diff options
-rw-r--r-- | drivers/staging/android/binder.c | 5 | ||||
-rw-r--r-- | fs/cifs/transport.c | 2 | ||||
-rw-r--r-- | fs/eventpoll.c | 4 | ||||
-rw-r--r-- | fs/nfs/inode.c | 2 | ||||
-rw-r--r-- | fs/nfs/nfs3proc.c | 2 | ||||
-rw-r--r-- | fs/nfs/nfs4proc.c | 4 | ||||
-rw-r--r-- | fs/select.c | 4 | ||||
-rw-r--r-- | include/linux/debug_locks.h | 4 | ||||
-rw-r--r-- | include/linux/freezer.h | 171 | ||||
-rw-r--r-- | kernel/exit.c | 2 | ||||
-rw-r--r-- | kernel/freezer.c | 12 | ||||
-rw-r--r-- | kernel/futex.c | 3 | ||||
-rw-r--r-- | kernel/hrtimer.c | 3 | ||||
-rw-r--r-- | kernel/lockdep.c | 17 | ||||
-rw-r--r-- | kernel/power/process.c | 26 | ||||
-rw-r--r-- | kernel/signal.c | 2 | ||||
-rw-r--r-- | net/sunrpc/sched.c | 2 | ||||
-rw-r--r-- | net/unix/af_unix.c | 3 |
18 files changed, 200 insertions, 68 deletions
diff --git a/drivers/staging/android/binder.c b/drivers/staging/android/binder.c index 1567ac2..1ffc2eb 100644 --- a/drivers/staging/android/binder.c +++ b/drivers/staging/android/binder.c @@ -20,6 +20,7 @@ #include <asm/cacheflush.h> #include <linux/fdtable.h> #include <linux/file.h> +#include <linux/freezer.h> #include <linux/fs.h> #include <linux/list.h> #include <linux/miscdevice.h> @@ -2140,13 +2141,13 @@ retry: if (!binder_has_proc_work(proc, thread)) ret = -EAGAIN; } else - ret = wait_event_interruptible_exclusive(proc->wait, binder_has_proc_work(proc, thread)); + ret = wait_event_freezable_exclusive(proc->wait, binder_has_proc_work(proc, thread)); } else { if (non_block) { if (!binder_has_thread_work(thread)) ret = -EAGAIN; } else - ret = wait_event_interruptible(thread->wait, binder_has_thread_work(thread)); + ret = wait_event_freezable(thread->wait, binder_has_thread_work(thread)); } binder_lock(__func__); diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c index bfbf470..b70aa7c 100644 --- a/fs/cifs/transport.c +++ b/fs/cifs/transport.c @@ -447,7 +447,7 @@ wait_for_response(struct TCP_Server_Info *server, struct mid_q_entry *midQ) { int error; - error = wait_event_freezekillable(server->response_q, + error = wait_event_freezekillable_unsafe(server->response_q, midQ->mid_state != MID_REQUEST_SUBMITTED); if (error < 0) return -ERESTARTSYS; diff --git a/fs/eventpoll.c b/fs/eventpoll.c index deecc72..0cff443 100644 --- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -34,6 +34,7 @@ #include <linux/mutex.h> #include <linux/anon_inodes.h> #include <linux/device.h> +#include <linux/freezer.h> #include <asm/uaccess.h> #include <asm/io.h> #include <asm/mman.h> @@ -1602,7 +1603,8 @@ fetch_events: } spin_unlock_irqrestore(&ep->lock, flags); - if (!schedule_hrtimeout_range(to, slack, HRTIMER_MODE_ABS)) + if (!freezable_schedule_hrtimeout_range(to, slack, + HRTIMER_MODE_ABS)) timed_out = 1; spin_lock_irqsave(&ep->lock, flags); diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c index c1c7a9d..ce72704 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -79,7 +79,7 @@ int nfs_wait_bit_killable(void *word) { if (fatal_signal_pending(current)) return -ERESTARTSYS; - freezable_schedule(); + freezable_schedule_unsafe(); return 0; } EXPORT_SYMBOL_GPL(nfs_wait_bit_killable); diff --git a/fs/nfs/nfs3proc.c b/fs/nfs/nfs3proc.c index 43ea96c..ce90eb4 100644 --- a/fs/nfs/nfs3proc.c +++ b/fs/nfs/nfs3proc.c @@ -33,7 +33,7 @@ nfs3_rpc_wrapper(struct rpc_clnt *clnt, struct rpc_message *msg, int flags) res = rpc_call_sync(clnt, msg, flags); if (res != -EJUKEBOX) break; - freezable_schedule_timeout_killable(NFS_JUKEBOX_RETRY_TIME); + freezable_schedule_timeout_killable_unsafe(NFS_JUKEBOX_RETRY_TIME); res = -ERESTARTSYS; } while (!fatal_signal_pending(current)); return res; diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index d7ba561..28241a4 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -268,7 +268,7 @@ static int nfs4_delay(struct rpc_clnt *clnt, long *timeout) *timeout = NFS4_POLL_RETRY_MIN; if (*timeout > NFS4_POLL_RETRY_MAX) *timeout = NFS4_POLL_RETRY_MAX; - freezable_schedule_timeout_killable(*timeout); + freezable_schedule_timeout_killable_unsafe(*timeout); if (fatal_signal_pending(current)) res = -ERESTARTSYS; *timeout <<= 1; @@ -4528,7 +4528,7 @@ int nfs4_proc_delegreturn(struct inode *inode, struct rpc_cred *cred, const nfs4 static unsigned long nfs4_set_lock_task_retry(unsigned long timeout) { - freezable_schedule_timeout_killable(timeout); + freezable_schedule_timeout_killable_unsafe(timeout); timeout <<= 1; if (timeout > NFS4_LOCK_MAXTIMEOUT) return NFS4_LOCK_MAXTIMEOUT; diff --git a/fs/select.c b/fs/select.c index 8c1c96c..6b14dc7 100644 --- a/fs/select.c +++ b/fs/select.c @@ -27,6 +27,7 @@ #include <linux/rcupdate.h> #include <linux/hrtimer.h> #include <linux/sched/rt.h> +#include <linux/freezer.h> #include <asm/uaccess.h> @@ -236,7 +237,8 @@ int poll_schedule_timeout(struct poll_wqueues *pwq, int state, set_current_state(state); if (!pwq->triggered) - rc = schedule_hrtimeout_range(expires, slack, HRTIMER_MODE_ABS); + rc = freezable_schedule_hrtimeout_range(expires, slack, + HRTIMER_MODE_ABS); __set_current_state(TASK_RUNNING); /* diff --git a/include/linux/debug_locks.h b/include/linux/debug_locks.h index 21ca773..822c135 100644 --- a/include/linux/debug_locks.h +++ b/include/linux/debug_locks.h @@ -51,7 +51,7 @@ struct task_struct; extern void debug_show_all_locks(void); extern void debug_show_held_locks(struct task_struct *task); extern void debug_check_no_locks_freed(const void *from, unsigned long len); -extern void debug_check_no_locks_held(struct task_struct *task); +extern void debug_check_no_locks_held(void); #else static inline void debug_show_all_locks(void) { @@ -67,7 +67,7 @@ debug_check_no_locks_freed(const void *from, unsigned long len) } static inline void -debug_check_no_locks_held(struct task_struct *task) +debug_check_no_locks_held(void) { } #endif diff --git a/include/linux/freezer.h b/include/linux/freezer.h index e70df40..7fd81b8 100644 --- a/include/linux/freezer.h +++ b/include/linux/freezer.h @@ -3,6 +3,7 @@ #ifndef FREEZER_H_INCLUDED #define FREEZER_H_INCLUDED +#include <linux/debug_locks.h> #include <linux/sched.h> #include <linux/wait.h> #include <linux/atomic.h> @@ -46,7 +47,11 @@ extern int freeze_kernel_threads(void); extern void thaw_processes(void); extern void thaw_kernel_threads(void); -static inline bool try_to_freeze(void) +/* + * DO NOT ADD ANY NEW CALLERS OF THIS FUNCTION + * If try_to_freeze causes a lockdep warning it means the caller may deadlock + */ +static inline bool try_to_freeze_unsafe(void) { might_sleep(); if (likely(!freezing(current))) @@ -54,6 +59,13 @@ static inline bool try_to_freeze(void) return __refrigerator(false); } +static inline bool try_to_freeze(void) +{ + if (!(current->flags & PF_NOFREEZE)) + debug_check_no_locks_held(); + return try_to_freeze_unsafe(); +} + extern bool freeze_task(struct task_struct *p); extern bool set_freezable(void); @@ -115,6 +127,14 @@ static inline void freezer_count(void) try_to_freeze(); } +/* DO NOT ADD ANY NEW CALLERS OF THIS FUNCTION */ +static inline void freezer_count_unsafe(void) +{ + current->flags &= ~PF_FREEZER_SKIP; + smp_mb(); + try_to_freeze_unsafe(); +} + /** * freezer_should_skip - whether to skip a task when determining frozen * state is reached @@ -139,28 +159,86 @@ static inline bool freezer_should_skip(struct task_struct *p) } /* - * These macros are intended to be used whenever you want allow a sleeping + * These functions are intended to be used whenever you want allow a sleeping * task to be frozen. Note that neither return any clear indication of * whether a freeze event happened while in this function. */ /* Like schedule(), but should not block the freezer. */ -#define freezable_schedule() \ -({ \ - freezer_do_not_count(); \ - schedule(); \ - freezer_count(); \ -}) +static inline void freezable_schedule(void) +{ + freezer_do_not_count(); + schedule(); + freezer_count(); +} + +/* DO NOT ADD ANY NEW CALLERS OF THIS FUNCTION */ +static inline void freezable_schedule_unsafe(void) +{ + freezer_do_not_count(); + schedule(); + freezer_count_unsafe(); +} + +/* + * Like freezable_schedule_timeout(), but should not block the freezer. Do not + * call this with locks held. + */ +static inline long freezable_schedule_timeout(long timeout) +{ + long __retval; + freezer_do_not_count(); + __retval = schedule_timeout(timeout); + freezer_count(); + return __retval; +} + +/* + * Like schedule_timeout_interruptible(), but should not block the freezer. Do not + * call this with locks held. + */ +static inline long freezable_schedule_timeout_interruptible(long timeout) +{ + long __retval; + freezer_do_not_count(); + __retval = schedule_timeout_interruptible(timeout); + freezer_count(); + return __retval; +} /* Like schedule_timeout_killable(), but should not block the freezer. */ -#define freezable_schedule_timeout_killable(timeout) \ -({ \ - long __retval; \ - freezer_do_not_count(); \ - __retval = schedule_timeout_killable(timeout); \ - freezer_count(); \ - __retval; \ -}) +static inline long freezable_schedule_timeout_killable(long timeout) +{ + long __retval; + freezer_do_not_count(); + __retval = schedule_timeout_killable(timeout); + freezer_count(); + return __retval; +} + +/* DO NOT ADD ANY NEW CALLERS OF THIS FUNCTION */ +static inline long freezable_schedule_timeout_killable_unsafe(long timeout) +{ + long __retval; + freezer_do_not_count(); + __retval = schedule_timeout_killable(timeout); + freezer_count_unsafe(); + return __retval; +} + +/* + * Like schedule_hrtimeout_range(), but should not block the freezer. Do not + * call this with locks held. + */ +static inline int freezable_schedule_hrtimeout_range(ktime_t *expires, + unsigned long delta, const enum hrtimer_mode mode) +{ + int __retval; + freezer_do_not_count(); + __retval = schedule_hrtimeout_range(expires, delta, mode); + freezer_count(); + return __retval; +} /* * Freezer-friendly wrappers around wait_event_interruptible(), @@ -177,33 +255,45 @@ static inline bool freezer_should_skip(struct task_struct *p) __retval; \ }) +/* DO NOT ADD ANY NEW CALLERS OF THIS FUNCTION */ +#define wait_event_freezekillable_unsafe(wq, condition) \ +({ \ + int __retval; \ + freezer_do_not_count(); \ + __retval = wait_event_killable(wq, (condition)); \ + freezer_count_unsafe(); \ + __retval; \ +}) + #define wait_event_freezable(wq, condition) \ ({ \ int __retval; \ - for (;;) { \ - __retval = wait_event_interruptible(wq, \ - (condition) || freezing(current)); \ - if (__retval || (condition)) \ - break; \ - try_to_freeze(); \ - } \ + freezer_do_not_count(); \ + __retval = wait_event_interruptible(wq, (condition)); \ + freezer_count(); \ __retval; \ }) #define wait_event_freezable_timeout(wq, condition, timeout) \ ({ \ long __retval = timeout; \ - for (;;) { \ - __retval = wait_event_interruptible_timeout(wq, \ - (condition) || freezing(current), \ - __retval); \ - if (__retval <= 0 || (condition)) \ - break; \ - try_to_freeze(); \ - } \ + freezer_do_not_count(); \ + __retval = wait_event_interruptible_timeout(wq, (condition), \ + __retval); \ + freezer_count(); \ __retval; \ }) +#define wait_event_freezable_exclusive(wq, condition) \ +({ \ + int __retval; \ + freezer_do_not_count(); \ + __retval = wait_event_interruptible_exclusive(wq, condition); \ + freezer_count(); \ + __retval; \ +}) + + #else /* !CONFIG_FREEZER */ static inline bool frozen(struct task_struct *p) { return false; } static inline bool freezing(struct task_struct *p) { return false; } @@ -225,18 +315,37 @@ static inline void set_freezable(void) {} #define freezable_schedule() schedule() +#define freezable_schedule_unsafe() schedule() + +#define freezable_schedule_timeout(timeout) schedule_timeout(timeout) + +#define