[PATCH 1/1] perf tools: fix format max value calculation

[PATCH 1/1] perf tools: fix format max value calculation

[kan.liang]

From: Kan Liang <kan.liang@intel.com>

Currently the max value of format is calculated by the bits number. It
relies on the continuity of the format.
However, uncore event format is not continuous. E.g. uncore qpi event
format can be 0-7,21.
If bit 21 is set, there is parsing issues as below.
perf stat -a -e uncore_qpi_0/event=0x200002,umask=0x8/
event syntax error: '..pi_0/event=0x200002,umask=0x8/'
                                  \___ value too big for format, maximum
is 511

This patch return the real max value by setting all possible bit to 1.

Signed-off-by: Kan Liang <kan.liang@intel.com>
---
 tools/perf/util/pmu.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index adef23b..bf34468 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -602,14 +602,13 @@ static void pmu_format_value(unsigned long *format, __u64 value, __u64 *v,
 
 static __u64 pmu_format_max_value(const unsigned long *format)
 {
-	int w;
+	__u64 w = 0;
+	int fbit;
 
-	w = bitmap_weight(format, PERF_PMU_FORMAT_BITS);
-	if (!w)
-		return 0;
-	if (w < 64)
-		return (1ULL << w) - 1;
-	return -1;
+	for_each_set_bit(fbit, format, PERF_PMU_FORMAT_BITS)
+		w |= (1ULL << fbit);
+
+	return w;
 }
 
 /*
-- 
2.5.0

Re: [PATCH 1/1] perf tools: fix format max value calculation

[Arnaldo Carvalho de Melo]

Em Wed, Mar 30, 2016 at 12:16:15PM -0700, kan.liang@intel.com escreveu:
> From: Kan Liang <kan.liang@intel.com>
> 
> Currently the max value of format is calculated by the bits number. It
> relies on the continuity of the format.
> However, uncore event format is not continuous. E.g. uncore qpi event
> format can be 0-7,21.
> If bit 21 is set, there is parsing issues as below.
> perf stat -a -e uncore_qpi_0/event=0x200002,umask=0x8/
> event syntax error: '..pi_0/event=0x200002,umask=0x8/'
>                                   \___ value too big for format, maximum
> is 511
> 
> This patch return the real max value by setting all possible bit to 1.

Looks good, applied.

- Arnaldo

[tip:perf/core] perf tools: Fix PMU term format max value calculation

[tip-bot for Kan Liang]

Commit-ID:  ac0e2cd555373ae6f8f3a3ad3fbbf5b6d1e7aaaa
Gitweb:     http://git.kernel.org/tip/ac0e2cd555373ae6f8f3a3ad3fbbf5b6d1e7aaaa
Author:     Kan Liang <kan.liang@intel.com>
AuthorDate: Wed, 30 Mar 2016 12:16:15 -0700
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Fri, 1 Apr 2016 18:46:24 -0300

perf tools: Fix PMU term format max value calculation

Currently the max value of format is calculated by the bits number. It
relies on the continuity of the format.

However, uncore event format is not continuous. E.g. uncore qpi event
format can be 0-7,21.

If bit 21 is set, there is parsing issues as below.

  $ perf stat -a -e uncore_qpi_0/event=0x200002,umask=0x8/
  event syntax error: '..pi_0/event=0x200002,umask=0x8/'
                                    \___ value too big for format, maximum is 511

This patch return the real max value by setting all possible bits to 1.

Signed-off-by: Kan Liang <kan.liang@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1459365375-14285-1-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/pmu.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index adef23b..bf34468 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -602,14 +602,13 @@ static void pmu_format_value(unsigned long *format, __u64 value, __u64 *v,
 
 static __u64 pmu_format_max_value(const unsigned long *format)
 {
-	int w;
+	__u64 w = 0;
+	int fbit;
 
-	w = bitmap_weight(format, PERF_PMU_FORMAT_BITS);
-	if (!w)
-		return 0;
-	if (w < 64)
-		return (1ULL << w) - 1;
-	return -1;
+	for_each_set_bit(fbit, format, PERF_PMU_FORMAT_BITS)
+		w |= (1ULL << fbit);
+
+	return w;
 }
 
 /*