From patchwork Fri Jun 11 08:45:00 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Zijlstra X-Patchwork-Id: 458837 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BA475C48BE0 for ; Fri, 11 Jun 2021 08:47:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9901861364 for ; Fri, 11 Jun 2021 08:47:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231301AbhFKIs7 (ORCPT ); Fri, 11 Jun 2021 04:48:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34408 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231295AbhFKIs6 (ORCPT ); Fri, 11 Jun 2021 04:48:58 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C9069C061574; Fri, 11 Jun 2021 01:47:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Type:MIME-Version:Message-ID: Subject:Cc:To:From:Date:Sender:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:In-Reply-To:References; bh=P5rboT07DI4G7I061GAub4oIhSVt43wCBwQvlA8MTBs=; b=B7apHNVJuBmNLHnV5a/5NwNoc+ z2aDOFBg6+KC2nKsxBZ5v7+AY3dKDjBl4WFYddzcvV66MHAXvFbDfGY6Cnha5vmziDvJRqikclXqp xxZ7wY84Jj0NV7wbBWsykJW2/C0ZQOjQPpKsdkjglz+RaxO6XUqDAO+LR624dPFaXF1E1d8lHtjEU xyvaGmkZ97tZsbwaCNTrSIGBstKSuwe+SGoOj+ZAzPHhVs/VxtpVV1kZ43PrLrux3u7ts1bZcNoXl Gr0DwAW2NGWs0QLDnHwJFCiR+L8T7Ut/ltMjxnhbtNGSK2+aoZ6X0Vq3/H1Yjjbosy8L8k5bX+/Bc MnUNugmg==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94 #2 (Red Hat Linux)) id 1lrcmj-002aD6-Bx; Fri, 11 Jun 2021 08:45:29 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 5A2193001E3; Fri, 11 Jun 2021 10:45:00 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 39ED72BC12DA2; Fri, 11 Jun 2021 10:45:00 +0200 (CEST) Date: Fri, 11 Jun 2021 10:45:00 +0200 From: Peter Zijlstra To: rjw@rjwysocki.net, Oleg Nesterov , mingo@kernel.org, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, mgorman@suse.de, Will Deacon Cc: Tejun Heo , linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org Subject: [PATCH] freezer,sched: Rewrite core freezer logic Message-ID: MIME-Version: 1.0 Content-Disposition: inline Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Rewrite the core freezer to behave better wrt thawing. By replacing PF_FROZEN with TASK_FROZEN, a special block state, it is ensured frozen tasks stay frozen until explicitly thawed and don't randomly wake up early, as is currently possible. As such, it does away with PF_FROZEN and PF_FREEZER_SKIP, freeing up two PF_flags (yay). The freezing was tested, and found good, using: echo freezer > /sys/power/pm_test echo mem > /sys/power/state Even while having a GDB session active. Another notable bit is in init/do_mounts_initrd.c; afaict that has been 'broken' for quite a while and is simply removed. Requested-by: Will Deacon Signed-off-by: Peter Zijlstra (Intel) --- drivers/android/binder.c | 4 drivers/media/pci/pt3/pt3.c | 4 fs/cifs/inode.c | 4 fs/cifs/transport.c | 5 fs/coredump.c | 4 fs/nfs/file.c | 3 fs/nfs/inode.c | 12 -- fs/nfs/nfs3proc.c | 3 fs/nfs/nfs4proc.c | 14 +- fs/nfs/nfs4state.c | 3 fs/nfs/pnfs.c | 4 fs/xfs/xfs_trans_ail.c | 8 - include/linux/completion.h | 2 include/linux/freezer.h | 244 +---------------------------------------- include/linux/sched.h | 16 ++ include/linux/sunrpc/sched.h | 7 - include/linux/wait.h | 40 +++++- init/do_mounts_initrd.c | 7 - kernel/cgroup/legacy_freezer.c | 23 +-- kernel/exit.c | 4 kernel/fork.c | 4 kernel/freezer.c | 116 +++++++++++++------ kernel/futex.c | 4 kernel/hung_task.c | 4 kernel/power/main.c | 5 kernel/power/process.c | 10 - kernel/sched/completion.c | 16 ++ kernel/sched/core.c | 2 kernel/signal.c | 14 +- kernel/time/hrtimer.c | 4 mm/khugepaged.c | 4 net/sunrpc/sched.c | 12 -- net/unix/af_unix.c | 8 - 33 files changed, 232 insertions(+), 382 deletions(-) --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -3712,10 +3712,9 @@ static int binder_wait_for_work(struct b struct binder_proc *proc = thread->proc; int ret = 0; - freezer_do_not_count(); binder_inner_proc_lock(proc); for (;;) { - prepare_to_wait(&thread->wait, &wait, TASK_INTERRUPTIBLE); + prepare_to_wait(&thread->wait, &wait, TASK_INTERRUPTIBLE|TASK_FREEZABLE); if (binder_has_work_ilocked(thread, do_proc_work)) break; if (do_proc_work) @@ -3732,7 +3731,6 @@ static int binder_wait_for_work(struct b } finish_wait(&thread->wait, &wait); binder_inner_proc_unlock(proc); - freezer_count(); return ret; } --- a/drivers/media/pci/pt3/pt3.c +++ b/drivers/media/pci/pt3/pt3.c @@ -445,8 +445,8 @@ static int pt3_fetch_thread(void *data) pt3_proc_dma(adap); delay = ktime_set(0, PT3_FETCH_DELAY * NSEC_PER_MSEC); - set_current_state(TASK_UNINTERRUPTIBLE); - freezable_schedule_hrtimeout_range(&delay, + set_current_state(TASK_UNINTERRUPTIBLE|TASK_FREEZABLE); + schedule_hrtimeout_range(&delay, PT3_FETCH_DELAY_DELTA * NSEC_PER_MSEC, HRTIMER_MODE_REL); } --- a/fs/cifs/inode.c +++ b/fs/cifs/inode.c @@ -2280,7 +2280,7 @@ cifs_invalidate_mapping(struct inode *in static int cifs_wait_bit_killable(struct wait_bit_key *key, int