linux/drivers/char
Rafael J. Wysocki 8314418629 Freezer: make kernel threads nonfreezable by default
Currently, the freezer treats all tasks as freezable, except for the kernel
threads that explicitly set the PF_NOFREEZE flag for themselves.  This
approach is problematic, since it requires every kernel thread to either
set PF_NOFREEZE explicitly, or call try_to_freeze(), even if it doesn't
care for the freezing of tasks at all.

It seems better to only require the kernel threads that want to or need to
be frozen to use some freezer-related code and to remove any
freezer-related code from the other (nonfreezable) kernel threads, which is
done in this patch.

The patch causes all kernel threads to be nonfreezable by default (ie.  to
have PF_NOFREEZE set by default) and introduces the set_freezable()
function that should be called by the freezable kernel threads in order to
unset PF_NOFREEZE.  It also makes all of the currently freezable kernel
threads call set_freezable(), so it shouldn't cause any (intentional)
change of behaviour to appear.  Additionally, it updates documentation to
describe the freezing of tasks more accurately.

[akpm@linux-foundation.org: build fixes]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Nigel Cunningham <nigel@nigel.suspend2.net>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-17 10:23:02 -07:00
..
agp Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/agpgart 2007-07-12 13:41:54 -07:00
drm drm: add idr_init to drm_stub.c 2007-07-17 14:20:07 +10:00
hw_random intel-rng: undo mess made by an 80 column extremist 2007-07-16 09:05:46 -07:00
ip2 Char: ip2, use msleep for sleeping 2007-07-16 09:05:44 -07:00
ipmi drivers/char/ipmi/ipmi_si_intf.c: lower printk severity 2007-07-16 09:05:52 -07:00
mwave [PATCH] mwave: interesting flags savings 2007-02-20 17:10:14 -08:00
pcmcia Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial 2007-05-09 12:54:17 -07:00
rio Overrun in drivers/char/rio/riocmd.c 2007-05-11 08:29:34 -07:00
tpm Use menuconfig objects II - TPM 2007-07-16 09:05:40 -07:00
watchdog Merge git://git.kernel.org/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog 2007-06-03 12:36:56 -07:00
.gitignore
ChangeLog
Kconfig undeprecate raw driver 2007-07-16 09:05:46 -07:00
Makefile Audit: add TTY input auditing 2007-07-16 09:05:47 -07:00
amiserial.c amiserial: remove incorrect 'no termios change' check 2007-07-16 09:05:51 -07:00
apm-emulation.c Freezer: make kernel threads nonfreezable by default 2007-07-17 10:23:02 -07:00
applicom.c
applicom.h
briq_panel.c [POWERPC] Remove dead code for preventing pread() and pwrite() calls 2007-07-10 22:03:26 +10:00
cd1865.h
consolemap.c Kernel utf-8 handling 2007-07-16 09:05:46 -07:00
cp437.uni
cs5535_gpio.c Char: cs5535_gpio, add MODULE_DEVICE_TABLE 2007-05-08 11:15:04 -07:00
cyclades.c serial: remove termios checks from various old char serial drivers 2007-07-16 09:05:52 -07:00
decserial.c [PATCH] dz: Fixes to make it work 2006-12-07 08:39:41 -08:00
defkeymap.c_shipped
defkeymap.map
digi1.h
digiFep1.h
digiPCI.h
ds1286.c [CHAR] ds1286: Fix handling of seconds in RTC_ALM_SET ioctl. 2007-03-08 01:10:30 +00:00
ds1302.c [PATCH] DS1302: local_irq_disable() is redundant after local_irq_save() 2007-02-12 09:48:30 -08:00
ds1620.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
dsp56k.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
dtlk.c dtlk: fix error checks in module_init() 2007-05-08 11:15:09 -07:00
ec3104_keyb.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
efirtc.c
epca.c drivers/char: use __set_current_state() 2007-05-08 11:15:13 -07:00
epca.h
epcaconfig.h
esp.c serial: remove termios checks from various old char serial drivers 2007-07-16 09:05:52 -07:00
generic_nvram.c [PATCH] mark struct file_operations const 3 2007-02-12 09:48:45 -08:00
generic_serial.c genericserial: remove bogus optimisation check and dead code paths 2007-07-16 09:05:51 -07:00
genrtc.c Char: genrtc, use wait_event_interruptible 2007-07-16 09:05:44 -07:00
hangcheck-timer.c Detach sched.h from mm.h 2007-05-21 09:18:19 -07:00
hpet.c [PATCH] sysctl: remove insert_at_head from register_sysctl 2007-02-14 08:09:59 -08:00
hvc_beat.c [POWERPC] Celleb: hypervisor console driver 2007-02-07 14:03:21 +11:00
hvc_console.c Freezer: make kernel threads nonfreezable by default 2007-07-17 10:23:02 -07:00
hvc_console.h
hvc_iseries.c [POWERPC] Rename device_is_compatible to of_device_is_compatible 2007-05-07 20:31:14 +10:00
hvc_rtas.c
hvc_vio.c [POWERPC] Rename device_is_compatible to of_device_is_compatible 2007-05-07 20:31:14 +10:00
hvcs.c [PATCH] tty: switch to ktermios 2006-12-08 08:28:57 -08:00
hvsi.c [POWERPC] Rename get_property to of_get_property: partial drivers 2007-04-27 15:51:56 +10:00
i8k.c i386: sched.h inclusion from module.h is baack 2007-05-08 11:15:08 -07:00
ip27-rtc.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
isicom.c Char: isicom, use pr_debug 2007-05-08 11:15:24 -07:00
istallion.c serial: remove termios checks from various old char serial drivers 2007-07-16 09:05:52 -07:00
keyboard.c Kernel utf-8 handling 2007-07-16 09:05:46 -07:00
lcd.c [CHAR] lcd: Fix two warnings. 2007-03-17 01:03:26 +00:00
lcd.h [MIPS] Add MTD device support for Cobalt 2007-02-20 17:11:55 +00:00
lp.c ROUND_UP macro cleanup in drivers/char/lp.c 2007-05-08 11:15:08 -07:00
mbcs.c [PATCH] mark struct file_operations const 3 2007-02-12 09:48:45 -08:00
mbcs.h
mem.c Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus 2007-07-10 14:48:43 -07:00
misc.c Make /proc/misc use seq_list_xxx helpers 2007-07-16 09:05:42 -07:00
mmtimer.c [IA64-SN2][KJ] mmtimer.c-kzalloc 2007-05-08 11:53:27 -07:00
moxa.c old buffer overflow in moxa driver 2007-05-08 11:15:14 -07:00
mspec.c mspec_mmap: don't set VM_LOCKED 2007-07-16 09:05:36 -07:00
mxser.c serial: remove termios checks from various old char serial drivers 2007-07-16 09:05:52 -07:00
mxser.h [PATCH] mxser: remove ambiguous redefinition of INIT_WORK 2007-02-11 10:51:25 -08:00
mxser_new.c serial: remove termios checks from various old char serial drivers 2007-07-16 09:05:52 -07:00
mxser_new.h [PATCH] Char: mxser_new, upgrade to 1.9.15 2007-02-11 10:51:29 -08:00
n_hdlc.c Char: n_hdlc, allow RESTARTSYS retval of tty write 2007-07-16 09:05:43 -07:00
n_r3964.c Char: n_r3964, use wait_event_interruptible 2007-07-16 09:05:44 -07:00
n_tty.c Audit: add TTY input auditing 2007-07-16 09:05:47 -07:00
nsc_gpio.c [PATCH] struct path: convert char-drivers 2006-12-08 08:28:44 -08:00
nvram.c COBALT: remove all references to Cobalt NVRAM 2007-07-16 09:05:47 -07:00