freezable_schedule_timeout_interruptible(timeout) \ + schedule_timeout_interruptible(timeout) + #define freezable_schedule_timeout_killable(timeout) \ schedule_timeout_killable(timeout) +#define freezable_schedule_timeout_killable_unsafe(timeout) \ + schedule_timeout_killable(timeout) + +#define freezable_schedule_hrtimeout_range(expires, delta, mode) \ + schedule_hrtimeout_range(expires, delta, mode) + #define wait_event_freezable(wq, condition) \ wait_event_interruptible(wq, condition) #define wait_event_freezable_timeout(wq, condition, timeout) \ wait_event_interruptible_timeout(wq, condition, timeout) +#define wait_event_freezable_exclusive(wq, condition) \ + wait_event_interruptible_exclusive(wq, condition) + #define wait_event_freezekillable(wq, condition) \ wait_event_killable(wq, condition) +#define wait_event_freezekillable_unsafe(wq, condition) \ + wait_event_killable(wq, condition) + #endif /* !CONFIG_FREEZER */ #endif /* FREEZER_H_INCLUDED */ diff --git a/kernel/exit.c b/kernel/exit.c index 7bb73f9..6a05775 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -835,7 +835,7 @@ void do_exit(long code) /* * Make sure we are holding no locks: */ - debug_check_no_locks_held(tsk); + debug_check_no_locks_held(); /* * We can do this unlocked here. The futex code uses this flag * just to verify whether the pi state cleanup has been done diff --git a/kernel/freezer.c b/kernel/freezer.c index c38893b..8b2afc1 100644 --- a/kernel/freezer.c +++ b/kernel/freezer.c @@ -110,6 +110,18 @@ bool freeze_task(struct task_struct *p) { unsigned long flags; + /* + * This check can race with freezer_do_not_count, but worst case that + * will result in an extra wakeup being sent to the task. It does not + * race with freezer_count(), the barriers in freezer_count() and + * freezer_should_skip() ensure that either freezer_count() sees + * freezing == true in try_to_freeze() and freezes, or + * freezer_should_skip() sees !PF_FREEZE_SKIP and freezes the task + * normally. + */ + if (freezer_should_skip(p)) + return false; + spin_lock_irqsave(&freezer_lock, flags); if (!freezing(p) || frozen(p)) { spin_unlock_irqrestore(&freezer_lock, flags); diff --git a/kernel/futex.c b/kernel/futex.c index b26dcfc..d710fae 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -61,6 +61,7 @@ #include <linux/nsproxy.h> #include <linux/ptrace.h> #include <linux/sched/rt.h> +#include <linux/freezer.h> #include <asm/futex.h> @@ -1807,7 +1808,7 @@ static void futex_wait_queue_me(struct futex_hash_bucket *hb, struct futex_q *q, * is no timeout, or if it has yet to expire. */ if (!timeout || timeout->task) - schedule(); + freezable_schedule(); } __set_current_state(TASK_RUNNING); } diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index fd4b13b..3ee4d06 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -47,6 +47,7 @@ #include <linux/sched/sysctl.h> #include <linux/sched/rt.h> #include <linux/timer.h> +#include <linux/freezer.h> #include <asm/uaccess.h> @@ -1545,7 +1546,7 @@ static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mod t->task = NULL; if (likely(t->task)) - schedule(); + freezable_schedule(); hrtimer_cancel(&t->timer); mode = HRTIMER_MODE_ABS; diff --git a/kernel/lockdep.c b/kernel/lockdep.c index 1f3186b..e16c45b 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -4090,7 +4090,7 @@ void debug_check_no_locks_freed(const void *mem_from, unsigned long mem_len) } EXPORT_SYMBOL_GPL(debug_check_no_locks_freed); -static void print_held_locks_bug(struct task_struct *curr) +static void print_held_locks_bug(void) { if (!debug_locks_off()) return; @@ -4099,22 +4099,21 @@ static void print_held_locks_bug(struct task_struct *curr) printk("\n"); printk("=====================================\n"); - printk("[ BUG: lock held at task exit time! ]\n"); + printk("[ BUG: %s/%d still has locks held! ]\n", + current->comm, task_pid_nr(current)); print_kernel_ident(); printk("-------------------------------------\n"); - printk("%s/%d is exiting with locks still held!