From: David Ahern <dsahern@gmail.com>
To: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org,
mingo@elte.hu, peterz@infradead.org, fweisbec@gmail.com,
paulus@samba.org, tglx@linutronix.de, anton@samba.org
Subject: Re: [PATCH] perf tool: fix endianness handling of u32 data in samples
Date: Fri, 02 Sep 2011 14:06:08 -0600 [thread overview]
Message-ID: <4E613730.4080508@gmail.com> (raw)
In-Reply-To: <20110902200255.GG17970@ghostprotocols.net>
On 09/02/2011 02:02 PM, Arnaldo Carvalho de Melo wrote:
> Em Fri, Sep 02, 2011 at 01:41:51PM -0600, David Ahern escreveu:
>> @@ -423,18 +449,25 @@ int perf_event__parse_sample(const union perf_event *event, u64 type,
>> }
>>
>> if (type & PERF_SAMPLE_RAW) {
>> - u32 *p = (u32 *)array;
>> + u.val64 = *array;
>> + if (swapped) {
>> + /* undo swap of u64, then swap on individual u32s */
>> + u.val64 = bswap_64(u.val64);
>> + u.val32[0] = bswap_32(u.val32[0]);
>> + u.val32[1] = bswap_32(u.val32[1]);
>> +
>> + WARN_ONCE(swapped, "Endianness of raw data not corrected!\n");
>> + }
>
> That works too, but then we'll be always testing swapped two times :-)
>
> - Arnaldo
I did not see a WARN_ONCE with no 'condition' variable, so I went with
the redundant test. I guess swapped really could be changed to '1' --
like an example I saw in the acpi code.
David
next prev parent reply other threads:[~2011-09-02 20:06 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-02 19:41 [PATCH] perf tool: fix endianness handling of u32 data in samples David Ahern
2011-09-02 20:02 ` Arnaldo Carvalho de Melo
2011-09-02 20:06 ` David Ahern [this message]
-- strict thread matches above, loose matches on Subject: below --
2011-08-29 21:55 David Ahern
2011-09-01 16:19 ` Arnaldo Carvalho de Melo
2011-09-01 16:41 ` David Ahern
2011-09-01 16:54 ` David Ahern
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