diff options
Diffstat (limited to 'tools/testing/selftests/bpf/prog_tests')
3 files changed, 583 insertions, 2 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/btf_dump.c b/tools/testing/selftests/bpf/prog_tests/btf_dump.c index 5fce7008d1ff..a1bae92be1fc 100644 --- a/tools/testing/selftests/bpf/prog_tests/btf_dump.c +++ b/tools/testing/selftests/bpf/prog_tests/btf_dump.c @@ -764,8 +764,8 @@ static void test_btf_dump_struct_data(struct btf *btf, struct btf_dump *d, /* union with nested struct */ TEST_BTF_DUMP_DATA(btf, d, "union", str, union bpf_iter_link_info, BTF_F_COMPACT, - "(union bpf_iter_link_info){.map = (struct){.map_fd = (__u32)1,},}", - { .map = { .map_fd = 1 }}); + "(union bpf_iter_link_info){.map = (struct){.map_fd = (__u32)1,},.cgroup = (struct){.order = (enum bpf_cgroup_iter_order)BPF_ITER_SELF_ONLY,.cgroup_fd = (__u32)1,},}", + { .cgroup = { .order = 1, .cgroup_fd = 1, }}); /* struct skb with nested structs/unions; because type output is so * complex, we don't do a string comparison, just verify we return diff --git a/tools/testing/selftests/bpf/prog_tests/cgroup_hierarchical_stats.c b/tools/testing/selftests/bpf/prog_tests/cgroup_hierarchical_stats.c new file mode 100644 index 000000000000..101a6d70b863 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/cgroup_hierarchical_stats.c @@ -0,0 +1,357 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Functions to manage eBPF programs attached to cgroup subsystems + * + * Copyright 2022 Google LLC. + */ +#include <asm-generic/errno.h> +#include <errno.h> +#include <sys/types.h> +#include <sys/mount.h> +#include <sys/stat.h> +#include <unistd.h> + +#include <test_progs.h> +#include <bpf/libbpf.h> +#include <bpf/bpf.h> + +#include "cgroup_helpers.h" +#include "cgroup_hierarchical_stats.skel.h" + +#define PAGE_SIZE 4096 +#define MB(x) (x << 20) + +#define BPFFS_ROOT "/sys/fs/bpf/" +#define BPFFS_VMSCAN BPFFS_ROOT"vmscan/" + +#define CG_ROOT_NAME "root" +#define CG_ROOT_ID 1 + +#define CGROUP_PATH(p, n) {.path = p"/"n, .name = n} + +static struct { + const char *path, *name; + unsigned long long id; + int fd; +} cgroups[] = { + CGROUP_PATH("/", "test"), + CGROUP_PATH("/test", "child1"), + CGROUP_PATH("/test", "child2"), + CGROUP_PATH("/test/child1", "child1_1"), + CGROUP_PATH("/test/child1", "child1_2"), + CGROUP_PATH("/test/child2", "child2_1"), + CGROUP_PATH("/test/child2", "child2_2"), +}; + +#define N_CGROUPS ARRAY_SIZE(cgroups) +#define N_NON_LEAF_CGROUPS 3 + +static int root_cgroup_fd; +static bool mounted_bpffs; + +/* reads file at 'path' to 'buf', returns 0 on success. */ +static int read_from_file(const char *path, char *buf, size_t size) +{ + int fd, len; + + fd = open(path, O_RDONLY); + if (fd < 0) + return fd; + + len = read(fd, buf, size); + close(fd); + if (len < 0) + return len; + + buf[len] = 0; + return 0; +} + +/* mounts bpffs and mkdir for reading stats, returns 0 on success. */ +static int setup_bpffs(void) +{ + int err; + + /* Mount bpffs */ + err = mount("bpf", BPFFS_ROOT, "bpf", 0, NULL); + mounted_bpffs = !err; + if (ASSERT_FALSE(err && errno != EBUSY, "mount")) + return err; + + /* Create a directory to contain stat files in bpffs */ + err = mkdir(BPFFS_VMSCAN, 0755); + if (!ASSERT_OK(err, "mkdir")) + return err; + + return 0; +} + +static void cleanup_bpffs(void) +{ + /* Remove created directory in bpffs */ + ASSERT_OK(rmdir(BPFFS_VMSCAN), "rmdir "BPFFS_VMSCAN); + + /* Unmount bpffs, if it wasn't already mounted when we started */ + if (mounted_bpffs) + return; + + ASSERT_OK(umount(BPFFS_ROOT), "unmount bpffs"); +} + +/* sets up cgroups, returns 0 on success. */ +static int setup_cgroups(void) +{ + int i, fd, err; + + err = setup_cgroup_environment(); + if (!ASSERT_OK(err, "setup_cgroup_environment")) + return err; + + root_cgroup_fd = get_root_cgroup(); + if (!ASSERT_GE(root_cgroup_fd, 0, "get_root_cgroup")) + return root_cgroup_fd; + + for (i = 0; i < N_CGROUPS; i++) { + fd = create_and_get_cgroup(cgroups[i].path); + if (!ASSERT_GE(fd, 0, "create_and_get_cgroup")) + return fd; + + cgroups[i].fd = fd; + cgroups[i].id = get_cgroup_id(cgroups[i].path); + + /* + * Enable memcg controller for the entire hierarchy. + * Note that stats are collected for all cgroups in a hierarchy + * with memcg enabled anyway, but are only exposed for cgroups + * that have memcg enabled. + */ + if (i < N_NON_LEAF_CGROUPS) { + err = enable_controllers(cgroups[i].path, "memory"); + if (!ASSERT_OK(err, "enable_controllers")) + return err; + } + } + return 0; +} + +static void cleanup_cgroups(void) +{ + close(root_cgroup_fd); + for (int i = 0; i < N_CGROUPS; i++) + close(cgroups[i].fd); + cleanup_cgroup_environment(); +} + +/* Sets up cgroup hiearchary, returns 0 on success. */ +static int setup_hierarchy(void) +{ + return setup_bpffs() || setup_cgroups(); +} + +static void destroy_hierarchy(void) +{ + cleanup_cgroups(); + cleanup_bpffs(); +} + +static int reclaimer(const char *cgroup_path, size_t size) +{ + static char size_buf[128]; + char *buf, *ptr; + int err; + + /* Join cgroup in the parent process workdir */ + if (join_parent_cgroup(cgroup_path)) + return EACCES; + + /* Allocate memory */ + buf = malloc(size); + if (!buf) + return ENOMEM; + + /* Write to memory to make sure it's actually allocated */ + for (ptr = buf; ptr < buf + size; ptr += PAGE_SIZE) + *ptr = 1; + + /* Try to reclaim memory */ + snprintf(size_buf, 128, "%lu", size); + err = write_cgroup_file_parent(cgroup_path, "memory.reclaim", size_buf); + + free(buf); + /* memory.reclaim returns EAGAIN if the amount is not fully reclaimed */ + if (err && errno != EAGAIN) + return errno; + + return 0; +} + +static int induce_vmscan(void) +{ + int i, status; + + /* + * In every leaf cgroup, run a child process that allocates some memory + * and attempts to reclaim some of it. + */ + for (i = N_NON_LEAF_CGROUPS; i < N_CGROUPS; i++) { + pid_t pid; + + /* Create reclaimer child */ + pid = fork(); + if (pid == 0) { + status = reclaimer(cgroups[i].path, MB(5)); + exit(status); + } + + /* Cleanup reclaimer child */ + waitpid(pid, &status, 0); + ASSERT_TRUE(WIFEXITED(status), "reclaimer exited"); + ASSERT_EQ(WEXITSTATUS(status), 0, "reclaim exit code"); + } + return 0; +} + +static unsigned long long +get_cgroup_vmscan_delay(unsigned long long cgroup_id, const char *file_name) +{ + unsigned long long vmscan = 0, id = 0; + static char buf[128], path[128]; + + /* For every cgroup, read the file generated by cgroup_iter */ + snprintf(path, 128, "%s%s", BPFFS_VMSCAN, file_name); + if (!ASSERT_OK(read_from_file(path, buf, 128), "read cgroup_iter")) + return 0; + + /* Check the output file formatting */ + ASSERT_EQ(sscanf(buf, "cg_id: %llu, total_vmscan_delay: %llu\n", + &id, &vmscan), 2, "output format"); + + /* Check that