tree: https://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup.git review-cgroup2-threads-v3 head: 6fb1273ffe28c2f094c7816768854a74312bf1ed commit: 6fb1273ffe28c2f094c7816768854a74312bf1ed [10/10] cgroup: update debug controller to print out thread mode information reproduce: # apt-get install sparse git checkout 6fb1273ffe28c2f094c7816768854a74312bf1ed make ARCH=x86_64 allmodconfig make C=1 CF=-D__CHECK_ENDIAN__ sparse warnings: (new ones prefixed by >>) include/linux/compiler.h:260:8: sparse: attribute 'no_sanitize_address': unknown attribute >> kernel/cgroup/debug.c:137:21: sparse: incompatible types in comparison expression (different address spaces) vim +137 kernel/cgroup/debug.c 111 112 #define MAX_TASKS_SHOWN_PER_CSS 25 113 static int cgroup_css_links_read(struct seq_file *seq, void *v) 114 { 115 struct cgroup_subsys_state *css = seq_css(seq); 116 struct cgrp_cset_link *link; 117 int dead_cnt = 0, extra_refs = 0, threaded_csets = 0; 118 119 spin_lock_irq(&css_set_lock); 120 121 if (cgroup_is_thread_root(css->cgroup)) 122 seq_puts(seq, "[thread root]\n"); 123 else if (cgroup_is_threaded(css->cgroup)) 124 seq_puts(seq, "[threaded]\n"); 125 126 list_for_each_entry(link, &css->cgroup->cset_links, cset_link) { 127 struct css_set *cset = link->cset; 128 struct task_struct *task; 129 int count = 0; 130 int refcnt = refcount_read(&cset->refcount); 131 132 /* 133 * Print out the proc_cset and threaded_cset relationship 134 * and highlight difference between refcount and task_count. 135 */ 136 seq_printf(seq, "css_set %pK", cset); > 137 if (rcu_dereference_protected(cset->dom_cset, 1) != cset) { 138 threaded_csets++; 139 seq_printf(seq, "=>%pK", cset->dom_cset); 140 } 141 if (!list_empty(&cset->threaded_csets)) { 142 struct css_set *tcset; 143 int idx = 0; 144 145 list_for_each_entry(tcset, &cset->threaded_csets, 146 threaded_csets_node) { 147 seq_puts(seq, idx ? "," : "<="); 148 seq_printf(seq, "%pK", tcset); 149 idx++; 150 } 151 } else { 152 seq_printf(seq, " %d", refcnt); 153 if (refcnt - cset->nr_tasks > 0) { 154 int extra = refcnt - cset->nr_tasks; 155 156 seq_printf(seq, " +%d", extra); 157 /* 158 * Take out the one additional reference in 159 * init_css_set. 160 */ 161 if (cset == &init_css_set) 162 extra--; 163 extra_refs += extra; 164 } 165 } 166 seq_puts(seq, "\n"); 167 168 list_for_each_entry(task, &cset->tasks, cg_list) { 169 if (count++ <= MAX_TASKS_SHOWN_PER_CSS) 170 seq_printf(seq, " task %d\n", 171 task_pid_vnr(task)); 172 } 173 174 list_for_each_entry(task, &cset->mg_tasks, cg_list) { 175 if (count++ <= MAX_TASKS_SHOWN_PER_CSS) 176 seq_printf(seq, " task %d\n", 177 task_pid_vnr(task)); 178 } 179 /* show # of overflowed tasks */ 180 if (count > MAX_TASKS_SHOWN_PER_CSS) 181 seq_printf(seq, " ... (%d)\n", 182 count - MAX_TASKS_SHOWN_PER_CSS); 183 184 if (cset->dead) { 185 seq_puts(seq, " [dead]\n"); 186 dead_cnt++; 187 } 188 189 WARN_ON(count != cset->nr_tasks); 190 } 191 spin_unlock_irq(&css_set_lock); 192 193 if (!dead_cnt && !extra_refs && !threaded_csets) 194 return 0; 195 196 seq_puts(seq, "\n"); 197 if (threaded_csets) 198 seq_printf(seq, "threaded css_sets = %d\n", threaded_csets); 199 if (extra_refs) 200 seq_printf(seq, "extra references = %d\n", extra_refs); 201 if (dead_cnt) 202 seq_printf(seq, "dead css_sets = %d\n", dead_cnt); 203 204 return 0; 205 } 206 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation -- To unsubscribe from this list: send the line "unsubscribe cgroups" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
