August 2025 - Linux-kselftest-mirror

[PATCH v3 0/7] kunit: Refactor and extend KUnit's parameterized testing framework

by Marie Zhussupova

Hello! KUnit offers a parameterized testing framework, where tests can be run multiple times with different inputs. However, the current implementation uses the same `struct kunit` for each parameter run. After each run, the test context gets cleaned up, which creates the following limitations: a. There is no way to store resources that are accessible across the individual parameter runs. b. It's not possible to pass additional context, besides the previous parameter (and potentially anything else that is stored in the current test context), to the parameter generator function. c. Test users are restricted to using pre-defined static arrays of parameter objects or generate_params() to define their parameters. There is no flexibility to make a custom dynamic array without using generate_params(), which can be complex if generating the next parameter depends on more than just the single previous parameter. This patch series resolves these limitations by: 1. [P 1] Giving each parameterized run its own `struct kunit`. It will remove the need to manage state, such as resetting the `test->priv` field or the `test->status_comment` after every parameter run. 2. [P 1] Introducing parameterized test context available to all parameter runs through the parent pointer of type `struct kunit`. This context won't be used to execute any test logic, but will instead be used for storing shared resources. Each parameter run context will have a reference to that parent instance and thus, have access to those resources. 3. [P 2] Introducing param_init() and param_exit() functions that can initialize and exit the parameterized test context. They will run once before and after the parameterized test. param_init() can be used to add resources to share between parameter runs, pass parameter arrays, and any other setup logic. While param_exit() can be used to clean up resources that were not managed by the parameterized test, and any other teardown logic. 4. [P 3] Passing the parameterized test context as an additional argument to generate_params(). This provides generate_params() with more context, making parameter generation much more flexible. The generate_params() implementations in the KCSAN and drm/xe tests have been adapted to match the new function pointer signature. 5. [P 4] Introducing a `params_array` field in `struct kunit`. This will allow the parameterized test context to have direct storage of the parameter array, enabling features like using dynamic parameter arrays or using context beyond just the previous parameter. This will also enable outputting the KTAP test plan for a parameterized test when the parameter count is available. Patches 5 and 6 add examples tests to lib/kunit/kunit-example-test.c to showcase the new features and patch 7 updates the KUnit documentation to reflect all the framework changes. Thank you! -Marie --- Changes in v3: Link to v2 of this patch series: https://lore.kernel.org/all/20250811221739.2694336-1-marievic@google.com/ - Added logic for skipping the parameter runs and updating the test statistics when parameterized test initialization fails. - Minor changes to the documentation. - Commit message formatting. Changes in v2: Link to v1 of this patch series: https://lore.kernel.org/all/20250729193647.3410634-1-marievic@google.com/ - Establish parameterized testing terminology: - "parameterized test" will refer to the group of all runs of a single test function with different parameters. - "parameter run" will refer to the execution of the test case function with a single parameter. - "parameterized test context" is the `struct kunit` that holds the context for the entire parameterized test. - "parameter run context" is the `struct kunit` that holds the context of the individual parameter run. - A test is defined to be a parameterized tests if it was registered with a generator function. - Make comment edits to reflect the established terminology. - Require users to manually pass kunit_array_gen_params() to KUNIT_CASE_PARAM_WITH_INIT() as the generator function, unless they want to provide their own generator function, if the parameter array was registered in param_init(). This is to be consistent with the definition of a parameterized test, i.e. generate_params() is never NULL if it's a parameterized test. - Change name of kunit_get_next_param_and_desc() to kunit_array_gen_params(). - Other minor function name changes such as removing the "__" prefix in front of internal functions. - Change signature of get_description() in `struct params_array` to accept the parameterized test context, as well. - Output the KTAP test plan for a parameterized test when the parameter count is available. - Cover letter was made more concise. - Edits to the example tests. - Fix bug of parameterized test init/exit logic being done outside of the parameterized test check. - Fix bugs identified by the kernel test robot. --- Marie Zhussupova (7): kunit: Add parent kunit for parameterized test context kunit: Introduce param_init/exit for parameterized test context management kunit: Pass parameterized test context to generate_params() kunit: Enable direct registration of parameter arrays to a KUnit test kunit: Add example parameterized test with shared resource management using the Resource API kunit: Add example parameterized test with direct dynamic parameter array setup Documentation: kunit: Document new parameterized test features Documentation/dev-tools/kunit/usage.rst | 342 +++++++++++++++++++++++- drivers/gpu/drm/xe/tests/xe_pci.c | 2 +- include/kunit/test.h | 95 ++++++- kernel/kcsan/kcsan_test.c | 2 +- lib/kunit/kunit-example-test.c | 217 +++++++++++++++ lib/kunit/test.c | 94 +++++-- rust/kernel/kunit.rs | 4 + 7 files changed, 728 insertions(+), 28 deletions(-) -- 2.51.0.rc1.167.g924127e9c0-goog