the cgroup_id is displayed correctly */ + ASSERT_EQ(id, cgroup_id, "cgroup_id"); + /* Check that the vmscan reading is non-zero */ + ASSERT_GT(vmscan, 0, "vmscan_reading"); + return vmscan; +} + +static void check_vmscan_stats(void) +{ + unsigned long long vmscan_readings[N_CGROUPS], vmscan_root; + int i; + + for (i = 0; i < N_CGROUPS; i++) { + vmscan_readings[i] = get_cgroup_vmscan_delay(cgroups[i].id, + cgroups[i].name); + } + + /* Read stats for root too */ + vmscan_root = get_cgroup_vmscan_delay(CG_ROOT_ID, CG_ROOT_NAME); + + /* Check that child1 == child1_1 + child1_2 */ + ASSERT_EQ(vmscan_readings[1], vmscan_readings[3] + vmscan_readings[4], + "child1_vmscan"); + /* Check that child2 == child2_1 + child2_2 */ + ASSERT_EQ(vmscan_readings[2], vmscan_readings[5] + vmscan_readings[6], + "child2_vmscan"); + /* Check that test == child1 + child2 */ + ASSERT_EQ(vmscan_readings[0], vmscan_readings[1] + vmscan_readings[2], + "test_vmscan"); + /* Check that root >= test */ + ASSERT_GE(vmscan_root, vmscan_readings[1], "root_vmscan"); +} + +/* Creates iter link and pins in bpffs, returns 0 on success, -errno on failure. + */ +static int setup_cgroup_iter(struct cgroup_hierarchical_stats *obj, + int cgroup_fd, const char *file_name) +{ + DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts); + union bpf_iter_link_info linfo = {}; + struct bpf_link *link; + static char path[128]; + int err; + + /* + * Create an iter link, parameterized by cgroup_fd. We only want to + * traverse one cgroup, so set the traversal order to "self". + */ + linfo.cgroup.cgroup_fd = cgroup_fd; + linfo.cgroup.order = BPF_ITER_SELF_ONLY; + opts.link_info = &linfo; + opts.link_info_len = sizeof(linfo); + link = bpf_program__attach_iter(obj->progs.dump_vmscan, &opts); + if (!ASSERT_OK_PTR(link, "attach_iter")) + return -EFAULT; + + /* Pin the link to a bpffs file */ + snprintf(path, 128, "%s%s", BPFFS_VMSCAN, file_name); + err = bpf_link__pin(link, path); + ASSERT_OK(err, "pin cgroup_iter"); + + /* Remove the link, leaving only the ref held by the pinned file */ + bpf_link__destroy(link); + return err; +} + +/* Sets up programs for collecting stats, returns 0 on success. */ +static int setup_progs(struct cgroup_hierarchical_stats **skel) +{ + int i, err; + + *skel = cgroup_hierarchical_stats__open_and_load(); + if (!ASSERT_OK_PTR(*skel, "open_and_load")) + return 1; + + /* Attach cgroup_iter program that will dump the stats to cgroups */ + for (i = 0; i < N_CGROUPS; i++) { + err = setup_cgroup_iter(*skel, cgroups[i].fd, cgroups[i].name); + if (!ASSERT_OK(err, "setup_cgroup_iter")) + return err; + } + + /* Also dump stats for root */ + err = setup_cgroup_iter(*skel, root_cgroup_fd, CG_ROOT_NAME); + if (!ASSERT_OK(err, "setup_cgroup_iter")) + return err; + + bpf_program__set_autoattach((*skel)->progs.dump_vmscan, false); + err = cgroup_hierarchical_stats__attach(*skel); + if (!ASSERT_OK(err, "attach")) + return err; + + return 0; +} + +static void destroy_progs(struct cgroup_hierarchical_stats *skel) +{ + static char path[128]; + int i; + + for (i = 0; i < N_CGROUPS; i++) { + /* Delete files in bpffs that cgroup_iters are pinned in */ + snprintf(path, 128, "%s%s", BPFFS_VMSCAN, + cgroups[i].name); + ASSERT_OK(remove(path), "remove cgroup_iter pin"); + } + + /* Delete root file in bpffs */ + snprintf(path, 128, "%s%s", BPFFS_VMSCAN, CG_ROOT_NAME); + ASSERT_OK(remove(path), "remove