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 <asm/atomic.h>
  19
  20 /* Each escaped entry is prefixed by ESCAPE_CODE
  21  * then one of the following codes, then the
  22  * relevant data.
  23  * These #defines live in this file so that arch-specific
  24  * buffer sync'ing code can access them.
  25  */
  26 #define ESCAPE_CODE                     ~0UL
  27 #define CTX_SWITCH_CODE                 1
  28 #define CPU_SWITCH_CODE                 2
  29 #define COOKIE_SWITCH_CODE              3
  30 #define KERNEL_ENTER_SWITCH_CODE        4
  31 #define KERNEL_EXIT_SWITCH_CODE         5
  32 #define MODULE_LOADED_CODE              6
  33 #define CTX_TGID_CODE                   7
  34 #define TRACE_BEGIN_CODE                8
  35 #define TRACE_END_CODE                  9
  36 #define XEN_ENTER_SWITCH_CODE           10
  37 #define SPU_PROFILING_CODE              11
  38 #define SPU_CTX_SWITCH_CODE             12
  39 #define IBS_FETCH_CODE                  13
  40 #define IBS_OP_CODE                     14
  41
  42 struct super_block;
  43 struct dentry;
  44 struct file_operations;
  45 struct pt_regs;
  46
  47 /* Operations structure to be filled in */
  48 struct oprofile_operations {
  49         /* create any necessary configuration files in the oprofile fs.
  50          * Optional. */
  51         int (*create_files)(struct super_block * sb, struct dentry * root);
  52         /* Do any necessary interrupt setup. Optional. */
  53         int (*setup)(void);
  54         /* Do any necessary interrupt shutdown. Optional. */
  55         void (*shutdown)(void);
  56         /* Start delivering interrupts. */
  57         int (*start)(void);
  58         /* Stop delivering interrupts. */
  59         void (*stop)(void);
  60         /* Arch-specific buffer sync functions.
  61          * Return value = 0:  Success
  62          * Return value = -1: Failure
  63          * Return value = 1:  Run generic sync function
  64          */
  65         int (*sync_start)(void);
  66         int (*sync_stop)(void);
  67
  68         /* Initiate a stack backtrace. Optional. */
  69         void (*backtrace)(struct pt_regs * const regs, unsigned int depth);
  70         /* CPU identification string. */
  71         char * cpu_type;
  72 };
  73
  74 /**
  75  * One-time initialisation. *ops must be set to a filled-in
  76  * operations structure. This is called even in timer interrupt
  77  * mode so an arch can set a backtrace callback.
  78  *
  79  * If an error occurs, the fields should be left untouched.
  80  */
  81 int oprofile_arch_init(struct oprofile_operations * ops);
  82
  83 /**
  84  * One-time exit/cleanup for the arch.
  85  */
  86 void oprofile_arch_exit(void);
  87
  88 /**
  89  * Add data to the event buffer.
  90  * The data passed is free-form, but typically consists of
  91  * file offsets, dcookies, context information, and ESCAPE codes.
  92  */
  93 void add_event_entry(unsigned long data);
  94
  95 /**
  96  * Add a sample. This may be called from any context. Pass
  97  * smp_processor_id() as cpu.
  98  */
  99 void oprofile_add_sample(struct pt_regs * const regs, unsigned long event);
 100
 101 /**
 102  * Add an extended sample.  Use this when the PC is not from the regs, and
 103  * we cannot determine if we're in kernel mode from the regs.
 104  *
 105  * This function does perform a backtrace.
 106  *
 107  */
 108 void oprofile_add_ext_sample(unsigned long pc, struct pt_regs * const regs,
 109                                 unsigned long event, int is_kernel);
 110
 111 /* Use this instead when the PC value is not from the regs. Doesn't
 112  * backtrace. */
 113 void oprofile_add_pc(unsigned long pc, int is_kernel, unsigned long event);
 114
 115 /* add a backtrace entry, to be called from the ->backtrace callback */
 116 void oprofile_add_trace(unsigned long eip);
 117
 118
 119 /**
 120  * Create a file of the given name as a child of the given root, with
 121  * the specified file operations.
 122  */
 123 int oprofilefs_create_file(struct super_block * sb, struct dentry * root,
 124         char const * name, const struct file_operations * fops);
 125
 126 int oprofilefs_create_file_perm(struct super_block * sb, struct dentry * root,
 127         char const * name, const struct file_operations * fops, int perm);
 128
 129 /** Create a file for read/write access to an unsigned long. */
 130 int oprofilefs_create_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 unsigned long. */
 134 int oprofilefs_create_ro_ulong(struct super_block * sb, struct dentry * root,
 135         char const * name, ulong * val);
 136
 137 /** Create a file for read-only access to an atomic_t. */
 138 int oprofilefs_create_ro_atomic(struct super_block * sb, struct dentry * root,
 139         char const * name, atomic_t * val);
 140
 141 /** create a directory */
 142 struct dentry * oprofilefs_mkdir(struct super_block * sb, struct dentry * root,
 143         char const * name);
 144
 145 /**
 146  * Write the given asciz string to the given user buffer @buf, updating *offset
 147  * appropriately. Returns bytes written or -EFAULT.
 148  */
 149 ssize_t oprofilefs_str_to_user(char const * str, char __user * buf, size_t count, loff_t * offset);
 150
 151 /**
 152  * Convert an unsigned long value into ASCII and copy it to the user buffer @buf,
 153  * updating *offset appropriately. Returns bytes written or -EFAULT.
 154  */
 155 ssize_t oprofilefs_ulong_to_user(unsigned long val, char __user * buf, size_t count, loff_t * offset);
 156
 157 /**
 158  * Read an ASCII string for a number from a userspace buffer and fill *val on success.
 159  * Returns 0 on success, < 0 on error.
 160  */
 161 int oprofilefs_ulong_from_user(unsigned long * val, char const __user * buf, size_t count);
 162
 163 /** lock for read/write safety */
 164 extern spinlock_t oprofilefs_lock;
 165
 166 #endif /* OPROFILE_H */