linux-kernel - [V6 06/11] powerpc, perf: Re-arrange PMU based branch filter processing in POWER8

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Date:	Wed, 21 May 2014 15:29:51 +0530
From:	Anshuman Khandual <khandual@...ux.vnet.ibm.com>
To:	peterz@...radead.org
Cc:	linux-kernel@...r.kernel.org, mpe@...erman.id.au,
	benh@...nel.crashing.org
Subject: [V6 06/11] powerpc, perf: Re-arrange PMU based branch filter processing in POWER8

This patch does some code re-arrangements to make it clear that
it ignores any separate privilege level branch filter request
and does not support any combinations of HW PMU branch filters.

Signed-off-by: Anshuman Khandual <khandual@...ux.vnet.ibm.com>
---
 arch/powerpc/perf/power8-pmu.c | 21 +++++++--------------
 1 file changed, 7 insertions(+), 14 deletions(-)

diff --git a/arch/powerpc/perf/power8-pmu.c b/arch/powerpc/perf/power8-pmu.c
index fe2763b..13f47f5 100644
--- a/arch/powerpc/perf/power8-pmu.c
+++ b/arch/powerpc/perf/power8-pmu.c
@@ -635,8 +635,6 @@ static int power8_generic_events[] = {
 
 static u64 power8_bhrb_filter_map(u64 branch_sample_type)
 {
-	u64 pmu_bhrb_filter = 0;
-
 	/* BHRB and regular PMU events share the same privilege state
 	 * filter configuration. BHRB is always recorded along with a
 	 * regular PMU event. As the privilege state filter is handled
@@ -644,20 +642,15 @@ static u64 power8_bhrb_filter_map(u64 branch_sample_type)
 	 * PMU event, we ignore any separate BHRB specific request.
 	 */
 
-	/* No branch filter requested */
-	if (branch_sample_type & PERF_SAMPLE_BRANCH_ANY)
-		return pmu_bhrb_filter;
-
-	/* Invalid branch filter options - HW does not support */
-	if (branch_sample_type & PERF_SAMPLE_BRANCH_ANY_RETURN)
-		return -1;
+	/* Ignore user, kernel, hv bits */
+	branch_sample_type &= ~PERF_SAMPLE_BRANCH_PLM_ALL;
 
-	if (branch_sample_type & PERF_SAMPLE_BRANCH_IND_CALL)
-		return -1;
+	/* No branch filter requested */
+	if (branch_sample_type == PERF_SAMPLE_BRANCH_ANY)
+		return 0;
 
-	if (branch_sample_type & PERF_SAMPLE_BRANCH_ANY_CALL) {
-		pmu_bhrb_filter |= POWER8_MMCRA_IFM1;
-		return pmu_bhrb_filter;
+	if (branch_sample_type == PERF_SAMPLE_BRANCH_ANY_CALL) {
+		return POWER8_MMCRA_IFM1;
 	}
 
 	/* Every thing else is unsupported */
-- 
1.7.11.7

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