2 weeks, 6 days

3
9
0 0

[PATCH v2 00/19] rust: replace `kernel::c_str!` with C-Strings

by Tamir Duberstein

This series depends on step 3[0] which depends on steps 2a[1] and 2b[2] which both depend on step 1[3]. This series also has a minor merge conflict with a small change[4] that was taken through driver-core-testing. This series is marked as depending on that change; as such it contains the post-conflict patch. Subsystem maintainers: I would appreciate your `Acked-by`s so that this can be taken through Miguel's tree (where the previous series must go). Link https://lore.kernel.org/all/20250710-cstr-core-v14-0-ca7e0ca82c82@gmail.com/ [0] Link: https://lore.kernel.org/all/20250709-core-cstr-fanout-1-v1-0-64308e7203fc@g… [1] Link: https://lore.kernel.org/all/20250709-core-cstr-fanout-1-v1-0-fd793b3e58a2@g… [2] Link: https://lore.kernel.org/all/20250704-core-cstr-prepare-v1-0-a91524037783@gm… [3] Link: https://lore.kernel.org/all/20250704-cstr-include-aux-v1-1-e1a404ae92ac@gma… [4] Signed-off-by: Tamir Duberstein <tamird(a)gmail.com> --- Changes in v2: - Rebase. - Add two patches to address new code. - Drop incorrectly applied Acked-by tags from Danilo. - Link to v1: https://lore.kernel.org/r/20250710-core-cstr-cstrings-v1-0-027420ea799e@gma… --- Tamir Duberstein (19): drivers: net: replace `kernel::c_str!` with C-Strings gpu: nova-core: replace `kernel::c_str!` with C-Strings rust: auxiliary: replace `kernel::c_str!` with C-Strings rust: clk: replace `kernel::c_str!` with C-Strings rust: configfs: replace `kernel::c_str!` with C-Strings rust: cpufreq: replace `kernel::c_str!` with C-Strings rust: device: replace `kernel::c_str!` with C-Strings rust: firmware: replace `kernel::c_str!` with C-Strings rust: kunit: replace `kernel::c_str!` with C-Strings rust: macros: replace `kernel::c_str!` with C-Strings rust: miscdevice: replace `kernel::c_str!` with C-Strings rust: net: replace `kernel::c_str!` with C-Strings rust: pci: replace `kernel::c_str!` with C-Strings rust: platform: replace `kernel::c_str!` with C-Strings rust: seq_file: replace `kernel::c_str!` with C-Strings rust: str: replace `kernel::c_str!` with C-Strings rust: sync: replace `kernel::c_str!` with C-Strings rust: io: replace `kernel::c_str!` with C-Strings rust: regulator: replace `kernel::c_str!` with C-Strings drivers/block/rnull.rs | 2 +- drivers/cpufreq/rcpufreq_dt.rs | 5 ++--- drivers/gpu/drm/nova/driver.rs | 10 +++++----- drivers/gpu/nova-core/driver.rs | 6 +++--- drivers/net/phy/ax88796b_rust.rs | 7 +++---- drivers/net/phy/qt2025.rs | 5 ++--- rust/kernel/clk.rs | 6 ++---- rust/kernel/configfs.rs | 9 +++++---- rust/kernel/cpufreq.rs | 3 +-- rust/kernel/device.rs | 4 +--- rust/kernel/device/property.rs | 6 +++--- rust/kernel/firmware.rs | 6 +++--- rust/kernel/io/mem.rs | 7 +++---- rust/kernel/kunit.rs | 11 ++++------- rust/kernel/net/phy.rs | 6 ++---- rust/kernel/platform.rs | 6 +++--- rust/kernel/regulator.rs | 9 +++------ rust/kernel/seq_file.rs | 4 ++-- rust/kernel/str.rs | 5 ++--- rust/kernel/sync.rs | 5 ++--- rust/kernel/sync/completion.rs | 2 +- rust/kernel/workqueue.rs | 8 ++++---- rust/macros/kunit.rs | 10 +++++----- rust/macros/module.rs | 2 +- samples/rust/rust_configfs.rs | 5 ++--- samples/rust/rust_driver_auxiliary.rs | 4 ++-- samples/rust/rust_driver_faux.rs | 4 ++-- samples/rust/rust_driver_pci.rs | 4 ++-- samples/rust/rust_driver_platform.rs | 30 ++++++++++++++---------------- samples/rust/rust_misc_device.rs | 3 +-- scripts/rustdoc_test_gen.rs | 4 ++-- 31 files changed, 88 insertions(+), 110 deletions(-) --- base-commit: 8f5ae30d69d7543eee0d70083daf4de8fe15d585 change-id: 20250710-core-cstr-cstrings-1faaa632f0fd prerequisite-message-id: 20250813-core-cstr-fanout-1-v3-0-545c14bc44ff(a)gmail.com prerequisite-patch-id: 0ccc3545ff9bf22a67b79a944705cef2fb9c2bbf prerequisite-patch-id: b1866166714606d5c11a4d7506abe4c2f86dac8d prerequisite-patch-id: b575ae9ef33020b691c8c5a17bd1985676519e14 prerequisite-patch-id: 8fee5e2daf0749362331dad4fc63d907a01b14e9 prerequisite-patch-id: 366ef1f93fb40b1d039768f2041ff79995e7e228 prerequisite-patch-id: 1d350291f9292f910081856d8f7d5e4d9545cfd1 prerequisite-patch-id: 9a6a60bd2b209126de64c16a77a3a1d229dd898c prerequisite-patch-id: 08ae5855768ec3b4c68272b86d2a0e0667c9aa47 prerequisite-patch-id: 801be981c2346617fa9412498930b68dc784693b prerequisite-patch-id: f0dbf0a55a27fe8e199e242d1f79ea800d1ddb66 prerequisite-patch-id: c0b4abb4d44f7e63d002d0bfe5239296930c183e prerequisite-message-id: 20250813-core-cstr-fanout-1-v3-0-a15eca059c51(a)gmail.com prerequisite-patch-id: 6711f2a2f25c12784057aa725a9482feef6bb6f0 prerequisite-patch-id: 3b5144133c0e239e0a258c9aa4da0df2dd464e66 prerequisite-patch-id: 589a352ba7f7c9aefefd84dfd3b6b20e290b0d14 prerequisite-patch-id: 2a4b0b9170e25637b9eba0e516863bdcdb4149a8 prerequisite-patch-id: 3d89601bba1fb01d190b0ba415b28ad9cbf1e209 prerequisite-patch-id: 10923aebf24011b727f60496c0f9e0ad57e0a967 prerequisite-patch-id: 9a7e8ba460358985147efd347658be31fbc78ba2 prerequisite-patch-id: f79b8755f3d75effc581d09eafe5725043516aad prerequisite-patch-id: d598958c2d64dcb56a5cd64b088594be51b1d752 prerequisite-change-id: 20250201-cstr-core-d4b9b69120cf:v15 prerequisite-patch-id: 6711f2a2f25c12784057aa725a9482feef6bb6f0 prerequisite-patch-id: 3b5144133c0e239e0a258c9aa4da0df2dd464e66 prerequisite-patch-id: 0ccc3545ff9bf22a67b79a944705cef2fb9c2bbf prerequisite-patch-id: b1866166714606d5c11a4d7506abe4c2f86dac8d prerequisite-patch-id: 589a352ba7f7c9aefefd84dfd3b6b20e290b0d14 prerequisite-patch-id: 2a4b0b9170e25637b9eba0e516863bdcdb4149a8 prerequisite-patch-id: 3d89601bba1fb01d190b0ba415b28ad9cbf1e209 prerequisite-patch-id: 10923aebf24011b727f60496c0f9e0ad57e0a967 prerequisite-patch-id: 9a7e8ba460358985147efd347658be31fbc78ba2 prerequisite-patch-id: f79b8755f3d75effc581d09eafe5725043516aad prerequisite-patch-id: d598958c2d64dcb56a5cd64b088594be51b1d752 prerequisite-patch-id: b575ae9ef33020b691c8c5a17bd1985676519e14 prerequisite-patch-id: 8fee5e2daf0749362331dad4fc63d907a01b14e9 prerequisite-patch-id: 366ef1f93fb40b1d039768f2041ff79995e7e228 prerequisite-patch-id: 1d350291f9292f910081856d8f7d5e4d9545cfd1 prerequisite-patch-id: 9a6a60bd2b209126de64c16a77a3a1d229dd898c prerequisite-patch-id: 08ae5855768ec3b4c68272b86d2a0e0667c9aa47 prerequisite-patch-id: 801be981c2346617fa9412498930b68dc784693b prerequisite-patch-id: f0dbf0a55a27fe8e199e242d1f79ea800d1ddb66 prerequisite-patch-id: c0b4abb4d44f7e63d002d0bfe5239296930c183e prerequisite-patch-id: 9c0a6624ed7b7e1d0373985c5c084a844e7c49ce prerequisite-patch-id: e0ca756f740ab0ce7478bbf6510948ba89529a2f prerequisite-patch-id: 6d8dbdf864f79fc0c2820e702a7cb87753649ca0 prerequisite-patch-id: 7d4d1d036043a85dcbaf0d09ea85768120efe094 Best regards, -- Tamir Duberstein <tamird(a)gmail.com>

