From mboxrd@z Thu Jan  1 00:00:00 1970
From: me@tobin.cc (Tobin C. Harding)
Date: Mon, 12 Feb 2018 11:25:05 +1100
Subject: Query on mechanisms to communicate between kernel modules in Linux
In-Reply-To: <CAODjBtr=bEkrN_DNY6jhXTxx0dg=nW-qzBb7WKkZhtSF=_Ezhg@mail.gmail.com>
References: <CAODjBtrCPAyReM-sYcvPAzJWz_Pxa_CCcb9+auoooGAmd3v1MA@mail.gmail.com>
 <20180208142618.GA18803@kroah.com>
 <CAODjBtr8q8SO6Tmp7r55eKsPyEtc1rM8CKhC0Xn4b_enMgpdgg@mail.gmail.com>
 <33841.1518117625@turing-police.cc.vt.edu>
 <CAODjBtrn3Q=TvzthJxq9OKgBbdW27ihyr8XmBK4qxfEzXzBR5g@mail.gmail.com>
 <CAOuPNLj7WoYVoM=geZmmHzS=Ru9bR8LVsuTCgC+ALGOj4venGw@mail.gmail.com>
 <CAODjBtr=bEkrN_DNY6jhXTxx0dg=nW-qzBb7WKkZhtSF=_Ezhg@mail.gmail.com>
Message-ID: <20180212002505.GA16552@eros>
To: kernelnewbies@lists.kernelnewbies.org
List-Id: kernelnewbies.lists.kernelnewbies.org

On Sat, Feb 10, 2018 at 10:30:36PM +0530, Neil Thomas wrote:
> Thanks a lot. I will try out this.

Please don't top post.  It upsets people.

Good luck,
Tobin.

> On 10-Feb-2018 2:08 PM, "Pintu Kumar" <pintu.ping@gmail.com> wrote:
> 
> > On Fri, Feb 9, 2018 at 12:52 AM, Neil Thomas <neilkt27@gmail.com> wrote:
> > > Thanks, I will check it out.
> > >
> > > On 09-Feb-2018 12:50 AM, <valdis.kletnieks@vt.edu> wrote:
> > >>
> > >> On Thu, 08 Feb 2018 23:38:01 +0530, Neil Thomas said:
> > >>
> > >> > I am just a beginner. I have tried procfs, Netlink socket to
> > communicate
> > >> > between user space and kernel space and it works fine.
> > >> >
> > >> > I am developing a monitoring utility to trace the VFS operation and
> > find
> > >> > the frequency of VFS function calls. This monitoring utility runs in
> > >> > kernel
> > >> > space. We have to record the occurrence of each  VFS function calls
> > >> > (like
> > >> > vfs_open(), vfs_read()).  I don't know  which is best mechanism to
> > >> > report
> > >> > this VFS event to the monitoring utility.
> > >> >
> > >> > Could anyone please suggest the best mechanism to transfer data
> > >> > frequently
> > >> > between kernel modules.
> >
> > You can also use ION (CONFIG_ION) or DMABUF (DMA_SHARED_BUFFER) buffer
> > sharing mechanism to share data between 2 drivers.
> > Check this:
> > https://www.kernel.org/doc/html/latest/driver-api/dma-buf.html
> > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/
> > linux.git/tree/drivers/staging/android/ion?h=v4.15
> >
> > >>
> > >> There's a perfectly good perf-based function trace facility that will
> > >> provide
> > >> this info to userspace.
> > >>
> > >> http://www.brendangregg.com/perf.html#StaticKernelTracing
> > >>
> > >
> > > _______________________________________________
> > > Kernelnewbies mailing list
> > > Kernelnewbies at kernelnewbies.org
> > > https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
> > >
> >

> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies at kernelnewbies.org
> https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies