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author | Linus Torvalds <torvalds@linux-foundation.org> | 2023-08-28 18:56:38 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2023-08-28 18:56:38 -0700 |
commit | 815c24a085dd8ab9bb7381e455afdb3f9c260e38 (patch) | |
tree | 46cf481382c497cbbb47de63ca0a75183fc25875 /scripts | |
parent | 5a31cc7297072a7266a910ca5266b640d27803b4 (diff) | |
parent | 25e324bc9cf2ee956eec1db384c39c1a17b7c44a (diff) | |
download | linux-stable-815c24a085dd8ab9bb7381e455afdb3f9c260e38.tar.gz linux-stable-815c24a085dd8ab9bb7381e455afdb3f9c260e38.tar.bz2 linux-stable-815c24a085dd8ab9bb7381e455afdb3f9c260e38.zip |
Merge tag 'linux-kselftest-kunit-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull kunit updates from Shuah Khan:
- add support for running Rust documentation tests as KUnit tests
- make init, str, sync, types doctests compilable/testable
- add support for attributes API which include speed, modules
attributes, ability to filter and report attributes
- add support for marking tests slow using attributes API
- add attributes API documentation
- fix a wild-memory-access bug in kunit_filter_suites() and a possible
memory leak in kunit_filter_suites()
- add support for counting number of test suites in a module, list
action to kunit test modules, and test filtering on module tests
* tag 'linux-kselftest-kunit-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (25 commits)
kunit: fix struct kunit_attr header
kunit: replace KUNIT_TRIGGER_STATIC_STUB maro with KUNIT_STATIC_STUB_REDIRECT
kunit: Allow kunit test modules to use test filtering
kunit: Make 'list' action available to kunit test modules
kunit: Report the count of test suites in a module
kunit: fix uninitialized variables bug in attributes filtering
kunit: fix possible memory leak in kunit_filter_suites()
kunit: fix wild-memory-access bug in kunit_filter_suites()
kunit: Add documentation of KUnit test attributes
kunit: add tests for filtering attributes
kunit: time: Mark test as slow using test attributes
kunit: memcpy: Mark tests as slow using test attributes
kunit: tool: Add command line interface to filter and report attributes
kunit: Add ability to filter attributes
kunit: Add module attribute
kunit: Add speed attribute
kunit: Add test attributes API structure
MAINTAINERS: add Rust KUnit files to the KUnit entry
rust: support running Rust documentation tests as KUnit ones
rust: types: make doctests compilable/testable
...
Diffstat (limited to 'scripts')
-rw-r--r-- | scripts/.gitignore | 2 | ||||
-rw-r--r-- | scripts/Makefile | 4 | ||||
-rw-r--r-- | scripts/rustdoc_test_builder.rs | 72 | ||||
-rw-r--r-- | scripts/rustdoc_test_gen.rs | 260 |
4 files changed, 338 insertions, 0 deletions
diff --git a/scripts/.gitignore b/scripts/.gitignore index 6e9ce6720a05..3dbb8bb2457b 100644 --- a/scripts/.gitignore +++ b/scripts/.gitignore @@ -5,6 +5,8 @@ /kallsyms /module.lds /recordmcount +/rustdoc_test_builder +/rustdoc_test_gen /sign-file /sorttable /target.json diff --git a/scripts/Makefile b/scripts/Makefile index 32b6ba722728..576cf64be667 100644 --- a/scripts/Makefile +++ b/scripts/Makefile @@ -9,6 +9,8 @@ hostprogs-always-$(CONFIG_BUILDTIME_TABLE_SORT) += sorttable hostprogs-always-$(CONFIG_ASN1) += asn1_compiler hostprogs-always-$(CONFIG_MODULE_SIG_FORMAT) += sign-file hostprogs-always-$(CONFIG_SYSTEM_EXTRA_CERTIFICATE) += insert-sys-cert +hostprogs-always-$(CONFIG_RUST_KERNEL_DOCTESTS) += rustdoc_test_builder +hostprogs-always-$(CONFIG_RUST_KERNEL_DOCTESTS) += rustdoc_test_gen always-$(CONFIG_RUST) += target.json filechk_rust_target = $< < include/config/auto.conf @@ -18,6 +20,8 @@ $(obj)/target.json: scripts/generate_rust_target include/config/auto.conf FORCE hostprogs += generate_rust_target generate_rust_target-rust := y +rustdoc_test_builder-rust := y +rustdoc_test_gen-rust := y HOSTCFLAGS_sorttable.o = -I$(srctree)/tools/include HOSTLDLIBS_sorttable = -lpthread diff --git a/scripts/rustdoc_test_builder.rs b/scripts/rustdoc_test_builder.rs new file mode 100644 index 000000000000..e5894652f12c --- /dev/null +++ b/scripts/rustdoc_test_builder.rs @@ -0,0 +1,72 @@ +// SPDX-License-Identifier: GPL-2.0 + +//! Test builder for `rustdoc`-generated tests. +//! +//! This script is a hack to extract the test from `rustdoc`'s output. Ideally, `rustdoc` would +//! have an option to generate this information instead, e.g. as JSON output. +//! +//! The `rustdoc`-generated test names look like `{file}_{line}_{number}`, e.g. +//! `...path_rust_kernel_sync_arc_rs_42_0`. `number` is the "test number", needed in cases like +//! a macro that expands into items with doctests is invoked several times within the same line. +//! +//! However, since these names are used for bisection in CI, the line number makes it not stable +//! at all. In the future, we would like `rustdoc` to give us the Rust item path associated with +//! the test, plus a "test number" (for cases with several examples per item) and generate a name +//! from that. For the moment, we generate ourselves a new name, `{file}_{number}` instead, in +//! the `gen` script (done there since we need to be aware of all the tests in a given file). + +use std::io::Read; + +fn main() { + let mut stdin = std::io::stdin().lock(); + let mut body = String::new(); + stdin.read_to_string(&mut body).unwrap(); + + // Find the generated function name looking for the inner function inside `main()`. + // + // The line we are looking for looks like one of the following: + // + // ``` + // fn main() { #[allow(non_snake_case)] fn _doctest_main_rust_kernel_file_rs_28_0() { + // fn main() { #[allow(non_snake_case)] fn _doctest_main_rust_kernel_file_rs_37_0() -> Result<(), impl core::fmt::Debug> { + // ``` + // + // It should be unlikely that doctest code matches such lines (when code is formatted properly). + let rustdoc_function_name = body + .lines() + .find_map(|line| { + Some( + line.split_once("fn main() {")? + .1 + .split_once("fn ")? + .1 + .split_once("()")? + .0, + ) + .filter(|x| x.chars().all(|c| c.is_alphanumeric() || c == '_')) + }) + .expect("No test function found in `rustdoc`'s output."); + + // Qualify `Result` to avoid the collision with our own `Result` coming from the prelude. + let body = body.replace( + &format!("{rustdoc_function_name}() -> Result<(), impl core::fmt::Debug> {{"), + &format!("{rustdoc_function_name}() -> core::result::Result<(), impl core::fmt::Debug> {{"), + ); + + // For tests that get generated with `Result`, like above, `rustdoc` generates an `unwrap()` on + // the return value to check there were no returned errors. Instead, we use our assert macro + // since we want to just fail the test, not panic the kernel. + // + // We save the result in a variable so that the failed assertion message looks nicer. + let body = body.replace( + &format!("}} {rustdoc_function_name}().unwrap() }}"), + &format!("}} let test_return_value = {rustdoc_function_name}(); assert!(test_return_value.is_ok()); }}"), + ); + + // Figure out a smaller test name based on the generated function name. + let name = rustdoc_function_name.split_once("_rust_kernel_").unwrap().1; + + let path = format!("rust/test/doctests/kernel/{name}"); + + std::fs::write(path, body.as_bytes()).unwrap(); +} diff --git a/scripts/rustdoc_test_gen.rs b/scripts/rustdoc_test_gen.rs new file mode 100644 index 000000000000..5ebd42ae4a3f --- /dev/null +++ b/scripts/rustdoc_test_gen.rs @@ -0,0 +1,260 @@ +// SPDX-License-Identifier: GPL-2.0 + +//! Generates KUnit tests from saved `rustdoc`-generated tests. +//! +//! KUnit passes a context (`struct kunit *`) to each test, which should be forwarded to the other +//! KUnit functions and macros. +//! +//! However, we want to keep this as an implementation detail because: +//! +//! - Test code should not care about the implementation. +//! +//! - Documentation looks worse if it needs to carry extra details unrelated to the piece +//! being described. +//! +//! - Test code should be able to define functions and call them, without having to carry +//! the context. +//! +//! - Later on, we may want to be able to test non-kernel code (e.g. `core`, `alloc` or +//! third-party crates) which likely use the standard library `assert*!