This is the mail archive of the
systemtap@sourceware.org
mailing list for the systemtap project.
Re: [RFC][PATCH -tip 4/9] power: add kernel_trap_sp()
- From: Masami Hiramatsu <mhiramat at redhat dot com>
- To: ananth at in dot ibm dot com
- Cc: Benjamin Herrenschmidt <benh at kernel dot crashing dot org>, Ingo Molnar <mingo at elte dot hu>, linuxppc-dev at ozlabs dot org, systemtap-ml <systemtap at sources dot redhat dot com>, Steven Rostedt <rostedt at goodmis dot org>, LKML <linux-kernel at vger dot kernel dot org>
- Date: Fri, 20 Mar 2009 06:53:43 -0400
- Subject: Re: [RFC][PATCH -tip 4/9] power: add kernel_trap_sp()
- References: <49C2B4BF.4080904@redhat.com> <1237527760.25062.567.camel@pasglop> <20090320073334.GA10519@in.ibm.com>
Ananth N Mavinakayanahalli wrote:
> On Fri, Mar 20, 2009 at 04:42:40PM +1100, Benjamin Herrenschmidt wrote:
>> On Thu, 2009-03-19 at 17:10 -0400, Masami Hiramatsu wrote:
>>> Add kernel_trap_sp() on powerpc, based on systemtap's runtime/regs.h.
>>>
>>> Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
>> I haven't looked at the usage of it, but it's weird to have something
>> call "kernel_trap_sp" that returns the -user- stack pointer... is
>> this really what's expected here ?
>
> In the current usage scenario, this gets called only with a pt_regs
> snapshot from in kernel. user_stack_pointer() is a misnomer though;
> all this macro needs is to return the stack pointer from the given
> pt_regs.
Indeed,
I expect kernel_trap_sp() returns the top of stack from pt_regs in the kernel.
Why I'm using user_stack_pointer() for kernel_trap_sp() is just that the
definitions of both are same...
Perhaps, should I define as below, even it is same as user_stack_pointer()?
#define kernel_trap_sp(regs) ((regs)->gpr[1])
Thank you,
>
> Ananth
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
--
Masami Hiramatsu
Software Engineer
Hitachi Computer Products (America) Inc.
Software Solutions Division
e-mail: mhiramat@redhat.com