2 weeks, 6 days

6
21
0 0

[PATCH] selftests/kselftest_harness: Add harness-selftest.expected to TEST_FILES

by Yi Lai

The harness-selftest.expected is not installed in INSTALL_PATH. Attempting to execute harness-selftest.sh shows warning: diff: ./kselftest_harness/harness-selftest.expected: No such file or directory Add harness-selftest.expected to TEST_FILES. Signed-off-by: Yi Lai <yi1.lai(a)intel.com> --- tools/testing/selftests/kselftest_harness/Makefile | 1 + 1 file changed, 1 insertion(+) diff --git a/tools/testing/selftests/kselftest_harness/Makefile b/tools/testing/selftests/kselftest_harness/Makefile index 0617535a6ce4..d2369c01701a 100644 --- a/tools/testing/selftests/kselftest_harness/Makefile +++ b/tools/testing/selftests/kselftest_harness/Makefile @@ -2,6 +2,7 @@ TEST_GEN_PROGS_EXTENDED := harness-selftest TEST_PROGS := harness-selftest.sh +TEST_FILES := harness-selftest.expected EXTRA_CLEAN := harness-selftest.seen include ../lib.mk -- 2.43.0

2 weeks, 6 days

3
2
0 0

[PATCH net-next v2] selftests: drv-net: wait for carrier

by Jakub Kicinski

On fast machines the tests run in quick succession so even when tests clean up after themselves the carrier may need some time to come back. Specifically in NIPA when ping.py runs right after netpoll_basic.py the first ping command fails. Since the context manager callbacks are now common NetDrvEpEnv gets an ip link up call as well. Signed-off-by: Jakub Kicinski <kuba(a)kernel.org> --- v2: - add an empty __del__ v1: https://lore.kernel.org/20250808225741.1095702-1-kuba@kernel.org CC: shuah(a)kernel.org CC: willemb(a)google.com CC: petrm(a)nvidia.com CC: linux-kselftest(a)vger.kernel.org --- .../selftests/drivers/net/lib/py/__init__.py | 2 +- .../selftests/drivers/net/lib/py/env.py | 41 +++++++++---------- tools/testing/selftests/net/lib/py/utils.py | 18 ++++++++ 3 files changed, 39 insertions(+), 22 deletions(-) diff --git a/tools/testing/selftests/drivers/net/lib/py/__init__.py b/tools/testing/selftests/drivers/net/lib/py/__init__.py index 8711c67ad658..a07b56a75c8a 100644 --- a/tools/testing/selftests/drivers/net/lib/py/__init__.py +++ b/tools/testing/selftests/drivers/net/lib/py/__init__.py @@ -15,7 +15,7 @@ KSFT_DIR = (Path(__file__).parent / "../../../..").resolve() NlError, RtnlFamily, DevlinkFamily from net.lib.py import CmdExitFailure from net.lib.py import bkg, cmd, bpftool, bpftrace, defer, ethtool, \ - fd_read_timeout, ip, rand_port, tool, wait_port_listen + fd_read_timeout, ip, rand_port, tool, wait_port_listen, wait_file from net.lib.py import fd_read_timeout from net.lib.py import KsftSkipEx, KsftFailEx, KsftXfailEx from net.lib.py import ksft_disruptive, ksft_exit, ksft_pr, ksft_run, \ diff --git a/tools/testing/selftests/drivers/net/lib/py/env.py b/tools/testing/selftests/drivers/net/lib/py/env.py index 1b8bd648048f..c1f3b608c6d8 100644 --- a/tools/testing/selftests/drivers/net/lib/py/env.py +++ b/tools/testing/selftests/drivers/net/lib/py/env.py @@ -4,7 +4,7 @@ import os import time from pathlib import Path from lib.py import KsftSkipEx, KsftXfailEx -from lib.py import ksft_setup +from lib.py import ksft_setup, wait_file from lib.py import cmd, ethtool, ip, CmdExitFailure from lib.py import NetNS, NetdevSimDev from .remote import Remote @@ -25,6 +25,9 @@ from .remote import Remote self.env = self._load_env_file() + # Following attrs must be set be inheriting classes + self.dev = None + def _load_env_file(self): env = os.environ.copy() @@ -48,6 +51,22 @@ from .remote import Remote env[pair[0]] = pair[1] return ksft_setup(env) + def __del__(self): + pass + + def __enter__(self): + ip(f"link set dev {self.dev['ifname']} up") + wait_file(f"/sys/class/net/{self.dev['ifname']}/carrier", + lambda x: x.strip() == "1") + + return self + + def __exit__(self, ex_type, ex_value, ex_tb): + """ + __exit__ gets called at the end of a "with" block. + """ + self.__del__() + class NetDrvEnv(NetDrvEnvBase): """ @@ -72,17 +91,6 @@ from .remote import Remote self.ifname = self.dev['ifname'] self.ifindex = self.dev['ifindex'] - def __enter__(self): - ip(f"link set dev {self.dev['ifname']} up") - - return self - - def __exit__(self, ex_type, ex_value, ex_tb): - """ - __exit__ gets called at the end of a "with" block. - """ - self.__del__() - def __del__(self): if self._ns: self._ns.remove() @@ -219,15 +227,6 @@ from .remote import Remote raise Exception("Can't resolve remote interface name, multiple interfaces match") return v6[0]["ifname"] if v6 else v4[0]["ifname"] - def __enter__(self): - return self - - def __exit__(self, ex_type, ex_value, ex_tb): - """ - __exit__ gets called at the end of a "with" block. - """ - self.__del__() - def __del__(self): if self._ns: self._ns.remove() diff --git a/tools/testing/selftests/net/lib/py/utils.py b/tools/testing/selftests/net/lib/py/utils.py index f395c90fb0f1..c42bffea0d87 100644 --- a/tools/testing/selftests/net/lib/py/utils.py +++ b/tools/testing/selftests/net/lib/py/utils.py @@ -249,3 +249,21 @@ global_defer_queue = [] if time.monotonic() > end: raise Exception("Waiting for port listen timed out") time.sleep(sleep) + + +def wait_file(fname, test_fn, sleep=0.005, deadline=5, encoding='utf-8'): + """ + Wait for file contents on the local system to satisfy a condition. + test_fn() should take one argument (file contents) and return whether + condition is met. + """ + end = time.monotonic() + deadline + + with open(fname, "r", encoding=encoding) as fp: + while True: + if test_fn(fp.read()): + break + fp.seek(0) + if time.monotonic() > end: + raise TimeoutError("Wait for file contents failed", fname) + time.sleep(sleep) -- 2.50.1

