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