Age | Commit message (Collapse) | Author |
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Split the S3C2400 out of S3C2410 memory.h files
ready for S3C2400 support to be added.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Reorganise the definition of the virtual addresses
used into a common header and update the users to
rename S3C2410 items into a more common S3C defined
macros.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Remove the static maps for the LCD and USB devices.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Move the S3C2400 values to their own include directory
series in include/asm-arm/arch-s3c2400 as the support
for the S3C2400 is best placed in its own arch directory.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Rename the S3C24XX configuration options for the watchdog
boot controls for moving to the arch/arm/plat-s3c moves.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Check for ARM926 based S3C24XX based devices as these
only have 64 byte FIFOs, and do not have the model
detection refisters in the same place as the ARM920
based CPUs
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Ensure we check for ARM926 in the uncompressor, as all current
ARM926s do not have an ID register and all have S3C2440 style
UARTs.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Move the uncompress.h to plat-s3c
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Rename DEBUG_S3C2410_PORT to DEBUG_S3C_PORT as well as
DEBUG_S3C2410_UART to DEBUG_S3C_UART as part of the updates
to moving to plat-s3c for S3C base support.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Rename CONFIG_S3C2410_LOWLEVEL_UART_PORT to be
CONFIG_S3C_LOWLEVEL_UART_PORT as we move to using
plat-s3c for base of S3C operations.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Update the debug macros for use with the new per-cpu
configuration and usage.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Move the common parts of the debug macros into include/asm-arm/plat-s3c
ready to be used for the common S3C support.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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This patch moves items of the s3c24xx support into
a new plat-s3c directory for items that use the
s3c24xx support but are not directly s3c24xx
compatible, such as the s3c2400 and s3c6400.
git mv commands:
git mv include/asm-arm/arch-s3c2410/iic.h include/asm-arm/plat-s3c/iic.h
git mv include/asm-arm/arch-s3c2410/nand.h include/asm-arm/plat-s3c/nand.h
git mv include/asm-arm/arch-s3c2410/regs-iic.h include/asm-arm/plat-s3c/regs-iic.h
git mv include/asm-arm/arch-s3c2410/regs-nand.h include/asm-arm/plat-s3c/regs-nand.h
git mv include/asm-arm/arch-s3c2410/regs-rtc.h include/asm-arm/plat-s3c/regs-rtc.h
git mv include/asm-arm/arch-s3c2410/regs-serial.h include/asm-arm/plat-s3c/regs-serial.h
git mv include/asm-arm/arch-s3c2410/regs-timer.h include/asm-arm/plat-s3c/regs-timer.h
git mv include/asm-arm/arch-s3c2410/regs-watchdog.h include/asm-arm/plat-s3c/regs-watchdog.h
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Slab destructors were no longer supported after Christoph's
c59def9f222d44bb7e2f0a559f2906191a0862d7 change. They've been
BUGs for both slab and slub, and slob never supported them
either.
This rips out support for the dtor pointer from kmem_cache_create()
completely and fixes up every single callsite in the kernel (there were
about 224, not including the slab allocator definitions themselves,
or the documentation references).
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
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* Add ATA_PIO[0-6] defines to <linux/ata.h>.
* Add ->pio_mask field to ide_pci_device_t and ide_hwif_t.
* Add PIO masks to host drivers.
<linux/ata.h> change ACK-ed by Jeff Garzik <jeff@garzik.org>.
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
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* Add ->host_flags to ide_hwif_t to store ide_pci_device_t.host_flags,
assign it in setup-pci.c:ide_pci_setup_ports().
* Add IDE_HFLAG_PIO_NO_{BLACKLIST,DOWNGRADE} to ide_pci_device_t.host_flags
and teach ide_get_best_pio_mode() about them. Also remove needless
!drive->id check while at it (drive->id is always present).
* Convert amd74xx, via82cxxx and ide-timing.h to use ide_get_best_pio_mode()
and then remove no longer needed ide_find_best_pio_mode().
There should be no functionality changes caused by this patch.
Acked-by: Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
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* Drop no longer needed "PIO data" argument from ide_get_best_pio_mode()
and convert all users accordingly.
* Remove no longer needed ide_pio_data_t.
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
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* Add ide_pio_cycle_time() helper.
* Use it in ali14xx/ht6560b/qd65xx/cmd64{0,x}/sl82c105 and pmac host drivers
(previously cycle time given by the device was only used for "pio" == 255).