mode) { - freezable_schedule_unsafe(); + schedule(); if (signal_pending_state(mode, current)) return -ERESTARTSYS; return 0; @@ -2297,7 +2297,7 @@ cifs_revalidate_mapping(struct inode *in return 0; rc = wait_on_bit_lock_action(flags, CIFS_INO_LOCK, cifs_wait_bit_killable, - TASK_KILLABLE); + TASK_KILLABLE|TASK_FREEZABLE_UNSAFE); if (rc) return rc; --- a/fs/cifs/transport.c +++ b/fs/cifs/transport.c @@ -771,8 +771,9 @@ wait_for_response(struct TCP_Server_Info { int error; - error = wait_event_freezekillable_unsafe(server->response_q, - midQ->mid_state != MID_REQUEST_SUBMITTED); + error = wait_event_state(server->response_q, + midQ->mid_state != MID_REQUEST_SUBMITTED, + (TASK_KILLABLE|TASK_FREEZABLE_UNSAFE)); if (error < 0) return -ERESTARTSYS; --- a/fs/coredump.c +++ b/fs/coredump.c @@ -465,9 +465,7 @@ static int coredump_wait(int exit_code, if (core_waiters > 0) { struct core_thread *ptr; - freezer_do_not_count(); - wait_for_completion(&core_state->startup); - freezer_count(); + wait_for_completion_freezable(&core_state->startup); /* * Wait for all the threads to become inactive, so that * all the thread context (extended register state, like --- a/fs/nfs/file.c +++ b/fs/nfs/file.c @@ -558,7 +558,8 @@ static vm_fault_t nfs_vm_page_mkwrite(st nfs_fscache_wait_on_page_write(NFS_I(inode), page); wait_on_bit_action(&NFS_I(inode)->flags, NFS_INO_INVALIDATING, - nfs_wait_bit_killable, TASK_KILLABLE); + nfs_wait_bit_killable, + TASK_KILLABLE|TASK_FREEZABLE_UNSAFE); lock_page(page); mapping = page_file_mapping(page); --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -72,18 +72,13 @@ nfs_fattr_to_ino_t(struct nfs_fattr *fat return nfs_fileid_to_ino_t(fattr->fileid); } -static int nfs_wait_killable(int mode) +int nfs_wait_bit_killable(struct wait_bit_key *key, int mode) { - freezable_schedule_unsafe(); + schedule(); if (signal_pending_state(mode, current)) return -ERESTARTSYS; return 0; } - -int nfs_wait_bit_killable(struct wait_bit_key *key, int mode) -{ - return nfs_wait_killable(mode); -} EXPORT_SYMBOL_GPL(nfs_wait_bit_killable); /** @@ -1323,7 +1318,8 @@ int nfs_clear_invalid_mapping(struct add */ for (;;) { ret = wait_on_bit_action(bitlock, NFS_INO_INVALIDATING, - nfs_wait_bit_killable, TASK_KILLABLE); + nfs_wait_bit_killable, + TASK_KILLABLE|TASK_FREEZABLE_UNSAFE); if (ret) goto out; spin_lock(&inode->i_lock); --- a/fs/nfs/nfs3proc.c +++ b/fs/nfs/nfs3proc.c @@ -36,7 +36,8 @@ nfs3_rpc_wrapper(struct rpc_clnt *clnt, res = rpc_call_sync(clnt, msg, flags); if (res != -EJUKEBOX) break; - freezable_schedule_timeout_killable_unsafe(NFS_JUKEBOX_RETRY_TIME); + __set_current_state(TASK_KILLABLE|TASK_FREEZABLE_UNSAFE); + schedule_timeout(NFS_JUKEBOX_RETRY_TIME); res = -ERESTARTSYS; } while (!fatal_signal_pending(current)); return res; --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -411,8 +411,8 @@ static int nfs4_delay_killable(long *tim { might_sleep(); - freezable_schedule_timeout_killable_unsafe( - nfs4_update_delay(timeout)); + __set_current_state(TASK_KILLABLE|TASK_FREEZABLE_UNSAFE); + schedule_timeout(nfs4_update_delay(timeout)); if (!__fatal_signal_pending(current)) return 0; return -EINTR; @@ -422,7 +422,8 @@ static int nfs4_delay_interruptible(long { might_sleep(); - freezable_schedule_timeout_interruptible_unsafe(nfs4_update_delay(timeout)); + __set_current_state(TASK_INTERRUPTIBLE|TASK_FREEZABLE_UNSAFE); + schedule_timeout(nfs4_update_delay(timeout)); if (!signal_pending(current)) return 0; return __fatal_signal_pending(current) ? -EINTR :-ERESTARTSYS; @@ -7280,7 +7281,8 @@ nfs4_retry_setlk_simple(struct nfs4_stat status = nfs4_proc_setlk(state, cmd, request); if ((status != -EAGAIN) || IS_SETLK(cmd)) break; - freezable_schedule_timeout_interruptible(timeout); + __set_current_state(TASK_INTERRUPTIBLE|TASK_FREEZABLE); + schedule_timeout(timeout); timeout *= 2; timeout = min_t(unsigned long, NFS4_LOCK_MAXTIMEOUT, timeout); status = -ERESTARTSYS; @@ -7348,10 +7350,8 @@ nfs4_retry_setlk(struct nfs4_state *stat break; status = -ERESTARTSYS; - freezer_do_not_count(); - wait_woken(&waiter.wait, TASK_INTERRUPTIBLE, + wait_woken(&waiter.wait, TASK_INTERRUPTIBLE|TASK_FREEZABLE, NFS4_LOCK_MAXTIMEOUT); - freezer_count(); } while (!signalled()); remove_wait_queue(q, &waiter.wait); --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -1307,7 +1307,8 @@ int nfs4_wait_clnt_recover(struct nfs_cl refcount_inc(&clp->cl_count); res = wait_on_bit_action(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING, - nfs_wait_bit_killable, TASK_KILLABLE); + nfs_wait_bit_killable, + TASK_KILLABLE|TASK_FREEZABLE_UNSAFE); if (res) goto out; if (clp->cl_cons_state < 0) --- a/fs/nfs/pnfs.c +++ b/fs/nfs/pnfs.c @@ -1897,7 +1897,7 @@ static int pnfs_prepare_to_retry_layoutg pnfs_layoutcommit_inode(lo->plh_inode, false); return wait_on_bit_action(&lo->plh_flags, NFS_LAYOUT_RETURN, nfs_wait_bit_killable, - TASK_KILLABLE); + TASK_KILLABLE|TASK_FREEZABLE_UNSAFE); } static