1 files changed, 551 insertions, 0 deletions

diff --git a/lib/test_vmalloc.c b/lib/test_vmalloc.c
new file mode 100644
index 000000000000..83cdcaa82bf6
--- /dev/null
+++ b/lib/test_vmalloc.c
@@ -0,0 +1,551 @@
+// 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>
+
+#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"
+                /* 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_range(size, align,
+                   VMALLOC_START, VMALLOC_END,
+                   GFP_KERNEL | __GFP_ZERO,
+                   PAGE_KERNEL,
+                   0, 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_range(PAGE_SIZE, align,
+                        VMALLOC_START, VMALLOC_END,
+                        GFP_KERNEL | __GFP_ZERO,
+                        PAGE_KERNEL,
+                        0, 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_range(5 * PAGE_SIZE,
+                        THREAD_ALIGN << 1,
+                        VMALLOC_START, VMALLOC_END,
+                        GFP_KERNEL | __GFP_ZERO,
+                        PAGE_KERNEL,
+                        0, 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_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 },
+        /* 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;
+        cpumask_t newmask = CPU_MASK_NONE;
+        int random_array[ARRAY_SIZE(test_case_array)];
+        int index, i, j, ret;
+        ktime_t kt;
+        u64 delta;
+
+        cpumask_set_cpu(t->cpu, &newmask);
+        set_cpus_allowed_ptr(current, &newmask);
+
+        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++) {
+                        ret = test_case_array[index].test_func();
+                        if (!ret)
+                                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");