From: Christoph Lameter Date: Sat, 25 Jun 2005 06:13:50 +0000 (-0700) Subject: [PATCH] Cleanup patch for process freezing X-Git-Tag: v2.6.13-rc1~68^2~7^2 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3e1d1d28d99dabe63c64f7f40f1ca1d646de1f73;p=linux-2.6 [PATCH] Cleanup patch for process freezing 1. Establish a simple API for process freezing defined in linux/include/sched.h: frozen(process) Check for frozen process freezing(process) Check if a process is being frozen freeze(process) Tell a process to freeze (go to refrigerator) thaw_process(process) Restart process frozen_process(process) Process is frozen now 2. Remove all references to PF_FREEZE and PF_FROZEN from all kernel sources except sched.h 3. Fix numerous locations where try_to_freeze is manually done by a driver 4. Remove the argument that is no longer necessary from two function calls. 5. Some whitespace cleanup 6. Clear potential race in refrigerator (provides an open window of PF_FREEZE cleared before setting PF_FROZEN, recalc_sigpending does not check PF_FROZEN). This patch does not address the problem of freeze_processes() violating the rule that a task may only modify its own flags by setting PF_FREEZE. This is not clean in an SMP environment. freeze(process) is therefore not SMP safe! Signed-off-by: Christoph Lameter Signed-off-by: Linus Torvalds --- diff --git a/Documentation/power/kernel_threads.txt b/Documentation/power/kernel_threads.txt index 60b548105e..fb57784986 100644 --- a/Documentation/power/kernel_threads.txt +++ b/Documentation/power/kernel_threads.txt @@ -12,8 +12,7 @@ refrigerator. Code to do this looks like this: do { hub_events(); wait_event_interruptible(khubd_wait, !list_empty(&hub_event_list)); - if (current->flags & PF_FREEZE) - refrigerator(PF_FREEZE); + try_to_freeze(); } while (!signal_pending(current)); from drivers/usb/core/hub.c::hub_thread() diff --git a/Documentation/power/swsusp.txt b/Documentation/power/swsusp.txt index c7c3459fde..4e1627cc5b 100644 --- a/Documentation/power/swsusp.txt +++ b/Documentation/power/swsusp.txt @@ -164,8 +164,7 @@ place where the thread is safe to be frozen (no kernel semaphores should be held at that point and it must be safe to sleep there), and add: - if (current->flags & PF_FREEZE) - refrigerator(PF_FREEZE); + try_to_freeze(); If the thread is needed for writing the image to storage, you should instead set the PF_NOFREEZE process flag when creating the thread. diff --git a/arch/frv/kernel/signal.c b/arch/frv/kernel/signal.c index d8d8f3d430..36a2dffc8e 100644 --- a/arch/frv/kernel/signal.c +++ b/arch/frv/kernel/signal.c @@ -536,10 +536,8 @@ int do_signal(struct pt_regs *regs, sigset_t *oldset) if (!user_mode(regs)) return 1; - if (current->flags & PF_FREEZE) { - refrigerator(0); + if (try_to_freeze()) goto no_signal; - } if (!oldset) oldset = ¤t->blocked; diff --git a/arch/h8300/kernel/signal.c b/arch/h8300/kernel/signal.c index a4799d633e..5aab87eae1 100644 --- a/arch/h8300/kernel/signal.c +++ b/arch/h8300/kernel/signal.c @@ -517,10 +517,8 @@ asmlinkage int do_signal(struct pt_regs *regs, sigset_t *oldset) if ((regs->ccr & 0x10)) return 1; - if (current->flags & PF_FREEZE) { - refrigerator(0); + if (try_to_freeze()) goto no_signal; - } current->thread.esp0 = (unsigned