void nfs_layoutget_begin(struct pnfs_layout_hdr *lo) @@ -3172,7 +3172,7 @@ pnfs_layoutcommit_inode(struct inode *in status = wait_on_bit_lock_action(&nfsi->flags, NFS_INO_LAYOUTCOMMITTING, nfs_wait_bit_killable, - TASK_KILLABLE); + TASK_KILLABLE|TASK_FREEZABLE_UNSAFE); if (status) goto out; } --- a/fs/xfs/xfs_trans_ail.c +++ b/fs/xfs/xfs_trans_ail.c @@ -585,9 +585,9 @@ xfsaild( while (1) { if (tout && tout <= 20) - set_current_state(TASK_KILLABLE); + set_current_state(TASK_KILLABLE|TASK_FREEZABLE); else - set_current_state(TASK_INTERRUPTIBLE); + set_current_state(TASK_INTERRUPTIBLE|TASK_FREEZABLE); /* * Check kthread_should_stop() after we set the task state to @@ -636,14 +636,14 @@ xfsaild( ailp->ail_target == ailp->ail_target_prev && list_empty(&ailp->ail_buf_list)) { spin_unlock(&ailp->ail_lock); - freezable_schedule(); + schedule(); tout = 0; continue; } spin_unlock(&ailp->ail_lock); if (tout) - freezable_schedule_timeout(msecs_to_jiffies(tout)); + schedule_timeout(msecs_to_jiffies(tout)); __set_current_state(TASK_RUNNING); --- a/include/linux/completion.h +++ b/include/linux/completion.h @@ -100,9 +100,11 @@ static inline void reinit_completion(str } extern void wait_for_completion(struct completion *); +extern void wait_for_completion_freezable(struct completion *); extern void wait_for_completion_io(struct completion *); extern int wait_for_completion_interruptible(struct completion *x); extern int wait_for_completion_killable(struct completion *x); +extern int wait_for_completion_killable_freezable(struct completion *x); extern unsigned long wait_for_completion_timeout(struct completion *x, unsigned long timeout); extern unsigned long wait_for_completion_io_timeout(struct completion *x, --- a/include/linux/freezer.h +++ b/include/linux/freezer.h @@ -8,9 +8,11 @@ #include #include #include +#include #ifdef CONFIG_FREEZER -extern atomic_t system_freezing_cnt; /* nr of freezing conds in effect */ +DECLARE_STATIC_KEY_FALSE(freezer_active); + extern bool pm_freezing; /* PM freezing in effect */ extern bool pm_nosig_freezing; /* PM nosig freezing in effect */ @@ -22,10 +24,7 @@ extern unsigned int freeze_timeout_msecs /* * Check if a process has been frozen */ -static inline bool frozen(struct task_struct *p) -{ - return p->flags & PF_FROZEN; -} +extern bool frozen(struct task_struct *p); extern bool freezing_slow_path(struct task_struct *p); @@ -34,9 +33,10 @@ extern bool freezing_slow_path(struct ta */ static inline bool freezing(struct task_struct *p) { - if (likely(!atomic_read(&system_freezing_cnt))) - return false; - return freezing_slow_path(p); + if (static_branch_unlikely(&freezer_active)) + return freezing_slow_path(p); + + return false; } /* Takes and releases task alloc lock using task_lock() */ @@ -48,23 +48,14 @@ extern int freeze_kernel_threads(void); extern void thaw_processes(void); extern void thaw_kernel_threads(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) +static inline bool try_to_freeze(void) { might_sleep(); if (likely(!freezing(current))) return false; - 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(); + return __refrigerator(false); } extern bool freeze_task(struct task_struct *p); @@ -79,195 +70,6 @@ static inline bool cgroup_freezing(struc } #endif /* !CONFIG_CGROUP_FREEZER */ -/* - * The PF_FREEZER_SKIP flag should be set by a vfork parent right before it - * calls wait_for_completion(&vfork) and reset right after it returns from this - * function. Next, the parent should call try_to_freeze() to freeze itself - * appropriately in case the child has exited before the freezing of tasks is - * complete. However, we don't want kernel threads to be frozen in unexpected - * places, so we allow them to block freeze_processes() instead or to set - * PF_NOFREEZE if needed. Fortunately, in the ____call_usermodehelper() case the - * parent won't really block freeze_processes(), since ____call_usermodehelper() - * (the child) does a little before exec/exit and it can't be frozen before - * waking up the parent. - */ - - -/** - * freezer_do_not_count - tell freezer to ignore %current - * - * Tell freezers to ignore the current task when determining whether the - * target frozen state is reached. IOW, the current task will be - * considered frozen enough by freezers. - * - * The caller shouldn't do anything which isn't allowed for a frozen task - * until freezer_cont() is called. Usually, freezer[_do_not]_count() pair - * wrap a scheduling operation and nothing much else. - */ -static inline void freezer_do_not_count(void) -{ - current->flags |= PF_FREEZER_SKIP; -} - -/** - * freezer_count - tell freezer to stop ignoring %current - * - * Undo freezer_do_not_count(). It tells freezers that %current should be - * considered again and tries to freeze if freezing condition is already in - * effect. - */ -static inline void