[PATCH] perf: Fix PMU format parsing test failure

[PATCH] perf: Fix PMU format parsing test failure

[Sukadev Bhattiprolu]

>From 776e6d7942754f139c27753213c9cf4617536618 Mon Sep 17 00:00:00 2001
From: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Date: Thu, 17 Jan 2013 09:11:30 -0800
Subject: [PATCH] perf; 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>
---
 tools/perf/util/include/linux/bitops.h |    1 +
 tools/perf/util/pmu.c                  |    2 +-
 2 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/tools/perf/util/include/linux/bitops.h b/tools/perf/util/include/linux/bitops.h
index a55d8cf..45cf10a 100644
--- a/tools/perf/util/include/linux/bitops.h
+++ b/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));		\
diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index 9bdc60c..b93ff14 100644
--- a/tools/perf/util/pmu.c
+++ b/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);
 }
-- 
1.7.1

Re: [PATCH] perf: Fix PMU format parsing test failure

[Jiri Olsa]

On Thu, Jan 17, 2013 at 09:28:14AM -0800, Sukadev Bhattiprolu wrote:
> 
> From 776e6d7942754f139c27753213c9cf4617536618 Mon Sep 17 00:00:00 2001
> From: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
> Date: Thu, 17 Jan 2013 09:11:30 -0800
> Subject: [PATCH] perf; 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.

indeed.. not sure how the bison 'union' stuff is (z)allocated,
x86 is probably lucky one ;-)

> 
> With this patch, the test passes on POWER and continues to pass on x86.
> 
> Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
> ---
>  tools/perf/util/include/linux/bitops.h |    1 +
>  tools/perf/util/pmu.c                  |    2 +-
>  2 files changed, 2 insertions(+), 1 deletions(-)
> 
> diff --git a/tools/perf/util/include/linux/bitops.h b/tools/perf/util/include/linux/bitops.h
> index a55d8cf..45cf10a 100644
> --- a/tools/perf/util/include/linux/bitops.h
> +++ b/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));		\
> diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
> index 9bdc60c..b93ff14 100644
> --- a/tools/perf/util/pmu.c
> +++ b/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);

oops, nice catch!

Acked-by: Jiri Olsa <jolsa@redhat.com>

thanks,
jirka