00001 /** Logs data.
-00002  * This function is compatible with printk.  In fact it currently
-00003  * sends all output to vprintk, after sending "STP: ". This allows
-00004  * us to easily detect SystemTap output in the log file.
-00005  *
-00006  * @param fmt A variable number of args.
-00007  * @bug Lines are limited in length by printk buffer.
-00008  * @todo Needs replaced with something much faster that does not
-00009  * use the system log.
-00010  */
-00011 void dlog (const char *fmt, ...)
-00012 {
-00013   va_list args;
-00014   printk("STP: ");
-00015   va_start(args, fmt);
-00016   vprintk(fmt, args);
-00017   va_end(args);
-00018 }
-00019 
-00020 
-00021 static const char * (*_stp_kallsyms_lookup)(unsigned long addr,
-00022                             unsigned long *symbolsize,
-00023                             unsigned long *offset,
-00024                             char **modname, char *namebuf)=(void *)KALLSYMS_LOOKUP;
-00025 
-00026 
-00027 #define STP_BUF_LEN 8191
-00028 
-00029 /* FIXME. These need to be per-cpu */
-00030 static char _stp_pbuf[STP_BUF_LEN+1];
-00031 static int _stp_pbuf_len = STP_BUF_LEN;
-00032 
-00033 void _stp_print_buf (const char *fmt, ...)
-00034 {
-00035   int num;
-00036   va_list args;
-00037   char *buf = _stp_pbuf + STP_BUF_LEN - _stp_pbuf_len;
-00038   va_start(args, fmt);
-00039   num = vscnprintf(buf, _stp_pbuf_len, fmt, args);
-00040   va_end(args);
-00041   if (num > 0)
-00042     _stp_pbuf_len -= num;
-00043 }
-00044 
-00045 void _stp_print_buf_init (void)
-00046 {
-00047   _stp_pbuf_len = STP_BUF_LEN;
-00048   _stp_pbuf[0] = 0;
-00049 }
-00050 
-00051 void _stp_print_symbol(const char *fmt, unsigned long address)
-00052 {
-00053         char *modname;
-00054         const char *name;
-00055         unsigned long offset, size;
-00056         char namebuf[KSYM_NAME_LEN+1];
-00057 
-00058         name = _stp_kallsyms_lookup(address, &size, &offset, &modname, namebuf);
-00059 
-00060         if (!name)
-00061                 _stp_print_buf("0x%lx", address);
-00062         else {
-00063           if (modname)
-00064             _stp_print_buf("%s+%#lx/%#lx [%s]", name, offset,
-00065                            size, modname);
-00066           else
-00067             _stp_print_buf("%s+%#lx/%#lx", name, offset, size);
-00068         }
-00069 }
-00070 
-00071  
-00072 unsigned long cur_ret_addr (struct pt_regs *regs)
+io.c
Go to the documentation of this file.00001 /* -*- linux-c -*- */
+00002 /** @file io.c
+00003  * @brief I/O functions
+00004  */
+00005 
+00006 /** Logs data.
+00007  * This function is compatible with printk.  In fact it currently
+00008  * sends all output to vprintk, after sending "STP: ". This allows
+00009  * us to easily detect SystemTap output in the log file.
+00010  *
+00011  * @param fmt A variable number of args.
+00012  * @bug Lines are limited in length by printk buffer.
+00013  * @todo Needs replaced with something much faster that does not
+00014  * use the system log.
+00015  */
+00016 void dlog (const char *fmt, ...)
+00017 {
+00018   va_list args;
+00019   printk("STP: ");
+00020   va_start(args, fmt);
+00021   vprintk(fmt, args);
+00022   va_end(args);
+00023 }
+00024 
+00025 
+00026 /** Lookup symbol.
+00027  * This simply calls the kernel function kallsyms_lookup().
+00028  * That function is not exported, so this workaround is required.
+00029  * See the kernel source, kernel/kallsyms.c for more information.