long) regs; diff --git a/arch/i386/kernel/io_apic.c b/arch/i386/kernel/io_apic.c index 08540bc4ba..2451a3a994 100644 --- a/arch/i386/kernel/io_apic.c +++ b/arch/i386/kernel/io_apic.c @@ -573,7 +573,7 @@ static int balanced_irq(void *unused) for ( ; ; ) { set_current_state(TASK_INTERRUPTIBLE); time_remaining = schedule_timeout(time_remaining); - try_to_freeze(PF_FREEZE); + try_to_freeze(); if (time_after(jiffies, prev_balance_time+balanced_irq_interval)) { do_irq_balance(); diff --git a/arch/i386/kernel/signal.c b/arch/i386/kernel/signal.c index b9b8f4e20f..ac5b1e975c 100644 --- a/arch/i386/kernel/signal.c +++ b/arch/i386/kernel/signal.c @@ -608,10 +608,8 @@ int fastcall do_signal(struct pt_regs *regs, sigset_t *oldset) if (!user_mode(regs)) return 1; - if (current->flags & PF_FREEZE) { - refrigerator(0); + if (try_to_freeze) goto no_signal; - } if (!oldset) oldset = ¤t->blocked; diff --git a/arch/m32r/kernel/signal.c b/arch/m32r/kernel/signal.c index 50311eb07a..5aef7e406e 100644 --- a/arch/m32r/kernel/signal.c +++ b/arch/m32r/kernel/signal.c @@ -371,10 +371,8 @@ int do_signal(struct pt_regs *regs, sigset_t *oldset) if (!user_mode(regs)) return 1; - if (current->flags & PF_FREEZE) { - refrigerator(0); + if (try_to_freeze()) goto no_signal; - } if (!oldset) oldset = ¤t->blocked; diff --git a/arch/ppc/kernel/signal.c b/arch/ppc/kernel/signal.c index 7c8437da09..8aaeb6f4e7 100644 --- a/arch/ppc/kernel/signal.c +++ b/arch/ppc/kernel/signal.c @@ -705,8 +705,7 @@ int do_signal(sigset_t *oldset, struct pt_regs *regs) unsigned long frame, newsp; int signr, ret; - if (current->flags & PF_FREEZE) { - refrigerator(PF_FREEZE); + if (try_to_freeze()) { signr = 0; if (!signal_pending(current)) goto no_signal; diff --git a/arch/x86_64/kernel/signal.c b/arch/x86_64/kernel/signal.c index 98b7ba95d5..98590a989f 100644 --- a/arch/x86_64/kernel/signal.c +++ b/arch/x86_64/kernel/signal.c @@ -425,7 +425,7 @@ int do_signal(struct pt_regs *regs, sigset_t *oldset) if (!user_mode(regs)) return 1; - if (try_to_freeze(0)) + if (try_to_freeze()) goto no_signal; if (!oldset) diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c index 7f3d78de26..7b838342f0 100644 --- a/drivers/block/pktcdvd.c +++ b/drivers/block/pktcdvd.c @@ -1251,8 +1251,7 @@ static int kcdrwd(void *foobar) VPRINTK("kcdrwd: wake up\n"); /* make swsusp happy with our thread */ - if (current->flags & PF_FREEZE) - refrigerator(PF_FREEZE); + try_to_freeze(); list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) { if (!pkt->sleep_time) diff --git a/drivers/ieee1394/ieee1394_core.c b/drivers/ieee1394/ieee1394_core.c index 2d9a9b74e6..629070b83a 100644 --- a/drivers/ieee1394/ieee1394_core.c +++ b/drivers/ieee1394/ieee1394_core.c @@ -1041,10 +1041,8 @@ static int hpsbpkt_thread(void *__hi) while (1) { if (down_interruptible(&khpsbpkt_sig)) { - if (current->flags & PF_FREEZE) { - refrigerator(0); + if (try_to_freeze()) continue; - } printk("khpsbpkt: received unexpected signal?!\n" ); break; } diff --git a/drivers/ieee1394/nodemgr.c b/drivers/ieee1394/nodemgr.c index 32abb6dda8..9a46c3b44b 100644 --- a/drivers/ieee1394/nodemgr.c +++ b/drivers/ieee1394/nodemgr.c @@ -1510,7 +1510,7 @@ static int nodemgr_host_thread(void *__hi) if (down_interruptible(&hi->reset_sem) || down_interruptible(&nodemgr_serialize)) { - if (try_to_freeze(PF_FREEZE)) + if (try_to_freeze()) continue; printk("NodeMgr: received unexpected signal?!