[dpdk-dev] doc: add a restriction to multi-process support

From: Junjie Chen <junjie.j.chen@intel.com>

This patch add a restriction to multi-process support: secondary
processes should only run alongside primary process with same DPDK 
version, so that secondary processes can use the same hugepage mmap
layout as primary process.

Signed-off-by: Junjie Chen <junjie.j.chen@intel.com>
---
 doc/guides/prog_guide/multi_proc_support.rst | 1 +
 doc/guides/tools/proc_info.rst               | 3 ++-
 2 files changed, 3 insertions(+), 1 deletion(-)

On Tue, Nov 28, 2017 at 04:56:54AM -0500, junjie.j.chen@intel.com wrote:
> From: Junjie Chen <junjie.j.chen@intel.com>
> 
> This patch add a restriction to multi-process support: secondary
> processes should only run alongside primary process with same DPDK 
> version, so that secondary processes can use the same hugepage mmap
> layout as primary process.
> 
> Signed-off-by: Junjie Chen <junjie.j.chen@intel.com>
> ---
>  doc/guides/prog_guide/multi_proc_support.rst | 1 +
>  doc/guides/tools/proc_info.rst               | 3 ++-
>  2 files changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/doc/guides/prog_guide/multi_proc_support.rst b/doc/guides/prog_guide/multi_proc_support.rst
> index 9a9dca7fe..0cd67ae2d 100644
> --- a/doc/guides/prog_guide/multi_proc_support.rst
> +++ b/doc/guides/prog_guide/multi_proc_support.rst
> @@ -51,6 +51,7 @@ For now, there are two types of process specified:
>  Standalone DPDK processes are primary processes,
>  while secondary processes can only run alongside a primary process or
>  after a primary process has already configured the hugepage shared memory for them.
> +And secondary processes should only run alongside primary process with same DPDK version.
>  
>  To support these two process types, and other multi-process setups described later,
>  two additional command-line parameters are available to the EAL:
> diff --git a/doc/guides/tools/proc_info.rst b/doc/guides/tools/proc_info.rst
> index fd17e278c..512fd3263 100644
> --- a/doc/guides/tools/proc_info.rst
> +++ b/doc/guides/tools/proc_info.rst
> @@ -36,7 +36,8 @@ The dpdk-procinfo application is a Data Plane Development Kit (DPDK) application
>  that runs as a DPDK secondary process and is capable of retrieving port
>  statistics, resetting port statistics and printing DPDK memory information.
>  This application extends the original functionality that was supported by
> -dump_cfg.
> +dump_cfg. Note that dpdk-procinfo can only run alongside primary process with 
> +same DPDK version.
>  
>  Running the Application
>  -----------------------
> -- 
Good to add to the docs. I suggest that you add them using the proper
"note" markup to make it clearer in the docs.

/Bruce

> -----Original Message-----
> From: Richardson, Bruce
> Sent: Tuesday, November 28, 2017 7:22 PM
> To: Chen, Junjie J <junjie.j.chen@intel.com>
> Cc: Gonzalez Monroy, Sergio <sergio.gonzalez.monroy@intel.com>; Mcnamara,
> John <john.mcnamara@intel.com>; Tahhan, Maryam
> <maryam.tahhan@intel.com>; Pattan, Reshma <reshma.pattan@intel.com>;
> dev@dpdk.org
> Subject: Re: [dpdk-dev] [PATCH] doc: add a restriction to multi-process support
> 
> On Tue, Nov 28, 2017 at 04:56:54AM -0500, junjie.j.chen@intel.com wrote:
> > From: Junjie Chen <junjie.j.chen@intel.com>
> >
> > This patch add a restriction to multi-process support: secondary
> > processes should only run alongside primary process with same DPDK
> > version, so that secondary processes can use the same hugepage mmap
> > layout as primary process.
> >
> > Signed-off-by: Junjie Chen <junjie.j.chen@intel.com>
> > ---
> >  doc/guides/prog_guide/multi_proc_support.rst | 1 +
> >  doc/guides/tools/proc_info.rst               | 3 ++-
> >  2 files changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/doc/guides/prog_guide/multi_proc_support.rst
> > b/doc/guides/prog_guide/multi_proc_support.rst
> > index 9a9dca7fe..0cd67ae2d 100644
> > --- a/doc/guides/prog_guide/multi_proc_support.rst
> > +++ b/doc/guides/prog_guide/multi_proc_support.rst
> > @@ -51,6 +51,7 @@ For now, there are two types of process specified:
> >  Standalone DPDK processes are primary processes,  while secondary
> > processes can only run alongside a primary process or  after a primary
> > process has already configured the hugepage shared memory for them.
> > +And secondary processes should only run alongside primary process with
> same DPDK version.
> >
> >  To support these two process types, and other multi-process setups
> > described later,  two additional command-line parameters are available to
> the EAL:
> > diff --git a/doc/guides/tools/proc_info.rst
> > b/doc/guides/tools/proc_info.rst index fd17e278c..512fd3263 100644
> > --- a/doc/guides/tools/proc_info.rst
> > +++ b/doc/guides/tools/proc_info.rst
> > @@ -36,7 +36,8 @@ The dpdk-procinfo application is a Data Plane
> > Development Kit (DPDK) application  that runs as a DPDK secondary
> > process and is capable of retrieving port  statistics, resetting port statistics
> and printing DPDK memory information.
> >  This application extends the original functionality that was
> > supported by -dump_cfg.
> > +dump_cfg. Note that dpdk-procinfo can only run alongside primary
> > +process with same DPDK version.
> >
> >  Running the Application
> >  -----------------------
> > --
> Good to add to the docs. I suggest that you add them using the proper "note"
> markup to make it clearer in the docs.

> /Bruce

Thanks, done.

Junjie