perf tools: Fix PMU format parsing test failure

On POWER, the 'perf format parsing' test always fails.

Looks like it is because memset() is being passed number of longs rather
than number of bytes. It is interesting that the test always passes on
my x86 box.

With this patch, the test passes on POWER and continues to pass on x86.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Anton Blanchard <anton@au1.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@ozlabs.org
Link: http://lkml.kernel.org/r/20130117172814.GA18882@us.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/include/linux/bitops.h

@@ -14,6 +14,7 @@
 #define BITS_TO_LONGS(nr)       DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))
 #define BITS_TO_U64(nr)         DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(u64))
 #define BITS_TO_U32(nr)         DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(u32))
+#define BITS_TO_BYTES(nr)       DIV_ROUND_UP(nr, BITS_PER_BYTE)
 
 #define for_each_set_bit(bit, addr, size) \
 	for ((bit) = find_first_bit((addr), (size));		\

tools/perf/util/pmu.c

@@ -548,7 +548,7 @@ void perf_pmu__set_format(unsigned long *bits, long from, long to)
 	if (!to)
 		to = from;
 
-	memset(bits, 0, BITS_TO_LONGS(PERF_PMU_FORMAT_BITS));
+	memset(bits, 0, BITS_TO_BYTES(PERF_PMU_FORMAT_BITS));
 	for (b = from; b <= to; b++)
 		set_bit(b, bits);
 }