kernel/linux.git/tools/memory-model, branch v6.19.11

tools/memory-model/Documentation: Fix SRCU section in explanation.txt

2025-04-23T19:17:04+00:00

The SRCU read-side critical sections describes the difference between srcu_down_read()/srcu_up_read() and srcu_read_lock()/srcu_read_unlock() in a way that a last pair must occur on the same CPU. This is not true, the srcu_read_unlock() can happen on any CPU, but it must be performed by the same task that invoked srcu_read_lock(). Signed-off-by: Uladzislau Rezki (Sony) Signed-off-by: Paul E. McKenney

tools/memory-model: docs/references: Remove broken link to imgtec.com

2025-04-22T18:22:05+00:00

MIPS documents are not provided at imgtec.com any more. Get rid of useless link. Signed-off-by: Akira Yokosawa Signed-off-by: Paul E. McKenney Acked-by: Andrea Parri

tools/memory-model: docs/ordering: Fix trivial typos

2025-04-22T18:22:01+00:00

Fix trivial typos including: - Repeated "a call to" - Inconsistent forms of referencing functions of rcu_dereference() and rcu_assign_pointer() - Past tense used in describing normal behavior and other minor ones. [ paulmck: Wordsmith plus recent LWN RCU API URL. ] Signed-off-by: Akira Yokosawa Signed-off-by: Paul E. McKenney Acked-by: Andrea Parri

tools/memory-model: docs/simple.txt: Fix trivial typos

2025-04-22T18:21:56+00:00

Signed-off-by: Akira Yokosawa Signed-off-by: Paul E. McKenney Acked-by: Andrea Parri

tools/memory-model: docs/README: Update introduction of locking.txt

2025-04-22T18:21:46+00:00

Commit 9bc931e9e161 ("tools/memory-model: Add locking.txt and glossary.txt to README") failed to mention the relation of the "Locking" section in recipes.txt and locking.txt. The latter is a detailed version of the former intended to be read on its own. Reword the description in README and add notes in locking.txt and recipes.txt to clarify their relationship. [ paulmck: Wordsmithing. ] Signed-off-by: Akira Yokosawa Signed-off-by: Paul E. McKenney Acked-by: Andrea Parri

tools/memory-model: glossary.txt: Fix indents

2025-02-25T18:22:34+00:00

There are a couple of inconsistent indents around code/literal blocks. Adjust them to make this file easier to parse. Signed-off-by: Akira Yokosawa Signed-off-by: Paul E. McKenney

tools/memory-model/README: Fix typo

2025-02-25T18:22:34+00:00

Fix a trivial typo. Signed-off-by: Akira Yokosawa Signed-off-by: Paul E. McKenney

tools/memory-model: Distinguish between syntactic and semantic tags

2025-02-25T18:17:39+00:00

Not all annotated accesses provide the semantics their syntactic tags would imply. For example, an 'acquire tag on a write does not imply that the write is finally in the Acquire set and provides acquire ordering. To distinguish in those cases between the syntactic tags and actual sets, we capitalize the former, so 'ACQUIRE tags may be present on both reads and writes, but only reads will appear in the Acquire set. For tags where the two concepts are the same we do not use specific capitalization to make this distinction. Reported-by: Boqun Feng Signed-off-by: Jonas Oberhauser Reviewed-by: Boqun Feng Tested-by: Boqun Feng Signed-off-by: Paul E. McKenney Tested-by: Akira Yokosawa # herdtools7.7.58

tools/memory-model: Switch to softcoded herd7 tags

2025-02-25T18:16:57+00:00

A new version of herd7 provides a -lkmmv2 switch which overrides the old herd7 behavior of simply ignoring any softcoded tags in the .def and .bell files. We port LKMM to this version of herd7 by providing the switch in linux-kernel.cfg and reporting an error if the LKMM is used without this switch. To preserve the semantics of LKMM, we also softcode the Noreturn tag on atomic RMW which do not return a value and define atomic_add_unless with an Mb tag in linux-kernel.def. We update the herd-representation.txt accordingly and clarify some of the resulting combinations. Co-developed-by: Hernan Ponce de Leon Signed-off-by: Hernan Ponce de Leon Signed-off-by: Jonas Oberhauser Signed-off-by: Paul E. McKenney Reviewed-by: Boqun Feng Tested-by: Boqun Feng Tested-by: Akira Yokosawa # herdtools7.7.58

tools/memory-model: Define effect of Mb tags on RMWs in tools/...

2025-02-20T15:40:23+00:00

Herd7 transforms successful RMW with Mb tags by inserting smp_mb() fences around them. We emulate this by considering imaginary po-edges before the RMW read and before the RMW write, and extending the smp_mb() ordering rule, which currently only applies to real po edges that would be found around a really inserted smp_mb(), also to cases of the only imagined po edges. Reported-by: Viktor Vafeiadis Suggested-by: Alan Stern Signed-off-by: Jonas Oberhauser Signed-off-by: Paul E. McKenney Reviewed-by: Boqun Feng Tested-by: Boqun Feng