Download Sun Studio 12: Thread Analyzer User's Guide

3.4 Understanding the Experiment Results
Lock being
Thread #5
Lock being
Lock being
Thread #6
Lock being
Lock being
requested:
0x215f0, at: grab_chopstick + 0x0000002C, line 101 in "din_philo.c"
held:
0x215f0, at: grab_chopstick + 0x0000002C, line 101 in "din_philo.c"
requested:
0x21608, at: grab_chopstick + 0x0000002C, line 101 in "din_philo.c"
held:
0x21608, at: grab_chopstick + 0x0000002C, line 101 in "din_philo.c"
requested:
0x215a8, at: grab_chopstick + 0x0000002C, line 101 in "din_philo.c"
Deadlocks List Summary: Experiment: tha.1.er Total Deadlocks: 2
(er_print)
The following screen-shot shows the Thread Analyzer's presentation of the deadlock
information:
The Thread Analyzer reports two deadlocks for din_philo.c, one potential and the other
actual. On closer inspection, we find that the two deadlocks are identical. The circular chain
involved in the deadlock is as follows:
Thread 2: holds lock at address 0x215a8, requests lock at address 0x215c0
Thread 3: holds lock at address 0x215c0, requests lock at address 0x215d8
Thread 4: holds lock at address 0x215d8, requests lock at address 0x215f0
Thread 5: holds lock at address 0x215f0, requests lock at address 0x21608
Thread 6: holds lock at address 0x21608, requests lock at address 0x215a8
Select the first thread in the chain (Thread #2) and then click on the Dual Source tab to see
where in the source code Thread #2 held the lock at address 0x215a8, and where in the source
code it requested the lock at address 0x215c0. The following screen-shot shows the Dual Source
tab for thread number two. The default metric (Exclusive Deadlocks metric) is shown to the left
Chapter 3 • The Deadlock Tutorial
51