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 struct super_block;
  21 struct dentry;
  22 struct file_operations;
  23 struct pt_regs;
  24
  25 /* Operations structure to be filled in */
  26 struct oprofile_operations {
  27         /* create any necessary configuration files in the oprofile fs.
  28          * Optional. */
  29         int (*create_files)(struct super_block * sb, struct dentry * root);
  30         /* Do any necessary interrupt setup. Optional. */
  31         int (*setup)(void);
  32         /* Do any necessary interrupt shutdown. Optional. */
  33         void (*shutdown)(void);
  34         /* Start delivering interrupts. */
  35         int (*start)(void);
  36         /* Stop delivering interrupts. */
  37         void (*stop)(void);
  38         /* Initiate a stack backtrace. Optional. */
  39         void (*backtrace)(struct pt_regs * const regs, unsigned int depth);
  40         /* CPU identification string. */
  41         char * cpu_type;
  42 };
  43
  44 /**
  45  * One-time initialisation. *ops must be set to a filled-in
  46  * operations structure. This is called even in timer interrupt
  47  * mode so an arch can set a backtrace callback.
  48  *
  49  * If an error occurs, the fields should be left untouched.
  50  */
  51 int oprofile_arch_init(struct oprofile_operations * ops);
  52
  53 /**
  54  * One-time exit/cleanup for the arch.
  55  */
  56 void oprofile_arch_exit(void);
  57
  58 /**
  59  * Add a sample. This may be called from any context. Pass
  60  * smp_processor_id() as cpu.
  61  */
  62 void oprofile_add_sample(struct pt_regs * const regs, unsigned long event);
  63
  64 /**
  65  * Add an extended sample.  Use this when the PC is not from the regs, and
  66  * we cannot determine if we're in kernel mode from the regs.
  67  *
  68  * This function does perform a backtrace.
  69  *
  70  */
  71 void oprofile_add_ext_sample(unsigned long pc, struct pt_regs * const regs,
  72                                 unsigned long event, int is_kernel);
  73
  74 /* Use this instead when the PC value is not from the regs. Doesn't
  75  * backtrace. */
  76 void oprofile_add_pc(unsigned long pc, int is_kernel, unsigned long event);
  77
  78 /* add a backtrace entry, to be called from the ->backtrace callback */
  79 void oprofile_add_trace(unsigned long eip);
  80
  81
  82 /**
  83  * Create a file of the given name as a child of the given root, with
  84  * the specified file operations.
  85  */
  86 int oprofilefs_create_file(struct super_block * sb, struct dentry * root,
  87         char const * name, const struct file_operations * fops);
  88
  89 int oprofilefs_create_file_perm(struct super_block * sb, struct dentry * root,
  90         char const * name, const struct file_operations * fops, int perm);
  91
  92 /** Create a file for read/write access to an unsigned long. */
  93 int oprofilefs_create_ulong(struct super_block * sb, struct dentry * root,
  94         char const * name, ulong * val);
  95
  96 /** Create a file for read-only access to an unsigned long. */
  97 int oprofilefs_create_ro_ulong(struct super_block * sb, struct dentry * root,
  98         char const * name, ulong * val);
  99
 100 /** Create a file for read-only access to an atomic_t. */
 101 int oprofilefs_create_ro_atomic(struct super_block * sb, struct dentry * root,
 102         char const * name, atomic_t * val);
 103
 104 /** create a directory */
 105 struct dentry * oprofilefs_mkdir(struct super_block * sb, struct dentry * root,
 106         char const * name);
 107
 108 /**
 109  * Write the given asciz string to the given user buffer @buf, updating *offset
 110  * appropriately. Returns bytes written or -EFAULT.
 111  */
 112 ssize_t oprofilefs_str_to_user(char const * str, char __user * buf, size_t count, loff_t * offset);
 113
 114 /**
 115  * Convert an unsigned long value into ASCII and copy it to the user buffer @buf,
 116  * updating *offset appropriately. Returns bytes written or -EFAULT.
 117  */
 118 ssize_t oprofilefs_ulong_to_user(unsigned long val, char __user * buf, size_t count, loff_t * offset);
 119
 120 /**
 121  * Read an ASCII string for a number from a userspace buffer and fill *val on success.
 122  * Returns 0 on success, < 0 on error.
 123  */
 124 int oprofilefs_ulong_from_user(unsigned long * val, char const __user * buf, size_t count);
 125
 126 /** lock for read/write safety */
 127 extern spinlock_t oprofilefs_lock;
 128
 129 #endif /* OPROFILE_H */