nwbutton.c [PATCH] Char: timers cleanup 2007-02-12 09:48:30 -08:00
nwbutton.h
nwflash.c [PATCH] remove many unneeded #includes of sched.h 2007-02-14 08:09:54 -08:00
pc8736x_gpio.c
ppdev.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
pty.c [PATCH] remove many unneeded #includes of sched.h 2007-02-14 08:09:54 -08:00
random.c random: fix output buffer folding 2007-06-16 13:16:16 -07:00
raw.c [PATCH] raw: don't allow the creation of a raw device with minor number 0 2007-02-11 10:51:34 -08:00
riscom8.c drivers/char: use __set_current_state() 2007-05-08 11:15:13 -07:00
riscom8.h
riscom8_reg.h
rocket.c rocket.c: fix unchecked mutex_lock_interruptible() 2007-07-16 09:05:43 -07:00
rocket.h
rocket_int.h Kill unused sesssion and group values in rocket driver 2007-05-11 08:29:36 -07:00
rtc.c RTC: Ratelimit "lost interrupts" message 2007-07-16 09:05:43 -07:00
scc.h
scx200_gpio.c
selection.c Kernel utf-8 handling 2007-07-16 09:05:46 -07:00
ser_a2232.c [PATCH] remove many unneeded #includes of sched.h 2007-02-14 08:09:54 -08:00
ser_a2232.h
ser_a2232fw.ax
ser_a2232fw.h
serial167.c drivers/char: use __set_current_state() 2007-05-08 11:15:13 -07:00
snsc.c
snsc.h
snsc_event.c [IA64] drivers/char/snsc_event.c:206: warning: unused variable `p' 2007-05-10 13:23:05 -07:00
sonypi.c remove sonypi_camera_command() 2007-07-16 09:05:46 -07:00
specialix.c [PATCH] Char: timers cleanup 2007-02-12 09:48:30 -08:00
specialix_io8.h
stallion.c Char: stallion, fix oops during init with ISA cards 2007-06-24 08:59:11 -07:00
sx.c sx: switch subven and subid values 2007-07-10 17:51:13 -07:00
sx.h [PATCH] Char: sx, request regions 2006-12-08 08:28:59 -08:00
sxboards.h
sxwindow.h
synclink.c synclink: remove bogus 'no change' termios optimisation from synclink drivers 2007-07-16 09:05:51 -07:00
synclink_gt.c synclink: remove bogus 'no change' termios optimisation from synclink drivers 2007-07-16 09:05:51 -07:00
synclinkmp.c synclink: remove bogus 'no change' termios optimisation from synclink drivers 2007-07-16 09:05:51 -07:00
sysrq.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
tb0219.c [PATCH] struct path: convert char-drivers 2006-12-08 08:28:44 -08:00
tipar.c layered parport code uses parport->dev 2007-05-08 11:15:05 -07:00
tlclk.c [PATCH] remove many unneeded #includes of sched.h 2007-02-14 08:09:54 -08:00
toshiba.c [PATCH] remove many unneeded #includes of sched.h 2007-02-14 08:09:54 -08:00
tty_audit.c Audit: add TTY input auditing 2007-07-16 09:05:47 -07:00
tty_io.c Audit: add TTY input auditing 2007-07-16 09:05:47 -07:00
tty_ioctl.c Char: tty_ioctl, little whitespace cleanup 2007-07-16 09:05:44 -07:00
vc_screen.c use mutex instead of semaphore in virtual console driver 2007-05-08 11:15:33 -07:00
viocons.c [POWERPC] iSeries: fix viocons init 2006-12-20 16:37:48 +11:00
viotape.c [POWERPC] VIOTAPE: Use designated initializers for fops member structures. 2007-07-10 21:53:39 +10:00
vme_scc.c [PATCH] remove many unneeded #includes of sched.h 2007-02-14 08:09:54 -08:00
vr41xx_giu.c [MIPS] Separate platform_device registration for VR41xx GPIO 2007-07-12 17:41:15 +01:00
vt.c console UTF-8 fixes (fix) 2007-06-24 08:59:10 -07:00
vt_ioctl.c drivers/char: use __set_current_state() 2007-05-08 11:15:13 -07:00