cgroup_iter root pin"); + cgroup_hierarchical_stats__destroy(skel); +} + +void test_cgroup_hierarchical_stats(void) +{ + struct cgroup_hierarchical_stats *skel = NULL; + + if (setup_hierarchy()) + goto hierarchy_cleanup; + if (setup_progs(&skel)) + goto cleanup; + if (induce_vmscan()) + goto cleanup; + check_vmscan_stats(); +cleanup: + destroy_progs(skel); +hierarchy_cleanup: + destroy_hierarchy(); +} diff --git a/tools/testing/selftests/bpf/prog_tests/cgroup_iter.c b/tools/testing/selftests/bpf/prog_tests/cgroup_iter.c new file mode 100644 index 000000000000..38958c37b9ce --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/cgroup_iter.c @@ -0,0 +1,224 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2022 Google */ + +#include <test_progs.h> +#include <bpf/libbpf.h> +#include <bpf/btf.h> +#include "cgroup_iter.skel.h" +#include "cgroup_helpers.h" + +#define ROOT 0 +#define PARENT 1 +#define CHILD1 2 +#define CHILD2 3 +#define NUM_CGROUPS 4 + +#define PROLOGUE "prologue\n" +#define EPILOGUE "epilogue\n" + +static const char *cg_path[] = { + "/", "/parent", "/parent/child1", "/parent/child2" +}; + +static int cg_fd[] = {-1, -1, -1, -1}; +static unsigned long long cg_id[] = {0, 0, 0, 0}; +static char expected_output[64]; + +static int setup_cgroups(void) +{ + int fd, i = 0; + + for (i = 0; i < NUM_CGROUPS; i++) { + fd = create_and_get_cgroup(cg_path[i]); + if (fd < 0) + return fd; + + cg_fd[i] = fd; + cg_id[i] = get_cgroup_id(cg_path[i]); + } + return 0; +} + +static void cleanup_cgroups(void) +{ + int i; + + for (i = 0; i < NUM_CGROUPS; i++) + close(cg_fd[i]); +} + +static void read_from_cgroup_iter(struct bpf_program *prog, int cgroup_fd, + int order, const char *testname) +{ + DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts); + union bpf_iter_link_info linfo; + struct bpf_link *link; + int len, iter_fd; + static char buf[128]; + size_t left; + char *p; + + memset(&linfo, 0, sizeof(linfo)); + linfo.cgroup.cgroup_fd = cgroup_fd; + linfo.cgroup.order = order; + opts.link_info = &linfo; + opts.link_info_len = sizeof(linfo); + + link = bpf_program__attach_iter(prog, &opts); + if (!ASSERT_OK_PTR(link, "attach_iter")) + return; + + iter_fd = bpf_iter_create(bpf_link__fd(link)); + if (iter_fd < 0) + goto free_link; + + memset(buf, 0, sizeof(buf)); + left = ARRAY_SIZE(buf); + p = buf; + while ((len = read(iter_fd, p, left)) > 0) { + p += len; + left -= len; + } + + ASSERT_STREQ(buf, expected_output, testname); + + /* read() after iter finishes should be ok. */ + if (len == 0) + ASSERT_OK(read(iter_fd, buf, sizeof(buf)), "second_read"); + + close(iter_fd); +free_link: + bpf_link__destroy(link); +} + +/* Invalid cgroup. */ +static void test_invalid_cgroup(struct cgroup_iter *skel) +{ + DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts); + union bpf_iter_link_info linfo; + struct bpf_link *link; + + memset(&linfo, 0, sizeof(linfo)); + linfo.cgroup.cgroup_fd = (__u32)-1; + opts.link_info = &linfo; + opts.link_info_len = sizeof(linfo); + + link = bpf_program__attach_iter(skel->progs.cgroup_id_printer, &opts); + ASSERT_ERR_PTR(link, "attach_iter"); + bpf_link__destroy(link); +} + +/* Specifying both cgroup_fd and cgroup_id is invalid. */ +static void test_invalid_cgroup_spec(struct cgroup_iter *skel) +{ + DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts); + union bpf_iter_link_info