Messages in this thread | | | Date | Sat, 15 Oct 2005 00:58:51 -0700 | From | Mitchell Blank Jr <> | Subject | Re: lock_kernel twice possible ? |
| |
li nux wrote: > Sorry, couldn't get what you want to say. > Can you please elaborate.
A "recursive lock" is one that can be taken multiple times by the same owner. So:
lock_kernel(); lock_kernel(); unlock_kernel(); unlock_kernel();
is perfectly ok. The lock_kernel() code detects that the calling thread already owns the lock and just increments current->lock_depth.
Under linux locks are non-recursive EXCEPT for lock_kernel() (aka the BLK or "big kernel lock")
See lib/kernel_lock.c for more details.
-Mitch - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |