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author | Boqun Feng <boqun.feng@gmail.com> | 2020-03-26 10:40:19 +0800 |
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committer | Paul E. McKenney <paulmck@kernel.org> | 2020-06-29 12:05:18 -0700 |
commit | 4a9cc65f7a715ba1f4f58529f7bf6f1548d8701f (patch) | |
tree | d6fc4aaacde29c628c97f78d2bb21cb4ba726d7d /tools | |
parent | 7f871338ff939952c4e04a83ae395ff9d57040c2 (diff) | |
download | linux-4a9cc65f7a715ba1f4f58529f7bf6f1548d8701f.tar.bz2 |
tools/memory-model: Add an exception for limitations on _unless() family
According to Luc, atomic_add_unless() is directly provided by herd7,
therefore it can be used in litmus tests. So change the limitation
section in README to unlimit the use of atomic_add_unless().
Cc: Luc Maranget <luc.maranget@inria.fr>
Acked-by: Andrea Parri <parri.andrea@gmail.com>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'tools')
-rw-r--r-- | tools/memory-model/README | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/tools/memory-model/README b/tools/memory-model/README index fc07b52f2028..b9c562e92981 100644 --- a/tools/memory-model/README +++ b/tools/memory-model/README @@ -207,11 +207,15 @@ The Linux-kernel memory model (LKMM) has the following limitations: case as a store release. b. The "unless" RMW operations are not currently modeled: - atomic_long_add_unless(), atomic_add_unless(), - atomic_inc_unless_negative(), and - atomic_dec_unless_positive(). These can be emulated + atomic_long_add_unless(), atomic_inc_unless_negative(), + and atomic_dec_unless_positive(). These can be emulated in litmus tests, for example, by using atomic_cmpxchg(). + One exception of this limitation is atomic_add_unless(), + which is provided directly by herd7 (so no corresponding + definition in linux-kernel.def). atomic_add_unless() is + modeled by herd7 therefore it can be used in litmus tests. + c. The call_rcu() function is not modeled. It can be emulated in litmus tests by adding another process that invokes synchronize_rcu() and the body of the callback |