freezer_count(void) -{ - current->flags &= ~PF_FREEZER_SKIP; - /* - * If freezing is in progress, the following paired with smp_mb() - * in freezer_should_skip() ensures that either we see %true - * freezing() or freezer_should_skip() sees !PF_FREEZER_SKIP. - */ - smp_mb(); - 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 - * @p: task in quesion - * - * This function is used by freezers after establishing %true freezing() to - * test whether a task should be skipped when determining the target frozen - * state is reached. IOW, if this function returns %true, @p is considered - * frozen enough. - */ -static inline bool freezer_should_skip(struct task_struct *p) -{ - /* - * The following smp_mb() paired with the one in freezer_count() - * ensures that either freezer_count() sees %true freezing() or we - * see cleared %PF_FREEZER_SKIP and return %false. This makes it - * impossible for a task to slip frozen state testing after - * clearing %PF_FREEZER_SKIP. - */ - smp_mb(); - return p->flags & PF_FREEZER_SKIP; -} - -/* - * 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. */ -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 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; -} - -/* DO NOT ADD ANY NEW CALLERS OF THIS FUNCTION */ -static inline long freezable_schedule_timeout_interruptible_unsafe(long timeout) -{ - long __retval; - - freezer_do_not_count(); - __retval = schedule_timeout_interruptible(timeout); - freezer_count_unsafe(); - return __retval; -} - -/* Like schedule_timeout_killable(), but should not block the freezer. */ -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, - u64 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(), - * wait_event_killable() and wait_event_interruptible_timeout(), originally - * defined in - */ - -/* 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; \ -}) - #else /* !CONFIG_FREEZER */ static inline bool frozen(struct task_struct *p) { return false; } static inline bool freezing(struct task_struct *p) { return false; } @@ -281,35 +83,9 @@ static inline void thaw_kernel_threads(v static inline bool try_to_freeze(void) { return false; } -static inline void freezer_do_not_count(void) {} static inline void freezer_count(void) {} -static inline int freezer_should_skip(struct task_struct *p) { return 0; } 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_interruptible_unsafe(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_freezekillable_unsafe(wq, condition) \ - wait_event_killable(wq, condition) - #endif /* !CONFIG_FREEZER */ #endif /* FREEZER_H_INCLUDED */ --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -95,7 +95,15 @@ struct task_group; #define TASK_WAKING 0x0200 #define TASK_NOLOAD 0x0400 #define TASK_NEW 0x0800 -#define TASK_STATE_MAX 0x1000 +#define TASK_FREEZABLE 0x1000 +#define __TASK_FREEZABLE_UNSAFE (0x2000 * IS_ENABLED(CONFIG_LOCKDEP)) +#define TASK_FROZEN 0x4000 +#define TASK_STATE_MAX 0x8000 + +/* + * DO NOT ADD ANY NEW USERS ! + */ +#define TASK_FREEZABLE_UNSAFE (TASK_FREEZABLE | __TASK_FREEZABLE_UNSAFE) /* Convenience macros for the sake of set_current_state: */ #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) @@ -126,7 +134,8 @@ struct task_group; * the comment with set_special_state(). */ #define is_special_task_state(state) \ - ((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | TASK_DEAD)) + ((state) & (__TASK_STOPPED | __TASK_TRACED | \ + TASK_PARKED | TASK_DEAD | TASK_FROZEN)) #define __set_current_state(state_value) \ do { \ @@ -146,6 +155,7 @@ struct task_group; do { \ unsigned long flags; /* may shadow */ \ WARN_ON_ONCE(!is_special_task_state(state_value)); \ + WARN_ON_ONCE(state_value == TASK_FROZEN); \ raw_spin_lock_irqsave(¤t->pi_lock, flags); \ current->task_state_change = _THIS_IP_; \ current->state = (state_value); \ @@ -1579,7 +1589,6 @@ extern struct pid *cad_pid; #define PF_USED_MATH 0x00002000 /* If unset the fpu must be initialized before use */ #define PF_USED_ASYNC 0x00004000 /* Used async_schedule*(), used by module init */ #define PF_NOFREEZE 0x00008000 /* This thread should not be frozen */ -#define PF_FROZEN 0x00010000 /* Frozen for system suspend */ #define PF_KSWAPD 0x00020000 /* I am kswapd */ #define PF_MEMALLOC_NOFS 0x00040000 /* All allocation requests will inherit GFP_NOFS */ #define PF_MEMALLOC_NOIO 0x00080000 /* All allocation requests will inherit GFP_NOIO */ @@ -1591,7 +1600,6 @@ extern struct pid *cad_pid; #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */ #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ #define PF_MEMALLOC_PIN 0x10000000 /* Allocation context constrained to zones which allow long term pinning. */ -#define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */ #define PF_SUSPEND_TASK 0x80000000 /* This thread called freeze_processes() and should not be frozen */ /* --- a/include/linux/sunrpc/sched.h +++ b/include/linux/sunrpc/sched.h @@ -263,7 +263,7 @@ int rpc_malloc(struct rpc_task *); void rpc_free(struct rpc_task *); int rpciod_up(void); void rpciod_down(void); -int __rpc_wait_for_completion_task(struct rpc_task *task, wait_bit_action_f *); +int rpc_wait_for_completion_task(struct rpc_task *task); #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) struct net; void rpc_show_tasks(struct net *); @@ -274,11 +274,6 @@ extern struct workqueue_struct *rpciod_w extern struct workqueue_struct *xprtiod_workqueue; void rpc_prepare_task(struct rpc_task *task); -static inline int rpc_wait_for_completion_task(struct rpc_task *task) -{ - return __rpc_wait_for_completion_task(task, NULL); -} - #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) || IS_ENABLED(CONFIG_TRACEPOINTS) static inline const char * rpc_qname(const struct rpc_wait_queue *q) { --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -335,8 +335,8 @@ do { \ } while (0) #define __wait_event_freezable(wq_head, condition) \ - ___wait_event(wq_head, condition, TASK_INTERRUPTIBLE, 0, 0, \ - freezable_schedule()) + ___wait_event(wq_head, condition, (TASK_INTERRUPTIBLE|TASK_FREEZABLE), \ + 0, 0, schedule()) /** * wait_event_freezable - sleep (or freeze) until a condition gets true @@ -394,8 +394,8 @@ do { \ #define __wait_event_freezable_timeout(wq_head, condition, timeout) \ ___wait_event(wq_head, ___wait_cond_timeout(condition), \ - TASK_INTERRUPTIBLE, 0, timeout, \ - __ret = freezable_schedule_timeout(__ret)) + (TASK_INTERRUPTIBLE|TASK_FREEZABLE), 0, timeout, \ + __ret = schedule_timeout(__ret)) /* * like wait_event_timeout() -- except it uses TASK_INTERRUPTIBLE to avoid @@ -615,8 +615,8 @@ do { \ #define __wait_event_freezable_exclusive(wq, condition) \ - ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 1, 0, \ - freezable_schedule()) + ___wait_event(wq, condition, (TASK_INTERRUPTIBLE|TASK_FREEZABLE), 1, 0,\ + schedule()) #define wait_event_freezable_exclusive(wq, condition) \ ({ \ @@ -905,6 +905,34 @@ extern int do_wait_intr_irq(wait_queue_h __ret; \ }) +#define __wait_event_state(wq, condition, state) \ + ___wait_event(wq, condition, state, 0, 0, schedule()) + +/** + * wait_event_state - sleep until a condition gets true + * @wq_head: the waitqueue to wait on + * @condition: a C expression for the event to wait for + * @state: state to sleep in + * + * The process is put to sleep (@state) until the @condition evaluates to true + * or a signal is received. The @condition is checked each time the waitqueue + * @wq_head is woken up. + * + * wake_up() has to be called after changing any variable that could + * change the result of the wait condition. + * + * The function will return -ERESTARTSYS if it was interrupted by a + * signal and 0 if @condition evaluated to true. + */ +#define wait_event_state(wq_head, condition, state) \ +({ \ + int __ret = 0; \ + might_sleep(); \ + if (!(condition)) \ + __ret = __wait_event_state(wq_head, condition, state); \ + __ret; \ +}) + #define __wait_event_killable_timeout(wq_head, condition, timeout) \ ___wait_event(wq_head, ___wait_cond_timeout(condition), \ TASK_KILLABLE, 0, timeout, \ --- a/init/do_mounts_initrd.c +++ b/init/do_mounts_initrd.c @@ -80,10 +80,9 @@ static void __init handle_initrd(void) init_chdir("/old"); /* - * In case that a resume from disk is carried out by linuxrc or one of - * its children, we need to tell the freezer not to wait for us. + * PF_FREEZER_SKIP is pointless because UMH is laundered through a + * workqueue and that doesn't have the current context. */ - current->flags |= PF_FREEZER_SKIP; info = call_usermodehelper_setup("/linuxrc", argv, envp_init, GFP_KERNEL, init_linuxrc, NULL, NULL); @@ -91,8 +90,6 @@ static void __init handle_initrd(void) return; call_usermodehelper_exec(info, UMH_WAIT_PROC); - current->flags &= ~PF_FREEZER_SKIP; - /* move initrd to rootfs' /old */ init_mount("..", ".", NULL, MS_MOVE, NULL); /* switch root and cwd back to / of rootfs */ --- a/kernel/cgroup/legacy_freezer.c +++ b/kernel/cgroup/legacy_freezer.c @@ -113,7 +113,7 @@ static int freezer_css_online(struct cgr if (parent && (parent->state & CGROUP_FREEZING)) { freezer->state |= CGROUP_FREEZING_PARENT | CGROUP_FROZEN; - atomic_inc(&system_freezing_cnt); + static_branch_inc(&freezer_active); } mutex_unlock(&freezer_mutex); @@ -134,7 +134,7 @@ static void freezer_css_offline(struct c mutex_lock(&freezer_mutex); if (freezer->state & CGROUP_FREEZING) - atomic_dec(&system_freezing_cnt); + static_branch_dec(&freezer_active); freezer->state = 0; @@ -179,6 +179,7 @@ static void freezer_attach(struct cgroup __thaw_task(task); } else { freeze_task(task); + /* clear FROZEN and propagate upwards */ while (freezer && (freezer->state & CGROUP_FROZEN)) { freezer->state &= ~CGROUP_FROZEN; @@ -271,16 +272,8 @@ static void update_if_frozen(struct cgro css_task_iter_start(css, 0, &it); while ((task = css_task_iter_next(&it))) { - if (freezing(task)) { - /* - * freezer_should_skip() indicates that the task - * should be skipped when determining freezing - * completion. Consider it frozen in addition to - * the usual frozen condition. - */ - if (!frozen(task) && !freezer_should_skip(task)) - goto out_iter_end; - } + if (freezing(task) && !frozen(task)) + goto out_iter_end; } freezer->state |= CGROUP_FROZEN; @@ -357,7 +350,7 @@ static void freezer_apply_state(struct f if (freeze) { if (!