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Diffstat (limited to '')
| -rw-r--r-- | lib/test_vmalloc.c | 624 |
1 files changed, 624 insertions, 0 deletions
diff --git a/lib/test_vmalloc.c b/lib/test_vmalloc.c new file mode 100644 index 000000000..5cf2fe9aa --- /dev/null +++ b/lib/test_vmalloc.c @@ -0,0 +1,624 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Test module for stress and analyze performance of vmalloc allocator. + * (C) 2018 Uladzislau Rezki (Sony) <urezki@gmail.com> + */ +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/vmalloc.h> +#include <linux/random.h> +#include <linux/kthread.h> +#include <linux/moduleparam.h> +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/rwsem.h> +#include <linux/mm.h> +#include <linux/rcupdate.h> +#include <linux/slab.h> + +#define __param(type, name, init, msg) \ + static type name = init; \ + module_param(name, type, 0444); \ + MODULE_PARM_DESC(name, msg) \ + +__param(bool, single_cpu_test, false, + "Use single first online CPU to run tests"); + +__param(bool, sequential_test_order, false, + "Use sequential stress tests order"); + +__param(int, test_repeat_count, 1, + "Set test repeat counter"); + +__param(int, test_loop_count, 1000000, + "Set test loop counter"); + +__param(int, run_test_mask, INT_MAX, + "Set tests specified in the mask.\n\n" + "\t\tid: 1, name: fix_size_alloc_test\n" + "\t\tid: 2, name: full_fit_alloc_test\n" + "\t\tid: 4, name: long_busy_list_alloc_test\n" + "\t\tid: 8, name: random_size_alloc_test\n" + "\t\tid: 16, name: fix_align_alloc_test\n" + "\t\tid: 32, name: random_size_align_alloc_test\n" + "\t\tid: 64, name: align_shift_alloc_test\n" + "\t\tid: 128, name: pcpu_alloc_test\n" + "\t\tid: 256, name: kvfree_rcu_1_arg_vmalloc_test\n" + "\t\tid: 512, name: kvfree_rcu_2_arg_vmalloc_test\n" + "\t\tid: 1024, name: kvfree_rcu_1_arg_slab_test\n" + "\t\tid: 2048, name: kvfree_rcu_2_arg_slab_test\n" + /* Add a new test case description here. */ +); + +/* + * Depends on single_cpu_test parameter. If it is true, then + * use first online CPU to trigger a test on, otherwise go with + * all online CPUs. + */ +static cpumask_t cpus_run_test_mask = CPU_MASK_NONE; + +/* + * Read write semaphore for synchronization of setup + * phase that is done in main thread and workers. + */ +static DECLARE_RWSEM(prepare_for_test_rwsem); + +/* + * Completion tracking for worker threads. + */ +static DECLARE_COMPLETION(test_all_done_comp); +static atomic_t test_n_undone = ATOMIC_INIT(0); + +static inline void +test_report_one_done(void) +{ + if (atomic_dec_and_test(&test_n_undone)) + complete(&test_all_done_comp); +} + +static int random_size_align_alloc_test(void) +{ + unsigned long size, align, rnd; + void *ptr; + int i; + + for (i = 0; i < test_loop_count; i++) { + get_random_bytes(&rnd, sizeof(rnd)); + + /* + * Maximum 1024 pages, if PAGE_SIZE is 4096. + */ + align = 1 << (rnd % 23); + + /* + * Maximum 10 pages. + */ + size = ((rnd % 10) + 1) * PAGE_SIZE; + + ptr = __vmalloc_node(size, align, GFP_KERNEL | __GFP_ZERO, 0, + __builtin_return_address(0)); + if (!ptr) + return -1; + + vfree(ptr); + } + + return 0; +} + +/* + * This test case is supposed to be failed. + */ +static int align_shift_alloc_test(void) +{ + unsigned long align; + void *ptr; + int i; + + for (i = 0; i < BITS_PER_LONG; i++) { + align = ((unsigned long) 1) << i; + + ptr = __vmalloc_node(PAGE_SIZE, align, GFP_KERNEL|__GFP_ZERO, 0, + __builtin_return_address(0)); + if (!ptr) + return -1; + + vfree(ptr); + } + + return 0; +} + +static int fix_align_alloc_test(void) +{ + void *ptr; + int i; + + for (i = 0; i < test_loop_count; i++) { + ptr = __vmalloc_node(5 * PAGE_SIZE, THREAD_ALIGN << 1, + GFP_KERNEL | __GFP_ZERO, 0, + __builtin_return_address(0)); + if (!ptr) + return -1; + + vfree(ptr); + } + + return 0; +} + +static int random_size_alloc_test(void) +{ + unsigned int n; + void *p; + int i; + + for (i = 0; i < test_loop_count; i++) { + get_random_bytes(&n, sizeof(i)); + n = (n % 100) + 1; + + p = vmalloc(n * PAGE_SIZE); + + if (!p) + return -1; + + *((__u8 *)p) = 1; + vfree(p); + } + + return 0; +} + +static int long_busy_list_alloc_test(void) +{ + void *ptr_1, *ptr_2; + void **ptr; + int rv = -1; + int i; + + ptr = vmalloc(sizeof(void *) * 15000); + if (!ptr) + return rv; + + for (i = 0; i < 15000; i++) + ptr[i] = vmalloc(1 * PAGE_SIZE); + + for (i = 0; i < test_loop_count; i++) { + ptr_1 = vmalloc(100 * PAGE_SIZE); + if (!ptr_1) + goto leave; + + ptr_2 = vmalloc(1 * PAGE_SIZE); + if (!ptr_2) { + vfree(ptr_1); + goto leave; + } + + *((__u8 *)ptr_1) = 0; + *((__u8 *)ptr_2) = 1; + + vfree(ptr_1); + vfree(ptr_2); + } + + /* Success */ + rv = 0; + +leave: + for (i = 0; i < 15000; i++) + vfree(ptr[i]); + + vfree(ptr); + return rv; +} + +static int full_fit_alloc_test(void) +{ + void **ptr, **junk_ptr, *tmp; + int junk_length; + int rv = -1; + int i; + + junk_length = fls(num_online_cpus()); + junk_length *= (32 * 1024 * 1024 / PAGE_SIZE); + + ptr = vmalloc(sizeof(void *) * junk_length); + if (!ptr) + return rv; + + junk_ptr = vmalloc(sizeof(void *) * junk_length); + if (!junk_ptr) { + vfree(ptr); + return rv; + } + + for (i = 0; i < junk_length; i++) { + ptr[i] = vmalloc(1 * PAGE_SIZE); + junk_ptr[i] = vmalloc(1 * PAGE_SIZE); + } + + for (i = 0; i < junk_length; i++) + vfree(junk_ptr[i]); + + for (i = 0; i < test_loop_count; i++) { + tmp = vmalloc(1 * PAGE_SIZE); + + if (!tmp) + goto error; + + *((__u8 *)tmp) = 1; + vfree(tmp); + } + + /* Success */ + rv = 0; + +error: + for (i = 0; i < junk_length; i++) + vfree(ptr[i]); + + vfree(ptr); + vfree(junk_ptr); + + return rv; +} + +static int fix_size_alloc_test(void) +{ + void *ptr; + int i; + + for (i = 0; i < test_loop_count; i++) { + ptr = vmalloc(3 * PAGE_SIZE); + + if (!ptr) + return -1; + + *((__u8 *)ptr) = 0; + + vfree(ptr); + } + + return 0; +} + +static int +pcpu_alloc_test(void) +{ + int rv = 0; +#ifndef CONFIG_NEED_PER_CPU_KM + void __percpu **pcpu; + size_t size, align; + int i; + + pcpu = vmalloc(sizeof(void __percpu *) * 35000); + if (!pcpu) + return -1; + + for (i = 0; i < 35000; i++) { + unsigned int r; + + get_random_bytes(&r, sizeof(i)); + size = (r % (PAGE_SIZE / 4)) + 1; + + /* + * Maximum PAGE_SIZE + */ + get_random_bytes(&r, sizeof(i)); + align = 1 << ((i % 11) + 1); + + pcpu[i] = __alloc_percpu(size, align); + if (!pcpu[i]) + rv = -1; + } + + for (i = 0; i < 35000; i++) + free_percpu(pcpu[i]); + + vfree(pcpu); +#endif + return