linfo; + struct bpf_link *link; + + memset(&linfo, 0, sizeof(linfo)); + linfo.cgroup.cgroup_fd = (__u32)cg_fd[PARENT]; + linfo.cgroup.cgroup_id = (__u64)cg_id[PARENT]; + opts.link_info = &linfo; + opts.link_info_len = sizeof(linfo); + + link = bpf_program__attach_iter(skel->progs.cgroup_id_printer, &opts); + ASSERT_ERR_PTR(link, "attach_iter"); + bpf_link__destroy(link); +} + +/* Preorder walk prints parent and child in order. */ +static void test_walk_preorder(struct cgroup_iter *skel) +{ + snprintf(expected_output, sizeof(expected_output), + PROLOGUE "%8llu\n%8llu\n%8llu\n" EPILOGUE, + cg_id[PARENT], cg_id[CHILD1], cg_id[CHILD2]); + + read_from_cgroup_iter(skel->progs.cgroup_id_printer, cg_fd[PARENT], + BPF_ITER_DESCENDANTS_PRE, "preorder"); +} + +/* Postorder walk prints child and parent in order. */ +static void test_walk_postorder(struct cgroup_iter *skel) +{ + snprintf(expected_output, sizeof(expected_output), + PROLOGUE "%8llu\n%8llu\n%8llu\n" EPILOGUE, + cg_id[CHILD1], cg_id[CHILD2], cg_id[PARENT]); + + read_from_cgroup_iter(skel->progs.cgroup_id_printer, cg_fd[PARENT], + BPF_ITER_DESCENDANTS_POST, "postorder"); +} + +/* Walking parents prints parent and then root. */ +static void test_walk_ancestors_up(struct cgroup_iter *skel) +{ + /* terminate the walk when ROOT is met. */ + skel->bss->terminal_cgroup = cg_id[ROOT]; + + snprintf(expected_output, sizeof(expected_output), + PROLOGUE "%8llu\n%8llu\n" EPILOGUE, + cg_id[PARENT], cg_id[ROOT]); + + read_from_cgroup_iter(skel->progs.cgroup_id_printer, cg_fd[PARENT], + BPF_ITER_ANCESTORS_UP, "ancestors_up"); + + skel->bss->terminal_cgroup = 0; +} + +/* Early termination prints parent only. */ +static void test_early_termination(struct cgroup_iter *skel) +{ + /* terminate the walk after the first element is processed. */ + skel->bss->terminate_early = 1; + + snprintf(expected_output, sizeof(expected_output), + PROLOGUE "%8llu\n" EPILOGUE, cg_id[PARENT]); + + read_from_cgroup_iter(skel->progs.cgroup_id_printer, cg_fd[PARENT], + BPF_ITER_DESCENDANTS_PRE, "early_termination"); + + skel->bss->terminate_early = 0; +} + +/* Waling self prints self only. */ +static void test_walk_self_only(struct cgroup_iter *skel) +{ + snprintf(expected_output, sizeof(expected_output), + PROLOGUE "%8llu\n" EPILOGUE, cg_id[PARENT]); + + read_from_cgroup_iter(skel->progs.cgroup_id_printer, cg_fd[PARENT], + BPF_ITER_SELF_ONLY, "self_only"); +} + +void test_cgroup_iter(void) +{ + struct cgroup_iter *skel = NULL; + + if (setup_cgroup_environment()) + return; + + if (setup_cgroups()) + goto out; + + skel = cgroup_iter__open_and_load(); + if (!ASSERT_OK_PTR(skel, "cgroup_iter__open_and_load")) + goto out; + + if (test__start_subtest("cgroup_iter__invalid_cgroup")) + test_invalid_cgroup(skel); + if (test__start_subtest("cgroup_iter__invalid_cgroup_spec")) + test_invalid_cgroup_spec(skel); + if (test__start_subtest("cgroup_iter__preorder")) + test_walk_preorder(skel); + if (test__start_subtest("cgroup_iter__postorder")) + test_walk_postorder(skel); + if (test__start_subtest("cgroup_iter__ancestors_up_walk")) + test_walk_ancestors_up(skel); + if (test__start_subtest("cgroup_iter__early_termination")) + test_early_termination(skel); + if (test__start_subtest("cgroup_iter__self_only")) + test_walk_self_only(skel); +out: + cgroup_iter__destroy(skel); + cleanup_cgroups(); + cleanup_cgroup_environment(); +} |