* Remove no longer needed ide_pio_data_t.cycle_time field.
v2:
* Fix "ata_" prefix (Noticed by Jeff).
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
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* Rename ide_pci_device_t.flags to ide_pci_device_t.host_flags
and IDEPCI_FLAG_ISA_PORTS flag to IDE_HFLAG_ISA_PORTS.
* Add IDE_HFLAG_SINGLE flag for single channel devices.
* Convert core code and all IDE PCI drivers to use IDE_HFLAG_SINGLE
and remove no longer needed ide_pci_device_t.channels field.
v2:
* Fix issues noticed by Sergei:
- correct code alignment in scc_pata.c
- s/IDE_HFLAG_SINGLE/~IDE_HFLAG_SINGLE/ in serverworks.c
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
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* Add ide_dev_has_iordy() helper and use it sl82c105 host driver.
* Remove no longer needed ide_pio_data_t.use_iordy field.
v2/v3:
* Fix issues noticed by Sergei:
- correct patch description
- fix comment in ide_get_best_pio_mode()
v4:
* Fix "ata_" prefix (Noticed by Jeff).
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
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* Print info about overriding PIO mode in ide_get_best_pio_mode().
* Remove info about overriding PIO mode from cmd64{0,x} host drivers.
* Remove no longer needed ide_pio_data_t.overridden field.
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/selinux-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/selinux-2.6:
SELinux: use SECINITSID_NETMSG instead of SECINITSID_UNLABELED for NetLabel
SELinux: enable dynamic activation/deactivation of NetLabel/SELinux enforcement
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* 'for-linus' of git://oss.sgi.com:8090/xfs/xfs-2.6:
[XFS] Fix inode size update before data write in xfs_setattr
[XFS] Allow punching holes to free space when at ENOSPC
[XFS] Implement ->page_mkwrite in XFS.
[FS] Implement block_page_mkwrite.
Manually fix up conflict with Nick's VM fault handling patches in
fs/xfs/linux-2.6/xfs_file.c
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Currently, CONFIG_X86_CMPXCHG64 both enables boot-time checking of
the cmpxchg64b feature and enables compilation of the set_64bit() family.
Since the option is dependent on PAE, and since KVM depends on set_64bit(),
this effectively disables KVM on i386 nopae.
Simplify by removing the config option altogether: the boot check is made
dependent on CONFIG_X86_PAE directly, and the set_64bit() family is exposed
without constraints. It is up to users to check for the feature flag (KVM
does not as virtualiation extensions imply its existence).
Signed-off-by: Avi Kivity <avi@qumranet.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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* git://git.linux-nfs.org/pub/linux/nfs-2.6:
NFSv4: handle lack of clientaddr in option string
NFSv4: debug print ntohl(status) in nfs client callback xdr code
SUNRPC: Clean up the sillyrename code
NFS: Introduce struct nfs_removeargs+nfs_removeres
NFS: Use dentry->d_time to store the parent directory verifier.
SUNRPC: move bkl locking and xdr proc invocation into a common helper
NFSv4: Fix the nfsv4 readlink reply buffer alignment
NFSv4: Fix the readdir reply buffer alignment
NFSv4: More NFSv4 xdr cleanups
NFSv4: Try to recover from getfh failures in nfs4_xdr_dec_open
NFSv4: 'constify' lookup arguments.
NFSv4: Don't fail nfs4_xdr_dec_open if decode_restorefh() failed
NFSv4: Fix open state recovery
NFSD/SUNRPC: Fix the automatic selection of RPCSEC_GSS
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* 'release' of git://lm-sensors.org/kernel/mhoffman/hwmon-2.6: (44 commits)
i2c: Delete the i2c-isa pseudo bus driver
hwmon: refuse to load abituguru driver on non-Abit boards
hwmon: fix Abit Uguru3 driver detection on some motherboards
hwmon/w83627ehf: Be quiet when no chip is found
hwmon/w83627ehf: No need to initialize fan_min
hwmon/w83627ehf: Export the thermal sensor types
hwmon/w83627ehf: Enable VBAT monitoring
hwmon/w83627ehf: Add support for the VID inputs
hwmon/w83627ehf: Fix timing issues
hwmon/w83627ehf: Add error messages for two error cases
hwmon/w83627ehf: Convert to a platform driver
hwmon/w83627ehf: Update the Kconfig entry
make coretemp_device_remove() static
hwmon: Add LM93 support
hwmon: Improve the pwmN_enable documentation
hwmon/smsc47b397: Don't report missing fans as spinning at 82 RPM
hwmon: Add support for newer uGuru's
hwmon/f71805f: Add temperature-tracking fan control mode
hwmon/w83627ehf: Preserve speed reading when changing fan min
hwmon: fix detection of abituguru volt inputs
...
