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2005-08-24[ACPI] delete CONFIG_ACPI_BOOTLen Brown
it has been a synonym for CONFIG_ACPI since 2.6.12 Signed-off-by: Len Brown <len.brown@intel.com>
2005-08-23Merge from-linus to-akpmLen Brown
2005-08-19Fix nasty ncpfs symlink handling bug.Linus Torvalds
This bug could cause oopses and page state corruption, because ncpfs used the generic page-cache symlink handlign functions. But those functions only work if the page cache is guaranteed to be "stable", ie a page that was installed when the symlink walk was started has to still be installed in the page cache at the end of the walk. We could have fixed ncpfs to not use the generic helper routines, but it is in many ways much cleaner to instead improve on the symlink walking helper routines so that they don't require that absolute stability. We do this by allowing "follow_link()" to return a error-pointer as a cookie, which is fed back to the cleanup "put_link()" routine. This also simplifies NFS symlink handling. Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-18Merge master.kernel.org:/pub/scm/linux/kernel/git/bart/ide-2.6Linus Torvalds
2005-08-18[PATCH] serverworks: add support for new southbridge IDENarendra Sankar
BCM5785 (HT1000) is a Opteron Southbridge from Serverworks/Broadcom that incorporates a single channel ATA100 IDE controller that is functionally identical to the Serverworks CSB6 IDE controller. This patch adds support for the new PCI device ID and also the support for this controller. Signed-off-by: Narendra Sankar <nsankar@broadcom.com> Acked-by: Jeff Garzik <jgarzik@pobox.com> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@elka.pw.edu.pl>
2005-08-18[PATCH] ide: add support for Netcell Revolution to pci-ide generic driverMatt Gillette
Adds support for Netcell Revolution to pci-ide generic driver by including it in the list of devices matched. Includes the Revolution in the list of simplex devices forced into DMA mode. Signed-off-by: Matt Gillette <matt.gillette@netcell.com> Cc: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl> Cc: Jeff Garzik <jgarzik@pobox.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@elka.pw.edu.pl>
2005-08-18[PATCH] ide: fix PCI_DEVIEC_ID_APPLE_UNI_N_ATA spellingGrant Coady
Signed-off-by: Grant Coady <gcoady@gmail.com> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@elka.pw.edu.pl>
2005-08-18[PATCH] NFS: Introduce the use of inode->i_lock to protect fields in nfsiChuck Lever
Down the road we want to eliminate the use of the global kernel lock entirely from the NFS client. To do this, we need to protect the fields in the nfs_inode structure adequately. Start by serializing updates to the "cache_validity" field. Note this change addresses an SMP hang found by njw@osdl.org, where processes deadlock because nfs_end_data_update and nfs_revalidate_mapping update the "cache_validity" field without proper serialization. Test plan: Millions of fsx ops on SMP clients. Run Nick Wilson's breaknfs program on large SMP clients. Signed-off-by: Chuck Lever <cel@netapp.com> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-18[PATCH] NFS: use atomic bitops to manipulate flags in nfsi->flagsChuck Lever
Introduce atomic bitops to manipulate the bits in the nfs_inode structure's "flags" field. Using bitops means we can use a generic wait_on_bit call instead of an ad hoc locking scheme in fs/nfs/inode.c, so we can remove the "nfs_i_wait" field from nfs_inode at the same time. The other new flags field will continue to use bitmask and logic AND and OR. This permits several flags to be set at the same time efficiently. The following patch adds a spin lock to protect these flags, and this spin lock will later cover other fields in the nfs_inode structure, amortizing the cost of using this type of serialization. Test plan: Millions of fsx ops on SMP clients. Signed-off-by: Chuck Lever <cel@netapp.com> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-18[PATCH] NFS: split nfsi->flags into two fieldsChuck Lever
