Re: Kernelnewbies Digest, Vol 17, Issue 44
Hello guys, I am writing a user space code for pwm controller in beaglebone, but the drivers are in the form of files, so when I am writing the code I got a doubt that, if we keep access the files it may take more processor time so any other way is there to access or this is the best way ? On Thu, Apr 26, 2012 at 9:30 PM, <kernelnewbies-request@kernelnewbies.org>wrote:
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Today's Topics:
1. Re: Profiling my Modules (Daniel Baluta) 2. Re: Linux Driver Project (Bj?rn Mork) 3. Re: Profiling my Modules (Rishi Agrawal) 4. Re: Linux Driver Project (Bj?rn Mork) 5. freelance kernel work (Christopher Harvey)
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Message: 1 Date: Thu, 26 Apr 2012 15:42:57 +0300 From: Daniel Baluta <daniel.baluta@gmail.com> Subject: Re: Profiling my Modules To: Rishi Agrawal <rishi.b.agrawal@gmail.com> Cc: kernelnewbies@kernelnewbies.org Message-ID: <CAEnQRZCf1zjMAQSe8uuYTr7px6-K51fLpB+vwY3SMkDXimcpxw@mail.gmail.com
Content-Type: text/plain; charset=ISO-8859-1
On Thu, Apr 26, 2012 at 10:33 AM, Rishi Agrawal <rishi.b.agrawal@gmail.com> wrote:
Hi All,
I have a kernel module which has functions which take a lot of time in execution. I am curious to know how can I profile it, and find out the functions taking most of the time.
I saw Oprofile, but it seems that I will have to build the whole kernel, and also that it will be difficult to profile my module through it.
Any trick or tool will do.
Hello,
Have a look at perf [1].
thanks, Daniel.
[1] https://perf.wiki.kernel.org/
------------------------------
Message: 2 Date: Thu, 26 Apr 2012 15:16:59 +0200 From: Bj?rn Mork <bjorn@mork.no> Subject: Re: Linux Driver Project To: Rabee Al-Maqabi <rabee.almaqabi@gmail.com> Cc: Javier Martinez Canillas <martinez.javier@gmail.com>, kernelnewbies@kernelnewbies.org Message-ID: <87fwbqeipg.fsf@nemi.mork.no> Content-Type: text/plain; charset=utf-8
Rabee Al-Maqabi <rabee.almaqabi@gmail.com> writes:
Thank you for your reply. Linux Device Drivers is indeed a great book. I have read it in addition to Understanding the Linux Kernel and I have experimented with my Linux box. At this point, I would like to have a real-world experience and write a driver for a piece of hardware not yet supported.
How about a fingerprint scanner? If you've got a modern laptop then chances are good that you already own such a device. And it's most likely unsupported. Some might say that's because it's useless :-)
Otherwise I'd recommend looking through your box of unused devices. No need to go out and buy anything if all you want is to write some driver.
Or see http://www.linuxdriverproject.org/foswiki/bin/view/Main/DriversNeeded if you are open to buying some new device for this project.
You won't find any datasheets or any other documentation, though... Manufacturers smart enough to provide documentation usually get drivers written for their devices in no time. But some still hold it to themselves. Go figure.
Bj?rn
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Message: 3 Date: Thu, 26 Apr 2012 19:01:00 +0530 From: Rishi Agrawal <rishi.b.agrawal@gmail.com> Subject: Re: Profiling my Modules To: Daniel Baluta <daniel.baluta@gmail.com> Cc: kernelnewbies@kernelnewbies.org Message-ID: <CADDndfPtRis6CuXJN7D0v=snCJ8b_hS0eW2cQoBekXE3UtyXSw@mail.gmail.com
Content-Type: text/plain; charset="iso-8859-1"
Thanks a lot, I will have a look at it and see if it helps.
On Thu, Apr 26, 2012 at 6:12 PM, Daniel Baluta <daniel.baluta@gmail.com
wrote:
On Thu, Apr 26, 2012 at 10:33 AM, Rishi Agrawal <rishi.b.agrawal@gmail.com> wrote:
Hi All,
I have a kernel module which has functions which take a lot of time in execution. I am curious to know how can I profile it, and find out the functions taking most of the time.
I saw Oprofile, but it seems that I will have to build the whole kernel, and also that it will be difficult to profile my module through it.
Any trick or tool will do.
Hello,
Have a look at perf [1].
thanks, Daniel.
-- Regards, Rishi Agrawal
Hi Jeshwanth, On Thu, Apr 26, 2012 at 11:10 PM, Jeshwanth Kumar N K Jeshu <jeshkumar555@gmail.com> wrote:
Hello guys, I am writing a user space code for pwm controller in beaglebone, but the drivers are in the form of files, so when I am writing the code I got a doubt that, if we keep access the files it may take more processor time so any other way is there to access or this is the best way ?
