a number of small patches:
- include notifier.h include file
- re-arrange prototype functions
- remove =0 initializations
- change printk logging levels to what's used in other drivers
- /dev/watchdog is a VFS so use nonseekable_open
- Style: Instead of "if (constant op function_or_variable)"
we prefer "if (function_or_variable op constant)"
- arg is a __user pointer
- use MAX_TIMEOUT_SECONDS instead of 32 in WDIOC_SETTIMEOUT
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Wim Van Sebroeck [Sun, 12 Nov 2006 17:05:09 +0000 (18:05 +0100)]
[WATCHDOG] Add iTCO vendor specific support
Add vendor specific support to the intel TCO timer based watchdog
devices. At this moment we only have additional support for some
SuperMicro Inc. motherboards.
Signed-off-by: Robert Seretny <lkpatches@paypc.com> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Andrew Victor [Tue, 26 Sep 2006 15:49:30 +0000 (17:49 +0200)]
[WATCHDOG] Atmel AT91RM9200 rename.
The new Atmel AT91SAM9261 and AT91SAM9260 processors use a different
internal watchdog peripheral. This watchdog driver is therefore
AT91RM9200-specific.
This patch renames at91_wdt.c to at91rm9200_wdt.c, and changes the name
of the configuration option.
Signed-off-by: Andrew Victor <andrew@sanpeople.com> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Jeff Garzik [Tue, 10 Oct 2006 07:40:44 +0000 (03:40 -0400)]
[WATCHDOG] watchdog/iTCO_wdt: fix bug related to gcc uninit warning
gcc emits the following warning:
drivers/char/watchdog/iTCO_wdt.c: In function ‘iTCO_wdt_ioctl’:
drivers/char/watchdog/iTCO_wdt.c:429: warning: ‘time_left’ may be used uninitialized in this function
This indicates a condition near enough to a bug, to want to fix.
iTCO_wdt_get_timeleft() stores a value in 'time_left' iff
iTCO_version==(1 or 2). This driver only supports versions
1 or 2, so this is ok. However, since (a) the return value of
iTCO_wdt_get_timeleft() is handled anyway, (b) it fixes the warning,
and (c) it future-proofs the driver, we go ahead and add the obvious
return value.
Signed-off-by: Jeff Garzik <jeff@garzik.org> Signed-off-by: Wim Van Sebroeck <wim@iguana.be> Signed-off-by: Andrew Morton <akpm@osdl.org>
Samuel Tardieu [Thu, 7 Sep 2006 09:57:00 +0000 (11:57 +0200)]
[WATCHDOG] w83697hf/hg WDT driver - patch 16
This is patch 16 in the series of patches that converts
Marcus Junker's w83697hf watchdog driver to Samuel Tardieau's
w83697hf/hg watchdog driver.
This patch contains following changes:
- Add copyright notice for Samuel Tardieu also.
This is the last patch in this series.
The original description for Samuel's driver was:
driver for the Winbond W83697HF/W83697HG watchdog timer
The Winbond SuperIO W83697HF/HG includes a watchdog that can count from
1 to 255 seconds (or minutes). This drivers allows the seconds mode to
be used. It exposes a standard /dev/watchdog interface. This chip is
currently being used on some motherboards designed by VIA.
By default, the module looks for a chip at I/O port 0x2e. The chip can
be configured to be at 0x4e on some motherboards, the address can be
chosen using the wdt_io module parameter. Using 0 will try to autodetect
the address.
Signed-off-by: Samuel Tardieu <sam@rfc1149.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Samuel Tardieu [Thu, 7 Sep 2006 09:57:00 +0000 (11:57 +0200)]
[WATCHDOG] w83697hf/hg WDT driver - patch 15
This is patch 15 in the series of patches that converts
Marcus Junker's w83697hf watchdog driver to Samuel Tardieau's
w83697hf/hg watchdog driver.
This patch contains following changes:
- Clean-up initialization code - part 2:
* the line reading "set second mode & disable keyboard ..."
is plain wrong, the register being manipulated (CRF4) is
the counter itself, not the control byte (CRF3) -- looks
like it has been copied from another driver.
* I think garbage is being written in CRF3 (the control word)
as the timeout value is being stored in this register (such
as 60 for 60 seconds).
