Patch to eliminate struct files_struct.file_lock spinlock on the reader side
and use rcu refcounting rcuref_xxx api for the f_count refcounter. The
updates to the fdtable are done by allocating a new fdtable structure and
setting files->fdt to point to the new structure. The fdtable structure is
protected by RCU thereby allowing lock-free lookup. For fd arrays/sets that
are vmalloced, we use keventd to free them since RCU callbacks can't sleep. A
global list of fdtable to be freed is not scalable, so we use a per-cpu list.
If keventd is already handling the current cpu's work, we use a timer to defer
queueing of that work.
Since the last publication, this patch has been re-written to avoid using
explicit memory barriers and use rcu_assign_pointer(), rcu_dereference()
premitives instead. This required that the fd information is kept in a
separate structure (fdtable) and updated atomically.
Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
In order for the RCU to work, the file table array, sets and their sizes must
be updated atomically. Instead of ensuring this through too many memory
barriers, we put the arrays and their sizes in a separate structure. This
patch takes the first step of putting the file table elements in a separate
structure fdtable that is embedded withing files_struct. It also changes all
the users to refer to the file table using files_fdtable() macro. Subsequent
applciation of RCU becomes easier after this.
Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com>
Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Adds a set of primitives to do reference counting for objects that are looked
up without locks using RCU.
Signed-off-by: Ravikiran Thirumalai <kiran_th@gmail.com>
Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
First of a number of files_lock scaability patches.
Here are the x86 numbers -
tiobench on a 4(8)-way (HT) P4 system on ramdisk :
(lockfree)
Test 2.6.10-vanilla Stdev 2.6.10-fd Stdev
-------------------------------------------------------------
Seqread 1400.8 11.52 1465.4 34.27
Randread 1594 8.86 2397.2 29.21
Seqwrite 242.72 3.47 238.46 6.53
Randwrite 445.74 9.15 446.4 9.75
The performance improvement is very significant.
We are getting killed by the cacheline bouncing of the files_struct
lock here. Writes on ramdisk (ext2) seems to vary just too
much to get any meaningful number.
Also, With Tridge's thread_perf test on a 4(8)-way (HT) P4 xeon system :
2.6.12-rc5-vanilla :
Running test 'readwrite' with 8 tasks
Threads 0.34 +/- 0.01 seconds
Processes 0.16 +/- 0.00 seconds
2.6.12-rc5-fd :
Running test 'readwrite' with 8 tasks
Threads 0.17 +/- 0.02 seconds
Processes 0.17 +/- 0.02 seconds
I repeated the measurements on ramfs (as opposed to ext2 on ramdisk in
the earlier measurement) and I got more consistent results from tiobench :
4(8) way xeon P4
-----------------
(lock-free)
Test 2.6.12-rc5 Stdev 2.6.12-rc5-fd Stdev
-------------------------------------------------------------
Seqread 1282 18.59 1343.6 26.37
Randread 1517 7 2415 34.27
Seqwrite 702.2 5.27 709.46 5.9
Randwrite 846.86 15.15 919.68 21.4
4-way ppc64
------------
(lock-free)
Test 2.6.12-rc5 Stdev 2.6.12-rc5-fd Stdev
-------------------------------------------------------------
Seqread 1549 91.16 1569.6 47.2
Randread 1473.6 25.11 1585.4 69.99
Seqwrite 1096.8 20.03 1136 29.61
Randwrite 1189.6 4.04 1275.2 32.96
Also running Tridge's thread_perf test on ppc64 :
2.6.12-rc5-vanilla
--------------------
Running test 'readwrite' with 4 tasks
Threads 0.20 +/- 0.02 seconds
Processes 0.16 +/- 0.01 seconds
2.6.12-rc5-fd
--------------------
Running test 'readwrite' with 4 tasks
Threads 0.18 +/- 0.04 seconds
Processes 0.16 +/- 0.01 seconds
The benefits are huge (upto ~60%) in some cases on x86 primarily
due to the atomic operations during acquisition of ->file_lock
and cache line bouncing in fast path. ppc64 benefits are modest
due to LL/SC based locking, but still statistically significant.
This patch:
RCU head initilizer no longer needs the head varible name since we don't use
list.h lists anymore.
Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- Removed kernel version dependency from tea575x-tuner.h
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- Include saa6588 compiler option and files.
- Fix comment on tuner.h
- linux/utsname.h replaced by linux/version.h to compile on vanilla 2.6.13
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- Remove $Id CVS logs for V4L files
- Included newer cards.
- Added a new NEC protocol for ir based on pulse distance.
- Enable ATSC support for DViCO FusionHDTV5 Gold.
- Added tuner LG NTSC (TALN mini series).
- Fixed tea5767 autodetection.
- Resolve more tuner types.
- Commented debug function removed from mainstream.
- Remove comments from mainstream. Still on development tree.
- linux/version dependencies removed.
- BTSC Lang1 now is set to auto_stereo mode.
