[PATCH 3/7] oprofile, x86: Check IBS capability bits 1 and 2

[Robert Richter]

There are IBS CPUID feature flags in CPUID Fn8000_001B to detect if
the cpu supports IBS fetch sampling (FetchSam) and/or IBS execution
sampling (OpSam). This patch adds checks if the both features are
available.

Spec:

 http://support.amd.com/us/Processor_TechDocs/31116.pdf

Signed-off-by: Robert Richter <robert.richter@xxxxxxx>
---
 arch/x86/oprofile/op_model_amd.c |   59 ++++++++++++++++++++++++-------------
 1 files changed, 38 insertions(+), 21 deletions(-)

diff --git a/arch/x86/oprofile/op_model_amd.c b/arch/x86/oprofile/op_model_amd.c
index b67a6b5..96852d5 100644
--- a/arch/x86/oprofile/op_model_amd.c
+++ b/arch/x86/oprofile/op_model_amd.c
@@ -70,9 +70,22 @@ static u64 ibs_op_ctl;
  * Same bit mask as for IBS cpuid feature flags (Fn8000_001B_EAX), but
  * bit 0 is used to indicate the existence of IBS.
  */
-#define IBS_CAPS_AVAIL			(1LL<<0)
-#define IBS_CAPS_RDWROPCNT		(1LL<<3)
-#define IBS_CAPS_OPCNT			(1LL<<4)
+#define IBS_CAPS_AVAIL			(1U<<0)
+#define IBS_CAPS_FETCHSAM		(1U<<1)
+#define IBS_CAPS_OPSAM			(1U<<2)
+#define IBS_CAPS_RDWROPCNT		(1U<<3)
+#define IBS_CAPS_OPCNT			(1U<<4)
+
+#define IBS_CAPS_DEFAULT		(IBS_CAPS_AVAIL		\
+					 | IBS_CAPS_FETCHSAM	\
+					 | IBS_CAPS_OPSAM)
+
+/*
+ * IBS APIC setup
+ */
+#define IBSCTL				0x1cc
+#define IBSCTL_LVT_OFFSET_VALID		(1ULL<<8)
+#define IBSCTL_LVT_OFFSET_MASK		0x0F
 
 /*
  * IBS randomization macros
@@ -92,12 +105,12 @@ static u32 get_ibs_caps(void)
 	/* check IBS cpuid feature flags */
 	max_level = cpuid_eax(0x80000000);
 	if (max_level < IBS_CPUID_FEATURES)
-		return IBS_CAPS_AVAIL;
+		return IBS_CAPS_DEFAULT;
 
 	ibs_caps = cpuid_eax(IBS_CPUID_FEATURES);
 	if (!(ibs_caps & IBS_CAPS_AVAIL))
 		/* cpuid flags not valid */
-		return IBS_CAPS_AVAIL;
+		return IBS_CAPS_DEFAULT;
 
 	return ibs_caps;
 }
@@ -527,22 +540,26 @@ static int setup_ibs_files(struct super_block *sb, struct dentry *root)
 	ibs_config.op_enabled = 0;
 	ibs_config.dispatched_ops = 0;
 
-	dir = oprofilefs_mkdir(sb, root, "ibs_fetch");
-	oprofilefs_create_ulong(sb, dir, "enable",
-				&ibs_config.fetch_enabled);
-	oprofilefs_create_ulong(sb, dir, "max_count",
-				&ibs_config.max_cnt_fetch);
-	oprofilefs_create_ulong(sb, dir, "rand_enable",
-				&ibs_config.rand_en);
-
-	dir = oprofilefs_mkdir(sb, root, "ibs_op");
-	oprofilefs_create_ulong(sb, dir, "enable",
-				&ibs_config.op_enabled);
-	oprofilefs_create_ulong(sb, dir, "max_count",
-				&ibs_config.max_cnt_op);
-	if (ibs_caps & IBS_CAPS_OPCNT)
-		oprofilefs_create_ulong(sb, dir, "dispatched_ops",
-					&ibs_config.dispatched_ops);
+	if (ibs_caps & IBS_CAPS_FETCHSAM) {
+		dir = oprofilefs_mkdir(sb, root, "ibs_fetch");
+		oprofilefs_create_ulong(sb, dir, "enable",
+					&ibs_config.fetch_enabled);
+		oprofilefs_create_ulong(sb, dir, "max_count",
+					&ibs_config.max_cnt_fetch);
+		oprofilefs_create_ulong(sb, dir, "rand_enable",
+					&ibs_config.rand_en);
+	}
+
+	if (ibs_caps & IBS_CAPS_OPSAM) {
+		dir = oprofilefs_mkdir(sb, root, "ibs_op");
+		oprofilefs_create_ulong(sb, dir, "enable",
+					&ibs_config.op_enabled);
+		oprofilefs_create_ulong(sb, dir, "max_count",
+					&ibs_config.max_cnt_op);
+		if (ibs_caps & IBS_CAPS_OPCNT)
+			oprofilefs_create_ulong(sb, dir, "dispatched_ops",
+						&ibs_config.dispatched_ops);
+	}
 
 	return 0;
 }
-- 
1.7.2.2


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