Can you be more clear here. Are you talking about source code? Arun
On Thu, Apr 26, 2012 at 9:30 PM, <kernelnewbies-request@kernelnewbies.org> wrote:
Send Kernelnewbies mailing list submissions to kernelnewbies@kernelnewbies.org
To subscribe or unsubscribe via the World Wide Web, visit http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies or, via email, send a message with subject or body 'help' to kernelnewbies-request@kernelnewbies.org
You can reach the person managing the list at kernelnewbies-owner@kernelnewbies.org
When replying, please edit your Subject line so it is more specific than "Re: Contents of Kernelnewbies digest..."
Today's Topics:
1. Re: Profiling my Modules (Daniel Baluta) 2. Re: Linux Driver Project (Bj?rn Mork) 3. Re: Profiling my Modules (Rishi Agrawal) 4. Re: Linux Driver Project (Bj?rn Mork) 5. freelance kernel work (Christopher Harvey)
----------------------------------------------------------------------
Message: 1 Date: Thu, 26 Apr 2012 15:42:57 +0300 From: Daniel Baluta <daniel.baluta@gmail.com> Subject: Re: Profiling my Modules To: Rishi Agrawal <rishi.b.agrawal@gmail.com> Cc: kernelnewbies@kernelnewbies.org Message-ID:
<CAEnQRZCf1zjMAQSe8uuYTr7px6-K51fLpB+vwY3SMkDXimcpxw@mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1
On Thu, Apr 26, 2012 at 10:33 AM, Rishi Agrawal <rishi.b.agrawal@gmail.com> wrote:
Hi All,
I have a kernel module which has functions which take a lot of time in execution. I am curious to know how can I profile it, and find out the functions taking most of the time.
I saw Oprofile, but it seems that I will have to build the whole kernel, and also that it will be difficult to profile my module through it.
Any trick or tool will do.
Hello,
Have a look at perf [1].
thanks, Daniel.
[1] https://perf.wiki.kernel.org/
------------------------------
Message: 2 Date: Thu, 26 Apr 2012 15:16:59 +0200 From: Bj?rn Mork <bjorn@mork.no> Subject: Re: Linux Driver Project To: Rabee Al-Maqabi <rabee.almaqabi@gmail.com> Cc: Javier Martinez Canillas <martinez.javier@gmail.com>, kernelnewbies@kernelnewbies.org Message-ID: <87fwbqeipg.fsf@nemi.mork.no> Content-Type: text/plain; charset=utf-8
Rabee Al-Maqabi <rabee.almaqabi@gmail.com> writes:
Thank you for your reply. Linux Device Drivers is indeed a great book. I have read it in addition to Understanding the Linux Kernel and I have experimented with my Linux box. At this point, I would like to have a real-world experience and write a driver for a piece of hardware not yet supported.
How about a fingerprint scanner? If you've got a modern laptop then chances are good that you already own such a device. And it's most likely unsupported. Some might say that's because it's useless :-)
Otherwise I'd recommend looking through your box of unused devices. No need to go out and buy anything if all you want is to write some driver.
Or see http://www.linuxdriverproject.org/foswiki/bin/view/Main/DriversNeeded if you are open to buying some new device for this project.
You won't find any datasheets or any other documentation, though... Manufacturers smart enough to provide documentation usually get drivers written for their devices in no time. But some still hold it to themselves. Go figure.
Bj?rn
------------------------------
Message: 3 Date: Thu, 26 Apr 2012 19:01:00 +0530 From: Rishi Agrawal <rishi.b.agrawal@gmail.com> Subject: Re: Profiling my Modules To: Daniel Baluta <daniel.baluta@gmail.com> Cc: kernelnewbies@kernelnewbies.org Message-ID:
<CADDndfPtRis6CuXJN7D0v=snCJ8b_hS0eW2cQoBekXE3UtyXSw@mail.gmail.com> Content-Type: text/plain; charset="iso-8859-1"
Thanks a lot, I will have a look at it and see if it helps.
On Thu, Apr 26, 2012 at 6:12 PM, Daniel Baluta <daniel.baluta@gmail.com>wrote:
On Thu, Apr 26, 2012 at 10:33 AM, Rishi Agrawal <rishi.b.agrawal@gmail.com> wrote:
Hi All,
I have a kernel module which has functions which take a lot of time in execution. I am curious to know how can I profile it, and find out the functions taking most of the time.
I saw Oprofile, but it seems that I will have to build the whole kernel, and also that it will be difficult to profile my module through it.
Any trick or tool will do.
Hello,
Have a look at perf [1].
thanks, Daniel.
-- Regards, Rishi Agrawal
participants (2)
-
Arun KS -
Jeshwanth Kumar N K Jeshu