- New tuner standby API.
- i2c-core.c uses hexadecimal for the i2c address, so it should stay consistent.
Signed-off-by: Uli Luckas <luckas@musoft.de>
Signed-off-by: Mac Michaels <wmichaels1@earthlink.net>
Signed-off-by: Michael Krufky <mkrufky@m1k.net>
Signed-off-by: Hermann Pitton <hermann.pitton@onlinehome.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@brturbo.com.br>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add a devname parameter to the pcmcia_device structure, fills it with
"pcmcia<bus_id>" in pcmcia_device_add, and passes it to request_irq in
pcmcia_request_irq.
Signed-off-by: Brice Goglin <Brice.Goglin@ens-lyon.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Share code between setup-bus.c and yenta_socket.c: use the write-out code of
resources to the bridge also in yenta_socket.c, as it provides useful debug
output. In addition, it fixes the bug that the CPU-centric resource view
might need to be transferred to the PCI-centric view: setup-bus.c does that,
while yenta-socket.c did not.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Remove all #include <linux/version.h> and all references to LINUX_VERSION_CODE
and KERNEL_VERSION. Based on patch by Olaf Hering.
Signed-off-by: Olaf Hering <olh@suse.de>
Signed-off-by: Johannes Stezenbach <js@linuxtv.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I have a system (Biostar IDEQ210M mini-pc with a VIA chipset) which will
not reboot unless a keyboard is plugged in to it. I have tried all
combinations of the kernel "reboot=x,y" flags to no avail. Rebooting by
any method will leave the system in a wedged state (at the "Restarting
system" message).
I finally tracked the problem down to the machine's refusal to fully reboot
unless the keyboard controller status register had bit 2 set. This is the
"System flag" which when set, indicates successful completion of the
keyboard controller self-test (Basic Assurance Test, BAT).
I suppose that something is trying to protect against sporadic reboots
unless the keyboard controller is in a good state (a keyboard is present),
but I need this machine to be headless.
I found that setting the system flag (via the command byte) before giving
the "pulse reset line" command will allow the reboot to proceed. The patch
is simple, and I think it should be fine for everybody whether they have
this type of machine or not. This affects the "hard" reboot (as done when
the kernel boot flags "reboot=c,h" are used).
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The function prototype for handle_IRQ_event() in a few architctures is not
needed because they use GENERIC_HARDIRQ.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
For architecture like ia64, the switch stack structure is fairly large
(currently 528 bytes). For context switch intensive application, we found
that significant amount of cache misses occurs in switch_to() function.
The following patch adds a hook in the schedule() function to prefetch
switch stack structure as soon as 'next' task is determined. This allows
maximum overlap in prefetch cache lines for that structure.
Signed-off-by: Ken Chen <kenneth.w.chen@intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following patch changes the usages of PVR_440* into strcmp's with the
cpu_name field, and removes the defines altogether. The Ebony portion was
briefly tested long ago. One benefit of moving from PVR-tests to string
tests in general is that not all CPUs can be on and be able to do this type
of comparison.
See http://patchwork.ozlabs.org/linuxppc/patch?id=1250 for the original
thread.
Signed-off-by: Tom Rini <trini@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch removes the inode_post_link and inode_post_rename LSM hooks as
they are unused (and likely useless).
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch removes the inode_post_create/mkdir/mknod/symlink LSM hooks as
they are obsoleted by the new inode_init_security hook that enables atomic
inode security labeling.
If anyone sees any reason to retain these hooks, please speak now. Also,
is anyone using the post_rename/link hooks; if not, those could also be
removed.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following patch set enables atomic security labeling of newly created
inodes by altering the fs code to invoke a new LSM hook to obtain the security
attribute to apply to a newly created inode and to set up the incore inode
security state during the inode creation transaction. This parallels the
existing processing for setting ACLs on newly created inodes. Otherwise, it
is possible for new inodes to be accessed by another thread via the dcache
prior to complete security setup (presently handled by the
post_create/mkdir/... LSM hooks in the VFS) and a newly created inode may be
left unlabeled on the disk in the event of a crash. SELinux presently works
around the issue by ensuring that the incore inode security label is
initialized to a special SID that is inaccessible to unprivileged processes
(in accordance with policy), thereby preventing inappropriate access but
potentially causing false denials on legitimate accesses. A simple test
program demonstrates such false denials on SELinux, and the patch solves the
problem. Similar such false denials have been encountered in real
applications.
This patch defines a new inode_init_security LSM hook to obtain the security
attribute to apply to a newly created inode and to set up the incore inode
security state for it, and adds a corresponding hook function implementation
to SELinux.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch pulls the PCI-related junk out of struct device_node and
puts it in a separate structure, struct pci_dn. The device_node now
just has a void * pointer in it, which points to a struct pci_dn for
nodes that represent PCI devices. It could potentially be used in
future for device-specific data for other sorts of devices, such as
virtual I/O devices.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Remove asm-ppc64/segment.h now that all users are gone.
Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Fix __power64__ typo that should be __powerpc64__ instead.
Signed-off-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Merge a few asm-ppc and asm-ppc64 header files.
Note: the merge of setup.h intentionally does not carry
forward the m68k cruft. That means this patch continues
to break the already broken amiga on the ppc32.
Signed-off-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Make check_bugs() static inline and remove it from syscalls.c.
Signed-off-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Standardize on _ASM_POWERPC_... prefix for all #include
exclusion symbols. Fixup all the non-compilers.
Signed-off-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Include the ColdFire 523x register definitions when compiling
for that target processor.
Signed-off-by: Greg Ungerer <gerg@uclinux.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add support definitions for the integrated UARTs on the 523x ColdFire
processor family.
Signed-off-by: Greg Ungerer <gerg@uclinux.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add processor level and clock support defines for the ColdFire 523x
processor.
Signed-off-by: Greg Ungerer <gerg@uclinux.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
29 July 2005, Cambridge, MA:
This afternoon Alan Stern submitted a patch to remove the URB_ASYNC_UNLINK
flag from the Linux kernel. Mr. Stern explained, "This flag is a relic
from an earlier, less-well-designed system. For over a year it hasn't
been used for anything other than printing warning messages."
An anonymous spokesman for the Linux kernel development community
commented, "This is exactly the sort of thing we see happening all the
time. As the kernel evolves, support for old techniques and old code can
be jettisoned and replaced by newer, better approaches. Proprietary
operating systems do not have the freedom or flexibility to change so
quickly."
Mr. Stern, a staff member at Harvard University's Rowland Institute who
works on Linux only as a hobby, noted that the patch (labelled as548) did
not update two files, keyspan.c and option.c, in the USB drivers' "serial"
subdirectory. "Those files need more extensive changes," he remarked.
"They examine the status field of several URBs at times when they're not
supposed to. That will need to be fixed before the URB_ASYNC_UNLINK flag
is removed."
Greg Kroah-Hartman, the kernel maintainer responsible for overseeing all
of Linux's USB drivers, did not respond to our inquiries or return our
calls. His only comment was "Applied, thanks."
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch removes support for user-provided platform-specific hardware reset
and clock starting/stopping functions. Hardware reset was needed earlier as
getting the software reset working was tricky due to the lack of documentation.
Recently, a number of people using isp116x have said the software reset is
working for them.
I haven't heard of anybody using the clock starting/stopping.
Signed-off-by: Olav Kongas <ok@artecdesign.ee>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch sets the isp116x to report overcurrent always per-port.
Signed-off-by: Olav Kongas <ok@artecdesign.ee>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The isp116x chip will now always be in per-port power switching mode. Remove
conf options to set any other mode.
Signed-off-by: Olav Kongas <ok@artecdesign.ee>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch removes the power-on-to-power-good-time configuration option for
isp116x-hcd.
Signed-off-by: Olav Kongas <ok@artecdesign.ee>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch introduces a /sys/class/usb_device/ class
where every connected usb-device will show up:
tree /sys/class/usb_device/
/sys/class/usb_device/
|-- usb1.1
| |-- dev
| `-- device -> ../../../devices/pci0000:00/0000:00:1d.0/usb1
|-- usb2.1
| |-- dev
| `-- device -> ../../../devices/pci0000:00/0000:00:1d.1/usb2
...
The presence of the "dev" file lets udev create real device nodes.
kay@pim:~/src/linux-2.6> tree /dev/bus/usb/
/dev/bus/usb/
|-- 1
| `-- 1
|-- 2
| `-- 1
...
udev rule:
SUBSYSTEM="usb_device", PROGRAM="/sbin/usb_device %k", NAME="%c"
(echo $1 | /bin/sed 's/usb\([0-9]*\)\.\([0-9]*\)/bus\/usb\/\1\/\2/')
This makes libusb pick up the real nodes instead of the mounted usbfs:
export USB_DEVFS_PATH=/dev/bus/usb
Background:
All this makes it possible to manage usb devices with udev instead of
the devfs solution. We are currently working on a pam_console/resmgr
replacement driven by udev and a pam-helper. It applies ACL's to device
nodes, which is required for modern desktop functionalty like
"Fast User Switching" or multiple local login support.
New patch with its own major. I've succesfully disabled usbfs and use real
nodes only on my box. With: "export USB_DEVFS_PATH=/dev/bus/usb" libusb picks
up the udev managed nodes instead of reading usbfs files.
This makes udev to provide symlinks for libusb to pick up:
SUBSYSTEM="usb_device", PROGRAM="/sbin/usbdevice %k", SYMLINK="%c"
/sbin/usbdevice:
#!/bin/sh
echo $1 | /bin/sed 's/usbdev\([0-9]*\)\.\([0-9]*\)/bus\/usb\/\1\/\2/'
Signed-off-by: Kay Sievers <kay.sievers@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Dipankar Sarma