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Diffstat (limited to 'arch/x86/oprofile/op_model_amd.c')
-rw-r--r--arch/x86/oprofile/op_model_amd.c80
1 files changed, 63 insertions, 17 deletions
diff --git a/arch/x86/oprofile/op_model_amd.c b/arch/x86/oprofile/op_model_amd.c
index 4eb30715b1d5..6557683c190e 100644
--- a/arch/x86/oprofile/op_model_amd.c
+++ b/arch/x86/oprofile/op_model_amd.c
@@ -23,6 +23,8 @@
#include <asm/msr.h>
#include <asm/nmi.h>
#include <asm/apic.h>
+#include <asm/processor.h>
+#include <asm/cpufeature.h>
#include "op_x86_model.h"
#include "op_counter.h"
@@ -58,7 +60,7 @@ static unsigned long reset_value[NUM_VIRT_COUNTERS];
#define IBS_FETCH_SIZE 6
#define IBS_OP_SIZE 12
-static int has_ibs; /* AMD Family10h and later */
+static u32 ibs_caps;
struct op_ibs_config {
unsigned long op_enabled;
@@ -71,6 +73,40 @@ struct op_ibs_config {
static struct op_ibs_config ibs_config;
+/*
+ * IBS cpuid feature detection
+ */
+
+#define IBS_CPUID_FEATURES 0x8000001b
+
+/*
+ * 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_OPCNT (1LL<<4)
+
+static u32 get_ibs_caps(void)
+{
+ u32 ibs_caps;
+ unsigned int max_level;
+
+ if (!boot_cpu_has(X86_FEATURE_IBS))
+ return 0;
+
+ /* check IBS cpuid feature flags */
+ max_level = cpuid_eax(0x80000000);
+ if (max_level < IBS_CPUID_FEATURES)
+ return IBS_CAPS_AVAIL;
+
+ ibs_caps = cpuid_eax(IBS_CPUID_FEATURES);
+ if (!(ibs_caps & IBS_CAPS_AVAIL))
+ /* cpuid flags not valid */
+ return IBS_CAPS_AVAIL;
+
+ return ibs_caps;
+}
+
#ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
static void op_mux_fill_in_addresses(struct op_msrs * const msrs)
@@ -189,7 +225,7 @@ op_amd_handle_ibs(struct pt_regs * const regs,
u64 val, ctl;
struct op_entry entry;
- if (!has_ibs)
+ if (!ibs_caps)
return;
if (ibs_config.fetch_enabled) {
@@ -241,16 +277,21 @@ op_amd_handle_ibs(struct pt_regs * const regs,
static inline void op_amd_start_ibs(void)
{
u64 val;
- if (has_ibs && ibs_config.fetch_enabled) {
+
+ if (!ibs_caps)
+ return;
+
+ if (ibs_config.fetch_enabled) {
val = (ibs_config.max_cnt_fetch >> 4) & 0xFFFF;
val |= ibs_config.rand_en ? IBS_FETCH_RAND_EN : 0;
val |= IBS_FETCH_ENABLE;
wrmsrl(MSR_AMD64_IBSFETCHCTL, val);
}
- if (has_ibs && ibs_config.op_enabled) {
+ if (ibs_config.op_enabled) {
val = (ibs_config.max_cnt_op >> 4) & 0xFFFF;
- val |= ibs_config.dispatched_ops ? IBS_OP_CNT_CTL : 0;
+ if (ibs_caps & IBS_CAPS_OPCNT && ibs_config.dispatched_ops)
+ val |= IBS_OP_CNT_CTL;
val |= IBS_OP_ENABLE;
wrmsrl(MSR_AMD64_IBSOPCTL, val);
}
@@ -258,11 +299,14 @@ static inline void op_amd_start_ibs(void)
static void op_amd_stop_ibs(void)
{
- if (has_ibs && ibs_config.fetch_enabled)
+ if (!ibs_caps)
+ return;
+
+ if (ibs_config.fetch_enabled)
/* clear max count and enable */
wrmsrl(MSR_AMD64_IBSFETCHCTL, 0);
- if (has_ibs && ibs_config.op_enabled)
+ if (ibs_config.op_enabled)
/* clear max count and enable */
wrmsrl(MSR_AMD64_IBSOPCTL, 0);
}
@@ -395,29 +439,30 @@ static int init_ibs_nmi(void)
/* uninitialize the APIC for the IBS interrupts if needed */
static void clear_ibs_nmi(void)
{
- if (has_ibs)
+ if (ibs_caps)
on_each_cpu(apic_clear_ibs_nmi_per_cpu, NULL, 1);
}
/* initialize the APIC for the IBS interrupts if available */
static void ibs_init(void)
{
- has_ibs = boot_cpu_has(X86_FEATURE_IBS);
+ ibs_caps = get_ibs_caps();
- if (!has_ibs)
+ if (!ibs_caps)
return;
if (init_ibs_nmi()) {
- has_ibs = 0;
+ ibs_caps = 0;
return;
}
- printk(KERN_INFO "oprofile: AMD IBS detected\n");
+ printk(KERN_INFO "oprofile: AMD IBS detected (0x%08x)\n",
+ (unsigned)ibs_caps);
}
static void ibs_exit(void)
{
- if (!has_ibs)
+ if (!ibs_caps)
return;
clear_ibs_nmi();
@@ -437,7 +482,7 @@ static int setup_ibs_files(struct super_block *sb, struct dentry *root)
if (ret)
return ret;
- if (!has_ibs)
+ if (!ibs_caps)
return ret;
/* model specific files */
@@ -447,7 +492,7 @@ static int setup_ibs_files(struct super_block *sb, struct dentry *root)
ibs_config.fetch_enabled = 0;
ibs_config.max_cnt_op = 250000;
ibs_config.op_enabled = 0;
- ibs_config.dispatched_ops = 1;
+ ibs_config.dispatched_ops = 0;
dir = oprofilefs_mkdir(sb, root, "ibs_fetch");
oprofilefs_create_ulong(sb, dir, "enable",
@@ -462,8 +507,9 @@ static int setup_ibs_files(struct super_block *sb, struct dentry *root)
&ibs_config.op_enabled);
oprofilefs_create_ulong(sb, dir, "max_count",
&ibs_config.max_cnt_op);
- oprofilefs_create_ulong(sb, dir, "dispatched_ops",
- &ibs_config.dispatched_ops);
+ if (ibs_caps & IBS_CAPS_OPCNT)
+ oprofilefs_create_ulong(sb, dir, "dispatched_ops",
+ &ibs_config.dispatched_ops);
return 0;
}