Commit Graph

4 Commits

Author SHA1 Message Date
Jonathan Corbet 81584a6a77 docs: remove :c:func: from refcount-vs-atomic.rst
As of 5.3, the automarkup extension will do the right thing with function()
notation, so we don't need to clutter the text with :c:func: invocations.
So remove them.

Looking at the generated output reveals that we lack kerneldoc coverage for
much of this API, but that's a separate problem.

Acked-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-10-07 09:08:56 -06:00
Elena Reshetova 47b8f3ab9c refcount_t: Add ACQUIRE ordering on success for dec(sub)_and_test() variants
This adds an smp_acquire__after_ctrl_dep() barrier on successful
decrease of refcounter value from 1 to 0 for refcount_dec(sub)_and_test
variants and therefore gives stronger memory ordering guarantees than
prior versions of these functions.

Co-developed-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Andrea Parri <andrea.parri@amarulasolutions.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: dvyukov@google.com
Cc: keescook@chromium.org
Cc: stern@rowland.harvard.edu
Link: https://lkml.kernel.org/r/1548847131-27854-2-git-send-email-elena.reshetova@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-04 09:03:31 +01:00
Andrea Parri a9251553c2 Documentation: refcount-vs-atomic: Update reference to LKMM doc.
The LKMM project has moved to 'tools/memory-model/'.

Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-05-08 14:52:39 -06:00
Elena Reshetova b6e859f6cd docs: refcount_t documentation
Some functions from refcount_t API provide different
memory ordering guarantees that their atomic counterparts.
This adds a document outlining these differences (
Documentation/core-api/refcount-vs-atomic.rst) as well as
some other minor improvements.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-12-11 14:37:11 -07:00