![Markus Metzger](/assets/img/avatar_default.png)
Add debug store support for Core i7. Core i7 adds a reset value for each performance counter and a new PEBS record format. Signed-off-by: Markus Metzger <markus.t.metzger@intel.com> Cc: roland@redhat.com Cc: eranian@googlemail.com Cc: oleg@redhat.com Cc: juan.villacis@intel.com Cc: ak@linux.jf.intel.com LKML-Reference: <20090403144607.088997000@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
303 lines
7.8 KiB
C
303 lines
7.8 KiB
C
/*
|
|
* Debug Store (DS) support
|
|
*
|
|
* This provides a low-level interface to the hardware's Debug Store
|
|
* feature that is used for branch trace store (BTS) and
|
|
* precise-event based sampling (PEBS).
|
|
*
|
|
* It manages:
|
|
* - DS and BTS hardware configuration
|
|
* - buffer overflow handling (to be done)
|
|
* - buffer access
|
|
*
|
|
* It does not do:
|
|
* - security checking (is the caller allowed to trace the task)
|
|
* - buffer allocation (memory accounting)
|
|
*
|
|
*
|
|
* Copyright (C) 2007-2009 Intel Corporation.
|
|
* Markus Metzger <markus.t.metzger@intel.com>, 2007-2009
|
|
*/
|
|
|
|
#ifndef _ASM_X86_DS_H
|
|
#define _ASM_X86_DS_H
|
|
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/init.h>
|
|
#include <linux/err.h>
|
|
|
|
|
|
#ifdef CONFIG_X86_DS
|
|
|
|
struct task_struct;
|
|
struct ds_context;
|
|
struct ds_tracer;
|
|
struct bts_tracer;
|
|
struct pebs_tracer;
|
|
|
|
typedef void (*bts_ovfl_callback_t)(struct bts_tracer *);
|
|
typedef void (*pebs_ovfl_callback_t)(struct pebs_tracer *);
|
|
|
|
|
|
/*
|
|
* A list of features plus corresponding macros to talk about them in
|
|
* the ds_request function's flags parameter.
|
|
*
|
|
* We use the enum to index an array of corresponding control bits;
|
|
* we use the macro to index a flags bit-vector.
|
|
*/
|
|
enum ds_feature {
|
|
dsf_bts = 0,
|
|
dsf_bts_kernel,
|
|
#define BTS_KERNEL (1 << dsf_bts_kernel)
|
|
/* trace kernel-mode branches */
|
|
|
|
dsf_bts_user,
|
|
#define BTS_USER (1 << dsf_bts_user)
|
|
/* trace user-mode branches */
|
|
|
|
dsf_bts_overflow,
|
|
dsf_bts_max,
|
|
dsf_pebs = dsf_bts_max,
|
|
|
|
dsf_pebs_max,
|
|
dsf_ctl_max = dsf_pebs_max,
|
|
dsf_bts_timestamps = dsf_ctl_max,
|
|
#define BTS_TIMESTAMPS (1 << dsf_bts_timestamps)
|
|
/* add timestamps into BTS trace */
|
|
|
|
#define BTS_USER_FLAGS (BTS_KERNEL | BTS_USER | BTS_TIMESTAMPS)
|
|
};
|
|
|
|
|
|
/*
|
|
* Request BTS or PEBS
|
|
*
|
|
* Due to alignement constraints, the actual buffer may be slightly
|
|
* smaller than the requested or provided buffer.
|
|
*
|
|
* Returns a pointer to a tracer structure on success, or
|
|
* ERR_PTR(errcode) on failure.
|
|
*
|
|
* The interrupt threshold is independent from the overflow callback
|
|
* to allow users to use their own overflow interrupt handling mechanism.
|
|
*
|
|
* The function might sleep.
|
|
*
|
|
* task: the task to request recording for
|
|
* cpu: the cpu to request recording for
|
|
* base: the base pointer for the (non-pageable) buffer;
|
|
* size: the size of the provided buffer in bytes
|
|
* ovfl: pointer to a function to be called on buffer overflow;
|
|
* NULL if cyclic buffer requested
|
|
* th: the interrupt threshold in records from the end of the buffer;
|
|
* -1 if no interrupt threshold is requested.
