From 73d9eb340d2b95e0e86a656a7f3157c137f10129 Mon Sep 17 00:00:00 2001 From: Yafang Shao Date: Wed, 6 Dec 2023 11:53:24 +0000 Subject: [PATCH 1/3] bpf: Enable bpf_cgrp_storage for cgroup1 non-attach case In the current cgroup1 environment, associating operations between cgroups and applications in a BPF program requires storing a mapping of cgroup_id to application either in a hash map or maintaining it in userspace. However, by enabling bpf_cgrp_storage for cgroup1, it becomes possible to conveniently store application-specific information in cgroup-local storage and utilize it within BPF programs. Furthermore, enabling this feature for cgroup1 involves minor modifications for the non-attach case, streamlining the process. However, when it comes to enabling this functionality for the cgroup1 attach case, it presents challenges. Therefore, the decision is to focus on enabling it solely for the cgroup1 non-attach case at present. If attempting to attach to a cgroup1 fd, the operation will simply fail with the error code -EBADF. Signed-off-by: Yafang Shao Acked-by: Tejun Heo Acked-by: Yonghong Song Link: https://lore.kernel.org/r/20231206115326.4295-2-laoar.shao@gmail.com Signed-off-by: Martin KaFai Lau --- kernel/bpf/bpf_cgrp_storage.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/kernel/bpf/bpf_cgrp_storage.c b/kernel/bpf/bpf_cgrp_storage.c index d44fe8dd9732..28efd0a3f220 100644 --- a/kernel/bpf/bpf_cgrp_storage.c +++ b/kernel/bpf/bpf_cgrp_storage.c @@ -82,7 +82,7 @@ static void *bpf_cgrp_storage_lookup_elem(struct bpf_map *map, void *key) int fd; fd = *(int *)key; - cgroup = cgroup_get_from_fd(fd); + cgroup = cgroup_v1v2_get_from_fd(fd); if (IS_ERR(cgroup)) return ERR_CAST(cgroup); @@ -101,7 +101,7 @@ static long bpf_cgrp_storage_update_elem(struct bpf_map *map, void *key, int fd; fd = *(int *)key; - cgroup = cgroup_get_from_fd(fd); + cgroup = cgroup_v1v2_get_from_fd(fd); if (IS_ERR(cgroup)) return PTR_ERR(cgroup); @@ -131,7 +131,7 @@ static long bpf_cgrp_storage_delete_elem(struct bpf_map *map, void *key) int err, fd; fd = *(int *)key; - cgroup = cgroup_get_from_fd(fd); + cgroup = cgroup_v1v2_get_from_fd(fd); if (IS_ERR(cgroup)) return PTR_ERR(cgroup); From f4199271dae12ae407fa739e7012914ea6b3f37b Mon Sep 17 00:00:00 2001 From: Yafang Shao Date: Wed, 6 Dec 2023 11:53:25 +0000 Subject: [PATCH 2/3] selftests/bpf: Add a new cgroup helper open_classid() This new helper allows us to obtain the fd of a net_cls cgroup, which will be utilized in the subsequent patch. Signed-off-by: Yafang Shao Acked-by: Tejun Heo Acked-by: Yonghong Song Link: https://lore.kernel.org/r/20231206115326.4295-3-laoar.shao@gmail.com Signed-off-by: Martin KaFai Lau --- tools/testing/selftests/bpf/cgroup_helpers.c | 16 ++++++++++++++++ tools/testing/selftests/bpf/cgroup_helpers.h | 1 + 2 files changed, 17 insertions(+) diff --git a/tools/testing/selftests/bpf/cgroup_helpers.c b/tools/testing/selftests/bpf/cgroup_helpers.c index 5aa133bf3688..19be9c63d5e8 100644 --- a/tools/testing/selftests/bpf/cgroup_helpers.c +++ b/tools/testing/selftests/bpf/cgroup_helpers.c @@ -689,3 +689,19 @@ int get_cgroup1_hierarchy_id(const char *subsys_name) fclose(file); return found ? id : -1; } + +/** + * open_classid() - Open a cgroupv1 net_cls classid + * + * This function expects the cgroup work dir to be already created, as we + * open it here. + * + * On success, it returns the file descriptor. On failure it returns -1. + */ +int open_classid(void) +{ + char cgroup_workdir[PATH_MAX + 1]; + + format_classid_path(cgroup_workdir); + return open(cgroup_workdir, O_RDONLY); +} diff --git a/tools/testing/selftests/bpf/cgroup_helpers.h b/tools/testing/selftests/bpf/cgroup_helpers.h index ee053641c026..502845160d88 100644 --- a/tools/testing/selftests/bpf/cgroup_helpers.h +++ b/tools/testing/selftests/bpf/cgroup_helpers.h @@ -33,6 +33,7 @@ void cleanup_cgroup_environment(void); int set_classid(void); int join_classid(void); unsigned long long get_classid_cgroup_id(void); +int open_classid(void); int setup_classid_environment(void); void cleanup_classid_environment(void); From a2c6380b17b6339bfedc98d253b6d85e7014953b Mon Sep 17 00:00:00 2001 From: Yafang Shao Date: Wed, 6 Dec 2023 11:53:26 +0000 Subject: [PATCH 3/3] selftests/bpf: Add selftests for cgroup1 local storage Expanding the test coverage from cgroup2 to include cgroup1. The result as follows, Already existing test cases for cgroup2: #48/1 cgrp_local_storage/tp_btf:OK #48/2 cgrp_local_storage/attach_cgroup:OK #48/3 cgrp_local_storage/recursion:OK #48/4 cgrp_local_storage/negative:OK #48/5 cgrp_local_storage/cgroup_iter_sleepable:OK #48/6 cgrp_local_storage/yes_rcu_lock:OK #48/7 cgrp_local_storage/no_rcu_lock:OK Expanded test cases for cgroup1: #48/8 cgrp_local_storage/cgrp1_tp_btf:OK #48/9 cgrp_local_storage/cgrp1_recursion:OK #48/10 cgrp_local_storage/cgrp1_negative:OK #48/11 cgrp_local_storage/cgrp1_iter_sleepable:OK #48/12 cgrp_local_storage/cgrp1_yes_rcu_lock:OK #48/13 cgrp_local_storage/cgrp1_no_rcu_lock:OK Summary: #48 cgrp_local_storage:OK Summary: 1/13 PASSED, 0 SKIPPED, 0 FAILED Signed-off-by: Yafang Shao Acked-by: Tejun Heo Acked-by: Yonghong Song Link: https://lore.kernel.org/r/20231206115326.4295-4-laoar.shao@gmail.com Signed-off-by: Martin KaFai Lau --- .../bpf/prog_tests/cgrp_local_storage.c | 98 ++++++++++++++++- .../selftests/bpf/progs/cgrp_ls_recursion.c | 92 ++++++++++++---- .../selftests/bpf/progs/cgrp_ls_sleepable.c | 61 +++++++++-- .../selftests/bpf/progs/cgrp_ls_tp_btf.c | 100 ++++++++++++------ 4 files changed, 291 insertions(+), 60 deletions(-) diff --git a/tools/testing/selftests/bpf/prog_tests/cgrp_local_storage.c b/tools/testing/selftests/bpf/prog_tests/cgrp_local_storage.c index 63e776f4176e..747761572098 100644 --- a/tools/testing/selftests/bpf/prog_tests/cgrp_local_storage.c +++ b/tools/testing/selftests/bpf/prog_tests/cgrp_local_storage.c @@ -19,6 +19,21 @@ struct socket_cookie { __u64 cookie_value; }; +static bool is_cgroup1; +static int target_hid; + +#define CGROUP_MODE_SET(skel) \ +{ \ + skel->bss->is_cgroup1 = is_cgroup1; \ + skel->bss->target_hid = target_hid; \ +} + +static void cgroup_mode_value_init(bool cgroup, int hid) +{ + is_cgroup1 = cgroup; + target_hid = hid; +} + static void test_tp_btf(int cgroup_fd) { struct cgrp_ls_tp_btf *skel; @@ -29,6 +44,8 @@ static void test_tp_btf(int cgroup_fd) if (!ASSERT_OK_PTR(skel, "skel_open_and_load")) return; + CGROUP_MODE_SET(skel); + /* populate a value in map_b */ err = bpf_map_update_elem(bpf_map__fd(skel->maps.map_b), &cgroup_fd, &val1, BPF_ANY); if (!ASSERT_OK(err, "map_update_elem")) @@ -130,6 +147,8 @@ static void test_recursion(int cgroup_fd) if (!ASSERT_OK_PTR(skel, "skel_open_and_load")) return; + CGROUP_MODE_SET(skel); + err = cgrp_ls_recursion__attach(skel); if (!ASSERT_OK(err, "skel_attach")) goto out; @@ -165,6 +184,8 @@ static void test_cgroup_iter_sleepable(int cgroup_fd, __u64 cgroup_id) if (!ASSERT_OK_PTR(skel, "skel_open")) return; + CGROUP_MODE_SET(skel); + bpf_program__set_autoload(skel->progs.cgroup_iter, true); err = cgrp_ls_sleepable__load(skel); if (!ASSERT_OK(err, "skel_load")) @@ -202,6 +223,7 @@ static void test_yes_rcu_lock(__u64 cgroup_id) if (!ASSERT_OK_PTR(skel, "skel_open")) return; + CGROUP_MODE_SET(skel); skel->bss->target_pid = syscall(SYS_gettid); bpf_program__set_autoload(skel->progs.yes_rcu_lock, true); @@ -229,6 +251,8 @@ static void test_no_rcu_lock(void) if (!ASSERT_OK_PTR(skel, "skel_open")) return; + CGROUP_MODE_SET(skel); + bpf_program__set_autoload(skel->progs.no_rcu_lock, true); err = cgrp_ls_sleepable__load(skel); ASSERT_ERR(err, "skel_load"); @@ -236,7 +260,25 @@ static void test_no_rcu_lock(void) cgrp_ls_sleepable__destroy(skel); } -void test_cgrp_local_storage(void) +static void test_cgrp1_no_rcu_lock(void) +{ + struct cgrp_ls_sleepable *skel; + int err; + + skel = cgrp_ls_sleepable__open(); + if (!ASSERT_OK_PTR(skel, "skel_open")) + return; + + CGROUP_MODE_SET(skel); + + bpf_program__set_autoload(skel->progs.cgrp1_no_rcu_lock, true); + err = cgrp_ls_sleepable__load(skel); + ASSERT_OK(err, "skel_load"); + + cgrp_ls_sleepable__destroy(skel); +} + +static void cgrp2_local_storage(void) { __u64 cgroup_id; int cgroup_fd; @@ -245,6 +287,8 @@ void test_cgrp_local_storage(void) if (!ASSERT_GE(cgroup_fd, 0, "join_cgroup /cgrp_local_storage")) return; + cgroup_mode_value_init(0, -1); + cgroup_id = get_cgroup_id("/cgrp_local_storage"); if (test__start_subtest("tp_btf")) test_tp_btf(cgroup_fd); @@ -263,3 +307,55 @@ void test_cgrp_local_storage(void) close(cgroup_fd); } + +static void cgrp1_local_storage(void) +{ + int cgrp1_fd, cgrp1_hid, cgrp1_id, err; + + /* Setup cgroup1 hierarchy */ + err = setup_classid_environment(); + if (!ASSERT_OK(err, "setup_classid_environment")) + return; + + err = join_classid(); + if (!ASSERT_OK(err, "join_cgroup1")) + goto cleanup; + + cgrp1_fd = open_classid(); + if (!ASSERT_GE(cgrp1_fd, 0, "cgroup1 fd")) + goto cleanup; + + cgrp1_id = get_classid_cgroup_id(); + if (!ASSERT_GE(cgrp1_id, 0, "cgroup1 id")) + goto close_fd; + + cgrp1_hid = get_cgroup1_hierarchy_id("net_cls"); + if (!ASSERT_GE(cgrp1_hid, 0, "cgroup1 hid")) + goto close_fd; + + cgroup_mode_value_init(1, cgrp1_hid); + + if (test__start_subtest("cgrp1_tp_btf")) + test_tp_btf(cgrp1_fd); + if (test__start_subtest("cgrp1_recursion")) + test_recursion(cgrp1_fd); + if (test__start_subtest("cgrp1_negative")) + test_negative(); + if (test__start_subtest("cgrp1_iter_sleepable")) + test_cgroup_iter_sleepable(cgrp1_fd, cgrp1_id); + if (test__start_subtest("cgrp1_yes_rcu_lock")) + test_yes_rcu_lock(cgrp1_id); + if (test__start_subtest("cgrp1_no_rcu_lock")) + test_cgrp1_no_rcu_lock(); + +close_fd: + close(cgrp1_fd); +cleanup: + cleanup_classid_environment(); +} + +void test_cgrp_local_storage(void) +{ + cgrp2_local_storage(); + cgrp1_local_storage(); +} diff --git a/tools/testing/selftests/bpf/progs/cgrp_ls_recursion.c b/tools/testing/selftests/bpf/progs/cgrp_ls_recursion.c index a043d8fefdac..610c2427fd93 100644 --- a/tools/testing/selftests/bpf/progs/cgrp_ls_recursion.c +++ b/tools/testing/selftests/bpf/progs/cgrp_ls_recursion.c @@ -21,50 +21,100 @@ struct { __type(value, long); } map_b SEC(".maps"); +int target_hid = 0; +bool is_cgroup1 = 0; + +struct cgroup *bpf_task_get_cgroup1(struct task_struct *task, int hierarchy_id) __ksym; +void bpf_cgroup_release(struct cgroup *cgrp) __ksym; + +static void __on_lookup(struct cgroup *cgrp) +{ + bpf_cgrp_storage_delete(&map_a, cgrp); + bpf_cgrp_storage_delete(&map_b, cgrp); +} + SEC("fentry/bpf_local_storage_lookup") int BPF_PROG(on_lookup) { struct task_struct *task = bpf_get_current_task_btf(); + struct cgroup *cgrp; - bpf_cgrp_storage_delete(&map_a, task->cgroups->dfl_cgrp); - bpf_cgrp_storage_delete(&map_b, task->cgroups->dfl_cgrp); + if (is_cgroup1) { + cgrp = bpf_task_get_cgroup1(task, target_hid); + if (!cgrp) + return 0; + + __on_lookup(cgrp); + bpf_cgroup_release(cgrp); + return 0; + } + + __on_lookup(task->cgroups->dfl_cgrp); return 0; } +static void __on_update(struct cgroup *cgrp) +{ + long *ptr; + + ptr = bpf_cgrp_storage_get(&map_a, cgrp, 0, BPF_LOCAL_STORAGE_GET_F_CREATE); + if (ptr) + *ptr += 1; + + ptr = bpf_cgrp_storage_get(&map_b, cgrp, 0, BPF_LOCAL_STORAGE_GET_F_CREATE); + if (ptr) + *ptr += 1; +} + SEC("fentry/bpf_local_storage_update") int BPF_PROG(on_update) { struct task_struct *task = bpf_get_current_task_btf(); + struct cgroup *cgrp; + + if (is_cgroup1) { + cgrp = bpf_task_get_cgroup1(task, target_hid); + if (!cgrp) + return 0; + + __on_update(cgrp); + bpf_cgroup_release(cgrp); + return 0; + } + + __on_update(task->cgroups->dfl_cgrp); + return 0; +} + +static void __on_enter(struct pt_regs *regs, long id, struct cgroup *cgrp) +{ long *ptr; - ptr = bpf_cgrp_storage_get(&map_a, task->cgroups->dfl_cgrp, 0, - BPF_LOCAL_STORAGE_GET_F_CREATE); + ptr = bpf_cgrp_storage_get(&map_a, cgrp, 0, BPF_LOCAL_STORAGE_GET_F_CREATE); if (ptr) - *ptr += 1; + *ptr = 200; - ptr = bpf_cgrp_storage_get(&map_b, task->cgroups->dfl_cgrp, 0, - BPF_LOCAL_STORAGE_GET_F_CREATE); + ptr = bpf_cgrp_storage_get(&map_b, cgrp, 0, BPF_LOCAL_STORAGE_GET_F_CREATE); if (ptr) - *ptr += 1; - - return 0; + *ptr = 100; } SEC("tp_btf/sys_enter") int BPF_PROG(on_enter, struct pt_regs *regs, long id) { - struct task_struct *task; - long *ptr; + struct task_struct *task = bpf_get_current_task_btf(); + struct cgroup *cgrp; - task = bpf_get_current_task_btf(); - ptr = bpf_cgrp_storage_get(&map_a, task->cgroups->dfl_cgrp, 0, - BPF_LOCAL_STORAGE_GET_F_CREATE); - if (ptr) - *ptr = 200; + if (is_cgroup1) { + cgrp = bpf_task_get_cgroup1(task, target_hid); + if (!cgrp) + return 0; - ptr = bpf_cgrp_storage_get(&map_b, task->cgroups->dfl_cgrp, 0, - BPF_LOCAL_STORAGE_GET_F_CREATE); - if (ptr) - *ptr = 100; + __on_enter(regs, id, cgrp); + bpf_cgroup_release(cgrp); + return 0; + } + + __on_enter(regs, id, task->cgroups->dfl_cgrp); return 0; } diff --git a/tools/testing/selftests/bpf/progs/cgrp_ls_sleepable.c b/tools/testing/selftests/bpf/progs/cgrp_ls_sleepable.c index 4c7844e1dbfa..facedd8b8250 100644 --- a/tools/testing/selftests/bpf/progs/cgrp_ls_sleepable.c +++ b/tools/testing/selftests/bpf/progs/cgrp_ls_sleepable.c @@ -17,7 +17,11 @@ struct { __u32 target_pid; __u64 cgroup_id; +int target_hid; +bool is_cgroup1; +struct cgroup *bpf_task_get_cgroup1(struct task_struct *task, int hierarchy_id) __ksym; +void bpf_cgroup_release(struct cgroup *cgrp) __ksym; void bpf_rcu_read_lock(void) __ksym; void bpf_rcu_read_unlock(void) __ksym; @@ -37,23 +41,50 @@ int cgroup_iter(struct bpf_iter__cgroup *ctx) return 0; } +static void __no_rcu_lock(struct cgroup *cgrp) +{ + long *ptr; + + /* Note that trace rcu is held in sleepable prog, so we can use + * bpf_cgrp_storage_get() in sleepable prog. + */ + ptr = bpf_cgrp_storage_get(&map_a, cgrp, 0, + BPF_LOCAL_STORAGE_GET_F_CREATE); + if (ptr) + cgroup_id = cgrp->kn->id; +} + +SEC("?fentry.s/" SYS_PREFIX "sys_getpgid") +int cgrp1_no_rcu_lock(void *ctx) +{ + struct task_struct *task; + struct cgroup *cgrp; + + task = bpf_get_current_task_btf(); + if (task->pid != target_pid) + return 0; + + /* bpf_task_get_cgroup1 can work in sleepable prog */ + cgrp = bpf_task_get_cgroup1(task, target_hid); + if (!cgrp) + return 0; + + __no_rcu_lock(cgrp); + bpf_cgroup_release(cgrp); + return 0; +} + SEC("?fentry.s/" SYS_PREFIX "sys_getpgid") int no_rcu_lock(void *ctx) { struct task_struct *task; - struct cgroup *cgrp; - long *ptr; task = bpf_get_current_task_btf(); if (task->pid != target_pid) return 0; /* task->cgroups is untrusted in sleepable prog outside of RCU CS */ - cgrp = task->cgroups->dfl_cgrp; - ptr = bpf_cgrp_storage_get(&map_a, cgrp, 0, - BPF_LOCAL_STORAGE_GET_F_CREATE); - if (ptr) - cgroup_id = cgrp->kn->id; + __no_rcu_lock(task->cgroups->dfl_cgrp); return 0; } @@ -68,6 +99,22 @@ int yes_rcu_lock(void *ctx) if (task->pid != target_pid) return 0; + if (is_cgroup1) { + bpf_rcu_read_lock(); + cgrp = bpf_task_get_cgroup1(task, target_hid); + if (!cgrp) { + bpf_rcu_read_unlock(); + return 0; + } + + ptr = bpf_cgrp_storage_get(&map_a, cgrp, 0, BPF_LOCAL_STORAGE_GET_F_CREATE); + if (ptr) + cgroup_id = cgrp->kn->id; + bpf_cgroup_release(cgrp); + bpf_rcu_read_unlock(); + return 0; + } + bpf_rcu_read_lock(); cgrp = task->cgroups->dfl_cgrp; /* cgrp is trusted under RCU CS */ diff --git a/tools/testing/selftests/bpf/progs/cgrp_ls_tp_btf.c b/tools/testing/selftests/bpf/progs/cgrp_ls_tp_btf.c index 9ebb8e2fe541..1c348f000f38 100644 --- a/tools/testing/selftests/bpf/progs/cgrp_ls_tp_btf.c +++ b/tools/testing/selftests/bpf/progs/cgrp_ls_tp_btf.c @@ -27,62 +27,100 @@ pid_t target_pid = 0; int mismatch_cnt = 0; int enter_cnt = 0; int exit_cnt = 0; +int target_hid = 0; +bool is_cgroup1 = 0; + +struct cgroup *bpf_task_get_cgroup1(struct task_struct *task, int hierarchy_id) __ksym; +void bpf_cgroup_release(struct cgroup *cgrp) __ksym; + +static void __on_enter(struct pt_regs *regs, long id, struct cgroup *cgrp) +{ + long *ptr; + int err; + + /* populate value 0 */ + ptr = bpf_cgrp_storage_get(&map_a, cgrp, 0, + BPF_LOCAL_STORAGE_GET_F_CREATE); + if (!ptr) + return; + + /* delete value 0 */ + err = bpf_cgrp_storage_delete(&map_a, cgrp); + if (err) + return; + + /* value is not available */ + ptr = bpf_cgrp_storage_get(&map_a, cgrp, 0, 0); + if (ptr) + return; + + /* re-populate the value */ + ptr = bpf_cgrp_storage_get(&map_a, cgrp, 0, + BPF_LOCAL_STORAGE_GET_F_CREATE); + if (!ptr) + return; + __sync_fetch_and_add(&enter_cnt, 1); + *ptr = MAGIC_VALUE + enter_cnt; +} SEC("tp_btf/sys_enter") int BPF_PROG(on_enter, struct pt_regs *regs, long id) { struct task_struct *task; - long *ptr; - int err; + struct cgroup *cgrp; task = bpf_get_current_task_btf(); if (task->pid != target_pid) return 0; - /* populate value 0 */ - ptr = bpf_cgrp_storage_get(&map_a, task->cgroups->dfl_cgrp, 0, - BPF_LOCAL_STORAGE_GET_F_CREATE); - if (!ptr) - return 0; + if (is_cgroup1) { + cgrp = bpf_task_get_cgroup1(task, target_hid); + if (!cgrp) + return 0; - /* delete value 0 */ - err = bpf_cgrp_storage_delete(&map_a, task->cgroups->dfl_cgrp); - if (err) + __on_enter(regs, id, cgrp); + bpf_cgroup_release(cgrp); return 0; + } - /* value is not available */ - ptr = bpf_cgrp_storage_get(&map_a, task->cgroups->dfl_cgrp, 0, 0); - if (ptr) - return 0; - - /* re-populate the value */ - ptr = bpf_cgrp_storage_get(&map_a, task->cgroups->dfl_cgrp, 0, - BPF_LOCAL_STORAGE_GET_F_CREATE); - if (!ptr) - return 0; - __sync_fetch_and_add(&enter_cnt, 1); - *ptr = MAGIC_VALUE + enter_cnt; - + __on_enter(regs, id, task->cgroups->dfl_cgrp); return 0; } +static void __on_exit(struct pt_regs *regs, long id, struct cgroup *cgrp) +{ + long *ptr; + + ptr = bpf_cgrp_storage_get(&map_a, cgrp, 0, + BPF_LOCAL_STORAGE_GET_F_CREATE); + if (!ptr) + return; + + __sync_fetch_and_add(&exit_cnt, 1); + if (*ptr != MAGIC_VALUE + exit_cnt) + __sync_fetch_and_add(&mismatch_cnt, 1); +} + SEC("tp_btf/sys_exit") int BPF_PROG(on_exit, struct pt_regs *regs, long id) { struct task_struct *task; - long *ptr; + struct cgroup *cgrp; task = bpf_get_current_task_btf(); if (task->pid != target_pid) return 0; - ptr = bpf_cgrp_storage_get(&map_a, task->cgroups->dfl_cgrp, 0, - BPF_LOCAL_STORAGE_GET_F_CREATE); - if (!ptr) - return 0; + if (is_cgroup1) { + cgrp = bpf_task_get_cgroup1(task, target_hid); + if (!cgrp) + return 0; - __sync_fetch_and_add(&exit_cnt, 1); - if (*ptr != MAGIC_VALUE + exit_cnt) - __sync_fetch_and_add(&mismatch_cnt, 1); + __on_exit(regs, id, cgrp); + bpf_cgroup_release(cgrp); + return 0; + } + + __on_exit(regs, id, task->cgroups->dfl_cgrp); return 0; }