Commit Graph

7 Commits

Author SHA1 Message Date
Willy Tarreau
4a95be7ed7 selftests/nolibc: Always rebuild the sysroot when running a test
Paul and I got trapped a few times by not seeing the effects of applying
a patch to the nolibc source code until a "make clean" was issued in
the nolibc directory. It's particularly annoying when trying to confirm
that a proposed patch really solves a problem (or that reverting it
reintroduces the problem).

The reason for the sysroot not being rebuilt was that it can be quite
slow. But in fact it's only slow after a "make clean" issued at the
kernel's topdir, because it's the main "make headers" that can take a
tens of seconds; as long as "usr/include" still contains headers, the
"headers_install" phase is only a quick "rsync", and rebuilding the
whole nolibc sysroot takes a bit less than one second, which is perfectly
acceptable for a test, even more once the time lost caused by misleading
results is factored in.

This patch marks the sysroot target as phony and starts by clearing
the previous sysroot for the current architecture before reinstalling
it. Thanks to this, applying a patch to nolibc makes the effect
immediately visible to "make nolibc-test":

  $ time make -j -C tools/testing/selftests/nolibc nolibc-test
  make: Entering directory '/k/tools/testing/selftests/nolibc'
    MKDIR   sysroot/x86/include
  make[1]: Entering directory '/k/tools/include/nolibc'
  make[2]: Entering directory '/k'
  make[2]: Leaving directory '/k'
  make[2]: Entering directory '/k'
    INSTALL /k/tools/testing/selftests/nolibc/sysroot/sysroot/include
  make[2]: Leaving directory '/k'
  make[1]: Leaving directory '/k/tools/include/nolibc'
    CC      nolibc-test
  make: Leaving directory '/k/tools/testing/selftests/nolibc'

  real    0m0.869s
  user    0m0.716s
  sys     0m0.149s

Cc: "Paul E. McKenney" <paulmck@kernel.org>
Link: https://lore.kernel.org/all/20221021155645.GK5600@paulmck-ThinkPad-P17-Gen-1/
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-10-28 15:17:22 -07:00
Willy Tarreau
ffc297fe22 selftests/nolibc: add a "help" target
It presents the supported targets, and becomes the default target to
save the user from having to read the makefile. The "all" target was
placed after it and now points to "run" to do everything since it's
no longer the default one.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31 05:17:45 -07:00
Willy Tarreau
b25c5284db selftests/nolibc: "sysroot" target installs a local copy of the sysroot
It's not convenient to rely on a sysroot built in another directory,
especially when running cross-compilation tests, where one has to
switch back and forth between directories.

Let's make it possible to install the sysroot directly in the test
directory. It's not big and even benefits from being copied by arch
so that it's easier to switch between archs if needed. The new
"sysroot" target does this, it just calls "headers_standalone" from
nolibc to install the sysroot right here.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31 05:17:45 -07:00
Willy Tarreau
662ea60e37 selftests/nolibc: add a "run" target to start the kernel in QEMU
The "run" target will build the kernel and start it in QEMU. The
"rerun" target will not have the kernel dependency and will just try
to start QEMU. The QEMU architecture used to start the kernel is
derived from the configured ARCH. This might need to be improved
for archs which include different variants under the same name
(mips vs mipsel, +/-64, riscv32 vs riscv64). This could be tested
for i386, x86, arm, arm64, mips and riscv (the later two reporting
issues on some tests).

It is possible to pass a test specification for nolibc-test in the TEST
variable, which will be passed as-is as NOLIBC_TEST.

On success, the number of successful tests is printed. On failure, failed
lines are individually printed.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31 05:17:45 -07:00
Willy Tarreau
5c43fd7954 selftests/nolibc: add a "defconfig" target
While most archs will work fine with "make defconfig", not all will
do, and it's not always easy to remember the most suitable choice to
use for a specific architecture.

This adds a "defconfig" target to the Makefile so that one may easily
run "make -C ... defconfig" and make sure to clean and rebuild a fresh
config. This is *not* used by default because we want to preserve the
user's config by default.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31 05:17:45 -07:00
Willy Tarreau
d248cabff5 selftests/nolibc: add a "kernel" target to build the kernel with the initramfs
The "kernel" target rebuilds the kernel with the current config for the
selected arch, with an initramfs containing the nolibc-test utility.

Since image names depend on the architecture, the currently supported
ones are referenced and resolved based on the architecture.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31 05:17:45 -07:00
Willy Tarreau
362aecb2d8 selftests/nolibc: add basic infrastructure to ease creation of nolibc tests
This creates a "nolibc" selftest that intends to test various parts of
the nolibc component, both in terms of build and execution for a given
architecture.

The aim is for it to be as simple to run as a kernel build, by just
passing the compiler (for the build) and the ARCH (for kernel and
execution).

It brings a basic squeleton made of a single C file that will ease testing
and error reporting. The code will be arranged so that it remains easy to
add basic tests for syscalls or library calls that may rely on a condition
to be executed, and whose result is compared to a value or to an error
with a specific errno value.

Tests will just use a relative line number in switch/case statements as
an index, saving the user from having to maintain arrays and complicated
functions which can often just be one-liners.

MAINTAINERS was updated.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31 05:17:44 -07:00