rv; +} + +struct test_kvfree_rcu { + struct rcu_head rcu; + unsigned char array[20]; +}; + +static int +kvfree_rcu_1_arg_vmalloc_test(void) +{ + struct test_kvfree_rcu *p; + int i; + + for (i = 0; i < test_loop_count; i++) { + p = vmalloc(1 * PAGE_SIZE); + if (!p) + return -1; + + p->array[0] = 'a'; + kvfree_rcu(p); + } + + return 0; +} + +static int +kvfree_rcu_2_arg_vmalloc_test(void) +{ + struct test_kvfree_rcu *p; + int i; + + for (i = 0; i < test_loop_count; i++) { + p = vmalloc(1 * PAGE_SIZE); + if (!p) + return -1; + + p->array[0] = 'a'; + kvfree_rcu(p, rcu); + } + + return 0; +} + +static int +kvfree_rcu_1_arg_slab_test(void) +{ + struct test_kvfree_rcu *p; + int i; + + for (i = 0; i < test_loop_count; i++) { + p = kmalloc(sizeof(*p), GFP_KERNEL); + if (!p) + return -1; + + p->array[0] = 'a'; + kvfree_rcu(p); + } + + return 0; +} + +static int +kvfree_rcu_2_arg_slab_test(void) +{ + struct test_kvfree_rcu *p; + int i; + + for (i = 0; i < test_loop_count; i++) { + p = kmalloc(sizeof(*p), GFP_KERNEL); + if (!p) + return -1; + + p->array[0] = 'a'; + kvfree_rcu(p, rcu); + } + + return 0; +} + +struct test_case_desc { + const char *test_name; + int (*test_func)(void); +}; + +static struct test_case_desc test_case_array[] = { + { "fix_size_alloc_test", fix_size_alloc_test }, + { "full_fit_alloc_test", full_fit_alloc_test }, + { "long_busy_list_alloc_test", long_busy_list_alloc_test }, + { "random_size_alloc_test", random_size_alloc_test }, + { "fix_align_alloc_test", fix_align_alloc_test }, + { "random_size_align_alloc_test", random_size_align_alloc_test }, + { "align_shift_alloc_test", align_shift_alloc_test }, + { "pcpu_alloc_test", pcpu_alloc_test }, + { "kvfree_rcu_1_arg_vmalloc_test", kvfree_rcu_1_arg_vmalloc_test }, + { "kvfree_rcu_2_arg_vmalloc_test", kvfree_rcu_2_arg_vmalloc_test }, + { "kvfree_rcu_1_arg_slab_test", kvfree_rcu_1_arg_slab_test }, + { "kvfree_rcu_2_arg_slab_test", kvfree_rcu_2_arg_slab_test }, + /* Add a new test case here. */ +}; + +struct test_case_data { + int test_failed; + int test_passed; + u64 time; +}; + +/* Split it to get rid of: WARNING: line over 80 characters */ +static struct test_case_data + per_cpu_test_data[NR_CPUS][ARRAY_SIZE(test_case_array)]; + +static struct test_driver { + struct task_struct *task; + unsigned long start; + unsigned long stop; + int cpu; +} per_cpu_test_driver[NR_CPUS]; + +static void shuffle_array(int *arr, int n) +{ + unsigned int rnd; + int i, j, x; + + for (i = n - 1; i > 0; i--) { + get_random_bytes(&rnd, sizeof(rnd)); + + /* Cut the range. */ + j = rnd % i; + + /* Swap indexes. */ + x = arr[i]; + arr[i] = arr[j]; + arr[j] = x; + } +} + +static int test_func(void *private) +{ + struct test_driver *t = private; + int random_array[ARRAY_SIZE(test_case_array)]; + int index, i, j; + ktime_t kt; + u64 delta; + + if (set_cpus_allowed_ptr(current, cpumask_of(t->cpu)) < 0) + pr_err("Failed to set affinity to %d CPU\n", t->cpu); + + for (i = 0; i < ARRAY_SIZE(test_case_array); i++) + random_array[i] = i; + + if (!sequential_test_order) + shuffle_array(random_array, ARRAY_SIZE(test_case_array)); + + /* + * Block until initialization is done. + */ + down_read(&prepare_for_test_rwsem); + + t->start = get_cycles(); + for (i = 0; i < ARRAY_SIZE(test_case_array); i++) { + index = random_array[i]; + + /* + * Skip tests if run_test_mask has been specified. + */ + if (!