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
  45 struct dentry;
  46 struct file_operations;
  47 struct pt_regs;
  48
  49 /* Operations structure to be filled in */
  50 struct 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  */
  86 int oprofile_arch_init(struct oprofile_operations * ops);
  87
  88 /**
  89  * One-time exit/cleanup for the arch.
  90  */
  91 void oprofile_arch_exit(void);
  92
  93 /**
  94  * Add a sample. This may be called from any context.
  95  */
  96 void 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  */
 105 void 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  */
 111 void 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. */
 117 void 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 */
 120 void 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  */
 127 int oprofilefs_create_file(struct dentry * root,
 128         char const * name, const struct file_operations * fops);
 129
 130 int 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. */
 134 int 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. */
 138 int 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. */
 142 int oprofilefs_create_ro_atomic(struct dentry * root,
 143         char const * name, atomic_t * val);
 144
 145 /** create a directory */
 146 struct 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  */
 152 ssize_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  */
 158 ssize_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  */
 164 int oprofilefs_ulong_from_user(unsigned long * val, char const __user * buf, size_t count);
 165
 166 /** lock for read/write safety */
 167 extern raw_spinlock_t oprofilefs_lock;
 168
 169 /**
 170  * Add the contents of a circular buffer to the event buffer.
 171  */
 172 void oprofile_put_buff(unsigned long *buf, unsigned int start,
 173                         unsigned int stop, unsigned int max);
 174
 175 unsigned long oprofile_get_cpu_buffer_size(void);
 176 void oprofile_cpu_buffer_inc_smpl_lost(void);
 177
 178 /* cpu buffer functions */
 179
 180 struct op_sample;
 181
 182 struct op_entry {
 183         struct ring_buffer_event *event;
 184         struct op_sample *sample;
 185         unsigned long size;
 186         unsigned long *data;
 187 };
 188
 189 void oprofile_write_reserve(struct op_entry *entry,
 190                             struct pt_regs * const regs,
 191                             unsigned long pc, int code, int size);
 192 int oprofile_add_data(struct op_entry *entry, unsigned long val);
 193 int oprofile_add_data64(struct op_entry *entry, u64 val);
 194 int oprofile_write_commit(struct op_entry *entry);
 195
 196 #ifdef CONFIG_HW_PERF_EVENTS
 197 int __init oprofile_perf_init(struct oprofile_operations *ops);
 198 void oprofile_perf_exit(void);
 199 char *op_name_from_perf_id(void);
 200 #else
 201 static inline int __init oprofile_perf_init(struct oprofile_operations *ops)
 202 {
 203         pr_info("oprofile: hardware counters not available\n");
 204         return -ENODEV;
 205 }
 206 static inline void oprofile_perf_exit(void) { }
 207 #endif /* CONFIG_HW_PERF_EVENTS */
 208
 209 #endif /* OPROFILE_H */