* We only want to set pin 119 to WDTO# mode and leave the rest
of CR29 like it is.
* Set count mode to seconds and not minutes.
Signed-off-by: Samuel Tardieu <sam@rfc1149.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Samuel Tardieu [Thu, 7 Sep 2006 09:57:00 +0000 (11:57 +0200)]
[WATCHDOG] w83697hf/hg WDT driver - patch 14
This is patch 14 in the series of patches that converts
Marcus Junker's w83697hf watchdog driver to Samuel Tardieau's
w83697hf/hg watchdog driver.
This patch contains following changes:
- Clean-up initialization code (part 1: remove
w83697hf_select_wd_register() and
w83697hf_unselect_wd_register() functions).
- Make sure that the watchdog device is stopped
as soon as we found it.
Signed-off-by: Samuel Tardieu <sam@rfc1149.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Samuel Tardieu [Thu, 7 Sep 2006 09:57:00 +0000 (11:57 +0200)]
[WATCHDOG] w83697hf/hg WDT driver - patch 13
This is patch 13 in the series of patches that converts
Marcus Junker's w83697hf watchdog driver to Samuel Tardieau's
w83697hf/hg watchdog driver.
This patch contains following changes:
- Remove wdt_ctrl (it has been replaced with the
w83697hf_write_timeout() function) and redo/clean-up
the start/stop/ping code.
- Make sure that the watchdog is enabled or disabled
When starting or stoping the device (with a call
to w83697hf_set_reg(0x30, ?); ).
Signed-off-by: Samuel Tardieu <sam@rfc1149.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Samuel Tardieu [Thu, 7 Sep 2006 09:57:00 +0000 (11:57 +0200)]
[WATCHDOG] w83697hf/hg WDT driver - patch 11
This is patch 11 in the series of patches that converts
Marcus Junker's w83697hf watchdog driver to Samuel Tardieau's
w83697hf/hg watchdog driver.
This patch contains following changes:
- Add w83697hf_select_wdt() and w83697hf_deselect_wdt()
so that the start/stop/ping code can directly talk to
the watchdog.
Signed-off-by: Samuel Tardieu <sam@rfc1149.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Samuel Tardieu [Thu, 7 Sep 2006 09:57:00 +0000 (11:57 +0200)]
[WATCHDOG] w83697hf/hg WDT driver - patch 1
This is patch 1 in the series of patches that converts
Marcus Junker's w83697hf watchdog driver to Samuel Tardieau's
w83697hf/hg watchdog driver.
This patch contains following changes:
- the note concerning tyan motherboards has been copied from
another driver, This doesn't apply here.
- the comments concerning CRF6 are wrong as CRF3 is manipulated
and CRF6 is never read nor written.
- the comments concerning CRF5 are wrong as CRF4 is manipulated
and CRF5 is never read nor written.
Signed-off-by: Samuel Tardieu <sam@rfc1149.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
[WATCHDOG] use ENOTTY instead of ENOIOCTLCMD in ioctl()
Return ENOTTY instead of ENOIOCTLCMD in user-visible ioctl() results
The watchdog drivers used to return ENOIOCTLCMD for bad ioctl() commands.
ENOIOCTLCMD should not be visible by the user, so use ENOTTY instead.
Signed-off-by: Samuel Tardieu <sam@rfc1149.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be> Acked-by: Alan Cox <alan@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org>
Add io spinlocks to prevent possible race
conditions between start and stop operations
that are issued from different child processes
where the master process opened /dev/watchdog.
* Added io spinlocking
* Deleted WATCHDOG_MINOR (it's in the miscdevice include
* Changed timer_enabled to use set_bit functions
* WDIOC_GETSUPPORT should return -EFAULT or 0
* timeout should be correct before we initialize the watchdog
* we should initialize the watchdog before we give access
to userspace
* Third parameter of module_param is not the default or
initial value
The include of linux/smp.h needs to be done before the #if that
checks for the compiler version. Seems like fallout from the
inline assembly cleanup patch vs. the directed yield patch.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Fix new restore_sigregs function. It copies the user space copy of the
old psw without correcting the psw.mask and the psw.addr high order bit.