2 weeks, 6 days

3
2
0 0

[PATCH v3 0/4] Better split_huge_page_test result check

by Zi Yan

This patchset uses kpageflags to get after-split folio orders for a better split_huge_page_test result check[1]. The added gather_folio_orders() scans through a VPN range and collects the numbers of folios at different orders. check_folio_orders() compares the result of gather_folio_orders() to a given list of numbers of different orders. This patchset also added new order and in folio offset to the split huge page debugfs's pr_debug()s; Changelog === From V2[3]: 1. Added two missing free()s in check_folio_orders(). 2. Reimplemented is_backed_by_thp() to use kpageflags to get precise folio order information and renamed it to is_backed_by_folio() in new Patch 3. 3. Renamed *_file to *_fd in Patch 2. 4. Indentation fixes. 5. Fixed vaddr stepping issue in gather_folio_orders() when a compound tail page is encountered. 6. Used pmd_order in place of max_order in split_huge_page_test.c. 7. Documented gather_folio_orders(). From V1[2]: 1. Dropped split_huge_pages_pid() for loop step change to avoid messing up with PTE-mapped THP handling. split_huge_page_test.c is changed to perform split at [addr, addr + pagesize) range to limit one folio_split() per folio. 2. Moved pr_debug changes in Patch 2 to Patch 1. 3. Moved KPF_* to vm_util.h and used PAGEMAP_PFN instead of local PFN_MASK. 4. Used pagemap_get_pfn() helper. 5. Used char *vaddr and size_t len as inputs to gather_folio_orders() and check_folio_orders() instead of vpn and nr_pages. 6. Removed variable length variables and used malloc instead. [1] https://lore.kernel.org/linux-mm/e2f32bdb-e4a4-447c-867c-31405cbba151@redha… [2] https://lore.kernel.org/linux-mm/20250806022045.342824-1-ziy@nvidia.com/ [3] https://lore.kernel.org/linux-mm/20250808190144.797076-1-ziy@nvidia.com/ Zi Yan (4): mm/huge_memory: add new_order and offset to split_huge_pages*() pr_debug. selftests/mm: add check_folio_orders() helper. selftests/mm: reimplement is_backed_by_thp() with more precise check selftests/mm: check after-split folio orders in split_huge_page_test. mm/huge_memory.c | 8 +- .../selftests/mm/split_huge_page_test.c | 154 +++++++++++----- tools/testing/selftests/mm/vm_util.c | 173 ++++++++++++++++++ tools/testing/selftests/mm/vm_util.h | 8 + 4 files changed, 292 insertions(+), 51 deletions(-) -- 2.47.2

3 weeks

3
12
0 0

[PATCH] print: fix spelling error in message

by Madhur Kumar

Signed-off-by: Madhur Kumar <madhurkumar004(a)gmail.com> --- tools/testing/selftests/net/openvswitch/ovs-dpctl.py | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/net/openvswitch/ovs-dpctl.py b/tools/testing/selftests/net/openvswitch/ovs-dpctl.py index 8a0396bfa..b521e0dea 100644 --- a/tools/testing/selftests/net/openvswitch/ovs-dpctl.py +++ b/tools/testing/selftests/net/openvswitch/ovs-dpctl.py @@ -1877,7 +1877,7 @@ class OvsPacket(GenericNetlinkSocket): elif msg["cmd"] == OvsPacket.OVS_PACKET_CMD_EXECUTE: up.execute(msg) else: - print("Unkonwn cmd: %d" % msg["cmd"]) + print("Unknown cmd: %d" % msg["cmd"]) except NetlinkError as ne: raise ne -- 2.50.1

