[PATCH v3] scripts: `make rust-analyzer` for out-of-tree modules

From: Vinay Varma
Date: Tue Mar 07 2023 - 10:00:48 EST


Adds support for out-of-tree rust modules to use the `rust-analyzer`
make target to generate the rust-project.json file.

The change involves adding an optional parameter `external_src` to the
`generate_rust_analyzer.py` which expects the path to the out-of-tree
module's source directory. When this parameter is passed, I have chosen
not to add the non-core modules (samples and drivers) into the result
since these are not expected to be used in third party modules. Related
changes are also made to the Makefile and rust/Makefile allowing the
`rust-analyzer` target to be used for out-of-tree modules as well.

Link: https://github.com/Rust-for-Linux/linux/pull/914
Link: https://github.com/Rust-for-Linux/rust-out-of-tree-module/pull/2

Signed-off-by: Vinay Varma <varmavinaym@xxxxxxxxx>
---
Makefile | 11 ++++++-----
rust/Makefile | 6 ++++--
scripts/generate_rust_analyzer.py | 31 ++++++++++++++++++-------------
3 files changed, 28 insertions(+), 20 deletions(-)

diff --git a/Makefile b/Makefile
index 3f6628780eb2..ee7b61dc6075 100644
--- a/Makefile
+++ b/Makefile
@@ -1860,11 +1860,6 @@ rustfmt:
rustfmtcheck: rustfmt_flags = --check
rustfmtcheck: rustfmt

-# IDE support targets
-PHONY += rust-analyzer
-rust-analyzer:
- $(Q)$(MAKE) $(build)=rust $@
-
# Misc
# ---------------------------------------------------------------------------

@@ -1917,6 +1912,7 @@ help:
@echo ' modules - default target, build the module(s)'
@echo ' modules_install - install the module'
@echo ' clean - remove generated files in module directory only'
+ @echo ' rust-analyzer - generate rust-project.json rust-analyzer support file'
@echo ''

endif # KBUILD_EXTMOD
@@ -2053,6 +2049,11 @@ quiet_cmd_tags = GEN $@
tags TAGS cscope gtags: FORCE
$(call cmd,tags)

+# IDE support targets
+PHONY += rust-analyzer
+rust-analyzer:
+ $(Q)$(MAKE) $(build)=rust $@
+
# Script to generate missing namespace dependencies
# ---------------------------------------------------------------------------

diff --git a/rust/Makefile b/rust/Makefile
index 8f598a904f38..41c1435cd8d4 100644
--- a/rust/Makefile
+++ b/rust/Makefile
@@ -389,8 +389,10 @@ quiet_cmd_rustc_library = $(if $(skip_clippy),RUSTC,$(RUSTC_OR_CLIPPY_QUIET)) L
$(if $(rustc_objcopy),;$(OBJCOPY) $(rustc_objcopy) $@)

rust-analyzer:
- $(Q)$(srctree)/scripts/generate_rust_analyzer.py $(srctree) $(objtree) \
- $(RUST_LIB_SRC) > $(objtree)/rust-project.json
+ $(Q)$(srctree)/scripts/generate_rust_analyzer.py \
+ $(abs_srctree) $(abs_objtree) \
+ $(RUST_LIB_SRC) $(KBUILD_EXTMOD) > \
+ $(if $(KBUILD_EXTMOD),$(extmod_prefix),$(objtree))/rust-project.json

$(obj)/core.o: private skip_clippy = 1
$(obj)/core.o: private skip_flags = -Dunreachable_pub
diff --git a/scripts/generate_rust_analyzer.py b/scripts/generate_rust_analyzer.py
index ecc7ea9a4dcf..741ccd6efe2b 100755
--- a/scripts/generate_rust_analyzer.py
+++ b/scripts/generate_rust_analyzer.py
@@ -6,10 +6,11 @@
import argparse
import json
import logging
+import os
import pathlib
import sys

-def generate_crates(srctree, objtree, sysroot_src):
+def generate_crates(srctree, objtree, sysroot_src, external_src):
# Generate the configuration list.
cfg = []
with open(objtree / "include" / "generated" / "rustc_cfg") as fd:
@@ -65,7 +66,7 @@ def generate_crates(srctree, objtree, sysroot_src):
[],
is_proc_macro=True,
)
- crates[-1]["proc_macro_dylib_path"] = "rust/libmacros.so"
+ crates[-1]["proc_macro_dylib_path"] = f"{objtree}/rust/libmacros.so"

append_crate(
"build_error",
@@ -95,25 +96,28 @@ def generate_crates(srctree, objtree, sysroot_src):
"exclude_dirs": [],
}

+ def is_root_crate(build_file, target):
+ return os.path.exists(build_file) and target in open(build_file).read()
+
# Then, the rest outside of `rust/`.
#
# We explicitly mention the top-level folders we want to cover.
- for folder in ("samples", "drivers"):
+ for folder in ("samples", "drivers") if external_src is None else [external_src]:
for path in (srctree / folder).rglob("*.rs"):
logging.info("Checking %s", path)
name = path.name.replace(".rs", "")

# Skip those that are not crate roots.
- if f"{name}.o" not in open(path.parent / "Makefile").read():
- continue
+ if is_root_crate(path.parent / "Makefile", f"{name}.o") or \
+ is_root_crate(path.parent / "Kbuild", f"{name}.o"):

- logging.info("Adding %s", name)
- append_crate(
- name,
- path,
- ["core", "alloc", "kernel"],
- cfg=cfg,
- )
+ logging.info("Adding %s", name)
+ append_crate(
+ name,
+ path,
+ ["core", "alloc", "kernel"],
+ cfg=cfg,
+ )

return crates

@@ -123,6 +127,7 @@ def main():
parser.add_argument("srctree", type=pathlib.Path)
parser.add_argument("objtree", type=pathlib.Path)
parser.add_argument("sysroot_src", type=pathlib.Path)
+ parser.add_argument("exttree", type=pathlib.Path, nargs="?")
args = parser.parse_args()

logging.basicConfig(
@@ -131,7 +136,7 @@ def main():
)

rust_project = {
- "crates": generate_crates(args.srctree, args.objtree, args.sysroot_src),
+ "crates": generate_crates(args.srctree, args.objtree, args.sysroot_src, args.exttree),
"sysroot_src": str(args.sysroot_src),
}

--
2.39.2