[PATCH 22/24] x86/oprofile: Add CONFIG_OPROFILE_IBS option

From: Robert Richter
Date: Tue Jul 22 2008 - 15:26:30 EST


Signed-off-by: Robert Richter <robert.richter@xxxxxxx>
---
arch/Kconfig | 14 ++++++++++++++
arch/x86/oprofile/op_model_athlon.c | 33 +++++++++++++++++++++++----------
drivers/oprofile/buffer_sync.c | 6 ++++++
drivers/oprofile/cpu_buffer.c | 4 ++++
4 files changed, 47 insertions(+), 10 deletions(-)

diff --git a/arch/Kconfig b/arch/Kconfig
index ad89a33..62be4e2 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -13,6 +13,20 @@ config OPROFILE

If unsure, say N.

+config OPROFILE_IBS
+ bool "OProfile AMD IBS support (EXPERIMENTAL)"
+ default n
+ depends on OPROFILE && SMP && X86
+ help
+ Instruction-Based Sampling (IBS) is a new profiling
+ technique that provides rich, precise program performance
+ information. IBS is introduced by AMD Family10h processors
+ (AMD Opteron Quad-Core processor â??Barcelonaâ??) to overcome
+ the limitations of conventional performance counter
+ sampling.
+
+ If unsure, say N.
+
config HAVE_OPROFILE
def_bool n

diff --git a/arch/x86/oprofile/op_model_athlon.c b/arch/x86/oprofile/op_model_athlon.c
index 9c8c8c5..fb6015c 100644
--- a/arch/x86/oprofile/op_model_athlon.c
+++ b/arch/x86/oprofile/op_model_athlon.c
@@ -47,6 +47,10 @@
#define CTRL_SET_HOST_ONLY(val, h) (val |= ((h & 1) << 9))
#define CTRL_SET_GUEST_ONLY(val, h) (val |= ((h & 1) << 8))

+static unsigned long reset_value[NUM_COUNTERS];
+
+#ifdef CONFIG_OPROFILE_IBS
+
/* IbsFetchCtl bits/masks */
#define IBS_FETCH_HIGH_VALID_BIT (1UL << 17) /* bit 49 */
#define IBS_FETCH_HIGH_ENABLE (1UL << 16) /* bit 48 */
@@ -104,7 +108,6 @@ struct ibs_op_sample {
*/
static void clear_ibs_nmi(void);

-static unsigned long reset_value[NUM_COUNTERS];
static int ibs_allowed; /* AMD Family10h and later */

struct op_ibs_config {
@@ -118,6 +121,8 @@ struct op_ibs_config {

static struct op_ibs_config ibs_config;

+#endif
+
/* functions for op_amd_spec */

static void op_amd_fill_in_addresses(struct op_msrs * const msrs)
@@ -188,6 +193,8 @@ static void op_amd_setup_ctrs(struct op_msrs const * const msrs)
}
}

+#ifdef CONFIG_OPROFILE_IBS
+
static inline int
op_amd_handle_ibs(struct pt_regs * const regs,
struct op_msrs const * const msrs)
@@ -261,6 +268,8 @@ op_amd_handle_ibs(struct pt_regs * const regs,
return 1;
}

+#endif
+
static int op_amd_check_ctrs(struct pt_regs * const regs,
struct op_msrs const * const msrs)
{
@@ -277,7 +286,9 @@ static int op_amd_check_ctrs(struct pt_regs * const regs,
}
}

+#ifdef CONFIG_OPROFILE_IBS
op_amd_handle_ibs(regs, msrs);
+#endif

/* See op_model_ppro.c */
return 1;
@@ -294,6 +305,8 @@ static void op_amd_start(struct op_msrs const * const msrs)
CTRL_WRITE(low, high, msrs, i);
}
}
+
+#ifdef CONFIG_OPROFILE_IBS
if (ibs_allowed && ibs_config.fetch_enabled) {
low = (ibs_config.max_cnt_fetch >> 4) & 0xFFFF;
high = IBS_FETCH_HIGH_ENABLE;
@@ -305,6 +318,7 @@ static void op_amd_start(struct op_msrs const * const msrs)
high = 0;
wrmsr(MSR_AMD64_IBSOPCTL, low, high);
}
+#endif
}


