[PATCH 0/3] rust: more memory barriers bindings

From: Gary Guo <[email protected]>

This expands the existing smp barriers to also mandatory barriers and
DMA barriers.

The API looks like:
`mb(Ordering)`/`smp_mb(Ordering)`/`dma_mb(Ordering)`, where `Ordering`
is one of `Full`, `Read`, `Write` and also `Acquire`, `Release`.

The `Acquire` and `Release` barriers are mapped to `Full` barriers for
now and they only serve the purpose of documenting what ordering is
needed without codegen optimizations, but they could be improved
later to produce better codegen compared to full barriers. More on them
in the commit message of patch 2.

A user of these introduced API is included in patch 3, which is a
concurrency bug that exists in Nova code today due to missing barriers.

To: Miguel Ojeda <[email protected]>
To: Boqun Feng <[email protected]>
To: Danilo Krummrich <[email protected]>
To: Alexandre Courbot <[email protected]>
Cc: Björn Roy Baron <[email protected]>
Cc: Benno Lossin <[email protected]>
Cc: Andreas Hindborg <[email protected]>
Cc: Alice Ryhl <[email protected]>
Cc: Trevor Gross <[email protected]>
Cc: Alan Stern <[email protected]>
Cc: Andrea Parri <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Nicholas Piggin <[email protected]>
Cc: David Howells <[email protected]>
Cc: Jade Alglave <[email protected]>
Cc: Luc Maranget <[email protected]>
Cc: "Paul E. McKenney" <[email protected]>
Cc: Akira Yokosawa <[email protected]>
Cc: Daniel Lustig <[email protected]>
Cc: Joel Fernandes <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]

Gary Guo (3):
  rust: sync: add helpers for mb, dma_mb and friends
  rust: sync: generic memory barriers
  gpu: nova-core: fix wrong use of barriers in GSP code

 drivers/gpu/nova-core/gsp/cmdq.rs   |  19 +++
 drivers/gpu/nova-core/gsp/fw.rs     |  12 --
 rust/helpers/barrier.c              |  30 +++++
 rust/kernel/sync/atomic/ordering.rs |   2 +-
 rust/kernel/sync/barrier.rs         | 194 ++++++++++++++++++++++++----
 5 files changed, 217 insertions(+), 40 deletions(-)


base-commit: 36ece9697e89016181e5ae87510e40fb31d86f2b
-- 
2.51.2