On Thu, Aug 22, 2024 at 12:04:15PM +0000, Alice Ryhl wrote: > This updates the Rust printing sample to invoke a tracepoint. This > ensures that we have a user in-tree from the get-go even though the > patch is being merged before its real user. > > Signed-off-by: Alice Ryhl <aliceryhl@xxxxxxxxxx> > --- > MAINTAINERS | 1 + > include/trace/events/rust_sample.h | 31 +++++++++++++++++++++++++++++++ > rust/bindings/bindings_helper.h | 1 + > samples/rust/Makefile | 3 ++- > samples/rust/rust_print.rs | 18 ++++++++++++++++++ > samples/rust/rust_print_events.c | 8 ++++++++ > 6 files changed, 61 insertions(+), 1 deletion(-) > > diff --git a/MAINTAINERS b/MAINTAINERS > index f328373463b0..1acf5bfddfc4 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -19922,6 +19922,7 @@ C: zulip://rust-for-linux.zulipchat.com > P: https://rust-for-linux.com/contributing > T: git https://github.com/Rust-for-Linux/linux.git rust-next > F: Documentation/rust/ > +F: include/trace/events/rust_sample.h > F: rust/ > F: samples/rust/ > F: scripts/*rust* > diff --git a/include/trace/events/rust_sample.h b/include/trace/events/rust_sample.h > new file mode 100644 > index 000000000000..dbc80ca2e465 > --- /dev/null > +++ b/include/trace/events/rust_sample.h Is it possible to make this a header file inside sample/rust/? Given this is just an example, I feel it's better if we could avoid making this "public", but maybe I'm missing some constraints of tracepoints. (Oh, I just remember the problem while I was writting this: we need the header file here because this is now how bindgen generates bindings, so moving it to sample/rust/ requires we have "per-module" or "per-subsystem" bindgen feature) Anyway this is not a big deal to me. We can move it later if possible. So: Reviewed-by: Boqun Feng <boqun.feng@xxxxxxxxx> Regards, Boqun > @@ -0,0 +1,31 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/* > + * Tracepoints for `samples/rust/rust_print.rs`. > + * > + * Copyright (C) 2024 Google, Inc. > + */ > + > +#undef TRACE_SYSTEM > +#define TRACE_SYSTEM rust_sample > + > +#if !defined(_RUST_SAMPLE_TRACE_H) || defined(TRACE_HEADER_MULTI_READ) > +#define _RUST_SAMPLE_TRACE_H > + > +#include <linux/tracepoint.h> > + > +TRACE_EVENT(rust_sample_loaded, > + TP_PROTO(int magic_number), > + TP_ARGS(magic_number), > + TP_STRUCT__entry( > + __field(int, magic_number) > + ), > + TP_fast_assign( > + __entry->magic_number = magic_number; > + ), > + TP_printk("magic=%d", __entry->magic_number) > +); > + > +#endif /* _RUST_SAMPLE_TRACE_H */ > + > +/* This part must be outside protection */ > +#include <trace/define_trace.h> > diff --git a/rust/bindings/bindings_helper.h b/rust/bindings/bindings_helper.h > index fc6f94729789..fe97256afe65 100644 > --- a/rust/bindings/bindings_helper.h > +++ b/rust/bindings/bindings_helper.h > @@ -23,6 +23,7 @@ > #include <linux/tracepoint.h> > #include <linux/wait.h> > #include <linux/workqueue.h> > +#include <trace/events/rust_sample.h> > > /* `bindgen` gets confused at certain things. */ > const size_t RUST_CONST_HELPER_ARCH_SLAB_MINALIGN = ARCH_SLAB_MINALIGN; > diff --git a/samples/rust/Makefile b/samples/rust/Makefile > index 03086dabbea4..f29280ec4820 100644 > --- a/samples/rust/Makefile > +++ b/samples/rust/Makefile > @@ -1,6 +1,7 @@ > # SPDX-License-Identifier: GPL-2.0 > +ccflags-y += -I$(src) # needed for trace events > > obj-$(CONFIG_SAMPLE_RUST_MINIMAL) += rust_minimal.o > -obj-$(CONFIG_SAMPLE_RUST_PRINT) += rust_print.o > +obj-$(CONFIG_SAMPLE_RUST_PRINT) += rust_print.o rust_print_events.o > > subdir-$(CONFIG_SAMPLE_RUST_HOSTPROGS) += hostprogs > diff --git a/samples/rust/rust_print.rs b/samples/rust/rust_print.rs > index 6eabb0d79ea3..6d14b08cac1c 100644 > --- a/samples/rust/rust_print.rs > +++ b/samples/rust/rust_print.rs > @@ -69,6 +69,8 @@ fn init(_module: &'static ThisModule) -> Result<Self> { > > arc_print()?; > > + trace::trace_rust_sample_loaded(42); > + > Ok(RustPrint) > } > } > @@ -78,3 +80,19 @@ fn drop(&mut self) { > pr_info!("Rust printing macros sample (exit)\n"); > } > } > + > +mod trace { > + use core::ffi::c_int; > + > + kernel::declare_trace! { > + /// # Safety > + /// > + /// Always safe to call. > + unsafe fn rust_sample_loaded(magic: c_int); > + } > + > + pub(crate) fn trace_rust_sample_loaded(magic: i32) { > + // SAFETY: Always safe to call. > + unsafe { rust_sample_loaded(magic as c_int) } > + } > +} > diff --git a/samples/rust/rust_print_events.c b/samples/rust/rust_print_events.c > new file mode 100644 > index 000000000000..a9169ff0edf1 > --- /dev/null > +++ b/samples/rust/rust_print_events.c > @@ -0,0 +1,8 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright 2024 Google LLC > + */ > + > +#define CREATE_TRACE_POINTS > +#define CREATE_RUST_TRACE_POINTS > +#include <trace/events/rust_sample.h> > > -- > 2.46.0.184.g6999bdac58-goog >
