Rev 6295 | Show entire file | Regard whitespace | Details | Blame | Last modification | View Log | RSS feed
| Rev 6295 | Rev 6936 | ||
|---|---|---|---|
| Line 824... | Line 824... | ||
| 824 | * and call this function with @use_ticket == 1 and @ticket->stamp == the unique |
824 | * and call this function with @use_ticket == 1 and @ticket->stamp == the unique |
| 825 | * sequence number. If upon call of this function, the buffer object is already |
825 | * sequence number. If upon call of this function, the buffer object is already |
| 826 | * reserved, the validation sequence is checked against the validation |
826 | * reserved, the validation sequence is checked against the validation |
| 827 | * sequence of the process currently reserving the buffer, |
827 | * sequence of the process currently reserving the buffer, |
| 828 | * and if the current validation sequence is greater than that of the process |
828 | * and if the current validation sequence is greater than that of the process |
| 829 | * holding the reservation, the function returns -EAGAIN. Otherwise it sleeps |
829 | * holding the reservation, the function returns -EDEADLK. Otherwise it sleeps |
| 830 | * waiting for the buffer to become unreserved, after which it retries |
830 | * waiting for the buffer to become unreserved, after which it retries |
| 831 | * reserving. |
831 | * reserving. |
| 832 | * The caller should, when receiving an -EAGAIN error |
832 | * The caller should, when receiving an -EDEADLK error |
| 833 | * release all its buffer reservations, wait for @bo to become unreserved, and |
833 | * release all its buffer reservations, wait for @bo to become unreserved, and |
| 834 | * then rerun the validation with the same validation sequence. This procedure |
834 | * then rerun the validation with the same validation sequence. This procedure |
| 835 | * will always guarantee that the process with the lowest validation sequence |
835 | * will always guarantee that the process with the lowest validation sequence |
| 836 | * will eventually succeed, preventing both deadlocks and starvation. |
836 | * will eventually succeed, preventing both deadlocks and starvation. |
| 837 | * |
837 | * |