\n" ); break; diff --git a/drivers/input/gameport/gameport.c b/drivers/input/gameport/gameport.c index e152d0fa0c..c77a82e460 100644 --- a/drivers/input/gameport/gameport.c +++ b/drivers/input/gameport/gameport.c @@ -439,7 +439,7 @@ static int gameport_thread(void *nothing) do { gameport_handle_events(); wait_event_interruptible(gameport_wait, !list_empty(&gameport_event_list)); - try_to_freeze(PF_FREEZE); + try_to_freeze(); } while (!signal_pending(current)); printk(KERN_DEBUG "gameport: kgameportd exiting\n"); diff --git a/drivers/input/serio/serio.c b/drivers/input/serio/serio.c index feab497040..341824c485 100644 --- a/drivers/input/serio/serio.c +++ b/drivers/input/serio/serio.c @@ -344,7 +344,7 @@ static int serio_thread(void *nothing) do { serio_handle_events(); wait_event_interruptible(serio_wait, !list_empty(&serio_event_list)); - try_to_freeze(PF_FREEZE); + try_to_freeze(); } while (!signal_pending(current)); printk(KERN_DEBUG "serio: kseriod exiting\n"); diff --git a/drivers/macintosh/therm_adt746x.c b/drivers/macintosh/therm_adt746x.c index 5ba190ce14..c9ca1118e4 100644 --- a/drivers/macintosh/therm_adt746x.c +++ b/drivers/macintosh/therm_adt746x.c @@ -328,9 +328,7 @@ static int monitor_task(void *arg) struct thermostat* th = arg; while(!kthread_should_stop()) { - if (current->flags & PF_FREEZE) - refrigerator(PF_FREEZE); - + try_to_freeze(); msleep_interruptible(2000); #ifndef DEBUG diff --git a/drivers/md/md.c b/drivers/md/md.c index 0c6b5b6baf..3802f7a17f 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -2976,8 +2976,7 @@ static int md_thread(void * arg) wait_event_interruptible_timeout(thread->wqueue, test_bit(THREAD_WAKEUP, &thread->flags), thread->timeout); - if (current->flags & PF_FREEZE) - refrigerator(PF_FREEZE); + try_to_freeze(); clear_bit(THREAD_WAKEUP, &thread->flags); diff --git a/drivers/media/dvb/dvb-core/dvb_frontend.c b/drivers/media/dvb/dvb-core/dvb_frontend.c index d6b7a9de47..f11daae91c 100644 --- a/drivers/media/dvb/dvb-core/dvb_frontend.c +++ b/drivers/media/dvb/dvb-core/dvb_frontend.c @@ -391,8 +391,7 @@ static int dvb_frontend_thread(void *data) break; } - if (current->flags & PF_FREEZE) - refrigerator(PF_FREEZE); + try_to_freeze(); if (down_interruptible(&fepriv->sem)) break; diff --git a/drivers/media/video/msp3400.c b/drivers/media/video/msp3400.c index 1b7d38e96f..b4ee9dfe6d 100644 --- a/drivers/media/video/msp3400.c +++ b/drivers/media/video/msp3400.c @@ -750,8 +750,7 @@ static int msp34xx_sleep(struct msp3400c *msp, int timeout) #endif } } - if (current->flags & PF_FREEZE) - refrigerator(PF_FREEZE); + try_to_freeze(); remove_wait_queue(&msp->wq, &wait); return msp->restart; } diff --git a/drivers/media/video/video-buf-dvb.c b/drivers/media/video/video-buf-dvb.c index 5f870075b5..15f5bb4869 100644 --- a/drivers/media/video/video-buf-dvb.c +++ b/drivers/media/video/video-buf-dvb.c @@ -62,8 +62,7 @@ static int videobuf_dvb_thread(void *data) break; if (kthread_should_stop()) break; - if (current->flags & PF_FREEZE) - refrigerator(PF_FREEZE); + try_to_freeze(); /* feed buffer data to demux */ if (buf->state == STATE_DONE) diff --git a/drivers/net/8139too.c b/drivers/net/8139too.c index 047202c4d9..5a4a08a7c9 100644 --- a/drivers/net/8139too.c +++ b/drivers/net/8139too.c @@ -1606,7 +1606,7 @@ static int rtl8139_thread (void *data) do { timeout = interruptible_sleep_on_timeout (&tp->thr_wait, timeout); /* make swsusp happy with our thread */ - try_to_freeze(PF_FREEZE); + try_to_freeze(); } while (!signal_pending (current) && (timeout > 0)); if (signal_pending (current)) { diff --git a/drivers/net/irda/sir_kthread.c b/drivers/net/irda/sir_kthread.c index 18cea10995..c65054364b 100644 --- a/drivers/net/irda/sir_kthread.c +++ b/drivers/net/irda/sir_kthread.c @@ -135,8 +135,7 @@ static int irda_thread(void *startup) remove_wait_queue(&irda_rq_queue.kick, &wait); /* make swsusp happy with our thread */ - if (current->flags & PF_FREEZE) - refrigerator(PF_FREEZE); + try_to_freeze(); run_irda_queue(); } diff --git a/drivers/net/irda/stir4200.c b/drivers/net/irda/stir4200.c index 66f488c137..15f207323d 100644 --- a/drivers/net/irda/stir4200.c +++ b/drivers/net/irda/stir4200.c @@ -763,7 +763,7 @@ static int stir_transmit_thread(void *arg) { #ifdef CONFIG_PM /* if suspending, then power off and wait */ - if (unlikely(current->flags & PF_FREEZE)) { + if (unlikely(freezing(current))) { if (stir->receiving) receive_stop(stir); else @@ -771,7 +771,7 @@ static int stir_transmit_thread(void *arg) write_reg(stir, REG_CTRL1, CTRL1_TXPWD|CTRL1_RXPWD); - refrigerator(PF_FREEZE); + refrigerator(); if (change_speed(stir, stir->speed)) break; diff --git a/drivers/net/wireless/airo.c b/drivers/net/wireless/airo.c index fb10a2db63..d72e0385e4 100644 --- a/drivers/net/wireless/airo.c +++ b/drivers/net/wireless/airo.c @@ -2918,7 +2918,7 @@ static int airo_thread(void *data) { flush_signals(current); /* make swsusp happy with our thread */ - try_to_freeze(PF_FREEZE); + try_to_freeze(); if (test_bit(JOB_DIE, &ai->flags)) break; diff --git a/drivers/pcmcia/cs.c b/drivers/pcmcia/cs.c index d136b3c8fa..48e4f04530 100644 --- a/drivers/pcmcia/cs.c +++ b/drivers/pcmcia/cs.c @@ -718,7 +718,7 @@ static int pccardd(void *__skt) } schedule(); - try_to_freeze(PF_FREEZE); + try_to_freeze(); if (!skt->thread) break; diff --git a/drivers/pnp/pnpbios/core.c b/drivers/pnp/pnpbios/core.c index e939c93a93..778a324028 100644 --- a/drivers/pnp/pnpbios/core.c +++ b/drivers/pnp/pnpbios/core.c @@ -182,7 +182,7 @@ static int pnp_dock_thread(void * unused) msleep_interruptible(2000); if(signal_pending(current)) { - if (try_to_freeze(PF_FREEZE)) + if (try_to_freeze()) continue; break; } diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index d2d648ee86..a8d879a85d 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -2808,7 +2808,7 @@ static int hub_thread(void *__unused) do { hub_events(); wait_event_interruptible(khubd_wait, !list_empty(&hub_event_list)); - try_to_freeze(PF_FREEZE); + try_to_freeze(); } while (!signal_pending(current)); pr_debug ("%s: khubd exiting\n", usbcore_name); diff --git a/drivers/usb/gadget/file_storage.c b/drivers/usb/gadget/file_storage.c index 037a7f1638..a9be85103d 100644 --- a/drivers/usb/gadget/file_storage.c +++ b/drivers/usb/gadget/file_storage.c @@ -1554,8 +1554,7 @@ static int sleep_thread(struct fsg_dev *fsg) rc = wait_event_interruptible(fsg->thread_wqh, fsg->thread_wakeup_needed); fsg->thread_wakeup_needed = 0; - if (current->flags & PF_FREEZE) - refrigerator(PF_FREEZE); + try_to_freeze(); return (rc ? -EINTR : 0); } diff --git a/drivers/usb/storage/usb.c b/drivers/usb/storage/usb.c index 35c1ca6b5a..77e7fc258a 100644 --- a/drivers/usb/storage/usb.c +++ b/drivers/usb/storage/usb.c @@ -847,10 +847,8 @@ retry: wait_event_interruptible_timeout(us->delay_wait, test_bit(US_FLIDX_DISCONNECTING, &us->flags), delay_use * HZ); - if (current->flags & PF_FREEZE) { - refrigerator(PF_FREEZE); + if (try_to_freeze()) goto retry; - } } /* If the device is still connected, perform the scanning */ diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c index b460927ec3..312cf3220f 100644 --- a/drivers/w1/w1.c +++ b/drivers/w1/w1.c @@ -646,7 +646,7 @@ static int w1_control(void *data) while (!control_needs_exit || have_to_wait) { have_to_wait = 0; - try_to_freeze(PF_FREEZE); + try_to_freeze(); msleep_interruptible(w1_timeout * 1000); if (signal_pending(current)) @@ -725,7 +725,7 @@ int w1_process(void *data) allow_signal(SIGTERM); while (!test_bit(W1_MASTER_NEED_EXIT, &dev->flags)) { - try_to_freeze(PF_FREEZE); + try_to_freeze(); msleep_interruptible(w1_timeout * 1000); if (signal_pending(current)) diff --git a/fs/afs/kafsasyncd.c b/fs/afs/kafsasyncd.c index 6fc88ae8ad..7ac07d0d47 100644 --- a/fs/afs/kafsasyncd.c +++ b/fs/afs/kafsasyncd.c @@ -116,7 +116,7 @@ static int kafsasyncd(void *arg) remove_wait_queue(&kafsasyncd_sleepq, &myself); set_current_state(TASK_RUNNING); - try_to_freeze(PF_FREEZE); + try_to_freeze(); /* discard pending signals */ afs_discard_my_signals(); diff --git a/fs/afs/kafstimod.c b/fs/afs/kafstimod.c index 86e710dd05..65bc05ab81 100644 --- a/fs/afs/kafstimod.c +++ b/fs/afs/kafstimod.c @@ -91,7 +91,7 @@ static int kafstimod(void *arg) complete_and_exit(&kafstimod_dead, 0); } - try_to_freeze(PF_FREEZE); + try_to_freeze(); /* discard pending signals */ afs_discard_my_signals(); diff --git a/fs/jbd/journal.c b/fs/jbd/journal.c index 1e6f2e2ad4..5e7b439495 100644 --- a/fs/jbd/journal.c +++ b/fs/jbd/journal.c @@ -167,7 +167,7 @@ loop: } wake_up(&journal->j_wait_done_commit); - if (current->flags & PF_FREEZE) { + if (freezing(current)) { /* * The simpler the better. Flushing journal isn't a * good idea, because that depends on threads that may @@ -175,7 +175,7 @@ loop: */ jbd_debug(1, "Now suspending kjournald\n"); spin_unlock(&journal->j_state_lock); - refrigerator(PF_FREEZE); + refrigerator(); spin_lock(&journal->j_state_lock); } else { /* diff --git a/fs/jfs/jfs_logmgr.c b/fs/jfs/jfs_logmgr.c index 7c8387ed41..79d07624bf 100644 --- a/fs/jfs/jfs_logmgr.c +++ b/fs/jfs/jfs_logmgr.c @@ -2359,9 +2359,9 @@ int jfsIOWait(void *arg) lbmStartIO(bp); spin_lock_irq(&log_redrive_lock); } - if (current->flags & PF_FREEZE) { + if (freezing(current)) { spin_unlock_irq(&log_redrive_lock); - refrigerator(PF_FREEZE); + refrigerator(); } else { add_wait_queue(&jfs_IO_thread_wait, &wq); set_current_state(TASK_INTERRUPTIBLE); diff --git a/fs/jfs/jfs_txnmgr.c b/fs/jfs/jfs_txnmgr.c index 8cbaaff1d5..121c981ff4 100644 --- a/fs/jfs/jfs_txnmgr.c +++ b/fs/jfs/jfs_txnmgr.c @@ -2788,9 +2788,9 @@ int jfs_lazycommit(void *arg) /* In case a wakeup came while all threads were active */ jfs_commit_thread_waking = 0; - if (current->flags & PF_FREEZE) { + if (freezing(current)) { LAZY_UNLOCK(flags); - refrigerator(PF_FREEZE); + refrigerator(); } else { DECLARE_WAITQUEUE(wq, current); @@ -2987,9 +2987,9 @@ int jfs_sync(void *arg) /* Add anon_list2 back to anon_list */ list_splice_init(&TxAnchor.anon_list2, &TxAnchor.anon_list); - if (current->flags & PF_FREEZE) { + if (freezing(current)) { TXN_UNLOCK(); - refrigerator(PF_FREEZE); + refrigerator(); } else { DECLARE_WAITQUEUE(wq, current); diff --git a/fs/lockd/clntproc.c b/fs/lockd/clntproc.c index fd77ed1d71..14b3ce87fa 100644 --- a/fs/lockd/clntproc.c +++ b/fs/lockd/clntproc.c @@ -313,7 +313,7 @@ static int nlm_wait_on_grace(wait_queue_head_t *queue) prepare_to_wait(queue, &wait, TASK_INTERRUPTIBLE); if (!signalled ()) { schedule_timeout(NLMCLNT_GRACE_WAIT); - try_to_freeze(PF_FREEZE); + try_to_freeze(); if (!signalled ()) status = 0; } diff --git a/fs/xfs/linux-2.6/xfs_buf.c b/fs/xfs/linux-2.6/xfs_buf.c index c60e69431e..df0cba239d 100644 --- a/fs/xfs/linux-2.6/xfs_buf.c +++ b/fs/xfs/linux-2.6/xfs_buf.c @@ -1771,9 +1771,9 @@ xfsbufd( INIT_LIST_HEAD(&tmp); do { - if (unlikely(current->flags & PF_FREEZE)) { + if (unlikely(freezing(current))) { xfsbufd_force_sleep = 1; - refrigerator(PF_FREEZE); + refrigerator(); } else { xfsbufd_force_sleep = 0; } diff --git a/fs/xfs/linux-2.6/xfs_super.c b/fs/xfs/linux-2.6/xfs_super.c index 5fe9af38aa..f6dd7de259 100644 --- a/fs/xfs/linux-2.6/xfs_super.c +++ b/fs/xfs/linux-2.6/xfs_super.c @@ -483,7 +483,7 @@ xfssyncd( set_current_state(TASK_INTERRUPTIBLE); timeleft = schedule_timeout(timeleft); /* swsusp */ - try_to_freeze(PF_FREEZE); + try_to_freeze(); if (vfsp->vfs_flag & VFS_UMOUNT) break; diff --git a/include/linux/sched.h b/include/linux/sched.h index 2c69682b04..e7fd09b055 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1245,33 +1245,78 @@ extern void normalize_rt_tasks(void); #endif -/* try_to_freeze - * - * Checks whether we need to enter the refrigerator - * and returns 1 if we did so. - */ #ifdef CONFIG_PM -extern void refrigerator(unsigned long); +/* + * Check if a process has been frozen + */ +static inline int frozen(struct task_struct *p) +{ + return p->flags & PF_FROZEN; +} + +/* + * Check if there is a request to freeze a process + */ +static inline int freezing(struct task_struct *p) +{ + return p->flags & PF_FREEZE; +} + +/* + * Request that a process be frozen + * FIXME: SMP problem. We may not modify other process' flags! + */ +static inline void freeze(struct task_struct *p) +{ + p->flags |= PF_FREEZE; +} + +/* + * Wake up a frozen process + */ +static inline int thaw_process(struct task_struct *p) +{ + if (frozen(p)) { + p->flags &= ~PF_FROZEN; + wake_up_process(p); + return 1; + } + return 0; +} + +/* + * freezing is complete, mark process as frozen + */ +static inline void frozen_process(struct task_struct *p) +{ + p->flags = (p->flags & ~PF_FREEZE) | PF_FROZEN; +} + +extern void refrigerator(void); extern int freeze_processes(void); extern void thaw_processes(void); -static inline int try_to_freeze(unsigned long refrigerator_flags) +static inline int try_to_freeze(void) { - if (unlikely(current->flags & PF_FREEZE)) { - refrigerator(refrigerator_flags); + if (freezing(current)) { + refrigerator(); return 1; } else return 0; } #else -static inline void refrigerator(unsigned long flag) {} +static inline int frozen(struct task_struct *p) { return 0; } +static inline int freezing(struct task_struct *p) { return 0; } +static inline void freeze(struct task_struct *p) { BUG(); } +static inline int thaw_process(struct task_struct *p) { return 1; } +static inline void frozen_process(struct task_struct *p) { BUG(); } + +static inline void refrigerator(void) {} static inline int freeze_processes(void) { BUG(); return 0; } static inline void thaw_processes(void) {} -static inline int try_to_freeze(unsigned long refrigerator_flags) -{ - return 0; -} +static inline int try_to_freeze(void) { return 0; } + #endif /* CONFIG_PM */ #endif /* __KERNEL__ */ diff --git a/kernel/power/process.c b/kernel/power/process.c index 78d92dc6a1..0a086640bc 100644 --- a/kernel/power/process.c +++ b/kernel/power/process.c @@ -32,7 +32,7 @@ static inline int freezeable(struct task_struct * p) } /* Refrigerator is place where frozen processes are stored :-). */ -void refrigerator(unsigned long flag) +void refrigerator(void) { /* Hmm, should we be allowed to suspend when there are realtime processes around? */ @@ -41,14 +41,13 @@ void refrigerator(unsigned long flag) current->state = TASK_UNINTERRUPTIBLE; pr_debug("%s entered refrigerator\n", current->comm); printk("="); - current->flags &= ~PF_FREEZE; + frozen_process(current); spin_lock_irq(¤t->sighand->siglock); recalc_sigpending(); /* We sent fake signal, clean it up */ spin_unlock_irq(¤t->sighand->siglock); - current->flags |= PF_FROZEN; - while (current->flags & PF_FROZEN) + while (frozen(current)) schedule(); pr_debug("%s left refrigerator\n", current->comm); current->state = save; @@ -57,10 +56,10 @@ void refrigerator(unsigned long flag) /* 0 = success, else # of processes that we failed to stop */ int freeze_processes(void) { - int todo; - unsigned long start_time; + int todo; + unsigned long start_time; struct task_struct *g, *p; - + printk( "Stopping tasks: " ); start_time = jiffies; do { @@ -70,14 +69,12 @@ int freeze_processes(void) unsigned long flags; if (!freezeable(p)) continue; - if ((p->flags & PF_FROZEN) || + if ((frozen(p)) || (p->state == TASK_TRACED) || (p->state == TASK_STOPPED)) continue; - /* FIXME: smp problem here: we may not access other process' flags - without locking */ - p->flags |= PF_FREEZE; + freeze(p); spin_lock_irqsave(&p->sighand->siglock, flags); signal_wake_up(p, 0); spin_unlock_irqrestore(&p->sighand->siglock, flags); @@ -91,7 +88,7 @@ int freeze_processes(void) return todo; } } while(todo); - + printk( "|\n" ); BUG_ON(in_atomic()); return 0; @@ -106,10 +103,7 @@ void thaw_processes(void) do_each_thread(g, p) { if (!freezeable(p)) continue; - if (p->flags & PF_FROZEN) { - p->flags &= ~PF_FROZEN; - wake_up_process(p); - } else + if (!thaw_process(p)) printk(KERN_INFO " Strange, %s not stopped\n", p->comm ); } while_each_thread(g, p); diff --git a/kernel/sched.c b/kernel/sched.c index 76080d142e..6fa9ea4ae4 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -4174,8 +4174,7 @@ static int migration_thread(void * data) struct list_head *head; migration_req_t *req; - if (current->flags & PF_FREEZE) - refrigerator(PF_FREEZE); + try_to_freeze(); spin_lock_irq(&rq->lock); diff --git a/kernel/signal.c b/kernel/signal.c index d1258729a5..ca1186eef9 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -213,7 +213,7 @@ static inline int has_pending_signals(sigset_t *signal, sigset_t *blocked) fastcall void recalc_sigpending_tsk(struct task_struct *t) { if (t->signal->group_stop_count > 0 || - (t->flags & PF_FREEZE) || + (freezing(t)) || PENDING(&t->pending, &t->blocked) || PENDING(&t->signal->shared_pending, &t->blocked)) set_tsk_thread_flag(t, TIF_SIGPENDING); @@ -2231,8 +2231,7 @@ sys_rt_sigtimedwait(const sigset_t __user *uthese, current->state = TASK_INTERRUPTIBLE; timeout = schedule_timeout(timeout); - if (current->flags & PF_FREEZE) - refrigerator(PF_FREEZE); + try_to_freeze(); spin_lock_irq(¤t->sighand->siglock); sig = dequeue_signal(current, &these, &info); current->blocked = current->real_blocked; diff --git a/mm/pdflush.c b/mm/pdflush.c index 38ce279cc8..d678195126 100644 --- a/mm/pdflush.c +++ b/mm/pdflush.c @@ -105,7 +105,7 @@ static int __pdflush(struct pdflush_work *my_work) spin_unlock_irq(&pdflush_lock); schedule(); - if (try_to_freeze(PF_FREEZE)) { + if (try_to_freeze()) { spin_lock_irq(&pdflush_lock); continue; } diff --git a/mm/vmscan.c b/mm/vmscan.c index 4b8e62a193..1fa312a8db 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1216,8 +1216,8 @@ static int kswapd(void *p) order = 0; for ( ; ; ) { unsigned long new_order; - if (current->flags & PF_FREEZE) - refrigerator(PF_FREEZE); + + try_to_freeze(); prepare_to_wait(&pgdat->kswapd_wait, &wait, TASK_INTERRUPTIBLE); new_order = pgdat->kswapd_max_order; diff --git a/net/rxrpc/krxiod.c b/net/rxrpc/krxiod.c index 2b537f425a..dada34a77b 100644 --- a/net/rxrpc/krxiod.c +++ b/net/rxrpc/krxiod.c @@ -138,7 +138,7 @@ static int rxrpc_krxiod(void *arg) _debug("### End Work"); - try_to_freeze(PF_FREEZE); + try_to_freeze(); /* discard pending signals */ rxrpc_discard_my_signals(); diff --git a/net/rxrpc/krxsecd.c b/net/rxrpc/krxsecd.c index 6020c89d92..1aadd026d3 100644 --- a/net/rxrpc/krxsecd.c +++ b/net/rxrpc/krxsecd.c @@ -107,7 +107,7 @@ static int rxrpc_krxsecd(void *arg) _debug("### End Inbound Calls"); - try_to_freeze(PF_FREEZE); + try_to_freeze(); /* discard pending signals */ rxrpc_discard_my_signals(); diff --git a/net/rxrpc/krxtimod.c b/net/rxrpc/krxtimod.c index 249c2b0290..3ac81cdd12 100644 --- a/net/rxrpc/krxtimod.c +++ b/net/rxrpc/krxtimod.c @@ -90,7 +90,7 @@ static int krxtimod(void *arg) complete_and_exit(&krxtimod_dead, 0); } - try_to_freeze(PF_FREEZE); + try_to_freeze(); /* discard pending signals */ rxrpc_discard_my_signals(); diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c index 05907035bc..56db8f13e6 100644 --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -1185,8 +1185,8 @@ svc_recv(struct svc_serv *serv, struct svc_rqst *rqstp, long timeout) arg->page_len = (pages-2)*PAGE_SIZE; arg->len = (pages-1)*PAGE_SIZE; arg->tail[0].iov_len = 0; - - try_to_freeze(PF_FREEZE); + + try_to_freeze(); if (signalled()) return -EINTR; @@ -1227,7 +1227,7 @@ svc_recv(struct svc_serv *serv, struct svc_rqst *rqstp, long timeout) schedule_timeout(timeout); - try_to_freeze(PF_FREEZE); + try_to_freeze(); spin_lock_bh(&serv->sv_lock); remove_wait_queue(&rqstp->rq_wait, &wait);