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To: Jan Kratochvil <jan.kratochvil@redhat.com>
Cc: Eli Zaretskii <eliz@gnu.org>, robertsong.japan@gmail.com,        gdb@sourceware.org
Subject: Re: Why no hwatch command in gdb ?
References: <AANLkTimsE5nNEZ=EKo1wPs0BW9dNxdvVyu_5Fucts5K8@mail.gmail.com>	<20110310081154.GA13603@host1.jankratochvil.net>	<AANLkTi=5n0EebJQkWvXvCHnVxy5fEqrxSztdDhhcpCNR@mail.gmail.com>	<20110310103409.GA29242@host1.jankratochvil.net>	<E1Pxe0v-000453-AA@fencepost.gnu.org>	<20110310115543.GA5414@host1.jankratochvil.net>
From: fche@redhat.com (Frank Ch. Eigler)
Date: Thu, 10 Mar 2011 14:47:00 -0000
In-Reply-To: <20110310115543.GA5414@host1.jankratochvil.net> (Jan Kratochvil's message of "Thu, 10 Mar 2011 12:55:43 +0100")
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Jan Kratochvil <jan.kratochvil@redhat.com> writes:

> [...]
> But it being discussed for upstream kernel that the DR registers access via
> PTRACE_POKEUSER is broken anyway and GDB should use the existing hardware
> watchpoints support in Linux kernel perf via some higher level interface
> (still probably through the ptrace syscall).

While a new kernel interface wouldn't be able to fabricate any
hardware-watchpoint resources after they're exhausted, a properly
designed one should be able to evaluate software watchpoints much
faster.

- FChE