Commit cf486472 authored by Ahmed S. Darwish's avatar Ahmed S. Darwish Committed by Peter Zijlstra
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Documentation: seqlock: s/LOCKTYPE/LOCKNAME/g 



Sequence counters with an associated write serialization lock are called
seqcount_LOCKNAME_t. Fix the documentation accordingly.

While at it, remove a paragraph that inappropriately discussed a
seqlock.h implementation detail.

Fixes: 6dd699b1 ("seqlock: seqcount_LOCKNAME_t: Standardize naming convention")
Signed-off-by: default avatarAhmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20201206162143.14387-2-a.darwish@linutronix.de
parent 617f3ef9

Documentation/locking/seqlock.rst

+10 −11
Original line number Diff line number Diff line
@@ -89,7 +89,7 @@ Read path:: 


.. _seqcount_locktype_t:



Sequence counters with associated locks (``seqcount_LOCKTYPE_t``)

Sequence counters with associated locks (``seqcount_LOCKNAME_t``)

-----------------------------------------------------------------



As discussed at :ref:`seqcount_t`, sequence count write side critical
@@ -115,27 +115,26 @@ The following sequence counters with associated locks are defined: 
  - ``seqcount_mutex_t``

  - ``seqcount_ww_mutex_t``



The plain seqcount read and write APIs branch out to the specific

seqcount_LOCKTYPE_t implementation at compile-time. This avoids kernel

API explosion per each new seqcount LOCKTYPE.

The sequence counter read and write APIs can take either a plain

seqcount_t or any of the seqcount_LOCKNAME_t variants above.



Initialization (replace "LOCKTYPE" with one of the supported locks)::

Initialization (replace "LOCKNAME" with one of the supported locks)::



	/* dynamic */

	seqcount_LOCKTYPE_t foo_seqcount;

	seqcount_LOCKTYPE_init(&foo_seqcount, &lock);

	seqcount_LOCKNAME_t foo_seqcount;

	seqcount_LOCKNAME_init(&foo_seqcount, &lock);



	/* static */

	static seqcount_LOCKTYPE_t foo_seqcount =

		SEQCNT_LOCKTYPE_ZERO(foo_seqcount, &lock);

	static seqcount_LOCKNAME_t foo_seqcount =

		SEQCNT_LOCKNAME_ZERO(foo_seqcount, &lock);



	/* C99 struct init */

	struct {

		.seq   = SEQCNT_LOCKTYPE_ZERO(foo.seq, &lock),

		.seq   = SEQCNT_LOCKNAME_ZERO(foo.seq, &lock),

	} foo;



Write path: same as in :ref:`seqcount_t`, while running from a context

with the associated LOCKTYPE lock acquired.

with the associated write serialization lock acquired.



Read path: same as in :ref:`seqcount_t`.