(freezer->state & CGROUP_FREEZING)) - atomic_inc(&system_freezing_cnt); + static_branch_inc(&freezer_active); freezer->state |= state; freeze_cgroup(freezer); } else { @@ -366,9 +359,9 @@ static void freezer_apply_state(struct f freezer->state &= ~state; if (!(freezer->state & CGROUP_FREEZING)) { - if (was_freezing) - atomic_dec(&system_freezing_cnt); freezer->state &= ~CGROUP_FROZEN; + if (was_freezing) + static_branch_dec(&freezer_active); unfreeze_cgroup(freezer); } } --- a/kernel/exit.c +++ b/kernel/exit.c @@ -468,10 +468,10 @@ static void exit_mm(void) complete(&core_state->startup); for (;;) { - set_current_state(TASK_UNINTERRUPTIBLE); + set_current_state(TASK_UNINTERRUPTIBLE|TASK_FREEZABLE); if (!self.task) /* see coredump_finish() */ break; - freezable_schedule(); + schedule(); } __set_current_state(TASK_RUNNING); mmap_read_lock(mm); --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1272,11 +1272,9 @@ static int wait_for_vfork_done(struct ta { int killed; - freezer_do_not_count(); cgroup_enter_frozen(); - killed = wait_for_completion_killable(vfork); + killed = wait_for_completion_killable_freezable(vfork); cgroup_leave_frozen(false); - freezer_count(); if (killed) { task_lock(child); --- a/kernel/freezer.c +++ b/kernel/freezer.c @@ -13,8 +13,8 @@ #include /* total number of freezing conditions in effect */ -atomic_t system_freezing_cnt = ATOMIC_INIT(0); -EXPORT_SYMBOL(system_freezing_cnt); +DEFINE_STATIC_KEY_FALSE(freezer_active); +EXPORT_SYMBOL(freezer_active); /* indicate whether PM freezing is in effect, protected by * system_transition_mutex @@ -29,7 +29,7 @@ static DEFINE_SPINLOCK(freezer_lock); * freezing_slow_path - slow path for testing whether a task needs to be frozen * @p: task to be tested * - * This function is called by freezing() if system_freezing_cnt isn't zero + * This function is called by freezing() if freezer_active isn't zero * and tests whether @p needs to enter and stay in frozen state. Can be * called under any context. The freezers are responsible for ensuring the * target tasks see the updated state. @@ -52,41 +52,67 @@ bool freezing_slow_path(struct task_stru } EXPORT_SYMBOL(freezing_slow_path); +/* Recursion relies on tail-call optimization to not blow away the stack */ +static bool __frozen(struct task_struct *p) +{ + if (p->state == TASK_FROZEN) + return true; + + /* + * If stuck in TRACED, and the ptracer is FROZEN, we're frozen too. + */ + if (task_is_traced(p)) + return frozen(rcu_dereference(p->parent)); + + /* + * If stuck in STOPPED and the parent is FROZEN, we're frozen too. + */ + if (task_is_stopped(p)) + return frozen(rcu_dereference(p->real_parent)); + + return false; +} + +bool frozen(struct task_struct *p) +{ + bool ret; + + rcu_read_lock(); + ret = __frozen(p); + rcu_read_unlock(); + + return ret; +} + /* Refrigerator is place where frozen processes are stored :-). */ bool __refrigerator(bool check_kthr_stop) { - /* Hmm, should we be allowed to suspend when there are realtime - processes around? */ + unsigned int state = READ_ONCE(current->state); bool was_frozen = false; - long save = current->state; pr_debug("%s entered refrigerator\n", current->comm); + WARN_ON_ONCE(state && !(state & TASK_NORMAL)); + for (;;) { - set_current_state(TASK_UNINTERRUPTIBLE); + bool freeze; + + set_current_state(TASK_FROZEN); spin_lock_irq(&freezer_lock); - current->flags |= PF_FROZEN; - if (!freezing(current) || - (check_kthr_stop && kthread_should_stop())) - current->flags &= ~PF_FROZEN; + freeze = freezing(current) && !(check_kthr_stop && kthread_should_stop()); spin_unlock_irq(&freezer_lock); - if (!(current->flags & PF_FROZEN)) + if (!freeze) break; + was_frozen = true; schedule(); } + __set_current_state(TASK_RUNNING); pr_debug("%s left refrigerator\n", current->comm); - /* - * Restore saved task state before returning. The mb'd version - * needs to be used; otherwise, it might silently break - * synchronization which depends on ordered task state change. - */ - set_current_state(save); - return was_frozen; } EXPORT_SYMBOL(__refrigerator); @@ -101,6 +127,38 @@ static void fake_signal_wake_up(struct t } } +/* See set_special_state(); serializes against ttwu() */ +static bool __freeze_task(struct task_struct *p) +{ + unsigned long flags; + unsigned int state; + bool frozen = false; + + raw_spin_lock_irqsave(&p->pi_lock, flags); + state = READ_ONCE(p->state); + if (state & TASK_FREEZABLE) { + /* + * Only TASK_NORMAL can be augmented with TASK_FREEZABLE, + * since they can suffer spurious wakeups. + */ + WARN_ON_ONCE(!