dtrace discuss - Sep 2008 - kernel function rl_log_control is not matched by any probe

Hello,

I need to trace the kernel function "rl_log_control" which is defined
in /usr/src/cmd/fs.d/ufs/roll_log/roll_log.c however dtrace can''t find
that probe

bash-3.00# dtrace -l -n ::rl_log_control:

   ID   PROVIDER            MODULE                          FUNCTION
NAME

dtrace: failed to match ::rl_log_control:: No probe matches description

Do you have any suggest?

 433 rl_result_t 

 434 rl_log_control(char *bdev, int request) 

 435 { 

 436         log_info_t      li; 

 437         rl_result_t     rv = RL_SUCCESS; 

 438         rl_result_t     alreadymounted; 

 439         int             fd; 

 440         fiolog_t        fl; 

 441         int             logenabled; 

 442  

 443         if ((request != _FIOLOGENABLE) && (request
!_FIOLOGDISABLE))

 444                 return (RL_FAIL); 

 445  

 446         (void) memset((void *)&li, ''\0'',
(size_t)sizeof (li));

 447         if ((alreadymounted = is_mounted(&li, bdev)) !RL_TRUE) { 

 448                 /* 

 449                  * Device is not mounted. Need to mount it rw to
allow 

 450                  * the log to be enabled/disabled. To do the
mount, we need 

 451                  * to create a temporary directory, and then
remove it when 

 452                  * we are done. 

 453                  */ 

 454                 if (make_mp(&li) != RL_SUCCESS) { 

 455                         cleanup(&li); 

 456                         return (RL_FAIL); 

 457                 } 

 458                 if (rlmount(&li, RLM_RW) != RL_SUCCESS) { 

 459                         cleanup(&li); 

 460                         return (RL_FAIL); 

 461                 } 

 462         } 

 463  

 464         if (alreadymounted == RL_TRUE) 

 465                 fd = open(li.li_mntpoint, O_RDONLY); 

 466         else 

 467                 fd = open(li.li_tmpmp, O_RDONLY); 

 468         if (fd == SYSERR) { 

 469                 perror("open"); 

 470                 rv = RL_SYSERR; 

 471                 goto out; 

 472         } 

 473  

 474         fl.nbytes_requested = 0; 

 475         fl.nbytes_actual = 0; 

 476         fl.error = FIOLOG_ENONE; 

 477  

 478         if (ioctl(fd, request, &fl) == SYSERR) { 

 479                 perror("ioctl"); 

 480                 (void) close(fd); 

 481                 rv = RL_SYSERR; 

 482                 goto out; 

 483         } 

 484         if (ioctl(fd, _FIOISLOG, &logenabled) == SYSERR) { 

 485                 perror("ioctl"); 

 486                 (void) close(fd); 

 487                 rv = RL_SYSERR; 

 488                 goto out; 

 489         } 

 490         if (((request == _FIOLOGENABLE) && (!logenabled))
|| 

 491             ((request == _FIOLOGDISABLE) && logenabled)) 

 492                 rv = RL_FAIL; 

 493  

 494         (void) close(fd); 

 495 out: 

 496         if (alreadymounted != RL_TRUE) 

 497                 (void) rlumount(&li); 

 498         cleanup(&li); 

 499         return (rv); 

 500 } 

-- 

      Andrea Cucciarre''

Storage Engineer

Sun Microsystems Italia S.p.A.

Viale Fulvio Testi, 327

20162 Milano, Italy

Phone +39 800605338

Fax     +39 0264152204

E-m@il andrea.cucciarre-UdXhSnd/wVw@public.gmane.org

Andrea Cucciarre'' - Sun Microsystems - Italy
wrote:
> I need to trace the kernel function "rl_log_control" which is
defined in
> /usr/src/cmd/fs.d/ufs/roll_log/roll_log.c however dtrace can''t
find that probe
rl_log_control is not a kernel function - it is a utility function which is
included in programs like fsck.

If you want to trace this, you will need to use the pid provider, and also
the process you want to trace must be currently running. If so, try e.g.

# dtrace -l -n ''pid<PID>:a.out:rl_log_control:entry''

Allan