+00030  */
+00031 static const char * (*_stp_kallsyms_lookup)(unsigned long addr,
+00032                             unsigned long *symbolsize,
+00033                             unsigned long *offset,
+00034                             char **modname, char *namebuf)=(void *)KALLSYMS_LOOKUP;
+00035 
+00036 
+00037 #define STP_BUF_LEN 8191
+00038 
+00039 /** Static buffer for printing */
+00040 static char _stp_pbuf[STP_BUF_LEN+1];
+00041 static int _stp_pbuf_len = STP_BUF_LEN;
+00042 
+00043 /** Print into the print buffer.
+00044  * Like printf, except output goes into  _stp_pbuf,
+00045  * which will contain the null-terminated output.
+00046  * Safe because overflowing _stp_pbuf is not allowed.
+00047  * Size is limited by length of print buffer.
+00048  *
+00049  * @param fmt A variable number of args.
+00050  * @note Formatting output should never be done within
+00051  * a probe. Use at module exit time.
+00052  * @sa _stp_print_buf_init
+00053  */
+00054 
+00055 void _stp_print_buf (const char *fmt, ...)
+00056 {
+00057   int num;
+00058   va_list args;
+00059   char *buf = _stp_pbuf + STP_BUF_LEN - _stp_pbuf_len;
+00060   va_start(args, fmt);
+00061   num = vscnprintf(buf, _stp_pbuf_len, fmt, args);
+00062   va_end(args);
+00063   if (num > 0)
+00064     _stp_pbuf_len -= num;
+00065 }
+00066 
+00067 /** Clear the print buffer.
+00068  * Output from _stp_print_buf() will accumulate in the buffer
+00069  * until this is called.
+00070  */
+00071 
+00072 void _stp_print_buf_init (void)
 00073 {
-00074 #ifdef __x86_64__
-00075   unsigned long *ra = (unsigned long *)regs->rsp;
-00076 #else
-00077   unsigned long *ra = (unsigned long *)regs->esp;
-00078 #endif
-00079   if (ra)
-00080     return *ra;
-00081   else
-00082     return 0;
-00083 }
+00074   _stp_pbuf_len = STP_BUF_LEN;
+00075   _stp_pbuf[0] = 0;
+00076 }
+00077 
+00078 /** Print addresses symbolically into the print buffer.
+00079  * @param fmt A variable number of args.
+00080  * @param address The address to lookup.
+00081  * @note Formatting output should never be done within
+00082  * a probe. Use at module exit time.
+00083  */
+00084 
+00085 void _stp_print_symbol(const char *fmt, unsigned long address)
+00086 {
+00087         char *modname;
+00088         const char *name;
+00089         unsigned long offset, size;
+00090         char namebuf[KSYM_NAME_LEN+1];
+00091 
+00092         name = _stp_kallsyms_lookup(address, &size, &offset, &modname, namebuf);
+00093 
+00094         if (!name)
+00095                 _stp_print_buf("0x%lx", address);
+00096         else {
+00097           if (modname)
+00098             _stp_print_buf("%s+%#lx/%#lx [%s]", name, offset,
+00099                            size, modname);
+00100           else
+00101             _stp_print_buf("%s+%#lx/%#lx", name, offset, size);
+00102         }
+00103 }
+00104 
+00105 /** Get the current return address.
+00106  * Call from kprobes (not jprobes).
+00107  * @param regs The pt_regs saved by the kprobe.
+00108  * @return The return address saved in esp or rsp.
+00109  * @note i386 and x86_64 only.
+00110  */
+00111  
+00112 unsigned long cur_ret_addr (struct pt_regs *regs)
+00113 {
+00114 #ifdef __x86_64__
+00115   unsigned long *ra = (unsigned long *)regs->rsp;
+00116 #else
+00117   unsigned long *ra = (unsigned long *)regs->esp;
+00118 #endif
+00119   if (ra)
+00120     return *ra;
+00121   else
+00122     return 0;
+00123 }
 

-Generated on Tue Mar 22 00:32:02 2005 for SystemTap.
+Generated on Tue Mar 22 10:27:36 2005 for SystemTap.
 
-- 
cgit