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Diffstat (limited to 'Documentation/kernel-hacking/locking.rst')
| -rw-r--r-- | Documentation/kernel-hacking/locking.rst | 7 |
1 files changed, 2 insertions, 5 deletions
diff --git a/Documentation/kernel-hacking/locking.rst b/Documentation/kernel-hacking/locking.rst index e6cd40663ea5..6805ae6e86e6 100644 --- a/Documentation/kernel-hacking/locking.rst +++ b/Documentation/kernel-hacking/locking.rst @@ -295,7 +295,7 @@ Pete Zaitcev gives the following summary: - If you are in a process context (any syscall) and want to lock other process out, use a mutex. You can take a mutex and sleep - (``copy_from_user*(`` or ``kmalloc(x,GFP_KERNEL)``). + (``copy_from_user()`` or ``kmalloc(x,GFP_KERNEL)``). - Otherwise (== data can be touched in an interrupt), use spin_lock_irqsave() and @@ -941,8 +941,7 @@ lock. A classic problem here is when you provide callbacks or hooks: if you call these with the lock held, you risk simple deadlock, or a deadly -embrace (who knows what the callback will do?). Remember, the other -programmers are out to get you, so don't do this. +embrace (who knows what the callback will do?). Overzealous Prevention Of Deadlocks ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ @@ -952,8 +951,6 @@ grabs a read lock, searches a list, fails to find what it wants, drops the read lock, grabs a write lock and inserts the object has a race condition. -If you don't see why, please stay away from my code. - Racing Timers: A Kernel Pastime ------------------------------- |