(state & TASK_NORMAL)); + +#ifdef CONFIG_LOCKDEP + /* + * It's dangerous to freeze with locks held; there be dragons there. + */ + if (!(state & __TASK_FREEZABLE_UNSAFE)) + WARN_ON_ONCE(debug_locks && p->lockdep_depth); +#endif + + p->state = TASK_FROZEN; + frozen = true; + } + raw_spin_unlock_irqrestore(&p->pi_lock, flags); + + return frozen; +} + /** * freeze_task - send a freeze request to given task * @p: task to send the request to @@ -116,20 +174,8 @@ 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)) { + if (!freezing(p) || frozen(p) || __freeze_task(p)) { spin_unlock_irqrestore(&freezer_lock, flags); return false; } @@ -137,7 +183,7 @@ bool freeze_task(struct task_struct *p) if (!(p->flags & PF_KTHREAD)) fake_signal_wake_up(p); else - wake_up_state(p, TASK_INTERRUPTIBLE); + wake_up_state(p, TASK_INTERRUPTIBLE); // TASK_NORMAL ?!? spin_unlock_irqrestore(&freezer_lock, flags); return true; @@ -148,8 +194,8 @@ void __thaw_task(struct task_struct *p) unsigned long flags; spin_lock_irqsave(&freezer_lock, flags); - if (frozen(p)) - wake_up_process(p); + WARN_ON_ONCE(freezing(p)); + wake_up_state(p, TASK_FROZEN); spin_unlock_irqrestore(&freezer_lock, flags); } --- a/kernel/futex.c +++ b/kernel/futex.c @@ -2582,7 +2582,7 @@ static void futex_wait_queue_me(struct f * queue_me() calls spin_unlock() upon completion, both serializing * access to the hash list and forcing another memory barrier. */ - set_current_state(TASK_INTERRUPTIBLE); + set_current_state(TASK_INTERRUPTIBLE|TASK_FREEZABLE); queue_me(q, hb); /* Arm the timer */ @@ -2600,7 +2600,7 @@ static void futex_wait_queue_me(struct f * is no timeout, or if it has yet to expire. */ if (!timeout || timeout->task) - freezable_schedule(); + schedule(); } __set_current_state(TASK_RUNNING); } --- a/kernel/hung_task.c +++ b/kernel/hung_task.c @@ -92,8 +92,8 @@ static void check_hung_task(struct task_ * Ensure the task is not frozen. * Also, skip vfork and any other user process that freezer should skip. */ - if (unlikely(t->flags & (PF_FROZEN | PF_FREEZER_SKIP))) - return; + if (unlikely(t->state & (TASK_FREEZABLE | TASK_FROZEN))) + return; /* * When a freshly created task is scheduled once, changes its state to --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -23,7 +23,8 @@ void lock_system_sleep(void) { - current->flags |= PF_FREEZER_SKIP; + WARN_ON_ONCE(current->flags & PF_NOFREEZE); + current->flags |= PF_NOFREEZE; mutex_lock(&system_transition_mutex); } EXPORT_SYMBOL_GPL(lock_system_sleep); @@ -46,7 +47,7 @@ void unlock_system_sleep(void) * Which means, if we use try_to_freeze() here, it would make them * enter the refrigerator, thus causing hibernation to lockup. */ - current->flags &= ~PF_FREEZER_SKIP; + current->flags &= ~PF_NOFREEZE; mutex_unlock(&system_transition_mutex); } EXPORT_SYMBOL_GPL(unlock_system_sleep); --- a/kernel/power/process.c +++ b/kernel/power/process.c @@ -53,8 +53,7 @@ static int try_to_freeze_tasks(bool user if (p == current || !freeze_task(p)) continue; - if (!freezer_should_skip(p)) - todo++; + todo++; } read_unlock(&tasklist_lock); @@ -99,8 +98,7 @@ static int try_to_freeze_tasks(bool user if (!wakeup || pm_debug_messages_on) { read_lock(&tasklist_lock); for_each_process_thread(g, p) { - if (p != current && !freezer_should_skip(p) - && freezing(p) && !frozen(p)) + if (p != current && freezing(p) && !frozen(p)) sched_show_task(p); } read_unlock(&tasklist_lock); @@ -132,7 +130,7 @@ int freeze_processes(void) current->flags |= PF_SUSPEND_TASK; if (!pm_freezing) - atomic_inc(&system_freezing_cnt); + static_branch_inc(&freezer_active); pm_wakeup_clear(true); pr_info("Freezing user space processes ... "); @@ -193,7 +191,7 @@ void thaw_processes(void) trace_suspend_resume(TPS("thaw_processes"), 0, true); if (pm_freezing) - atomic_dec(&system_freezing_cnt); + static_branch_dec(&freezer_active); pm_freezing = false; pm_nosig_freezing = false; --- a/kernel/sched/completion.c +++ b/kernel/sched/completion.c @@ -139,6 +139,12 @@ void __sched wait_for_completion(struct } EXPORT_SYMBOL(wait_for_completion); +void __sched wait_for_completion_freezable(struct completion *x) +{ + wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_UNINTERRUPTIBLE|TASK_FREEZABLE); +} +EXPORT_SYMBOL(wait_for_completion_freezable); + /** * wait_for_completion_timeout: - waits for completion of a task (w/timeout) * @x: holds the state of this particular completion @@ -247,6 +253,16 @@ int __sched wait_for_completion_killable } EXPORT_SYMBOL(wait_for_completion_killable); +int __sched wait_for_completion_killable_freezable(struct completion *x) +{ + long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, + TASK_KILLABLE|TASK_FREEZABLE); + if (t == -ERESTARTSYS) + return t; + return 0; +} +EXPORT_SYMBOL(wait_for_completion_killable_freezable); + /** * wait_for_completion_killable_timeout: - waits for completion of a task (w/(to,killable)) * @x: holds the state of this particular completion --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -5897,7 +5897,7 @@ static void __sched notrace __schedule(b prev->sched_contributes_to_load = (prev_state & TASK_UNINTERRUPTIBLE) && !