On Fri, Jun 28, 2024 at 01:23:32PM +0000, Alice Ryhl wrote:
quoted hunk ↗ jump to hunk
Make it possible to have Rust code call into tracepoints defined by C
code. It is still required that the tracepoint is declared in a C
header, and that this header is included in the input to bindgen.
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
---
include/linux/tracepoint.h | 18 +++++++++++++++-
include/trace/define_trace.h | 12 +++++++++++
rust/bindings/bindings_helper.h | 1 +
rust/kernel/lib.rs | 1 +
rust/kernel/tracepoint.rs | 47 +++++++++++++++++++++++++++++++++++++++++
5 files changed, 78 insertions(+), 1 deletion(-)
diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h
index 689b6d71590e..d82af4d77c9f 100644
--- a/include/linux/tracepoint.h
+++ b/include/linux/tracepoint.h
@@ -238,6 +238,20 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p)
#define __DECLARE_TRACE_RCU(name, proto, args, cond)
#endif
+/*
+ * Declare an exported function that Rust code can call to trigger this
+ * tracepoint. This function does not include the static branch; that is done
+ * in Rust to avoid a function call when the tracepoint is disabled.
+ */
+#define DEFINE_RUST_DO_TRACE(name, proto, args)
+#define DEFINE_RUST_DO_TRACE_REAL(name, proto, args) \
nit: IMO using a __* prefix would be a better option to describe the
internal use of the macro instead of the _REAL suffix.
Other than that, this patch looks good to me:
Reviewed-by: Carlos Llamas <cmllamas@google.com>