Re: [PATCH bpf-next v2 4/8] bpf: Introduce cgroup iter

kernel test robot
2022-06-11T12:55:37Z

Hi Yosry,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on bpf-next/master]

url: https://github.com/intel-lab-lkp/linux/commits/Yosry-Ahmed/bpf-rstat-cgroup-hierarchical-stats/20220611-034720
base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
config: m68k-randconfig-r004-20220611 (https://download.01.org/0day-ci/archive/20220611/202206112000.LRgcxlpN-lkp-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org/config)
compiler: m68k-linux-gcc (GCC) 11.3.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/619857fd1ec4f351376ffcaaec20acc9aae9486f
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Yosry-Ahmed/bpf-rstat-cgroup-hierarchical-stats/20220611-034720
git checkout 619857fd1ec4f351376ffcaaec20acc9aae9486f
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.3.0 make.cross W=1 O=build_dir ARCH=m68k SHELL=/bin/bash kernel/bpf/ kernel/cgroup/

If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>

All error/warnings (new ones prefixed by >>):

In file included from kernel/bpf/cgroup_iter.c:9:
>> kernel/bpf/../cgroup/cgroup-internal.h:78:41: error: field 'iter' has incomplete type
78 | struct css_task_iter iter;
| ^~~~
kernel/bpf/../cgroup/cgroup-internal.h: In function 'cgroup_is_dead':
>> kernel/bpf/../cgroup/cgroup-internal.h:188:22: error: invalid use of undefined type 'const struct cgroup'
188 | return !(cgrp->self.flags & CSS_ONLINE);
| ^~
>> kernel/bpf/../cgroup/cgroup-internal.h:188:37: error: 'CSS_ONLINE' undeclared (first use in this function); did you mean 'N_ONLINE'?
188 | return !(cgrp->self.flags & CSS_ONLINE);
| ^~~~~~~~~~
| N_ONLINE
kernel/bpf/../cgroup/cgroup-internal.h:188:37: note: each undeclared identifier is reported only once for each function it appears in
kernel/bpf/../cgroup/cgroup-internal.h: In function 'notify_on_release':
>> kernel/bpf/../cgroup/cgroup-internal.h:193:25: error: 'CGRP_NOTIFY_ON_RELEASE' undeclared (first use in this function)
193 | return test_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags);
| ^~~~~~~~~~~~~~~~~~~~~~
kernel/bpf/../cgroup/cgroup-internal.h:193:54: error: invalid use of undefined type 'const struct cgroup'
193 | return test_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags);
| ^~
kernel/bpf/../cgroup/cgroup-internal.h: In function 'put_css_set':
>> kernel/bpf/../cgroup/cgroup-internal.h:207:39: error: invalid use of undefined type 'struct css_set'
207 | if (refcount_dec_not_one(&cset->refcount))
| ^~
kernel/bpf/../cgroup/cgroup-internal.h: In function 'get_css_set':
kernel/bpf/../cgroup/cgroup-internal.h:220:27: error: invalid use of undefined type 'struct css_set'
220 | refcount_inc(&cset->refcount);
| ^~
kernel/bpf/../cgroup/cgroup-internal.h: At top level:
>> kernel/bpf/../cgroup/cgroup-internal.h:284:22: error: array type has incomplete element type 'struct cftype'
284 | extern struct cftype cgroup1_base_files[];
| ^~~~~~~~~~~~~~~~~~
kernel/bpf/cgroup_iter.c: In function 'cgroup_iter_seq_start':
>> kernel/bpf/cgroup_iter.c:55:24: error: implicit declaration of function 'css_next_descendant_pre' [-Werror=implicit-function-declaration]
55 | return css_next_descendant_pre(NULL, p->start_css);
| ^~~~~~~~~~~~~~~~~~~~~~~
>> kernel/bpf/cgroup_iter.c:55:24: warning: returning 'int' from a function with return type 'void *' makes pointer from integer without a cast [-Wint-conversion]