` macros. +//! +//! For this reason, instead of the passed context, `kunit_get_current_test()` is used instead +//! (i.e. `current->kunit_test`). +//! +//! Note that this means other threads/tasks potentially spawned by a given test, if failing, will +//! report the failure in the kernel log but will not fail the actual test. Saving the pointer in +//! e.g. a `static` per test does not fully solve the issue either, because currently KUnit does +//! not support assertions (only expectations) from other tasks. Thus leave that feature for +//! the future, which simplifies the code here too. We could also simply not allow `assert`s in +//! other tasks, but that seems overly constraining, and we do want to support them, eventually. + +use std::{ + fs, + fs::File, + io::{BufWriter, Read, Write}, + path::{Path, PathBuf}, +}; + +/// Find the real path to the original file based on the `file` portion of the test name. +/// +/// `rustdoc` generated `file`s look like `sync_locked_by_rs`. Underscores (except the last one) +/// may represent an actual underscore in a directory/file, or a path separator. Thus the actual +/// file might be `sync_locked_by.rs`, `sync/locked_by.rs`, `sync_locked/by.rs` or +/// `sync/locked/by.rs`. This function walks the file system to determine which is the real one. +/// +/// This does require that ambiguities do not exist, but that seems fair, especially since this is +/// all supposed to be temporary until `rustdoc` gives us proper metadata to build this. If such +/// ambiguities are detected, they are diagnosed and the script panics. +fn find_real_path<'a>(srctree: &Path, valid_paths: &'a mut Vec<PathBuf>, file: &str) -> &'a str { + valid_paths.clear(); + + let potential_components: Vec<&str> = file.strip_suffix("_rs").unwrap().split('_').collect(); + + find_candidates(srctree, valid_paths, Path::new(""), &potential_components); + fn find_candidates( + srctree: &Path, + valid_paths: &mut Vec<PathBuf>, + prefix: &Path, + potential_components: &[&str], + ) { + // The base case: check whether all the potential components left, joined by underscores, + // is a file. + let joined_potential_components = potential_components.join("_") + ".rs"; + if srctree + .join("rust/kernel") + .join(prefix) + .join(&joined_potential_components) + .is_file() + { + // Avoid `srctree` here in order to keep paths relative to it in the KTAP output. + valid_paths.push( + Path::new("rust/kernel") + .join(prefix) + .join(joined_potential_components), + ); + } + + // In addition, check whether each component prefix, joined by underscores, is a directory. + // If not, there is no need to check for combinations with that prefix. + for i in 1..potential_components.len() { + let (components_prefix, components_rest) = potential_components.split_at(i); + let prefix = prefix.join(components_prefix.join("_")); + if srctree.join("rust/kernel").join(&prefix).is_dir() { + find_candidates(srctree, valid_paths, &prefix, components_rest); + } + } + } + + assert!( + valid_paths.len() > 0, + "No path candidates found. This is likely a bug in the build system, or some files went \ + away while compiling." + ); + + if valid_paths.len() > 1 { + eprintln!("Several path candidates found:"); + for path in valid_paths { + eprintln!(" {path:?}"); + } + panic!( + "Several path candidates found, please resolve the ambiguity by renaming a file or \ + folder." + ); + } + + valid_paths[0].to_str().unwrap() +} + +fn main() { + let srctree = std::env::var("srctree").unwrap(); + let srctree = Path::new(&srctree); + + let mut paths = fs::read_dir("rust/test/doctests/kernel") + .unwrap() + .map(|entry| entry.unwrap().path()) + .collect::<Vec<_>>(); + + // Sort paths. + paths.sort(); + + let mut rust_tests = String::new(); + let mut c_test_declarations = String::new(); + let mut c_test_cases = String::new(); + let mut body = String::new(); + let mut last_file = String::new(); + let mut number = 0; + let mut valid_paths: Vec<PathBuf> = Vec::new(); + let mut real_path: &str = ""; + for path in paths { + // The `name` follows the `{file}_{line}_{number}` pattern (see description in + // `scripts/rustdoc_test_builder.rs`). Discard the `number`. + let name = path.file_name().unwrap().to_str().unwrap().to_string(); + + // Extract the `file` and the `line`, discarding the `number`. + let (file, line) = name.rsplit_once('_').unwrap().0.rsplit_once('_').unwrap(); + + // Generate an ID sequence ("test number") for each one in the file. + if file == last_file { + number += 1; + } else { + number = 0; + last_file = file.to_string(); + + // Figure out the real path, only once per file. + real_path = find_real_path(srctree, &mut valid_paths, file); + } + + // Generate a KUnit name (i.e. test name and C symbol) for this test. + // + // We avoid the line number, like `rustdoc` does, to make things slightly more stable for + // bisection purposes. However, to aid developers in mapping back what test failed, we will + // print a diagnostics line in the KTAP report. + let kunit_name = format!("rust_doctest_kernel_{file}_{number}"); + + // Read the test's text contents to dump it below. + body.clear(); + File::open(path).unwrap().read_to_string(&mut body).unwrap(); + + // Calculate how many lines before `main` function (including the `main` function line). + let body_offset = body + .lines() + .take_while(|line| !line.contains("fn main() {")) + .count() + + 1; + + use std::fmt::Write; + write!( + rust_tests, + r#"/// Generated `{name}` KUnit test case from a Rust documentation test. +#[no_mangle] +pub extern "C" fn {kunit_name}(__kunit_test: *mut kernel::bindings::kunit) {{ + /// Overrides the usual [`assert!`] macro with one that calls KUnit instead. + #[allow(unused)] + macro_rules! assert {{ + ($cond:expr $(,)?) => {{{{ + kernel::kunit_assert!("{kunit_name}", "{real_path}", __DOCTEST_ANCHOR - {line}, $cond); + }}}} + }} + + /// Overrides the usual [`assert_eq!`] macro with one that calls KUnit instead. + #[allow(unused)] + macro_rules! assert_eq {{ + ($left:expr, $right:expr $(,)?) => {{{{ + kernel::kunit_assert_eq!("{kunit_name}", "{real_path}", __DOCTEST_ANCHOR - {line}, $left, $right); + }}}} + }} + + // Many tests need the prelude, so provide it by default. + #[allow(unused)] + use kernel::prelude::*; + + // Unconditionally print the location of the original doctest (i.e. rather than the location in + // the generated file) so that developers can easily map the test back to the source code. + // + // This information is also printed when assertions fail, but this helps in the successful cases + // when the user is running KUnit manually, or when passing `--raw_output` to `kunit.py`. + // + // This follows the syntax for declaring test metadata in the proposed KTAP v2 spec, which may + // be used for the proposed KUnit test attributes API. Thus hopefully this will make migration + // easier later on. + kernel::kunit::info(format_args!(" # {kunit_name}.location: {real_path}:{line}\n")); + + /// The anchor where the test code body starts. + #[allow(unused)] + static __DOCTEST_ANCHOR: i32 = core::line!() as i32 + {body_offset} + 1; + {{ + {body} + main(); + }} +}} + +"# + ) + .unwrap(); + + write!(c_test_declarations, "void {kunit_name}(struct kunit *);\n").unwrap(); + write!(c_test_cases, " KUNIT_CASE({kunit_name}),\n").unwrap(); + } + + let rust_tests = rust_tests.trim(); + let c_test_declarations = c_test_declarations.trim(); + let c_test_cases = c_test_cases.trim(); + + write!( + BufWriter::new(File::create("rust/doctests_kernel_generated.rs").unwrap()), + r#"//! `kernel` crate documentation tests. + +const __LOG_PREFIX: &[u8] = b"rust_doctests_kernel\0"; + +{rust_tests} +"# + ) + .unwrap(); + + write!( + BufWriter::new(File::create("rust/doctests_kernel_generated_kunit.c").unwrap()), + r#"/* + * `kernel` crate documentation tests. + */ + +#include <kunit/test.h> + +{c_test_declarations} + +static struct kunit_case test_cases[] = {{ + {c_test_cases} + {{ }} +}}; + +static struct kunit_suite test_suite = {{ + .name = "rust_doctests_kernel", + .test_cases = test_cases, +}}; + +kunit_test_suite(test_suite); + +MODULE_LICENSE("GPL"); +"# + ) + .unwrap(); +} |