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-rw-r--r--lib/test_vmalloc.c569
1 files changed, 569 insertions, 0 deletions
diff --git a/lib/test_vmalloc.c b/lib/test_vmalloc.c
new file mode 100644
index 000000000..cf7780572
--- /dev/null
+++ b/lib/test_vmalloc.c
@@ -0,0 +1,569 @@
+// 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(int, nr_threads, 0,
+ "Number of workers to perform tests(min: 1 max: USHRT_MAX)");
+
+__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, nr_pages, 0,
+ "Set number of pages for fix_size_alloc_test(default: 1)");
+
+__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"
+ /* Add a new test case description here. */
+);
+
+/*
+ * 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;
+ unsigned int rnd;
+ void *ptr;
+ int i;
+
+ for (i = 0; i < test_loop_count; i++) {
+ rnd = get_random_u8();
+
+ /*
+ * 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++) {
+ n = prandom_u32_max(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((nr_pages > 0 ? nr_pages:1) * 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++) {
+ size = prandom_u32_max(PAGE_SIZE / 4) + 1;
+
+ /*
+ * Maximum PAGE_SIZE
+ */
+ align = 1 << (prandom_u32_max(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;
+}
+
+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 },
+ /* Add a new test case here. */
+};
+
+struct test_case_data {
+ int test_failed;
+ int test_passed;
+ u64 time;
+};
+
+static struct test_driver {
+ struct task_struct *task;
+ struct test_case_data data[ARRAY_SIZE(test_case_array)];
+
+ unsigned long start;
+ unsigned long stop;
+} *tdriver;
+
+static void shuffle_array(int *arr, int n)
+{
+ int i, j;
+
+ for (i = n - 1; i > 0; i--) {
+ /* Cut the range. */
+ j = prandom_u32_max(i);
+
+ /* Swap indexes. */
+ swap(arr[i], arr[j]);
+ }
+}
+
+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;
+
+ 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())
+ t->data[index].test_passed++;
+ else
+ t->data[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);
+
+ t->data[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 int
+init_test_configurtion(void)
+{
+ /*
+ * A maximum number of workers is defined as hard-coded
+ * value and set to USHRT_MAX. We add such gap just in
+ * case and for potential heavy stressing.
+ */
+ nr_threads = clamp(nr_threads, 1, (int) USHRT_MAX);
+
+ /* Allocate the space for test instances. */
+ tdriver = kvcalloc(nr_threads, sizeof(*tdriver), GFP_KERNEL);
+ if (tdriver == NULL)
+ return -1;
+
+ if (test_repeat_count <= 0)
+ test_repeat_count = 1;
+
+ if (test_loop_count <= 0)
+ test_loop_count = 1;
+
+ return 0;
+}
+
+static void do_concurrent_test(void)
+{
+ int i, ret;
+
+ /*
+ * Set some basic configurations plus sanity check.
+ */
+ ret = init_test_configurtion();
+ if (ret < 0)
+ return;
+
+ /*
+ * Put on hold all workers.
+ */
+ down_write(&prepare_for_test_rwsem);
+
+ for (i = 0; i < nr_threads; i++) {
+ struct test_driver *t = &tdriver[i];
+
+ t->task = kthread_run(test_func, t, "vmalloc_test/%d", i);
+
+ if (!IS_ERR(t->task))
+ /* Success. */
+ atomic_inc(&test_n_undone);
+ else
+ pr_err("Failed to start %d kthread\n", i);
+ }
+
+ /*
+ * 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 (i = 0; i < nr_threads; i++) {
+ struct test_driver *t = &tdriver[i];
+ int j;
+
+ if (!IS_ERR(t->task))
+ kthread_stop(t->task);
+
+ for (j = 0; j < ARRAY_SIZE(test_case_array); j++) {
+ if (!((run_test_mask & (1 << j)) >> j))
+ continue;
+
+ pr_info(
+ "Summary: %s passed: %d failed: %d repeat: %d loops: %d avg: %llu usec\n",
+ test_case_array[j].test_name,
+ t->data[j].test_passed,
+ t->data[j].test_failed,
+ test_repeat_count, test_loop_count,
+ t->data[j].time);
+ }
+
+ pr_info("All test took worker%d=%lu cycles\n",
+ i, t->stop - t->start);
+ }
+
+ kvfree(tdriver);
+}
+
+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");