55 | return css_next_descendant_pre(NULL, p->start_css);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> kernel/bpf/cgroup_iter.c:57:24: error: implicit declaration of function 'css_next_descendant_post' [-Werror=implicit-function-declaration]
57 | return css_next_descendant_post(NULL, p->start_css);
| ^~~~~~~~~~~~~~~~~~~~~~~~
kernel/bpf/cgroup_iter.c:57:24: warning: returning 'int' from a function with return type 'void *' makes pointer from integer without a cast [-Wint-conversion]
57 | return css_next_descendant_post(NULL, p->start_css);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
kernel/bpf/cgroup_iter.c: In function 'cgroup_iter_seq_next':
kernel/bpf/cgroup_iter.c:83:24: warning: returning 'int' from a function with return type 'void *' makes pointer from integer without a cast [-Wint-conversion]
83 | return css_next_descendant_pre(curr, p->start_css);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
kernel/bpf/cgroup_iter.c:85:24: warning: returning 'int' from a function with return type 'void *' makes pointer from integer without a cast [-Wint-conversion]
85 | return css_next_descendant_post(curr, p->start_css);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> kernel/bpf/cgroup_iter.c:87:28: error: invalid use of undefined type 'struct cgroup_subsys_state'
87 | return curr->parent;
| ^~
kernel/bpf/cgroup_iter.c: In function '__cgroup_iter_seq_show':
kernel/bpf/cgroup_iter.c:100:38: error: invalid use of undefined type 'struct cgroup_subsys_state'
100 | if (css && cgroup_is_dead(css->cgroup))
| ^~
kernel/bpf/cgroup_iter.c:104:31: error: invalid use of undefined type 'struct cgroup_subsys_state'
104 | ctx.cgroup = css ? css->cgroup : NULL;
| ^~
kernel/bpf/cgroup_iter.c: In function 'cgroup_iter_seq_init':
>> kernel/bpf/cgroup_iter.c:137:29: error: invalid use of undefined type 'struct cgroup'
137 | p->start_css = &cgrp->self;
| ^~
kernel/bpf/cgroup_iter.c: In function 'bpf_iter_attach_cgroup':
>> kernel/bpf/cgroup_iter.c:157:24: error: implicit declaration of function 'cgroup_get_from_fd'; did you mean 'cgroup_get_from_id'? [-Werror=implicit-function-declaration]
157 | cgrp = cgroup_get_from_fd(fd);
| ^~~~~~~~~~~~~~~~~~
| cgroup_get_from_id
>> kernel/bpf/cgroup_iter.c:157:22: warning: assignment to 'struct cgroup *' from 'int' makes pointer from integer without a cast [-Wint-conversion]
157 | cgrp = cgroup_get_from_fd(fd);
| ^
>> kernel/bpf/cgroup_iter.c:159:24: error: implicit declaration of function 'cgroup_get_from_path'; did you mean 'cgroup_get_from_id'? [-Werror=implicit-function-declaration]
159 | cgrp = cgroup_get_from_path("/");
| ^~~~~~~~~~~~~~~~~~~~
| cgroup_get_from_id
kernel/bpf/cgroup_iter.c:159:22: warning: assignment to 'struct cgroup *' from 'int' makes pointer from integer without a cast [-Wint-conversion]
159 | cgrp = cgroup_get_from_path("/");
| ^
kernel/bpf/cgroup_iter.c: In function 'bpf_iter_cgroup_show_fdinfo':
>> kernel/bpf/cgroup_iter.c:190:9: error: implicit declaration of function 'cgroup_path_ns'; did you mean 'cgroup_parent'? [-Werror=implicit-function-declaration]
190 | cgroup_path_ns(aux->cgroup.start, buf, PATH_MAX,
| ^~~~~~~~~~~~~~
| cgroup_parent
kernel/bpf/cgroup_iter.c: In function 'cgroup_iter_seq_next':
kernel/bpf/cgroup_iter.c:88:1: error: control reaches end of non-void function [-Werror=return-type]
88 | }
| ^
cc1: some warnings being treated as errors