Manual fixup of trivial conflict in MAINTAINERS file
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* git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched:
[PATCH] sched: implement cpu_clock(cpu) high-speed time source
[PATCH] sched: fix the all pinned logic in load_balance_newidle()
[PATCH] sched: fix newly idle load balance in case of SMT
[PATCH] sched: sched_cacheflush is now unused
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When a CONFIG_USER_NS=n and a user tries to unshare some namespace other
than the user namespace, the dummy copy_user_ns returns NULL rather than
the old_ns.
This value then gets assigned to task->nsproxy->user_ns, so that a
subsequent setuid, which uses task->nsproxy->user_ns, causes a NULL
pointer deref.
Fix this by returning old_ns.
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Implement the cpu_clock(cpu) interface for kernel-internal use:
high-speed (but slightly incorrect) per-cpu clock constructed from
sched_clock().
This API, unused at the moment, will be used in the future by blktrace,
by the softlockup-watchdog, by printk and by lockstat.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Since Ingo's recent scheduler rewrite which was merged as commit
0437e109e1841607f2988891eaa36c531c6aa6ac sched_cacheflush is unused.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Fix a couple of bugs:
- Don't rely on the parent dentry still being valid when the call completes.
Fixes a race with shrink_dcache_for_umount_subtree()
- Don't remove the file if the filehandle has been labelled as stale.
Fix a couple of inefficiencies
- Remove the global list of sillyrenamed files. Instead we can cache the
sillyrename information in the dentry->d_fsdata
- Move common code from unlink_setup/unlink_done into fs/nfs/unlink.c
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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We need a common structure for setting up an unlink() rpc call in order to
fix the asynchronous unlink code.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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Since every invocation of xdr encode or decode functions takes the BKL now,
there's a lot of redundant lock_kernel/unlock_kernel pairs that we can pull
out into a common function.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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There are no users of i2c-isa left, so we can finally get rid of it.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
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master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
* 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6: (25 commits)
[TG3]: Fix msi issue with kexec/kdump.
[NET] XFRM: Fix whitespace errors.
[NET] TIPC: Fix whitespace errors.
[NET] SUNRPC: Fix whitespace errors.
[NET] SCTP: Fix whitespace errors.
[NET] RXRPC: Fix whitespace errors.
[NET] ROSE: Fix whitespace errors.
[NET] RFKILL: Fix whitespace errors.
[NET] PACKET: Fix whitespace errors.
[NET] NETROM: Fix whitespace errors.
[NET] NETFILTER: Fix whitespace errors.
[NET] IPV4: Fix whitespace errors.
[NET] DCCP: Fix whitespace errors.
[NET] CORE: Fix whitespace errors.
[NET] BLUETOOTH: Fix whitespace errors.
[NET] AX25: Fix whitespace errors.
[PATCH] mac80211: remove rtnl locking in ieee80211_sta.c
[PATCH] mac80211: fix GCC warning on 64bit platforms
[GENETLINK]: Dynamic multicast groups.
[NETLIKN]: Allow removing multicast groups.
...
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pci_ids.h needs two of the AMD NB device-ids namely, Addressmap and the Memory
Controller devices
This patch adds those to the pci_id.h include file
Signed-off-by: Douglas Thompson <dougthompson@xmission.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Change error check and clear variable from an atomic to an int
Signed-off-by: Dave Jiang <djiang@mvista.com>
Signed-off-by: Douglas Thompson <dougthompson@xmission.com
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Here's a driver for the Intel 3000 and 3010 memory controllers,
relative to today's Sourceforge code drop. This has only had light
testing (I've yet to actually see it handle a memory error) but it
detects my hardware correctly.
Signed-off-by: Jason Uhlenkott <juhlenko@akamai.com>
Signed-off-by: Douglas Thompson <dougthompson@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Provides a way for NMI reported errors on x86 to notify the EDAC
subsystem pending ECC errors by writing to a software state variable.
Here's the reworked patch. I added an EDAC stub to the kernel so we can
have variables that are in the kernel even if EDAC is a module. I also
implemented the idea of using the chip driver to select error detection
mode via module parameter and eliminate the kernel compile option.
Please review/test. Thx!