(prev_state & TASK_NOLOAD) && - !(prev->flags & PF_FROZEN); + !(prev_state & TASK_FROZEN); if (prev->sched_contributes_to_load) rq->nr_uninterruptible++; --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2265,7 +2265,7 @@ static void ptrace_stop(int exit_code, i read_unlock(&tasklist_lock); cgroup_enter_frozen(); preempt_enable_no_resched(); - freezable_schedule(); + schedule(); cgroup_leave_frozen(true); } else { /* @@ -2445,7 +2445,7 @@ static bool do_signal_stop(int signr) /* Now we don't run again until woken by SIGCONT or SIGKILL */ cgroup_enter_frozen(); - freezable_schedule(); + schedule(); return true; } else { /* @@ -2521,11 +2521,11 @@ static void do_freezer_trap(void) * immediately (if there is a non-fatal signal pending), and * put the task into sleep. */ - __set_current_state(TASK_INTERRUPTIBLE); + __set_current_state(TASK_INTERRUPTIBLE|TASK_FREEZABLE); clear_thread_flag(TIF_SIGPENDING); spin_unlock_irq(¤t->sighand->siglock); cgroup_enter_frozen(); - freezable_schedule(); + schedule(); } static int ptrace_signal(int signr, kernel_siginfo_t *info) @@ -3569,9 +3569,9 @@ static int do_sigtimedwait(const sigset_ recalc_sigpending(); spin_unlock_irq(&tsk->sighand->siglock); - __set_current_state(TASK_INTERRUPTIBLE); - ret = freezable_schedule_hrtimeout_range(to, tsk->timer_slack_ns, - HRTIMER_MODE_REL); + __set_current_state(TASK_INTERRUPTIBLE|TASK_FREEZABLE); + ret = schedule_hrtimeout_range(to, tsk->timer_slack_ns, + HRTIMER_MODE_REL); spin_lock_irq(&tsk->sighand->siglock); __set_task_blocked(tsk, &tsk->real_blocked); sigemptyset(&tsk->real_blocked); --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -1889,11 +1889,11 @@ static int __sched do_nanosleep(struct h struct restart_block *restart; do { - set_current_state(TASK_INTERRUPTIBLE); + set_current_state(TASK_INTERRUPTIBLE|TASK_FREEZABLE); hrtimer_sleeper_start_expires(t, mode); if (likely(t->task)) - freezable_schedule(); + schedule(); hrtimer_cancel(&t->timer); mode = HRTIMER_MODE_ABS; --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -794,8 +794,8 @@ static void khugepaged_alloc_sleep(void) DEFINE_WAIT(wait); add_wait_queue(&khugepaged_wait, &wait); - freezable_schedule_timeout_interruptible( - msecs_to_jiffies(khugepaged_alloc_sleep_millisecs)); + __set_current_state(TASK_INTERRUPTIBLE|TASK_FREEZABLE); + schedule_timeout(msecs_to_jiffies(khugepaged_alloc_sleep_millisecs)); remove_wait_queue(&khugepaged_wait, &wait); } --- a/net/sunrpc/sched.c +++ b/net/sunrpc/sched.c @@ -268,7 +268,7 @@ EXPORT_SYMBOL_GPL(rpc_destroy_wait_queue static int rpc_wait_bit_killable(struct wait_bit_key *key, int mode) { - freezable_schedule_unsafe(); + schedule(); if (signal_pending_state(mode, current)) return -ERESTARTSYS; return 0; @@ -324,14 +324,12 @@ static int rpc_complete_task(struct rpc_ * to enforce taking of the wq->lock and hence avoid races with * rpc_complete_task(). */ -int __rpc_wait_for_completion_task(struct rpc_task *task, wait_bit_action_f *action) +int rpc_wait_for_completion_task(struct rpc_task *task) { - if (action == NULL) - action = rpc_wait_bit_killable; return out_of_line_wait_on_bit(&task->tk_runstate, RPC_TASK_ACTIVE, - action, TASK_KILLABLE); + rpc_wait_bit_killable, TASK_KILLABLE|TASK_FREEZABLE_UNSAFE); } -EXPORT_SYMBOL_GPL(__rpc_wait_for_completion_task); +EXPORT_SYMBOL_GPL(rpc_wait_for_completion_task); /* * Make an RPC task runnable. @@ -928,7 +926,7 @@ static void __rpc_execute(struct rpc_tas trace_rpc_task_sync_sleep(task, task->tk_action); status = out_of_line_wait_on_bit(&task->tk_runstate, RPC_TASK_QUEUED, rpc_wait_bit_killable, - TASK_KILLABLE); + TASK_KILLABLE|TASK_FREEZABLE); if (status < 0) { /* * When a sync task receives a signal, it exits with --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -2190,13 +2190,14 @@ static long unix_stream_data_wait(struct struct sk_buff *last, unsigned int last_len, bool freezable) { + unsigned int state = TASK_INTERRUPTIBLE | freezable * TASK_FREEZABLE; struct sk_buff *tail; DEFINE_WAIT(wait); unix_state_lock(sk); for (;;) { - prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); + prepare_to_wait(sk_sleep(sk), &wait, state); tail = skb_peek_tail(&sk->sk_receive_queue); if (tail != last || @@ -2209,10 +2210,7 @@ static long unix_stream_data_wait(struct sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk); unix_state_unlock(sk); - if (freezable) - timeo = freezable_schedule_timeout(timeo); - else - timeo = schedule_timeout(timeo); + timeo = schedule_timeout(timeo); unix_state_lock(sk); if (sock_flag(sk, SOCK_DEAD))