vim +/iter +78 kernel/bpf/../cgroup/cgroup-internal.h

0d2b5955b36250 Tejun Heo 2022-01-06 68
0d2b5955b36250 Tejun Heo 2022-01-06 69 struct cgroup_file_ctx {
e57457641613fe Tejun Heo 2022-01-06 70 struct cgroup_namespace *ns;
e57457641613fe Tejun Heo 2022-01-06 71
0d2b5955b36250 Tejun Heo 2022-01-06 72 struct {
0d2b5955b36250 Tejun Heo 2022-01-06 73 void *trigger;
0d2b5955b36250 Tejun Heo 2022-01-06 74 } psi;
0d2b5955b36250 Tejun Heo 2022-01-06 75
0d2b5955b36250 Tejun Heo 2022-01-06 76 struct {
0d2b5955b36250 Tejun Heo 2022-01-06 77 bool started;
0d2b5955b36250 Tejun Heo 2022-01-06 @78 struct css_task_iter iter;
0d2b5955b36250 Tejun Heo 2022-01-06 79 } procs;
0d2b5955b36250 Tejun Heo 2022-01-06 80
0d2b5955b36250 Tejun Heo 2022-01-06 81 struct {
0d2b5955b36250 Tejun Heo 2022-01-06 82 struct cgroup_pidlist *pidlist;
0d2b5955b36250 Tejun Heo 2022-01-06 83 } procs1;
0d2b5955b36250 Tejun Heo 2022-01-06 84 };
0d2b5955b36250 Tejun Heo 2022-01-06 85
0a268dbd7932c7 Tejun Heo 2016-12-27 86 /*
0a268dbd7932c7 Tejun Heo 2016-12-27 87 * A cgroup can be associated with multiple css_sets as different tasks may
0a268dbd7932c7 Tejun Heo 2016-12-27 88 * belong to different cgroups on different hierarchies. In the other
0a268dbd7932c7 Tejun Heo 2016-12-27 89 * direction, a css_set is naturally associated with multiple cgroups.
0a268dbd7932c7 Tejun Heo 2016-12-27 90 * This M:N relationship is represented by the following link structure
0a268dbd7932c7 Tejun Heo 2016-12-27 91 * which exists for each association and allows traversing the associations
0a268dbd7932c7 Tejun Heo 2016-12-27 92 * from both sides.
0a268dbd7932c7 Tejun Heo 2016-12-27 93 */
0a268dbd7932c7 Tejun Heo 2016-12-27 94 struct cgrp_cset_link {
0a268dbd7932c7 Tejun Heo 2016-12-27 95 /* the cgroup and css_set this link associates */
0a268dbd7932c7 Tejun Heo 2016-12-27 96 struct cgroup *cgrp;
0a268dbd7932c7 Tejun Heo 2016-12-27 97 struct css_set *cset;
0a268dbd7932c7 Tejun Heo 2016-12-27 98
0a268dbd7932c7 Tejun Heo 2016-12-27 99 /* list of cgrp_cset_links anchored at cgrp->cset_links */
0a268dbd7932c7 Tejun Heo 2016-12-27 100 struct list_head cset_link;
0a268dbd7932c7 Tejun Heo 2016-12-27 101
0a268dbd7932c7 Tejun Heo 2016-12-27 102 /* list of cgrp_cset_links anchored at css_set->cgrp_links */
0a268dbd7932c7 Tejun Heo 2016-12-27 103 struct list_head cgrp_link;
0a268dbd7932c7 Tejun Heo 2016-12-27 104 };
0a268dbd7932c7 Tejun Heo 2016-12-27 105
e595cd706982bf Tejun Heo 2017-01-15 106 /* used to track tasks and csets during migration */
e595cd706982bf Tejun Heo 2017-01-15 107 struct cgroup_taskset {
e595cd706982bf Tejun Heo 2017-01-15 108 /* the src and dst cset list running through cset->mg_node */
e595cd706982bf Tejun Heo 2017-01-15 109 struct list_head src_csets;
e595cd706982bf Tejun Heo 2017-01-15 110 struct list_head dst_csets;
e595cd706982bf Tejun Heo 2017-01-15 111
610467270fb368 Tejun Heo 2017-07-08 112 /* the number of tasks in the set */
610467270fb368 Tejun Heo 2017-07-08 113 int nr_tasks;
610467270fb368 Tejun Heo 2017-07-08 114
e595cd706982bf Tejun Heo 2017-01-15 115 /* the subsys currently being processed */
e595cd706982bf Tejun Heo 2017-01-15 116 int ssid;
e595cd706982bf Tejun Heo 2017-01-15 117
e595cd706982bf Tejun Heo 2017-01-15 118 /*
