Messages in this thread Patch in this message | | | Date | Thu, 20 Jun 2019 11:55:36 -0400 (EDT) | From | Alan Stern <> | Subject | [PATCH 1/3] tools: memory-model: Expand definition of barrier |
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Commit 66be4e66a7f4 ("rcu: locking and unlocking need to always be at least barriers") added compiler barriers back into rcu_read_lock() and rcu_read_unlock(). Furthermore, srcu_read_lock() and srcu_read_unlock() have always contained compiler barriers.
The Linux Kernel Memory Model ought to know about these barriers. This patch adds them into the memory model.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
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tools/memory-model/linux-kernel.cat | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
Index: usb-devel/tools/memory-model/linux-kernel.cat =================================================================== --- usb-devel.orig/tools/memory-model/linux-kernel.cat +++ usb-devel/tools/memory-model/linux-kernel.cat @@ -47,7 +47,8 @@ let strong-fence = mb | gp let nonrw-fence = strong-fence | po-rel | acq-po let fence = nonrw-fence | wmb | rmb let barrier = fencerel(Barrier | Rmb | Wmb | Mb | Sync-rcu | Sync-srcu | - Before-atomic | After-atomic | Acquire | Release) | + Before-atomic | After-atomic | Acquire | Release | + Rcu-lock | Rcu-unlock | Srcu-lock | Srcu-unlock) | (po ; [Release]) | ([Acquire] ; po) (**********************************)
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