Certain bits in nfsi->flags can be manipulated with atomic bitops, and some are better manipulated via logical bitmask operations. This patch splits the flags field into two. The next patch introduces atomic bitops for one of the fields. Test plan: Millions of fsx ops on SMP clients. Signed-off-by: Chuck Lever <cel@netapp.com> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-16[PATCH] PCI: 6700/6702PXH quirkKristen Accardi
On the 6700/6702 PXH part, a MSI may get corrupted if an ACPI hotplug driver and SHPC driver in MSI mode are used together. This patch will prevent MSI from being enabled for the SHPC as part of an early pci quirk, as well as on any pci device which sets the no_msi bit. Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-16[PATCH] NFS: Ensure we always update inode->i_mode when doing O_EXCL createsTrond Myklebust
When the client performs an exclusive create and opens the file for writing, a Netapp filer will first create the file using the mode 01777. It does this since an NFSv3/v4 exclusive create cannot immediately set the mode bits. The 01777 mode then gets put into the inode->i_mode. After the file creation is successful, we then do a setattr to change the mode to the correct value (as per the NFS spec). The problem is that nfs_refresh_inode() no longer updates inode->i_mode, so the latter retains the 01777 mode. A bit later, the VFS notices this, and calls remove_suid(). This of course now resets the file mode to inode->i_mode & 0777. Hey presto, the file mode on the server is now magically changed to 0777. Duh... Fixes http://bugzilla.linux-nfs.org/show_bug.cgi?id=32 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-16[PATCH] NFS: Ensure ACL xdr code doesn't overflow.Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-15Merge from-linus to-akpmLen Brown
2005-08-15[PATCH] inotify: add MOVE_SELF eventJohn McCutchan
This adds a MOVE_SELF event to inotify. It is sent whenever the inode you are watching is moved. We need this event so that we can catch something like this: - app1: watch /etc/mtab - app2: cp /etc/mtab /tmp/mtab-work mv /etc/mtab /etc/mtab~ mv /tmp/mtab-work /etc/mtab app1 still thinks it's watching /etc/mtab but it's actually watching /etc/mtab~. Signed-off-by: John McCutchan <ttb@tentacle.dhs.org> Signed-off-by: Robert Love <rml@novell.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-11[NETPOLL]: fix initialization/NAPI raceMatt Mackall
This fixes a race during initialization with the NAPI softirq processing by using an RCU approach. This race was discovered when refill_skbs() was added to the setup code. Signed-off-by: Matt Mackall <mpm@selenic.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-11[NETPOLL]: add retry timeoutMatt Mackall
Add limited retry logic to netpoll_send_skb Each time we attempt to send, decrement our per-device retry counter. On every successful send, we reset the counter. We delay 50us between attempts with up to 20000 retries for a total of 1 second. After we've exhausted our retries, subsequent failed attempts will try only once until reset by success. Signed-off-by: Matt Mackall <mpm@selenic.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-11[NET]: Make skb->protocol __be16Alexey Dobriyan
There are many instances of skb->protocol = htons(ETH_P_*); skb->protocol = __constant_htons(ETH_P_*); and skb->protocol = *_type_trans(...); Most of *_type_trans() are already endian-annotated, so, let's shift attention on other warnings. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-11Merge ../to-linusLen Brown
2005-08-09[PATCH] Fix ide-disk.c oops caused by hwif == NULLChristoph Lameter
1. Move hwif_to_node to ide.h 2. Use hwif_to_node in ide-disk.c Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-08[PATCH] fsnotify-cleanupsJohn McCutchan
This removes the now unused fsnotify_unlink & fsnotify_rmdir code. Compile tested. Signed-off-by: John McCutchan <ttb@tentacle.dhs.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-08Revert "[PATCH] PCI: restore BAR values..."Linus Torvalds
Revert commit fec59a711eef002d4ef9eb8de09dd0a26986eb77, which is breaking sparc64 that doesn't have a working pci_update_resource. We'll re-do this after 2.6.13 when we'll do it all properly.