e595cd706982bf Tejun Heo 2017-01-15 119 * Fields for cgroup_taskset_*() iteration.
e595cd706982bf Tejun Heo 2017-01-15 120 *
e595cd706982bf Tejun Heo 2017-01-15 121 * Before migration is committed, the target migration tasks are on
e595cd706982bf Tejun Heo 2017-01-15 122 * ->mg_tasks of the csets on ->src_csets. After, on ->mg_tasks of
e595cd706982bf Tejun Heo 2017-01-15 123 * the csets on ->dst_csets. ->csets point to either ->src_csets
e595cd706982bf Tejun Heo 2017-01-15 124 * or ->dst_csets depending on whether migration is committed.
e595cd706982bf Tejun Heo 2017-01-15 125 *
e595cd706982bf Tejun Heo 2017-01-15 126 * ->cur_csets and ->cur_task point to the current task position
e595cd706982bf Tejun Heo 2017-01-15 127 * during iteration.
e595cd706982bf Tejun Heo 2017-01-15 128 */
e595cd706982bf Tejun Heo 2017-01-15 129 struct list_head *csets;
e595cd706982bf Tejun Heo 2017-01-15 130 struct css_set *cur_cset;
e595cd706982bf Tejun Heo 2017-01-15 131 struct task_struct *cur_task;
e595cd706982bf Tejun Heo 2017-01-15 132 };
e595cd706982bf Tejun Heo 2017-01-15 133
e595cd706982bf Tejun Heo 2017-01-15 134 /* migration context also tracks preloading */
e595cd706982bf Tejun Heo 2017-01-15 135 struct cgroup_mgctx {
e595cd706982bf Tejun Heo 2017-01-15 136 /*
e595cd706982bf Tejun Heo 2017-01-15 137 * Preloaded source and destination csets. Used to guarantee
e595cd706982bf Tejun Heo 2017-01-15 138 * atomic success or failure on actual migration.
e595cd706982bf Tejun Heo 2017-01-15 139 */
e595cd706982bf Tejun Heo 2017-01-15 140 struct list_head preloaded_src_csets;
e595cd706982bf Tejun Heo 2017-01-15 141 struct list_head preloaded_dst_csets;
e595cd706982bf Tejun Heo 2017-01-15 142
e595cd706982bf Tejun Heo 2017-01-15 143 /* tasks and csets to migrate */
e595cd706982bf Tejun Heo 2017-01-15 144 struct cgroup_taskset tset;
bfc2cf6f61fcea Tejun Heo 2017-01-15 145
bfc2cf6f61fcea Tejun Heo 2017-01-15 146 /* subsystems affected by migration */
bfc2cf6f61fcea Tejun Heo 2017-01-15 147 u16 ss_mask;
e595cd706982bf Tejun Heo 2017-01-15 148 };
e595cd706982bf Tejun Heo 2017-01-15 149
e595cd706982bf Tejun Heo 2017-01-15 150 #define CGROUP_TASKSET_INIT(tset) \
e595cd706982bf Tejun Heo 2017-01-15 151 { \
e595cd706982bf Tejun Heo 2017-01-15 152 .src_csets = LIST_HEAD_INIT(tset.src_csets), \
e595cd706982bf Tejun Heo 2017-01-15 153 .dst_csets = LIST_HEAD_INIT(tset.dst_csets), \
e595cd706982bf Tejun Heo 2017-01-15 154 .csets = &tset.src_csets, \
e595cd706982bf Tejun Heo 2017-01-15 155 }
e595cd706982bf Tejun Heo 2017-01-15 156
e595cd706982bf Tejun Heo 2017-01-15 157 #define CGROUP_MGCTX_INIT(name) \
e595cd706982bf Tejun Heo 2017-01-15 158 { \
e595cd706982bf Tejun Heo 2017-01-15 159 LIST_HEAD_INIT(name.preloaded_src_csets), \
e595cd706982bf Tejun Heo 2017-01-15 160 LIST_HEAD_INIT(name.preloaded_dst_csets), \
e595cd706982bf Tejun Heo 2017-01-15 161 CGROUP_TASKSET_INIT(name.tset), \
e595cd706982bf Tejun Heo 2017-01-15 162 }
e595cd706982bf Tejun Heo 2017-01-15 163
e595cd706982bf Tejun Heo 2017-01-15 164 #define DEFINE_CGROUP_MGCTX(name) \
e595cd706982bf Tejun Heo 2017-01-15 165 struct cgroup_mgctx name = CGROUP_MGCTX_INIT(name)
e595cd706982bf Tejun Heo 2017-01-15 166