3 weeks

2
1
0 0

[PATCH bpf-next v8 0/2] libbpf: fix USDT SIB argument handling causing unrecognized register error

by Jiawei Zhao

When using GCC on x86-64 to compile an usdt prog with -O1 or higher optimization, the compiler will generate SIB addressing mode for global array and PC-relative addressing mode for global variable, e.g. "1@-96(%rbp,%rax,8)" and "-1@4+t1(%rip)". The current USDT implementation in libbpf cannot parse these two formats, causing `bpf_program__attach_usdt()` to fail with -ENOENT (unrecognized register). This patch series adds support for SIB addressing mode in USDT probes. The main changes include: - add correct handling logic for SIB-addressed arguments in `parse_usdt_arg`. - add an usdt_o2 test case to cover SIB addressing mode. Testing shows that the SIB probe correctly generates 8@(%rcx,%rax,8) argument spec and passes all validation checks. The modification history of this patch series: Change since v1: - refactor the code to make it more readable - modify the commit message to explain why and how Change since v2: - fix the `scale` uninitialized error Change since v3: - force -O2 optimization for usdt.test.o to generate SIB addressing usdt and pass all test cases. Change since v4: - split the patch into two parts, one for the fix and the other for the test Change since v5: - Only enable optimization for x86 architecture to generate SIB addressing usdt argument spec. Change since v6: - Add an usdt_o2 test case to cover SIB addressing mode. - Reinstate the usdt.c test case. Change since v7: - Refactor modifications to __bpf_usdt_arg_spec to avoid increasing its size, achieving better compatibility - Fix some minor code style issues - Refactor the usdt_o2 test case, removing semaphore and adding GCC attribute to force -O2 optimization Jiawei Zhao (2): libbpf: fix USDT SIB argument handling causing unrecognized register error selftests/bpf: Add an usdt_o2 test case in selftests to cover SIB handling logic tools/lib/bpf/usdt.bpf.h | 55 ++++++++++++++- tools/lib/bpf/usdt.c | 61 ++++++++++++++-- tools/testing/selftests/bpf/Makefile | 1 + .../selftests/bpf/prog_tests/usdt_o2.c | 69 +++++++++++++++++++ .../selftests/bpf/progs/test_usdt_o2.c | 37 ++++++++++ 5 files changed, 216 insertions(+), 7 deletions(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/usdt_o2.c create mode 100644 tools/testing/selftests/bpf/progs/test_usdt_o2.c -- 2.43.0

3 weeks

3
5
0 0

[PATCH bpf-next v9 0/3] libbpf: fix USDT SIB argument handling causing unrecognized register error

by Jiawei Zhao

When using GCC on x86-64 to compile an usdt prog with -O1 or higher optimization, the compiler will generate SIB addressing mode for global array and PC-relative addressing mode for global variable, e.g. "1@-96(%rbp,%rax,8)" and "-1@4+t1(%rip)". The current USDT implementation in libbpf cannot parse these two formats, causing `bpf_program__attach_usdt()` to fail with -ENOENT (unrecognized register). This patch series adds support for SIB addressing mode in USDT probes. The main changes include: - add correct handling logic for SIB-addressed arguments in `parse_usdt_arg`. - add an usdt_o2 test case to cover SIB addressing mode. Testing shows that the SIB probe correctly generates 8@(%rcx,%rax,8) argument spec and passes all validation checks. The modification history of this patch series: Change since v1: - refactor the code to make it more readable - modify the commit message to explain why and how Change since v2: - fix the `scale` uninitialized error Change since v3: - force -O2 optimization for usdt.test.o to generate SIB addressing usdt and pass all test cases. Change since v4: - split the patch into two parts, one for the fix and the other for the test Change since v5: - Only enable optimization for x86 architecture to generate SIB addressing usdt argument spec. Change since v6: - Add an usdt_o2 test case to cover SIB addressing mode. - Reinstate the usdt.c test case. Change since v7: - Refactor modifications to __bpf_usdt_arg_spec to avoid increasing its size, achieving better compatibility - Fix some minor code style issues - Refactor the usdt_o2 test case, removing semaphore and adding GCC attribute to force -O2 optimization Change since v8: - Refactor the usdt_o2 test case, using assembly to force SIB addressing mode. Jiawei Zhao (3): libbpf: fix USDT SIB argument handling causing unrecognized register error selftests/bpf: Add an usdt_o2 test case in selftests to cover SIB handling logic selftests/bpf: make usdt_o2 reliably generate SIB USDT arg spec tools/lib/bpf/usdt.bpf.h | 54 +++++++++++++- tools/lib/bpf/usdt.c | 61 ++++++++++++++-- tools/testing/selftests/bpf/Makefile | 1 + .../selftests/bpf/prog_tests/usdt_o2.c | 73 +++++++++++++++++++ .../selftests/bpf/progs/test_usdt_o2.c | 37 ++++++++++ 5 files changed, 219 insertions(+), 7 deletions(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/usdt_o2.c create mode 100644 tools/testing/selftests/bpf/progs/test_usdt_o2.c -- 2.43.0

