workarounds a specific case, the issue exits in many
> cases, such as Rxonly mode and Rxq is 0.
> So It's better to investigate how to solve the generic problem
> according to Stephen's comments.
>
> > So I can continue resolving the defect.
> >
> > Thanks!
> >
> > -----Original Message-----
> > From: dev [mailto:[email protected]] On Behalf Of Yu, DapengX
> > Sent: Friday, December 25, 2020 1:09 PM
> > To: Stephen Hemminger <[email protected]>
> > Cc: Lu, Wenzhuo <[email protected]>; Xing, Beilei
> > <[email protected]>; Iremonger, Bernard
> > <[email protected]>; [email protected]; [email protected]
> > Subject: Re: [dpdk-dev] [PATCH] app/testpmd: avoid exit without
> > resource release
> >
> > Hi Stephen,
> >
> > Do you mean this solution?
> > 1. support atexit() in librte_eal, other component can use it to
> > register a function to be called when rte_exit() is called.
> > 2. in librte_cmdline, use atexit() to register a function to release
> > resource
> >
> > I am looking forward to more comments from other maintainers, since
> > this solution will modify librte_eal and librte_cmdline, but not just
> > testpmd app.
> >
> >
> > -----Original Message-----
> > From: Stephen Hemminger [mailto:[email protected]]
> > Sent: Friday, December 25, 2020 11:03 AM
> > To: Yu, DapengX <[email protected]>
> > Cc: Lu, Wenzhuo <[email protected]>; Xing, Beilei
> > <[email protected]>; Iremonger, Bernard
> > <[email protected]>; [email protected]; [email protected]
> > Subject: Re: [dpdk-dev] [PATCH] app/testpmd: avoid exit without
> > resource release
> >
> > On Thu, 24 Dec 2020 11:57:48 +0800
> > [email protected] wrote:
> >
> > > From: YU DAPENG <[email protected]>
> > >
> > > In interactive mode, if testpmd exit by calling rte_exit without
> > > cmdline resource release, terminal will not echo keyboard input.
> > > So add code to just show error message, but not exit testpmd when
> > > unexpected happens on starting packet forwarding in interactive
> > > mode. User
> > can type "quit"
> > > to exit testpmd later.
> > >
> > > Fixes: 5a8fb55c48ab ("app/testpmd: support unidirectional
> > > configuration")
> > > Cc: [email protected]
> > >
> > > Signed-off-by: YU DAPENG <[email protected]>
> >
> > Sounds like a more generic problem with rte_exit and librte_cmdline.
> > Would it better to fix it in librte_cmdline by adding an atexit() handler.
> >