2005-08-08Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6Linus Torvalds
2005-08-08[NETLINK]: Allocate and kill some netlink numbers.David S. Miller
NETLINK_ARPD is unused, allocate it to the Open-iSCSI folks. NETLINK_ROUTE6 and NETLINK_TAPBASE are no longer used, delete them. Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-08[PATCH] fsnotify_name/inoderemoveJohn McCutchan
The patch below unhooks fsnotify from vfs_unlink & vfs_rmdir. It introduces two new fsnotify calls, that are hooked in at the dcache level. This not only more closely matches how the VFS layer works, it also avoids the problem with locking and inode lifetimes. The two functions are - fsnotify_nameremove -- called when a directory entry is going away. It notifies the PARENT of the deletion. This is called from d_delete(). - inoderemove -- called when the files inode itself is going away. It notifies the inode that is being deleted. This is called from dentry_iput(). Signed-off-by: John McCutchan <ttb@tentacle.dhs.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-07[PATCH] remove linux/pagemap.h from linux/swap.hOlaf Hering
sparc can not include linux/pagemap.h because of the following circular dependency: asm-sparc/pgtable include linux/swap.h linux/swap.h include now linux/pagemap.h linux/pagemap.h include linux/mm.h linux/mm.h include asm/pgtable.h It needs to have the swp_entry_t type fully visible in pgtable.h, we can't work around this using macros. Signed-off-by: Olaf Hering <olh@suse.de> Cc: William Lee Irwin III <wli@holomorphy.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-06Add fakey 'deflateBound()' function to the in-kernel zlib routinesLinus Torvalds
It's not the real deflateBound() in newer zlib libraries, partly because the upcoming usage of it won't have the "stream" available, so we can't have the same interfaces anyway.
2005-08-05[PATCH] blk: fix tag shrinking (revive real_max_size)Tejun Heo
My patch in commit fa72b903f75e4f0f0b2c2feed093005167da4023 incorrectly removed blk_queue_tag->real_max_depth. The original resize implementation was incorrect in the following points. * actual allocation size of tag_index was shorter than real_max_size, but assumed to be of the same size, possibly causing memory access beyond the allocated area. * bits in tag_map between max_deptn and real_max_depth were initialized to 1's, making the tags permanently reserved. In an attempt to fix above two bugs, I had removed allocation optimization in init_tag_map and real_max_size. Tag map/index were allocated and freed immediately during resize. Unfortunately, I wasn't considering that tag map/index can be resized dynamically with tags beyond new_depth active. This led to accessing freed area after shrinking tags and led to the following bug reporting thread on linux-scsi. http://marc.theaimsgroup.com/?l=linux-scsi&m=112319898111885&w=2 To fix the problem, I've revived real_max_depth without allocation optimization in init_tag_map, and Andrew Vasquez confirmed that the problem was fixed. As Jens is not going to be available for a week, he asked me to make sure that this patch reaches you. http://marc.theaimsgroup.com/?l=linux-scsi&m=112325778530886&w=2 Also, a comment was added to make sure that real_max_size is needed for dynamic shrinking. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-05Merge ../from-linusLen Brown
2005-08-04[PATCH] Clean up inotify delete race fixJohn McCutchan
This avoids the whole #ifdef mess by just getting a copy of dentry->d_inode before d_delete is called - that makes the codepaths the same for the INOTIFY/DNOTIFY cases as for the regular no-notify case. I've been running this under a Gnome session for the last 10 minutes. Inotify is being used extensively. Signed-off-by: John McCutchan <ttb@tentacle.dhs.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-04[PATCH] PCI: restore BAR values after D3hot->D0 for devices that need itJohn W. Linville
Some PCI devices (e.g. 3c905B, 3c556B) lose all configuration (including BARs) when transitioning from D3hot->D0. This leaves such a device in an inaccessible state. The patch below causes the BARs to be restored when enabling such a device, so that its driver will be able to access it. The patch also adds pci_restore_bars as a new global symbol, and adds a correpsonding EXPORT_SYMBOL_GPL for that. Some firmware (e.g. Thinkpad T21) leaves devices in D3hot after a (re)boot. Most drivers call pci_enable_device very early, so devices left in D3hot that lose configuration during the D3hot->D0 transition will be inaccessible to their drivers. Drivers could be modified to account for this, but it would be difficult to know which drivers need modification. This is especially true since often many devices are covered by the same driver. It likely would be necessary to replicate code across dozens of drivers. The patch below should trigger only when transitioning from D3hot->D0 (or at boot), and only for devices that have the "no soft reset" bit cleared in the PM control register. I believe it is safe to include this patch as part of the PCI infrastructure. The cleanest implementation of pci_restore_bars was to call pci_update_resource. Unfortunately, that does not currently exist for the sparc64 architecture. The patch below includes a null implemenation of pci_update_resource for sparc64. Some have expressed interest in making general use of the the pci_restore_bars function, so that has been exported to GPL licensed modules. Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-05[ACPI] Merge acpi-2.6.12 branch into 2.6.13-rc3Len Brown
