[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20131125093359.GB3161@krava.brq.redhat.com>
Date: Mon, 25 Nov 2013 10:33:59 +0100
From: Jiri Olsa <jolsa@...hat.com>
To: Namhyung Kim <namhyung@...nel.org>
Cc: Steven Rostedt <rostedt@...dmis.org>, linux-kernel@...r.kernel.org,
Corey Ashford <cjashfor@...ux.vnet.ibm.com>,
Frederic Weisbecker <fweisbec@...il.com>,
Ingo Molnar <mingo@...e.hu>, Paul Mackerras <paulus@...ba.org>,
Peter Zijlstra <a.p.zijlstra@...llo.nl>,
Arnaldo Carvalho de Melo <acme@...hat.com>,
David Ahern <dsahern@...il.com>
Subject: Re: [PATCH 03/22] tools lib traceevent: Add
traceevent_host_bigendian function
On Mon, Nov 25, 2013 at 04:24:52PM +0900, Namhyung Kim wrote:
> Hi Steve,
>
> On Sat, 23 Nov 2013 03:27:08 -0500, Steven Rostedt wrote:
> > On Fri, 22 Nov 2013 23:22:52 +0900
> > Namhyung Kim <namhyung@...nel.org> wrote:
> >
> >> 2013-11-21 (목), 12:01 +0100, Jiri Olsa:
> >> > Adding traceevent_host_bigendian function to get host
> >> > endianity. It's used in following patches.
> >>
> >> [SNIP]
> >> > +static inline int traceevent_host_bigendian(void)
> >> > +{
> >> > + unsigned char str[] = { 0x1, 0x2, 0x3, 0x4 };
> >> > + unsigned int *ptr;
> >> > +
> >> > + ptr = (unsigned int *)str;
> >> > + return *ptr == 0x01020304;
> >>
> >> Is it safe for every architecture supported - especially ones that
> >> require stricter alignment? I know many architectures/compilers align
> >> stack but not sure doing this is safe for all architecture.
> >
> > Would you prefer this (I tested it on both a big and little endian)
> >
> > {
> > unsigned char str[] = { 0x1, 0x2, 0x3, 0x4 };
> > unsigned int val;
> >
> > memcpy(&val, str, 4);
> > return val == 0x01020304;
> > }
>
> Yeah, looks good to me.
ok, will change to this one
thanks,
jirka
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists