LXR linux/include/linux/oprofile.h

   1/**
   2 * @file oprofile.h
   3 *
   4 * API for machine-specific interrupts to interface
   5 * to oprofile.
   6 *
   7 * @remark Copyright 2002 OProfile authors
   8 * @remark Read the file COPYING
   9 *
  10 * @author John Levon <levon@movementarian.org>
  11 */
  12
  13#ifndef OPROFILE_H
  14#define OPROFILE_H
  15
  16#include <linux/types.h>
  17#include <linux/spinlock.h>
  18#include <linux/init.h>
  19#include <linux/errno.h>
  20#include <linux/printk.h>
  21#include <linux/atomic.h>
  22 
  23/* Each escaped entry is prefixed by ESCAPE_CODE
  24 * then one of the following codes, then the
  25 * relevant data.
  26 * These #defines live in this file so that arch-specific
  27 * buffer sync'ing code can access them.
  28 */
  29#define ESCAPE_CODE                     ~0UL
  30#define CTX_SWITCH_CODE                 1
  31#define CPU_SWITCH_CODE                 2
  32#define COOKIE_SWITCH_CODE              3
  33#define KERNEL_ENTER_SWITCH_CODE        4
  34#define KERNEL_EXIT_SWITCH_CODE         5
  35#define MODULE_LOADED_CODE              6
  36#define CTX_TGID_CODE                   7
  37#define TRACE_BEGIN_CODE                8
  38#define TRACE_END_CODE                  9
  39#define XEN_ENTER_SWITCH_CODE           10
  40#define SPU_PROFILING_CODE              11
  41#define SPU_CTX_SWITCH_CODE             12
  42#define IBS_FETCH_CODE                  13
  43#define IBS_OP_CODE                     14
  44
  45struct dentry;
  46struct file_operations;
  47struct pt_regs;
  48 
  49/* Operations structure to be filled in */
  50struct oprofile_operations {
  51        /* create any necessary configuration files in the oprofile fs.
  52         * Optional. */
  53        int (*create_files)(struct dentry * root);
  54        /* Do any necessary interrupt setup. Optional. */
  55        int (*setup)(void);
  56        /* Do any necessary interrupt shutdown. Optional. */
  57        void (*shutdown)(void);
  58        /* Start delivering interrupts. */
  59        int (*start)(void);
  60        /* Stop delivering interrupts. */
  61        void (*stop)(void);
  62        /* Arch-specific buffer sync functions.
  63         * Return value = 0:  Success
  64         * Return value = -1: Failure
  65         * Return value = 1:  Run generic sync function
  66         */
  67        int (*sync_start)(void);
  68        int (*sync_stop)(void);
  69
  70        /* Initiate a stack backtrace. Optional. */
  71        void (*backtrace)(struct pt_regs * const regs, unsigned int depth);
  72
  73        /* Multiplex between different events. Optional. */
  74        int (*switch_events)(void);
  75        /* CPU identification string. */
  76        char * cpu_type;
  77};
  78
  79/**
  80 * One-time initialisation. *ops must be set to a filled-in
  81 * operations structure. This is called even in timer interrupt
  82 * mode so an arch can set a backtrace callback.
  83 *
  84 * If an error occurs, the fields should be left untouched.
  85 */
  86int oprofile_arch_init(struct oprofile_operations * ops);
  87 
  88/**
  89 * One-time exit/cleanup for the arch.
  90 */
  91void oprofile_arch_exit(void);
  92
  93/**
  94 * Add a sample. This may be called from any context.
  95 */
  96void oprofile_add_sample(struct pt_regs * const regs, unsigned long event);
  97
  98/**
  99 * Add an extended sample.  Use this when the PC is not from the regs, and
 100 * we cannot determine if we're in kernel mode from the regs.
 101 *
 102 * This function does perform a backtrace.
 103 *
 104 */
 105void oprofile_add_ext_sample(unsigned long pc, struct pt_regs * const regs,
 106                                unsigned long event, int is_kernel);
 107
 108/**
 109 * Add an hardware sample.
 110 */
 111void oprofile_add_ext_hw_sample(unsigned long pc, struct pt_regs * const regs,
 112        unsigned long event, int is_kernel,
 113        struct task_struct *task);
 114
 115/* Use this instead when the PC value is not from the regs. Doesn't
 116 * backtrace. */
 117void oprofile_add_pc(unsigned long pc, int is_kernel, unsigned long event);
 118
 119/* add a backtrace entry, to be called from the ->backtrace callback */
 120void oprofile_add_trace(unsigned long eip);
 121
 122
 123/**
 124 * Create a file of the given name as a child of the given root, with
 125 * the specified file operations.
 126 */
 127int oprofilefs_create_file(struct dentry * root,
 128        char const * name, const struct file_operations * fops);
 129
 130int oprofilefs_create_file_perm(struct dentry * root,
 131        char const * name, const struct file_operations * fops, int perm);
 132 
 133/** Create a file for read/write access to an unsigned long. */
 134int oprofilefs_create_ulong(struct dentry * root,
 135        char const * name, ulong * val);
 136 
 137/** Create a file for read-only access to an unsigned long. */
 138int oprofilefs_create_ro_ulong(struct dentry * root,
 139        char const * name, ulong * val);
 140 
 141/** Create a file for read-only access to an atomic_t. */
 142int oprofilefs_create_ro_atomic(struct dentry * root,
 143        char const * name, atomic_t * val);
 144 
 145/** create a directory */
 146struct dentry *oprofilefs_mkdir(struct dentry *parent, char const *name);
 147
 148/**
 149 * Write the given asciz string to the given user buffer @buf, updating *offset
 150 * appropriately. Returns bytes written or -EFAULT.
 151 */
 152ssize_t oprofilefs_str_to_user(char const * str, char __user * buf, size_t count, loff_t * offset);
 153
 154/**
 155 * Convert an unsigned long value into ASCII and copy it to the user buffer @buf,
 156 * updating *offset appropriately. Returns bytes written or -EFAULT.
 157 */
 158ssize_t oprofilefs_ulong_to_user(unsigned long val, char __user * buf, size_t count, loff_t * offset);
 159
 160/**
 161 * Read an ASCII string for a number from a userspace buffer and fill *val on success.
 162 * Returns 0 on success, < 0 on error.
 163 */
 164int oprofilefs_ulong_from_user(unsigned long * val, char const __user * buf, size_t count);
 165
 166/** lock for read/write safety */
 167extern raw_spinlock_t oprofilefs_lock;
 168
 169/**
 170 * Add the contents of a circular buffer to the event buffer.
 171 */
 172void oprofile_put_buff(unsigned long *buf, unsigned int start,
 173                        unsigned int stop, unsigned int max);
 174
 175unsigned long oprofile_get_cpu_buffer_size(void);
 176void oprofile_cpu_buffer_inc_smpl_lost(void);
 177 
 178/* cpu buffer functions */
 179
 180struct op_sample;
 181
 182struct op_entry {
 183        struct ring_buffer_event *event;
 184        struct op_sample *sample;
 185        unsigned long size;
 186        unsigned long *data;
 187};
 188
 189void oprofile_write_reserve(struct op_entry *entry,
 190                            struct pt_regs * const regs,
 191                            unsigned long pc, int code, int size);
 192int oprofile_add_data(struct op_entry *entry, unsigned long val);
 193int oprofile_add_data64(struct op_entry *entry, u64 val);
 194int oprofile_write_commit(struct op_entry *entry);
 195
 196#ifdef CONFIG_HW_PERF_EVENTS
 197int __init oprofile_perf_init(struct oprofile_operations *ops);
 198void oprofile_perf_exit(void);
 199char *op_name_from_perf_id(void);
 200#else
 201static inline int __init oprofile_perf_init(struct oprofile_operations *ops)
 202{
 203        pr_info("oprofile: hardware counters not available\n");
 204        return -ENODEV;
 205}
 206static inline void oprofile_perf_exit(void) { }
 207#endif /* CONFIG_HW_PERF_EVENTS */
 208
 209#endif /* OPROFILE_H */
 210