Signed-off-by: Len Brown <len.brown@intel.com>
2005-08-04[ACPI] CONFIG_ACPI=n build fixAndrew Morton
Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Len Brown <len.brown@intel.com>
2005-08-04[ACPI] acpi_register_gsi() can return errorKenji Kaneshige
Current acpi_register_gsi() function has no way to indicate errors to its callers even though acpi_register_gsi() can fail to register gsi because of some reasons (out of memory, lack of interrupt vectors, incorrect BIOS, and so on). As a result, caller of acpi_register_gsi() cannot handle the case that acpi_register_gsi() fails. I think failure of acpi_register_gsi() should be handled properly. This series of patches changes acpi_register_gsi() to return negative value on error, and also changes callers of acpi_register_gsi() to handle failure of acpi_register_gsi(). This patch changes the type of return value of acpi_register_gsi() from "unsigned int" to "int" to indicate an error. If acpi_register_gsi() fails to register gsi, it returns negative value. Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Len Brown <len.brown@intel.com>
2005-08-04[PATCH] md: make sure md bitmap updates are flushed when array is stopped.NeilBrown
The recent change to never ignore the bitmap, revealed that the bitmap isn't begin flushed properly when an array is stopped. We call bitmap_daemon_work three times as there is a three-stage pipeline for flushing updates to the bitmap file. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-03[PATCH] fix get_user_pages bugNick Piggin
Checking pte_dirty instead of pte_write in __follow_page is problematic for s390, and for copy_one_pte which leaves dirty when clearing write. So revert __follow_page to check pte_write as before, and make do_wp_page pass back a special extra VM_FAULT_WRITE bit to say it has done its full job: once get_user_pages receives this value, it no longer requires pte_write in __follow_page. But most callers of handle_mm_fault, in the various architectures, have switch statements which do not expect this new case. To avoid changing them all in a hurry, make an inline wrapper function (using the old name) that masks off the new bit, and use the extended interface with double underscores. Yes, we do have a call to do_wp_page from do_swap_page, but no need to change that: in rare case it's needed, another do_wp_page will follow. Signed-off-by: Hugh Dickins <hugh@veritas.com> [ Cleanups by Nick Piggin ] Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-01[PATCH] include/linux/dcookies.h: dummy functions must be "static inline"Adrian Bunk
We don't want these to be global functions. Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-01[PATCH] inotify: fix file deletion by rename detectionJohn McCutchan
When a file is moved over an existing file that you are watching, inotify won't send you a DELETE_SELF event and it won't unref the inode until the inotify instance is closed by the application. Signed-off-by: John McCutchan <ttb@tentacle.dhs.org> Signed-off-by: Robert Love <rml@novell.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-30merge 2.6.13-rc4 with ACPI's to-linus treeLen Brown
2005-07-29/home/lenb/src/to-linus branch 'acpi-2.6.12'Len Brown
2005-07-29[ACPI] suspend/resume ACPI PCI Interrupt LinksDavid Shaohua Li
Add reference count and disable ACPI PCI Interrupt Link when no device still uses it. Warn when drivers have not released Link at suspend time. http://bugzilla.kernel.org/show_bug.cgi?id=3469 Signed-off-by: David Shaohua Li <shaohua.li@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2005-07-29[PATCH] PCI: fix up errors after dma bursting patch and CONFIG_PCI=n -- bug?Kumar Gala
In the patch from: http://www.uwsg.iu.edu/hypermail/linux/kernel/0506.3/0985.html Is the the following line suppose inside the if CONFIG_PCI=n #define pci_dma_burst_advice(pdev, strat, strategy_parameter) do { } while (0) Signed-off-by: Kumar Gala <kumar.gala@freescale.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-29Merge master.kernel.org:/pub/scm/linux/kernel/git/dtor/inputLinus Torvalds
2005-07-28Revert broken "statement with no effect" warning fixLinus Torvalds
It may shut up gcc, but it also incorrectly changes the semantics of the smp_call_function() helpers. You can fix the warning other ways if you are interested (create another inline function that takes no arguments and returns zero), but preferably gcc just shouldn't complain about unused return values from statement expressions in the first place.