|
|
* flags: a bit-mask of the above flags
|
|
*/
|
|
extern struct bts_tracer *ds_request_bts_task(struct task_struct *task,
|
|
void *base, size_t size,
|
|
bts_ovfl_callback_t ovfl,
|
|
size_t th, unsigned int flags);
|
|
extern struct bts_tracer *ds_request_bts_cpu(int cpu, void *base, size_t size,
|
|
bts_ovfl_callback_t ovfl,
|
|
size_t th, unsigned int flags);
|
|
extern struct pebs_tracer *ds_request_pebs_task(struct task_struct *task,
|
|
void *base, size_t size,
|
|
pebs_ovfl_callback_t ovfl,
|
|
size_t th, unsigned int flags);
|
|
extern struct pebs_tracer *ds_request_pebs_cpu(int cpu,
|
|
void *base, size_t size,
|
|
pebs_ovfl_callback_t ovfl,
|
|
size_t th, unsigned int flags);
|
|
|
|
/*
|
|
* Release BTS or PEBS resources
|
|
* Suspend and resume BTS or PEBS tracing
|
|
*
|
|
* Must be called with irq's enabled.
|
|
*
|
|
* tracer: the tracer handle returned from ds_request_~()
|
|
*/
|
|
extern void ds_release_bts(struct bts_tracer *tracer);
|
|
extern void ds_suspend_bts(struct bts_tracer *tracer);
|
|
extern void ds_resume_bts(struct bts_tracer *tracer);
|
|
extern void ds_release_pebs(struct pebs_tracer *tracer);
|
|
extern void ds_suspend_pebs(struct pebs_tracer *tracer);
|
|
extern void ds_resume_pebs(struct pebs_tracer *tracer);
|
|
|
|
/*
|
|
* Release BTS or PEBS resources
|
|
* Suspend and resume BTS or PEBS tracing
|
|
*
|
|
* Cpu tracers must call this on the traced cpu.
|
|
* Task tracers must call ds_release_~_noirq() for themselves.
|
|
*
|
|
* May be called with irq's disabled.
|
|
*
|
|
* Returns 0 if successful;
|
|
* -EPERM if the cpu tracer does not trace the current cpu.
|
|
* -EPERM if the task tracer does not trace itself.
|
|
*
|
|
* tracer: the tracer handle returned from ds_request_~()
|
|
*/
|
|
extern int ds_release_bts_noirq(struct bts_tracer *tracer);
|
|
extern int ds_suspend_bts_noirq(struct bts_tracer *tracer);
|
|
extern int ds_resume_bts_noirq(struct bts_tracer *tracer);
|
|
extern int ds_release_pebs_noirq(struct pebs_tracer *tracer);
|
|
extern int ds_suspend_pebs_noirq(struct pebs_tracer *tracer);
|
|
extern int ds_resume_pebs_noirq(struct pebs_tracer *tracer);
|
|
|
|
|
|
/*
|
|
* The raw DS buffer state as it is used for BTS and PEBS recording.
|
|
*
|
|
* This is the low-level, arch-dependent interface for working
|
|
* directly on the raw trace data.
|
|
*/
|
|
struct ds_trace {
|
|
/* the number of bts/pebs records */
|
|
size_t n;
|
|
/* the size of a bts/pebs record in bytes */
|
|
size_t size;
|
|
/* pointers into the raw buffer:
|
|
- to the first entry */
|
|
void *begin;
|
|
/* - one beyond the last entry */
|
|
void *end;
|
|
/* - one beyond the newest entry */
|
|
void *top;
|
|
/* - the interrupt threshold */
|
|
void *ith;
|
|
/* flags given on ds_request() */
|
|
unsigned int flags;
|
|
};
|
|
|
|
/*
|
|
* An arch-independent view on branch trace data.
