/* * debugfs file to track time spent in suspend * * Copyright (c) 2011, Google, Inc. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. */ #include #include #include #include #include #include #include "timekeeping_internal.h" #define NUM_BINS 32 static unsigned int sleep_time_bin[NUM_BINS] = {0}; static int tk_debug_show_sleep_time(struct seq_file *s, void *data) { unsigned int bin; seq_puts(s, " time (secs) count\n"); seq_puts(s, "------------------------------\n"); for (bin = 0; bin < 32; bin++) { if (sleep_time_bin[bin] == 0) continue; seq_printf(s, "%10u - %-10u %4u\n", bin ? 1 << (bin - 1) : 0, 1 << bin, sleep_time_bin[bin]); } return 0; } static int tk_debug_sleep_time_open(struct inode *inode, struct file *file) { return single_open(file, tk_debug_show_sleep_time, NULL); } static const struct file_operations tk_debug_sleep_time_fops = { .open = tk_debug_sleep_time_open, .read = seq_read, .llseek = seq_lseek, .release = single_release, }; static int __init tk_debug_sleep_time_init(void) { struct dentry *d; d = debugfs_create_file("sleep_time", 0444, NULL, NULL, &tk_debug_sleep_time_fops); if (!d) { pr_err("Failed to create sleep_time debug file\n"); return -ENOMEM; } return 0; } late_initcall(tk_debug_sleep_time_init); void tk_debug_account_sleep_time(struct timespec64 *t) { /* Cap bin index so we don't overflow the array */ int bin = min(fls(t->tv_sec), NUM_BINS-1); sleep_time_bin[bin]++; pr_info("Suspended for %lld.%03lu seconds\n", (s64)t->tv_sec, t->tv_nsec / NSEC_PER_MSEC); } mitdiff
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authorTejun Heo <tj@kernel.org>2017-01-26 16:47:28 -0500
committerTejun Heo <tj@kernel.org>2017-01-26 16:47:28 -0500
commit07cd12945551b63ecb1a349d50a6d69d1d6feb4a (patch)
tree75f65eba7eac9277971082a2d5a4cf1370562c0c /include/xen/xenbus.h
parent7ce7d89f48834cefece7804d38fc5d85382edf77 (diff)
cgroup: don't online subsystems before cgroup_name/path() are operational
While refactoring cgroup creation, a5bca2152036 ("cgroup: factor out cgroup_create() out of cgroup_mkdir()") incorrectly onlined subsystems before the new cgroup is associated with it kernfs_node. This is fine for cgroup proper but cgroup_name/path() depend on the associated kernfs_node and if a subsystem makes the new cgroup_subsys_state visible, which they're allowed to after onlining, it can lead to NULL dereference. The current code performs cgroup creation and subsystem onlining in cgroup_create() and cgroup_mkdir() makes the cgroup and subsystems visible afterwards. There's no reason to online the subsystems early and we can simply drop cgroup_apply_control_enable() call from cgroup_create() so that the subsystems are onlined and made visible at the same time. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Fixes: a5bca2152036 ("cgroup: factor out cgroup_create() out of cgroup_mkdir()") Cc: stable@vger.kernel.org # v4.6+
Diffstat (limited to 'include/xen/xenbus.h')