2005-07-28[PATCH] alpha: fix "statement with no effect" warningsRichard Henderson
Apparently gcc 4.0 complains about "({ 0; });", which leads to -Werror breakage in one of the alpha oprofile modules. One might could argue that this is a gcc bug, in that statement-expressions should be considered to be function-like rather than statement-like for the purposes of this warning. But it's just as easy to use an inline function in the first place, side-stepping the issue. Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27[PATCH] serial_core whitespace fixRalf Baechle
Use tabs for formatting like anywhere else in this file. Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27[PATCH] turn many #if $undefined_string into #ifdef $undefined_stringOlaf Hering
turn many #if $undefined_string into #ifdef $undefined_string to fix some warnings after -Wno-def was added to global CFLAGS Signed-off-by: Olaf Hering <olh@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27[PATCH] mbcache: Remove unused mb_cache_shrink parameterAndreas Gruenbacher
The cache parameter to mb_cache_shrink isn't used. We may as well remove it. Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27[PATCH] stale POSIX lock handlingPeter Staubach
I believe that there is a problem with the handling of POSIX locks, which the attached patch should address. The problem appears to be a race between fcntl(2) and close(2). A multithreaded application could close a file descriptor at the same time as it is trying to acquire a lock using the same file descriptor. I would suggest that that multithreaded application is not providing the proper synchronization for itself, but the OS should still behave correctly. SUS3 (Single UNIX Specification Version 3, read: POSIX) indicates that when a file descriptor is closed, that all POSIX locks on the file, owned by the process which closed the file descriptor, should be released. The trick here is when those locks are released. The current code releases all locks which exist when close is processing, but any locks in progress are handled when the last reference to the open file is released. There are three cases to consider. One is the simple case, a multithreaded (mt) process has a file open and races to close it and acquire a lock on it. In this case, the close will release one reference to the open file and when the fcntl is done, it will release the other reference. For this situation, no locks should exist on the file when both the close and fcntl operations are done. The current system will handle this case because the last reference to the open file is being released. The second case is when the mt process has dup(2)'d the file descriptor. The close will release one reference to the file and the fcntl, when done, will release another, but there will still be at least one more reference to the open file. One could argue that the existence of a lock on the file after the close has completed is okay, because it was acquired after the close operation and there is still a way for the application to release the lock on the file, using an existing file descriptor. The third case is when the mt process has forked, after opening the file and either before or after becoming an mt process. In this case, each process would hold a reference to the open file. For each process, this degenerates to first case above. However, the lock continues to exist until both processes have released their references to the open file. This lock could block other lock requests. The changes to release the lock when the last reference to the open file aren't quite right because they would allow the lock to exist as long as there was a reference to the open file. This is too long. The new proposed solution is to add support in the fcntl code path to detect a race with close and then to release the lock which was just acquired when such as race is detected. This causes locks to be released in a timely fashion and for the system to conform to the POSIX semantic specification. This was tested by instrumenting a kernel to detect the handling locks and then running a program which generates case #3 above. A dangling lock could be reliably generated. When the changes to detect the close/fcntl race were added, a dangling lock could no longer be generated. Cc: Matthew Wilcox <willy@debian.org> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27[PATCH] s390: spin lock retryMartin Schwidefsky
Split spin lock and r/w lock implementation into a single try which is done inline and an out of line function that repeatedly tries to get the lock before doing the cpu_relax(). Add a system control to set the number of retries before a cpu is yielded. The reason for the spin lock retry is that the diagnose 0x44 that is used to give up the virtual cpu is quite expensive. For spin locks that are held only for a short period of time the costs of the diagnoses outweights the savings for spin locks that are held for a longer timer. The default retry count is 1000. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>