@@ -323,6 +337,7 @@ static void op_amd_stop(struct op_msrs const * const msrs)
CTRL_WRITE(low, high, msrs, i);
}

+#ifdef CONFIG_OPROFILE_IBS
if (ibs_allowed && ibs_config.fetch_enabled) {
low = 0; /* clear max count and enable */
high = 0;
@@ -334,6 +349,7 @@ static void op_amd_stop(struct op_msrs const * const msrs)
high = 0;
wrmsr(MSR_AMD64_IBSOPCTL, low, high);
}
+#endif
}

static void op_amd_shutdown(struct op_msrs const * const msrs)
@@ -350,17 +366,10 @@ static void op_amd_shutdown(struct op_msrs const * const msrs)
}
}

-#ifndef CONFIG_SMP
+#ifndef CONFIG_OPROFILE_IBS

/* no IBS support */

-static void setup_ibs(void)
-{
- ibs_allowed = 0;
-}
-
-static void clear_ibs_nmi(void) {}
-
static int op_amd_init(struct oprofile_operations *ops)
{
return 0;
@@ -441,8 +450,12 @@ static void setup_ibs(void)
if (!ibs_allowed)
return;

- if (pfm_amd64_setup_eilvt())
+ if (pfm_amd64_setup_eilvt()) {
ibs_allowed = 0;
+ return;
+ }
+
+ printk(KERN_INFO "oprofile: AMD IBS detected\n");
}


diff --git a/drivers/oprofile/buffer_sync.c b/drivers/oprofile/buffer_sync.c
index e1782d2..ed98227 100644
--- a/drivers/oprofile/buffer_sync.c
+++ b/drivers/oprofile/buffer_sync.c
@@ -328,6 +328,8 @@ static void add_trace_begin(void)
add_event_entry(TRACE_BEGIN_CODE);
}

+#ifdef CONFIG_OPROFILE_IBS
+
#define IBS_FETCH_CODE_SIZE 2
#define IBS_OP_CODE_SIZE 5
#define IBS_EIP(offset) \
@@ -390,6 +392,8 @@ static void add_ibs_begin(struct oprofile_cpu_buffer *cpu_buf, int code,
}
}

+#endif
+
static void add_sample_entry(unsigned long offset, unsigned long event)
{
add_event_entry(offset);
@@ -586,6 +590,7 @@ void sync_buffer(int cpu)
} else if (s->event == CPU_TRACE_BEGIN) {
state = sb_bt_start;
add_trace_begin();
+#ifdef CONFIG_OPROFILE_IBS
} else if (s->event == IBS_FETCH_BEGIN) {
state = sb_bt_start;
add_ibs_begin(cpu_buf,
@@ -594,6 +599,7 @@ void sync_buffer(int cpu)
state = sb_bt_start;
add_ibs_begin(cpu_buf,
IBS_OP_CODE, in_kernel, mm);
+#endif
} else {
struct mm_struct *oldmm = mm;

diff --git a/drivers/oprofile/cpu_buffer.c b/drivers/oprofile/cpu_buffer.c
index c9ac4e1..aba905b 100644
--- a/drivers/oprofile/cpu_buffer.c
+++ b/drivers/oprofile/cpu_buffer.c
@@ -253,6 +253,8 @@ void oprofile_add_sample(struct pt_regs * const regs, unsigned long event)
oprofile_add_ext_sample(pc, regs, event, is_kernel);
}

+#ifdef CONFIG_OPROFILE_IBS
+
#define MAX_IBS_SAMPLE_SIZE 14
static int log_ibs_sample(struct oprofile_cpu_buffer *cpu_buf,
unsigned long pc, int is_kernel, unsigned int *ibs, int ibs_code)
@@ -318,6 +320,8 @@ void oprofile_add_ibs_sample(struct pt_regs *const regs,
oprofile_ops.backtrace(regs, backtrace_depth);
}

+#endif
+
void oprofile_add_pc(unsigned long pc, int is_kernel, unsigned long event)
{
struct oprofile_cpu_buffer *cpu_buf = &__get_cpu_var(cpu_buffer);
--
1.5.5.4


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