While we are at it, simplify save_sigregs a bit.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Linus Torvalds [Wed, 4 Oct 2006 17:44:01 +0000 (10:44 -0700)]
Merge branch 'for-2.6.19' of git://brick.kernel.dk/data/git/linux-2.6-block
* 'for-2.6.19' of git://brick.kernel.dk/data/git/linux-2.6-block:
[PATCH] Document bi_sector and sector_t
[PATCH] helper function for retrieving scsi_cmd given host based block layer tag
[PATCH] helper function for retrieving scsi_cmd given host based block layer tag
This was necessitated by the need for a function to get back
to a scsi_cmnd, when an hba the posts its (corresponding) completion
interrupt with a block layer tag as its reference.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: David Somayajulu <david.somayajulu@qlogic.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* master.kernel.org:/pub/scm/linux/kernel/git/mchehab/v4l-dvb:
V4L/DVB (4712): Fix warning when compiling on x86_i64
V4L/DVB (4711): Radio: No need to return void
V4L/DVB (4708): Add tveeprom support for Philips FM1236/FM1216ME MK5
V4L/DVB (4707): 4linux: complete conversion to hotplug safe PCI API
V4L/DVB (4706): Do not enable VIDEO_V4L2 unconditionally
V4L/DVB (4704): SAA713x: fixed compile warning in SECAM fixup
V4L/DVB (4703): Add support for the ASUS EUROPA2 OEM board
V4L/DVB (4702): Fix: set antenna input for DVB-T for Asus P7131 Dual hybrid
V4L/DVB (4701): Saa713x audio fixes
V4L/DVB (4676a): Remove Kconfig item for DiB7000M support
[PATCH] atmel_serial: Fix roundoff error in atmel_console_get_options
The atmel_console_get_options() function initializes the baud,
parity and bits settings from the actual hardware setup, in
case it has been initialized by a e.g. boot loader.
The baud rate, however, is not necessarily exactly equal to one of
the standard baud rates (115200, etc.) This means that the baud rate
calculated by this function may be slightly higher or slightly lower
than one of the standard baud rates.
If the baud rate is slightly lower than the target, this causes
problems when uart_set_option() tries to match the detected baud rate
against the standard baud rate, as it will always select a baud rate
that is lower or equal to the target rate. For example if the
detected baud rate is slightly lower than 115200, usart_set_options()
will select 57600.
This patch fixes the problem by subtracting 1 from the value in BRGR
when calculating the baud rate. The detected baud rate will thus
always be higher than the nearest standard baud rate, and
uart_set_options() will end up doing the right thing.
Tested on ATSTK1000 and AT91RM9200-EK boards. Both are broken without
this patch.
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Acked-by: Andrew Victor <andrew@sanpeople.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] AVR32: Allow renumbering of serial devices
Allow the board to remap actual USART peripheral devices to serial
devices by calling at32_map_usart(hw_id, serial_line). This ensures
that even though ATSTK1002 uses USART1 as the first serial port, it
will still have a ttyS0 device.
This also adds a board-specific early setup hook and moves the
at32_setup_serial_console() call there from the platform code.
[PATCH] atmel_serial: Pass fixed register mappings through platform_data
In order to initialize the serial console early, the atmel_serial
driver had to do a hack where it compared the physical address of the
port with an address known to be permanently mapped, and used it as a
virtual address. This got around the limitation that ioremap() isn't
always available when the console is being initalized.
This patch removes that hack and replaces it with a new "regs" field
in struct atmel_uart_data that the board-specific code can initialize
to a fixed virtual mapping for platform devices where this is possible.
It also initializes the DBGU's regs field with the address the driver
used to check against.
On AVR32, the "regs" field is initialized from the physical base
address when this it can be accessed through a permanently 1:1 mapped
segment, i.e. the P4 segment.
If regs is NULL, the console initialization is delayed until the "real"
driver is up and running and ioremap() can be used.
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Acked-by: Andrew Victor <andrew@sanpeople.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The at91_serial driver can be used with both AT32 and AT91 devices
from Atmel and has therefore been renamed atmel_serial. The only
thing left is to rename PORT_AT91 PORT_ATMEL.
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Acked-by: Andrew Victor <andrew@sanpeople.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Vitaly Wool [Wed, 4 Oct 2006 15:19:58 +0000 (19:19 +0400)]
[MIPS] PNX8550 fixups
This patch fixes the compilation errors on PNX8550 and hard-to-track
bug in interrupt handling.