3 weeks

1
3
0 0

[PATCH bpf-next v9 0/3] libbpf: fix USDT SIB argument handling causing unrecognized register error

by Jiawei Zhao

When using GCC on x86-64 to compile an usdt prog with -O1 or higher optimization, the compiler will generate SIB addressing mode for global array and PC-relative addressing mode for global variable, e.g. "1@-96(%rbp,%rax,8)" and "-1@4+t1(%rip)". The current USDT implementation in libbpf cannot parse these two formats, causing `bpf_program__attach_usdt()` to fail with -ENOENT (unrecognized register). This patch series adds support for SIB addressing mode in USDT probes. The main changes include: - add correct handling logic for SIB-addressed arguments in `parse_usdt_arg`. - add an usdt_o2 test case to cover SIB addressing mode. Testing shows that the SIB probe correctly generates 8@(%rcx,%rax,8) argument spec and passes all validation checks. The modification history of this patch series: Change since v1: - refactor the code to make it more readable - modify the commit message to explain why and how Change since v2: - fix the `scale` uninitialized error Change since v3: - force -O2 optimization for usdt.test.o to generate SIB addressing usdt and pass all test cases. Change since v4: - split the patch into two parts, one for the fix and the other for the test Change since v5: - Only enable optimization for x86 architecture to generate SIB addressing usdt argument spec. Change since v6: - Add an usdt_o2 test case to cover SIB addressing mode. - Reinstate the usdt.c test case. Change since v7: - Refactor modifications to __bpf_usdt_arg_spec to avoid increasing its size, achieving better compatibility - Fix some minor code style issues - Refactor the usdt_o2 test case, removing semaphore and adding GCC attribute to force -O2 optimization Change since v8: - Refactor the usdt_o2 test case, using assembly to force SIB addressing mode. Jiawei Zhao (3): libbpf: fix USDT SIB argument handling causing unrecognized register error selftests/bpf: Add an usdt_o2 test case in selftests to cover SIB handling logic selftests/bpf: make usdt_o2 reliably generate SIB USDT arg spec tools/lib/bpf/usdt.bpf.h | 54 +- tools/lib/bpf/usdt.c | 61 +- tools/testing/selftests/bpf/Makefile | 1 + .../selftests/bpf/prog_tests/usdt_o2.c | 73 + .../selftests/bpf/progs/test_usdt_o2.c | 37 + tools/testing/selftests/bpf/record.log | 22207 ++++++++++++++++ 6 files changed, 22426 insertions(+), 7 deletions(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/usdt_o2.c create mode 100644 tools/testing/selftests/bpf/progs/test_usdt_o2.c create mode 100644 tools/testing/selftests/bpf/record.log -- 2.43.0

3 weeks

1
3
0 0

[RFC PATCH] kunit: Put checking for existing named resource between locks to prevent race conditions in the Resource API

