From: j.neuschaefer@gmx.net (Jonathan Neuschäfer)
To: kernelnewbies@lists.kernelnewbies.org
Subject: is memcpy a system call?
Date: Fri, 8 Jun 2012 23:48:15 +0200 [thread overview]
Message-ID: <20120608214815.GA2711@debian.debian> (raw)
In-Reply-To: <4FD21628.1050800@gmail.com>
On Sat, Jun 09, 2012 at 12:11:36AM +0900, J.Hwan Kim wrote:
> Hi, everyone
>
> Is memcpy a system call?
>
> Thanks in advnace,
>
> Best Regards,
> J.Hwna Kim
"strace" is a good tool to find out which system calls a program is
doing.
To answer your question, I don't think it makes much sense to implement
memcpy as a syscall, because entering kernel mode is usually relatively
expensive and I can't think of any kernel mode-only memcpy optimizations
(and optimizations are the only reason to do a user space memcpy in
kernel space I can think of).
HTH,
Jonathan Neusch?fer
next prev parent reply other threads:[~2012-06-08 21:48 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-06-08 15:11 is memcpy a system call? J.Hwan Kim
2012-06-08 15:18 ` rahul dev
2012-06-08 15:21 ` siddharth saxena
2012-06-08 21:49 ` Jonathan Neuschäfer
2012-06-12 10:17 ` Bernd Petrovitsch
2012-06-08 21:48 ` Jonathan Neuschäfer [this message]
2012-06-08 22:32 ` Ezequiel Garcia
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