Also, I only made changes to some of the chipset drivers since I am
unfamiliar with the other ones. We can add similar changes as we go.
Signed-off-by: Dave Jiang <djiang@mvista.com>
Signed-off-by: Douglas Thompson <dougthompson@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This is the code for the "lg.ko" module, which allows lguest guests to
be launched.
[akpm@linux-foundation.org: update for futex-new-private-futexes]
[akpm@linux-foundation.org: build fix]
[jmorris@namei.org: lguest: use hrtimers]
[akpm@linux-foundation.org: x86_64 build fix]
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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lguest is a simple hypervisor for Linux on Linux. Unlike kvm it doesn't need
VT/SVM hardware. Unlike Xen it's simply "modprobe and go". Unlike both, it's
5000 lines and self-contained.
Performance is ok, but not great (-30% on kernel compile). But given its
hackability, I expect this to improve, along with the paravirt_ops code which
it supplies a complete example for. There's also a 64-bit version being
worked on and other craziness.
But most of all, lguest is awesome fun! Too much of the kernel is a big ball
of hair. lguest is simple enough to dive into and hack, plus has some warts
which scream "fork me!".
This patch:
This is the code and headers required to make an i386 kernel an lguest guest.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Share a little common code, reverse the arguments for consistency, drop the
unnecessary "inline", and lowercase the name.
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Acked-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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EX_RDONLY is only called in one place; just put it there.
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Acked-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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page-writeback accounting is presently performed in the page-flags macros.
This is inconsistent and a bit ugly and makes it awkward to implement
per-backing_dev under-writeback page accounting.
So move this accounting down to the callsite(s).
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Remove is_in_rom() function. It doesn't actually serve the purpose it was
intended to. If you look at the use of it _access_ok() (which is the only use
of it) then it is obvious that most of memory is marked as access_ok. No
point having is_in_rom() then, so remove it.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Change the m68knommu irq handling to use the generic irq framework.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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The print_stack_trace macro in stacktrace.h has a wrong number of
arguments, fix it.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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__acquire
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lock _____
| \
| __contended
| |
| wait
| _______/
|/
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__acquired
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__release
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unlock
We measure acquisition and contention bouncing.
This is done by recording a cpu stamp in each lock instance.
Contention bouncing requires the cpu stamp to be set on acquisition. Hence we
move __acquired into the generic path.
__acquired is then used to measure acquisition bouncing by comparing the
current cpu with the old stamp before replacing it.
__contended is used to measure contention bouncing (only useful for preemptable
locks)
[akpm@linux-foundation.org: cleanups]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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- update the copyright notices
- use the default hash function
- fix a thinko in a BUILD_BUG_ON
- add a WARN_ON to spot inconsitent naming
- fix a termination issue in /proc/lock_stat
[akpm@linux-foundation.org: cleanups]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Introduce the core lock statistics code.
Lock statistics provides lock wait-time and hold-time (as well as the count
of corresponding contention and acquisitions events). Also, the first few
call-sites that encounter contention are tracked.
Lock wait-time is the time spent waiting on the lock. This provides insight
into the locking scheme, that is, a heavily contended lock is indicative of
a too coarse locking scheme.
Lock hold-time is the duration the lock was held, this provides a reference for
the wait-time numbers, so they can be put into perspective.
1)
lock
2)
... do stuff ..
unlock
3)
The time between 1 and 2 is the wait-time. The time between 2 and 3 is the
hold-time.
The lockdep held-lock tracking code is reused, because it already collects locks
into meaningful groups (classes), and because it is an existing infrastructure
for lock instrumentation.
Currently lockdep tracks lock acquisition with two hooks:
lock()
lock_acquire()
_lock()
... code protected by lock ...
unlock()
lock_release()
_unlock()
We need to extend this with two more hooks, in order to measure contention.
lock_contended() - used to measure contention events
lock_acquired() - completion of the contention
These are then placed the following way:
lock()
lock_acquire()
if (!_try_lock())
lock_contended()
_lock()
lock_acquired()
... do locked stuff ...
unlock()
lock_release()
_unlock()
(Note: the try_lock() 'trick' is used to avoid instrumenting all platform
dependent lock primitive implementations.)
It is also possible to toggle the two lockdep features at runtime using:
/proc/sys/kernel/prove_locking
/proc/sys/kernel/lock_stat
(esp. turning off the O(n^2) prove_locking functionaliy can help)
[akpm@linux-foundation.org: build fixes]
[akpm@linux-foundation.org: nuke unneeded ifdefs]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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