|
|
*/
|
|
enum bts_qualifier {
|
|
bts_invalid,
|
|
#define BTS_INVALID bts_invalid
|
|
|
|
bts_branch,
|
|
#define BTS_BRANCH bts_branch
|
|
|
|
bts_task_arrives,
|
|
#define BTS_TASK_ARRIVES bts_task_arrives
|
|
|
|
bts_task_departs,
|
|
#define BTS_TASK_DEPARTS bts_task_departs
|
|
|
|
bts_qual_bit_size = 4,
|
|
bts_qual_max = (1 << bts_qual_bit_size),
|
|
};
|
|
|
|
struct bts_struct {
|
|
__u64 qualifier;
|
|
union {
|
|
/* BTS_BRANCH */
|
|
struct {
|
|
__u64 from;
|
|
__u64 to;
|
|
} lbr;
|
|
/* BTS_TASK_ARRIVES or BTS_TASK_DEPARTS */
|
|
struct {
|
|
__u64 clock;
|
|
pid_t pid;
|
|
} event;
|
|
} variant;
|
|
};
|
|
|
|
|
|
/*
|
|
* The BTS state.
|
|
*
|
|
* This gives access to the raw DS state and adds functions to provide
|
|
* an arch-independent view of the BTS data.
|
|
*/
|
|
struct bts_trace {
|
|
struct ds_trace ds;
|
|
|
|
int (*read)(struct bts_tracer *tracer, const void *at,
|
|
struct bts_struct *out);
|
|
int (*write)(struct bts_tracer *tracer, const struct bts_struct *in);
|
|
};
|
|
|
|
|
|
/*
|
|
* The PEBS state.
|
|
*
|
|
* This gives access to the raw DS state and the PEBS-specific counter
|
|
* reset value.
|
|
*/
|
|
struct pebs_trace {
|
|
struct ds_trace ds;
|
|
|
|
/* the number of valid counters in the below array */
|
|
unsigned int counters;
|
|
|
|
#define MAX_PEBS_COUNTERS 4
|
|
/* the counter reset value */
|
|
unsigned long long counter_reset[MAX_PEBS_COUNTERS];
|
|
};
|
|
|
|
|
|
/*
|
|
* Read the BTS or PEBS trace.
|
|
*
|
|
* Returns a view on the trace collected for the parameter tracer.
|
|
*
|
|
* The view remains valid as long as the traced task is not running or
|
|
* the tracer is suspended.
|
|
* Writes into the trace buffer are not reflected.
|
|
*
|
|
* tracer: the tracer handle returned from ds_request_~()
|
|
*/
|
|
extern const struct bts_trace *ds_read_bts(struct bts_tracer *tracer);
|
|
extern const struct pebs_trace *ds_read_pebs(struct pebs_tracer *tracer);
|
|
|
|
|
|
/*
|
|
* Reset the write pointer of the BTS/PEBS buffer.
|
|
*
|
|
* Returns 0 on success; -Eerrno on error
|
|
*
|
|
* tracer: the tracer handle returned from ds_request_~()
|
|
*/
|
|
extern int ds_reset_bts(struct bts_tracer *tracer);
|
|
extern int ds_reset_pebs(struct pebs_tracer *tracer);
|
|
|
|
/*
|
|
* Set the PEBS counter reset value.
|
|
*
|
|
* Returns 0 on success; -Eerrno on error
|
|
*
|
|
* tracer: the tracer handle returned from ds_request_pebs()
|
|
* counter: the index of the counter
|
|
* value: the new counter reset value
|
|
*/
|
|
extern int ds_set_pebs_reset(struct pebs_tracer *tracer,
|
|
unsigned int counter, u64 value);
|
|
|
|
/*
|
|
* Initialization
|
|
*/
|
|
struct cpuinfo_x86;
|
|
extern void __cpuinit ds_init_intel(struct cpuinfo_x86 *);
|
|
|
|
/*
|
|
* Context switch work
|
|
*/
|
|
extern void ds_switch_to(struct task_struct *prev, struct task_struct *next);
|
|
|
|
#else /* CONFIG_X86_DS */
|
|
|
|
struct cpuinfo_x86;
|
|
static inline void __cpuinit ds_init_intel(struct cpuinfo_x86 *ignored) {}
|
|
static inline void ds_switch_to(struct task_struct *prev,
|
|
struct task_struct *next) {}
|
|
|
|
#endif /* CONFIG_X86_DS */
|
|
#endif /* _ASM_X86_DS_H */
|