\n", - curr->comm, task_pid_nr(curr)); - lockdep_print_held_locks(curr); - + lockdep_print_held_locks(current); printk("\nstack backtrace:\n"); dump_stack(); } -void debug_check_no_locks_held(struct task_struct *task) +void debug_check_no_locks_held(void) { - if (unlikely(task->lockdep_depth > 0)) - print_held_locks_bug(task); + if (unlikely(current->lockdep_depth > 0)) + print_held_locks_bug(); } +EXPORT_SYMBOL_GPL(debug_check_no_locks_held); void debug_show_all_locks(void) { diff --git a/kernel/power/process.c b/kernel/power/process.c index 98088e0..fc0df84 100644 --- a/kernel/power/process.c +++ b/kernel/power/process.c @@ -30,9 +30,10 @@ static int try_to_freeze_tasks(bool user_only) unsigned int todo; bool wq_busy = false; struct timeval start, end; - u64 elapsed_csecs64; - unsigned int elapsed_csecs; + u64 elapsed_msecs64; + unsigned int elapsed_msecs; bool wakeup = false; + int sleep_usecs = USEC_PER_MSEC; do_gettimeofday(&start); @@ -68,22 +69,25 @@ static int try_to_freeze_tasks(bool user_only) /* * We need to retry, but first give the freezing tasks some - * time to enter the refrigerator. + * time to enter the refrigerator. Start with an initial + * 1 ms sleep followed by exponential backoff until 8 ms. */ - msleep(10); + usleep_range(sleep_usecs / 2, sleep_usecs); + if (sleep_usecs < 8 * USEC_PER_MSEC) + sleep_usecs *= 2; } do_gettimeofday(&end); - elapsed_csecs64 = timeval_to_ns(&end) - timeval_to_ns(&start); - do_div(elapsed_csecs64, NSEC_PER_SEC / 100); - elapsed_csecs = elapsed_csecs64; + elapsed_msecs64 = timeval_to_ns(&end) - timeval_to_ns(&start); + do_div(elapsed_msecs64, NSEC_PER_MSEC); + elapsed_msecs = elapsed_msecs64; if (todo) { printk("\n"); - printk(KERN_ERR "Freezing of tasks %s after %d.%02d seconds " + printk(KERN_ERR "Freezing of tasks %s after %d.%03d seconds " "(%d tasks refusing to freeze, wq_busy=%d):\n", wakeup ? "aborted" : "failed", - elapsed_csecs / 100, elapsed_csecs % 100, + elapsed_msecs / 1000, elapsed_msecs % 1000, todo - wq_busy, wq_busy); if (!wakeup) { @@ -96,8 +100,8 @@ static int try_to_freeze_tasks(bool user_only) read_unlock(&tasklist_lock); } } else { - printk("(elapsed %d.%02d seconds) ", elapsed_csecs / 100, - elapsed_csecs % 100); + printk("(elapsed %d.%03d seconds) ", elapsed_msecs / 1000, + elapsed_msecs % 1000); } return todo ? -EBUSY : 0; diff --git a/kernel/signal.c b/kernel/signal.c index 113411b..50e4107 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2848,7 +2848,7 @@ int do_sigtimedwait(const sigset_t *which, siginfo_t *info, recalc_sigpending(); spin_unlock_irq(&tsk->sighand->siglock); - timeout = schedule_timeout_interruptible(timeout); + timeout = freezable_schedule_timeout_interruptible(timeout); spin_lock_irq(&tsk->sighand->siglock); __set_task_blocked(tsk, &tsk->real_blocked); diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c index 5356b12..77d251e 100644 --- a/net/sunrpc/sched.c +++ b/net/sunrpc/sched.c @@ -254,7 +254,7 @@ static int rpc_wait_bit_killable(void *word) { if (fatal_signal_pending(current)) return -ERESTARTSYS; - freezable_schedule(); + freezable_schedule_unsafe(); return 0; } diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index 826e099..c4ce243 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -114,6 +114,7 @@ #include <linux/mount.h> #include <net/checksum.h> #include <linux/security.h> +#include <linux/freezer.h> struct hlist_head unix_socket_table[2 * UNIX_HASH_SIZE]; EXPORT_SYMBOL_GPL(unix_socket_table); @@ -1879,7 +1880,7 @@ static long unix_stream_data_wait(struct sock *sk, long timeo, set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); unix_state_unlock(sk); - timeo = schedule_timeout(timeo); + timeo = freezable_schedule_timeout(timeo); unix_state_lock(sk); clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); } |