On Wed, Jul 16, 2025 at 02:47:13PM +0200, Peter Zijlstra wrote:
On Wed, Jul 16, 2025 at 11:23:09AM +0200, Greg Kroah-Hartman wrote:
quoted
On Sun, Jul 13, 2025 at 10:36:48PM -0700, Boqun Feng wrote:
quoted
In order to support LKMM atomics in Rust, add rust_helper_* for atomic
APIs. These helpers ensure the implementation of LKMM atomics in Rust is
the same as in C. This could save the maintenance burden of having two
similar atomic implementations in asm.
Originally-by: Mark Rutland [off-list ref]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Boqun Feng <redacted>
---
rust/helpers/atomic.c | 1040 +++++++++++++++++++++
rust/helpers/helpers.c | 1 +
scripts/atomic/gen-atomics.sh | 1 +
scripts/atomic/gen-rust-atomic-helpers.sh | 67 ++
4 files changed, 1109 insertions(+)
create mode 100644 rust/helpers/atomic.c
create mode 100755 scripts/atomic/gen-rust-atomic-helpers.sh
diff --git a/rust/helpers/atomic.c b/rust/helpers/atomic.c
new file mode 100644
index 000000000000..cf06b7ef9a1c
--- /dev/null
+++ b/rust/helpers/atomic.c
@@ -0,0 +1,1040 @@
+// SPDX-License-Identifier: GPL-2.0
+
+// Generated by scripts/atomic/gen-rust-atomic-helpers.sh
+// DO NOT MODIFY THIS FILE DIRECTLY
As this is auto-generated, how do we know when to auto-generate it
again? What files does it depend on? And why can't we just
auto-generate it at build time instead of having a static file in the
tree that no one knows when to regenerate it? :)
It depends on the scripts/atomic/* bits. They hardly if ever change. We
do it this way because:
- generating these files every build is 'slow'-ish;
- code navigation suffers;
- Linus asked for this.
Specifically, pretty much the entire atomic_*() namespace would
disappear from ctags / code-browsing-tool-of-choice if we would not
check in these files.
Ah, ok, that makes sense in a sad way. As long as someone knows to
regenerate these files when needed, hopefully when the C files change
someone knows to update these rust ones...
thanks,
greg k-h