((run_test_mask & (1 << index)) >> index)) + continue; + + kt = ktime_get(); + for (j = 0; j < test_repeat_count; j++) { + if (!test_case_array[index].test_func()) + per_cpu_test_data[t->cpu][index].test_passed++; + else + per_cpu_test_data[t->cpu][index].test_failed++; + } + + /* + * Take an average time that test took. + */ + delta = (u64) ktime_us_delta(ktime_get(), kt); + do_div(delta, (u32) test_repeat_count); + + per_cpu_test_data[t->cpu][index].time = delta; + } + t->stop = get_cycles(); + + up_read(&prepare_for_test_rwsem); + test_report_one_done(); + + /* + * Wait for the kthread_stop() call. + */ + while (!kthread_should_stop()) + msleep(10); + + return 0; +} + +static void +init_test_configurtion(void) +{ + /* + * Reset all data of all CPUs. + */ + memset(per_cpu_test_data, 0, sizeof(per_cpu_test_data)); + + if (single_cpu_test) + cpumask_set_cpu(cpumask_first(cpu_online_mask), + &cpus_run_test_mask); + else + cpumask_and(&cpus_run_test_mask, cpu_online_mask, + cpu_online_mask); + + if (test_repeat_count <= 0) + test_repeat_count = 1; + + if (test_loop_count <= 0) + test_loop_count = 1; +} + +static void do_concurrent_test(void) +{ + int cpu, ret; + + /* + * Set some basic configurations plus sanity check. + */ + init_test_configurtion(); + + /* + * Put on hold all workers. + */ + down_write(&prepare_for_test_rwsem); + + for_each_cpu(cpu, &cpus_run_test_mask) { + struct test_driver *t = &per_cpu_test_driver[cpu]; + + t->cpu = cpu; + t->task = kthread_run(test_func, t, "vmalloc_test/%d", cpu); + + if (!IS_ERR(t->task)) + /* Success. */ + atomic_inc(&test_n_undone); + else + pr_err("Failed to start kthread for %d CPU\n", cpu); + } + + /* + * Now let the workers do their job. + */ + up_write(&prepare_for_test_rwsem); + + /* + * Sleep quiet until all workers are done with 1 second + * interval. Since the test can take a lot of time we + * can run into a stack trace of the hung task. That is + * why we go with completion_timeout and HZ value. + */ + do { + ret = wait_for_completion_timeout(&test_all_done_comp, HZ); + } while (!ret); + + for_each_cpu(cpu, &cpus_run_test_mask) { + struct test_driver *t = &per_cpu_test_driver[cpu]; + int i; + + if (!IS_ERR(t->task)) + kthread_stop(t->task); + + for (i = 0; i < ARRAY_SIZE(test_case_array); i++) { + if (!((run_test_mask & (1 << i)) >> i)) + continue; + + pr_info( + "Summary: %s passed: %d failed: %d repeat: %d loops: %d avg: %llu usec\n", + test_case_array[i].test_name, + per_cpu_test_data[cpu][i].test_passed, + per_cpu_test_data[cpu][i].test_failed, + test_repeat_count, test_loop_count, + per_cpu_test_data[cpu][i].time); + } + + pr_info("All test took CPU%d=%lu cycles\n", + cpu, t->stop - t->start); + } +} + +static int vmalloc_test_init(void) +{ + do_concurrent_test(); + return -EAGAIN; /* Fail will directly unload the module */ +} + +static void vmalloc_test_exit(void) +{ +} + +module_init(vmalloc_test_init) +module_exit(vmalloc_test_exit) + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Uladzislau Rezki"); +MODULE_DESCRIPTION("vmalloc test module"); |