It also corresponds to the latest changes in PNX8550 serial driver.
* master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6:
[XFRM]: BEET mode
[TCP]: Kill warning in tcp_clean_rtx_queue().
[NET_SCHED]: Remove old estimator implementation
[ATM]: [zatm] always *pcr in alloc_shaper()
[ATM]: [ambassador] Change the return type to reflect reality
[ATM]: kmalloc to kzalloc patches for drivers/atm
[TIPC]: fix printk warning
[XFRM]: Clearing xfrm_policy_count[] to zero during flush is incorrect.
[XFRM] STATE: Use destination address for src hash.
[NEIGH]: always use hash_mask under tbl lock
[UDP]: Fix MSG_PROBE crash
[UDP6]: Fix flowi clobbering
[NET_SCHED]: Revert "HTB: fix incorrect use of RB_EMPTY_NODE"
[NETFILTER]: ebt_mark: add or/and/xor action support to mark target
[NETFILTER]: ipt_REJECT: remove largely duplicate route_reverse function
[NETFILTER]: Honour source routing for LVS-NAT
[NETFILTER]: add type parameter to ip_route_me_harder
[NETFILTER]: Kconfig: fix xt_physdev dependencies
* master.kernel.org:/pub/scm/linux/kernel/git/willy/parisc-2.6: (41 commits)
[PARISC] Kill wall_jiffies use
[PARISC] Honour "panic_on_oops" sysctl
[PARISC] Fix fs/binfmt_som.c
[PARISC] Export clear_user_page to modules
[PARISC] Make DMA routines more stubby
[PARISC] Define pci_get_legacy_ide_irq
[PARISC] Fix CONFIG_DEBUG_SPINLOCK
[PARISC] Fix HPUX compat compile with current GCC
[PARISC] Fix iounmap compile warning
[PARISC] Add support for Quicksilver AGPGART
[PARISC] Move LBA and SBA register defines to the common ropes.h
[PARISC] Create shared <asm/ropes.h> header
[PARISC] Stash the lba_device in its struct device drvdata
[PARISC] Generalize IS_ASTRO et al to take a parisc_device like
[PARISC] Pretty print the name of the lba type on kernel boot
[PARISC] Remove some obsolete comments and I checked that Reo is similar to Ike
[PARISC] Add hardware found in the rp8400
[PARISC] Allow nested interrupts
[PARISC] Further updates to timer_interrupt()
[PARISC] remove halftick and copy clocktick to local var (gcc can optimize usage)
...
* git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (25 commits)
[POWERPC] Add support for the mpc832x mds board
[POWERPC] Add initial support for the e300c2 core
[POWERPC] Add MPC8360EMDS default dts file
[POWERPC] Add MPC8360EMDS board support
[POWERPC] Add QUICC Engine (QE) infrastructure
[POWERPC] Add QE device tree node definition
[POWERPC] Don't try to just continue if xmon has no input device
[POWERPC] Fix a printk in pseries_mpic_init_IRQ
[POWERPC] Get default baud rate in udbg_scc
[POWERPC] Fix zImage.coff on oldworld PowerMac
[POWERPC] Fix xmon=off and cleanup xmon initialisation
[POWERPC] Cleanup include/asm-powerpc/xmon.h
[POWERPC] Update swim3 printk after blkdev.h change
[POWERPC] Cell interrupt rework
POWERPC: mpc82xx merge: board-specific/platform stuff(resend)
POWERPC: 8272ads merge to powerpc: common stuff
POWERPC: Added devicetree for mpc8272ads board
[POWERPC] iSeries has no legacy I/O
[POWERPC] implement BEGIN/END_FW_FTR_SECTION
[POWERPC] iSeries does not need pcibios_fixup_resources
...
Linus Torvalds [Wed, 4 Oct 2006 15:15:55 +0000 (08:15 -0700)]
Merge branch 'audit.b32' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current
* 'audit.b32' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current:
[PATCH] message types updated
[PATCH] name_count array overrun
[PATCH] PPID filtering fix
[PATCH] arch filter lists with < or > should not be accepted
Alan Cox [Wed, 4 Oct 2006 11:47:14 +0000 (12:47 +0100)]
[PATCH] pata: teach ali about rev C8, keep pcmcia driver in sync
This fixes support for rev c8 of the ALi/ULi PATA, and keeps pcmcia in
sync so ide_cs and pata_pcmcia are interchangable, both are only changes
to constants.