0a268dbd7932c7 Tejun Heo 2016-12-27 167 extern struct mutex cgroup_mutex;
0a268dbd7932c7 Tejun Heo 2016-12-27 168 extern spinlock_t css_set_lock;
0a268dbd7932c7 Tejun Heo 2016-12-27 169 extern struct cgroup_subsys *cgroup_subsys[];
0a268dbd7932c7 Tejun Heo 2016-12-27 170 extern struct list_head cgroup_roots;
0a268dbd7932c7 Tejun Heo 2016-12-27 171 extern struct file_system_type cgroup_fs_type;
0a268dbd7932c7 Tejun Heo 2016-12-27 172
0a268dbd7932c7 Tejun Heo 2016-12-27 173 /* iterate across the hierarchies */
0a268dbd7932c7 Tejun Heo 2016-12-27 174 #define for_each_root(root) \
0a268dbd7932c7 Tejun Heo 2016-12-27 175 list_for_each_entry((root), &cgroup_roots, root_list)
0a268dbd7932c7 Tejun Heo 2016-12-27 176
0a268dbd7932c7 Tejun Heo 2016-12-27 177 /**
0a268dbd7932c7 Tejun Heo 2016-12-27 178 * for_each_subsys - iterate all enabled cgroup subsystems
0a268dbd7932c7 Tejun Heo 2016-12-27 179 * @ss: the iteration cursor
0a268dbd7932c7 Tejun Heo 2016-12-27 180 * @ssid: the index of @ss, CGROUP_SUBSYS_COUNT after reaching the end
0a268dbd7932c7 Tejun Heo 2016-12-27 181 */
0a268dbd7932c7 Tejun Heo 2016-12-27 182 #define for_each_subsys(ss, ssid) \
0a268dbd7932c7 Tejun Heo 2016-12-27 183 for ((ssid) = 0; (ssid) < CGROUP_SUBSYS_COUNT && \
0a268dbd7932c7 Tejun Heo 2016-12-27 184 (((ss) = cgroup_subsys[ssid]) || true); (ssid)++)
0a268dbd7932c7 Tejun Heo 2016-12-27 185
0a268dbd7932c7 Tejun Heo 2016-12-27 186 static inline bool cgroup_is_dead(const struct cgroup *cgrp)
0a268dbd7932c7 Tejun Heo 2016-12-27 187 {
0a268dbd7932c7 Tejun Heo 2016-12-27 @188 return !(cgrp->self.flags & CSS_ONLINE);
0a268dbd7932c7 Tejun Heo 2016-12-27 189 }
0a268dbd7932c7 Tejun Heo 2016-12-27 190
0a268dbd7932c7 Tejun Heo 2016-12-27 191 static inline bool notify_on_release(const struct cgroup *cgrp)
0a268dbd7932c7 Tejun Heo 2016-12-27 192 {
0a268dbd7932c7 Tejun Heo 2016-12-27 @193 return test_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags);
0a268dbd7932c7 Tejun Heo 2016-12-27 194 }
0a268dbd7932c7 Tejun Heo 2016-12-27 195
dcfe149b9f45aa Tejun Heo 2016-12-27 196 void put_css_set_locked(struct css_set *cset);
dcfe149b9f45aa Tejun Heo 2016-12-27 197
dcfe149b9f45aa Tejun Heo 2016-12-27 198 static inline void put_css_set(struct css_set *cset)
dcfe149b9f45aa Tejun Heo 2016-12-27 199 {
dcfe149b9f45aa Tejun Heo 2016-12-27 200 unsigned long flags;
dcfe149b9f45aa Tejun Heo 2016-12-27 201
dcfe149b9f45aa Tejun Heo 2016-12-27 202 /*
dcfe149b9f45aa Tejun Heo 2016-12-27 203 * Ensure that the refcount doesn't hit zero while any readers
dcfe149b9f45aa Tejun Heo 2016-12-27 204 * can see it. Similar to atomic_dec_and_lock(), but for an
dcfe149b9f45aa Tejun Heo 2016-12-27 205 * rwlock
dcfe149b9f45aa Tejun Heo 2016-12-27 206 */
4b9502e63b5e2b Elena Reshetova 2017-03-08 @207 if (refcount_dec_not_one(&cset->refcount))
dcfe149b9f45aa Tejun Heo 2016-12-27 208 return;
dcfe149b9f45aa Tejun Heo 2016-12-27 209
dcfe149b9f45aa Tejun Heo 2016-12-27 210 spin_lock_irqsave(&css_set_lock, flags);
dcfe149b9f45aa Tejun Heo 2016-12-27 211 put_css_set_locked(cset);
dcfe149b9f45aa Tejun Heo 2016-12-27 212 spin_unlock_irqrestore(&css_set_lock, flags);
dcfe149b9f45aa Tejun Heo 2016-12-27 213 }
dcfe149b9f45aa Tejun Heo 2016-12-27 214

--
0-DAY CI Kernel Test Service