Minor editorial fixes:
- remove 'enabled' from PREEMPT_RT enabled kernels for consistency
- add some periods for consistency
- add "'" for possessive CPU's
- spell out interrupts
[ tglx: Picked up Paul's suggestions ]
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lkml.kernel.org/r/ac615f36-0b44-408d-aeab-d76e4241add4@infradead.org
The documentation of rw_semaphores is wrong as it claims that the non-owner
reader release is not supported by RT. That's just history biased memory
distortion.
Split the 'Owner semantics' section up and add separate sections for
semaphore and rw_semaphore to reflect reality.
Aside of that the following updates are done:
- Add pseudo code to document the spinlock state preserving mechanism on
PREEMPT_RT
- Wordsmith the bitspinlock and lock nesting sections
Co-developed-by: Paul McKenney <paulmck@kernel.org>
Signed-off-by: Paul McKenney <paulmck@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://lkml.kernel.org/r/87wo78y5yy.fsf@nanos.tec.linutronix.de
The kernel provides a variety of locking primitives. The nesting of these
lock types and the implications of them on RT enabled kernels is nowhere
documented.
Add initial documentation.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200321113242.026561244@linutronix.de