by Marie Zhussupova

Named resources attached to a KUnit test must be unique. Currently, the check for existing named resources in kunit_add_named_resource() is performed without a lock. While KUnit is largely single-threaded, a race condition could theoretically lead to multiple resources with the same name being added. To prevent this, the uniqueness check logic has been moved into the locked portion of the __kunit_add_resource() function. This ensures that the check and resource addition are atomic, preventing duplicate named resources. Signed-off-by: Marie Zhussupova <marievic(a)google.com> --- This patch raises a fundamental question about KUnit's concurrency model. What are the thread-safety guarantees that KUnit should provide? Should these guarantees be formally defined before we introduce changes like this one? It would be great to have everyone's thoughts on this, as it could have implications on how we have handle concurrency in KUnit going forward. --- include/kunit/resource.h | 84 ++++++++++++++++++++++++++++++---------- lib/kunit/resource.c | 12 +++++- 2 files changed, 74 insertions(+), 22 deletions(-) diff --git a/include/kunit/resource.h b/include/kunit/resource.h index 4ad69a2642a5..7b33f332769c 100644 --- a/include/kunit/resource.h +++ b/include/kunit/resource.h @@ -148,12 +148,14 @@ static inline void kunit_put_resource(struct kunit_resource *res) * If an init function is supplied, @data is passed to it instead. * @free: a user-supplied function to free the resource (if needed). * @res: The resource. + * @name: name of the resource if there is one. * @data: value to pass to init function or set in resource data field. */ int __kunit_add_resource(struct kunit *test, kunit_resource_init_t init, kunit_resource_free_t free, struct kunit_resource *res, + const char *name, void *data); /** @@ -173,7 +175,7 @@ static inline int kunit_add_resource(struct kunit *test, void *data) { res->should_kfree = false; - return __kunit_add_resource(test, init, free, res, data); + return __kunit_add_resource(test, init, free, res, NULL, data); } static inline struct kunit_resource * @@ -195,21 +197,14 @@ static inline int kunit_add_named_resource(struct kunit *test, const char *name, void *data) { - struct kunit_resource *existing; if (!name) return -EINVAL; - existing = kunit_find_named_resource(test, name); - if (existing) { - kunit_put_resource(existing); - return -EEXIST; - } - res->name = name; res->should_kfree = false; - return __kunit_add_resource(test, init, free, res, data); + return __kunit_add_resource(test, init, free, res, name, data); } /** @@ -249,7 +244,7 @@ kunit_alloc_and_get_resource(struct kunit *test, res->should_kfree = true; - ret = __kunit_add_resource(test, init, free, res, context); + ret = __kunit_add_resource(test, init, free, res, NULL, context); if (!ret) { /* * bump refcount for get; kunit_resource_put() should be called @@ -290,7 +285,7 @@ static inline void *kunit_alloc_resource(struct kunit *test, return NULL; res->should_kfree = true; - if (!__kunit_add_resource(test, init, free, res, context)) + if (!__kunit_add_resource(test, init, free, res, NULL, context)) return res->data; return NULL; @@ -314,29 +309,54 @@ static inline bool kunit_resource_name_match(struct kunit *test, } /** - * kunit_find_resource() - Find a resource using match function/data. + * kunit_find_resource_unlocked() - Find a resource using match function/data + * without locking. * @test: Test case to which the resource belongs. - * @match: match function to be applied to resources/match data. - * @match_data: data to be used in matching. + * @match: Match function to be applied to resources/match data. + * @match_data: Data to be used in matching. + * + * Finds a resource in @test->resources using @match, but does not acquire + * the test's lock. + * + * Note: This function is for specialized use only as it is **NOT thread-safe** + * regarding the test's resource list and test reference count. Callers must prevent + * potential race conditions, typically by providing external locking. The thread-safe + * alternative, kunit_find_resource(), should be used in most situations. */ static inline struct kunit_resource * -kunit_find_resource(struct kunit *test, - kunit_resource_match_t match, - void *match_data) +kunit_find_resource_unlocked(struct kunit *test, + kunit_resource_match_t match, + void *match_data) { struct kunit_resource *res, *found = NULL; - unsigned long flags; - - spin_lock_irqsave(&test->lock, flags); list_for_each_entry_reverse(res, &test->resources, node) { - if (match(test, res, (void *)match_data)) { + if (match(test, res, match_data)) { found = res; kunit_get_resource(found); break; } } + return found; +} + +/** + * kunit_find_resource() - Find a resource using match function/data. + * @test: Test case to which the resource belongs. + * @match: match function to be applied to resources/match data. + * @match_data: data to be used in matching. + */ +static inline struct kunit_resource * +kunit_find_resource(struct kunit *test, + kunit_resource_match_t match, + void *match_data) +{ + struct kunit_resource *found = NULL; + unsigned long flags; + + spin_lock_irqsave(&test->lock, flags); + found = kunit_find_resource_unlocked(test, match, match_data); spin_unlock_irqrestore(&test->lock, flags); return found; @@ -355,6 +375,28 @@ kunit_find_named_resource(struct kunit *test, (void *)name); } +/** + * kunit_find_named_resource_unlocked() - Find a resource using match name + * without locking. + * @test: Test case to which the resource belongs. + * @name: Match name. + * + * Finds a resource in @test->resources using its name, but does not acquire + * the test's resource lock. + * + * Note: This function is for specialized use only as it is **NOT thread-safe** + * regarding the test's resource list and test reference count. Callers must prevent + * potential race conditions, typically by providing external locking. The thread-safe + * alternative, kunit_find_named_resource(), should be used in most situations. + */ +static inline struct kunit_resource * +kunit_find_named_resource_unlocked(struct kunit *test, + const char *name) +{ + return kunit_find_resource_unlocked(test, kunit_resource_name_match, + (void *)name); +} + /** * kunit_destroy_resource() - Find a kunit_resource and destroy it. * @test: Test case to which the resource belongs. diff --git a/lib/kunit/resource.c b/lib/kunit/resource.c index f0209252b179..dae708f81f97 100644 --- a/lib/kunit/resource.c +++ b/lib/kunit/resource.c @@ -20,10 +20,12 @@ int __kunit_add_resource(struct kunit *test, kunit_resource_init_t init, kunit_resource_free_t free, struct kunit_resource *res, + const char *name, void *data) { int ret = 0; unsigned long flags; + struct kunit_resource *existing; res->free = free; kref_init(&res->refcount); @@ -37,6 +39,14 @@ int __kunit_add_resource(struct kunit *test, } spin_lock_irqsave(&test->lock, flags); + if (name) { + existing = kunit_find_named_resource_unlocked(test, name); + if (existing) { + kunit_put_resource(existing); + spin_unlock_irqrestore(&test->lock, flags); + return -EEXIST; + } + } list_add_tail(&res->node, &test->resources); /* refcount for list is established by kref_init() */ spin_unlock_irqrestore(&test->lock, flags); @@ -107,7 +117,7 @@ int kunit_add_action(struct kunit *test, void (*action)(void *), void *ctx) action_ctx->res.should_kfree = true; /* As init is NULL, this cannot fail. */ - __kunit_add_resource(test, NULL, __kunit_action_free, &action_ctx->res, action_ctx); + __kunit_add_resource(test, NULL, __kunit_action_free, &action_ctx->res, NULL, action_ctx); return 0; } -- 2.51.0.rc0.215.g125493bb4a-goog

3 weeks

1
0
0 0

2025

2024

2023

2022

2021

2020

2019

2018

2017

Linux-kselftest-mirror August 2025