Right now rev 0xC8 and higher don't work with libata but 0xc8 is in the
field now.
Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Linus Torvalds [Wed, 4 Oct 2006 15:06:16 +0000 (08:06 -0700)]
Merge branch 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/libata-dev
* 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/libata-dev:
[libata] pata_artop: kill gcc warning
[PATCH] libata: turn off NCQ if queue depth is adjusted to 1
[PATCH] libata: cosmetic changes to constants
[libata] DocBook minor updates, fixes
[libata] PCI ID table cleanup in various drivers
[libata] Print out Status register, if a BSY-sleep takes too long
[libata] init probe_ent->private_data in a common location
[libata] minor PCI IDE probe fixes and cleanups
[libata] Use new PCI_VDEVICE() macro to dramatically shorten ID lists
[PATCH] Fix reference of uninitialised memory in ata_device_add()
If you lose the x bit (eg: by using patch(1)), powerpc won't build. Be
defensive about it...
Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Adrian Bunk [Wed, 4 Oct 2006 09:17:22 +0000 (02:17 -0700)]
[PATCH] The scheduled removal of some OSS drivers
This patch contains the scheduled removal of OSS drivers that:
- have ALSA drivers for the same hardware without known regressions and
- whose Kconfig options have been removed in 2.6.17.
[michal.k.k.piotrowski@gmail.com: build fix] Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Michal Piotrowski <michal.k.k.piotrowski@gmail.com> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Josh Triplett [Wed, 4 Oct 2006 09:17:21 +0000 (02:17 -0700)]
[PATCH] RCU: CREDITS and MAINTAINERS
Add MAINTAINERS entry for Read-Copy Update (RCU), listing Dipankar Sarma as
maintainer, and giving the URL for Paul McKenney's RCU site. Add
MAINTAINERS entry for rcutorture, listing myself as maintainer. Add
CREDITS entries for developers of RCU, RCU variants, and rcutorture. Use
Paul McKenney's preferred email address in include/linux/rcupdate.h .
Signed-off-by: Josh Triplett <josh@freedesktop.org> Cc: Paul McKenney <paulmck@us.ibm.com> Cc: Dipankar Sarma <dipankar@in.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Oleg Nesterov [Wed, 4 Oct 2006 09:17:17 +0000 (02:17 -0700)]
[PATCH] rcu: simplify/improve batch tuning
Kill a hard-to-calculate 'rsinterval' boot parameter and per-cpu
rcu_data.last_rs_qlen. Instead, it adds adds a flag rcu_ctrlblk.signaled,
which records the fact that one of CPUs has sent a resched IPI since the
last rcu_start_batch().
Roughly speaking, we need two rcu_start_batch()s in order to move callbacks
from ->nxtlist to ->donelist. This means that when ->qlen exceeds qhimark
and continues to grow, we should send a resched IPI, and then do it again
after we gone through a quiescent state.
On the other hand, if it was already sent, we don't need to do it again
when another CPU detects overflow of the queue.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Josh Triplett [Wed, 4 Oct 2006 09:17:16 +0000 (02:17 -0700)]
[PATCH] rcu: add rcu_bh_sync torture type to rcutorture
Use the newly-generic synchronous deferred free function to implement torture
testing for rcu_bh using synchronize_rcu_bh rather than the asynchronous
call_rcu_bh.
Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Josh Triplett [Wed, 4 Oct 2006 09:17:15 +0000 (02:17 -0700)]
[PATCH] rcu: add rcu_sync torture type to rcutorture
Use the newly-generic synchronous deferred free function to implement torture
testing for RCU using synchronize_rcu rather than the asynchronous call_rcu.
Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Josh Triplett [Wed, 4 Oct 2006 09:17:14 +0000 (02:17 -0700)]
[PATCH] rcu: refactor srcu_torture_deferred_free to work for any implementation
Make srcu_torture_deferred_free use cur_ops->sync() so it will work for any
implementation. Move and rename it in preparation for use in the ops of other
implementations.
Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Josh Triplett [Wed, 4 Oct 2006 09:17:13 +0000 (02:17 -0700)]
[PATCH] RCU: add fake writers to rcutorture
rcutorture currently has one writer and an arbitrary number of readers. To
better exercise some of the code paths in RCU implementations, add fake
writer threads which call the synchronize function for the RCU variant in a
loop, with a delay between calls to arrange for different numbers of
writers running in parallel.
[bunk@stusta.de: cleanup] Acked-by: Paul McKenney <paulmck@us.ibm.com> Cc: Dipkanar Sarma <dipankar@in.ibm.com> Signed-off-by: Josh Triplett <josh@freedesktop.org> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Josh Triplett [Wed, 4 Oct 2006 09:17:12 +0000 (02:17 -0700)]
[PATCH] rcu: Fix sign bug making rcu_random always return the same sequence
rcu_random uses a counter rrs_count to occasionally mix data from
get_random_bytes into the state of its pseudorandom generator. However,
the rrs_counter gets declared as an unsigned long, and rcu_random checks
for --rrs_count < 0, so this code will never mix any real random data into
the state, and will thus always return the same sequence of random numbers.
Also, change the return value of rcu_random from long to unsigned long, to
avoid potential issues caused by the use of the % operator, which can
return negative values for negative left operands.
Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Josh Triplett [Wed, 4 Oct 2006 09:17:11 +0000 (02:17 -0700)]
[PATCH] rcu: Avoid kthread_stop on invalid pointer if rcutorture reader startup fails
rcu_torture_init kmallocs the array of reader threads, then creates each
one with kthread_run, cleaning up with rcu_torture_cleanup if this fails.
rcu_torture_cleanup calls kthread_stop on any non-NULL pointer in the
array; however, any readers after the one that failed to start up will have
invalid pointers, not null pointers. Avoid this by using kzalloc instead.
Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Alan Stern [Wed, 4 Oct 2006 09:17:06 +0000 (02:17 -0700)]
[PATCH] cpufreq: make the transition_notifier chain use SRCU
This patch (as762) changes the cpufreq_transition_notifier_list from a
blocking_notifier_head to an srcu_notifier_head. This will prevent errors
caused attempting to call down_read() to access the notifier chain at a
time when interrupts must remain disabled, during system suspend.
It's not clear to me whether this is really necessary; perhaps the chain
could be made into an atomic_notifier. However a couple of the callout
routines do use blocking operations, so this approach seems safer.
The head of the notifier chain needs to be initialized before use; this is
done by an __init routine at core_initcall time. If this turns out not to
be a good choice, it can easily be changed.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: "Paul E. McKenney" <paulmck@us.ibm.com> Cc: Jesse Brandeburg <jesse.brandeburg@gmail.com> Cc: Dave Jones <davej@codemonkey.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Alan Stern [Wed, 4 Oct 2006 09:17:05 +0000 (02:17 -0700)]
[PATCH] SRCU: report out-of-memory errors
Currently the init_srcu_struct() routine has no way to report out-of-memory
errors. This patch (as761) makes it return -ENOMEM when the per-cpu data
allocation fails.
The patch also makes srcu_init_notifier_head() report a BUG if a notifier
head can't be initialized. Perhaps it should return -ENOMEM instead, but
in the most likely cases where this might occur I don't think any recovery
is possible. Notifier chains generally are not created dynamically.
[akpm@osdl.org: avoid statement-with-side-effect in macro] Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Alan Stern [Wed, 4 Oct 2006 09:17:04 +0000 (02:17 -0700)]
[PATCH] Add SRCU-based notifier chains
This patch (as751) adds a new type of notifier chain, based on the SRCU
(Sleepable Read-Copy Update) primitives recently added to the kernel. An
SRCU notifier chain is much like a blocking notifier chain, in that it must
be called in process context and its callout routines are allowed to sleep.
The difference is that the chain's links are protected by the SRCU
mechanism rather than by an rw-semaphore, so calling the chain has
extremely low overhead: no memory barriers and no cache-line bouncing. On
the other hand, unregistering from the chain is expensive and the chain
head requires special runtime initialization (plus cleanup if it is to be
deallocated).
SRCU notifiers are appropriate for notifiers that will be called very
frequently and for which unregistration occurs very seldom. The proposed
"task notifier" scheme qualifies, as may some of the network notifiers.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Acked-by: Chandra Seetharaman <sekharan@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
projects / linux-2.6 / log