From aeb709c767aeca996e6011133e4f7bdb2a4af652 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Wed, 30 Sep 2026 09:59:20 +0000 Subject: selftests/bpf: Add a test for objects stuck in free_by_rcu_ttrace Delete all elements of BPF_F_NO_PREALLOC hash map in one batch. The first free_bulk() starts RCU tasks trace GP and the rest of the elements are freed while it's in flight. Wait for call_rcu_ttrace_in_progress to clear in bpf_mem_cache of every cpu and check that free_by_rcu_ttrace and waiting_for_gp_ttrace lists are empty. Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20260930095920.601738-4-alexei.starovoitov@gmail.com Signed-off-by: Kumar Kartikeya Dwivedi --- lib/test_memcat_p.c | 116 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 116 insertions(+) create mode 100644 lib/test_memcat_p.c (limited to 'lib/test_memcat_p.c') diff --git a/lib/test_memcat_p.c b/lib/test_memcat_p.c new file mode 100644 index 000000000..62f1633b3 --- /dev/null +++ b/lib/test_memcat_p.c @@ -0,0 +1,116 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Test cases for memcat_p() in lib/memcat_p.c + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include + +struct test_struct { + int num; + unsigned int magic; +}; + +#define MAGIC 0xf00ff00f +/* Size of each of the NULL-terminated input arrays */ +#define INPUT_MAX 128 +/* Expected number of non-NULL elements in the output array */ +#define EXPECT (INPUT_MAX * 2 - 2) + +static int __init test_memcat_p_init(void) +{ + struct test_struct **in0, **in1, **out, **p; + int err = -ENOMEM, i, r, total = 0; + + in0 = kzalloc_objs(*in0, INPUT_MAX); + if (!in0) + return err; + + in1 = kzalloc_objs(*in1, INPUT_MAX); + if (!in1) + goto err_free_in0; + + for (i = 0, r = 1; i < INPUT_MAX - 1; i++) { + in0[i] = kmalloc_obj(**in0); + if (!in0[i]) + goto err_free_elements; + + in1[i] = kmalloc_obj(**in1); + if (!in1[i]) { + kfree(in0[i]); + goto err_free_elements; + } + + /* lifted from test_sort.c */ + r = (r * 725861) % 6599; + in0[i]->num = r; + in1[i]->num = -r; + in0[i]->magic = MAGIC; + in1[i]->magic = MAGIC; + } + + in0[i] = in1[i] = NULL; + + out = memcat_p(in0, in1); + if (!out) + goto err_free_all_elements; + + err = -EINVAL; + for (i = 0, p = out; *p && (i < INPUT_MAX * 2 - 1); p++, i++) { + total += (*p)->num; + + if ((*p)->magic != MAGIC) { + pr_err("test failed: wrong magic at %d: %u\n", i, + (*p)->magic); + goto err_free_out; + } + } + + if (total) { + pr_err("test failed: expected zero total, got %d\n", total); + goto err_free_out; + } + + if (i != EXPECT) { + pr_err("test failed: expected output size %d, got %d\n", + EXPECT, i); + goto err_free_out; + } + + for (i = 0; i < INPUT_MAX - 1; i++) + if (out[i] != in0[i] || out[i + INPUT_MAX - 1] != in1[i]) { + pr_err("test failed: wrong element order at %d\n", i); + goto err_free_out; + } + + err = 0; + pr_info("test passed\n"); + +err_free_out: + kfree(out); +err_free_all_elements: + i = INPUT_MAX; +err_free_elements: + for (i--; i >= 0; i--) { + kfree(in1[i]); + kfree(in0[i]); + } + + kfree(in1); +err_free_in0: + kfree(in0); + + return err; +} + +static void __exit test_memcat_p_exit(void) +{ +} + +module_init(test_memcat_p_init); +module_exit(test_memcat_p_exit); + +MODULE_DESCRIPTION("Test cases for memcat_p() in lib/memcat_p.c"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1