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* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next-2.6Linus Torvalds2008-12-301-2/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next-2.6: (98 commits) sparc: move select of ARCH_SUPPORTS_MSI sparc: drop SUN_IO sparc: unify sections.h sparc: use .data.init_task section for init_thread_union sparc: fix array overrun check in of_device_64.c sparc: unify module.c sparc64: prepare module_64.c for unification sparc64: use bit neutral Elf symbols sparc: unify module.h sparc: introduce CONFIG_BITS sparc: fix hardirq.h removal fallout sparc64: do not export pus_fs_struct sparc: use sparc64 version of scatterlist.h sparc: Commonize memcmp assembler. sparc: Unify strlen assembler. sparc: Add asm/asm.h sparc: Kill memcmp_32.S code which has been ifdef'd out for centuries. sparc: replace for_each_cpu_mask_nr with for_each_cpu sparc: fix sparse warnings in irq_32.c sparc: add include guards to kernel.h ...
| * Merge branch 'master' of ↵David S. Miller2008-12-28177-1970/+4880
| |\ | | | | | | | | | | | | | | | | | | master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6 Conflicts: arch/sparc64/kernel/idprom.c
| * | of: Fix comment, sparc no longer uses of_device objects on special busses.David S. Miller2008-12-041-2/+1
| | | | | | | | | | | | | | | | | | It only uses of_platform_bus_type. Signed-off-by: David S. Miller <davem@davemloft.net>
* | | Merge branch 'for-2.6.29' of git://git.kernel.dk/linux-2.6-blockLinus Torvalds2008-12-308-40/+69
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'for-2.6.29' of git://git.kernel.dk/linux-2.6-block: (43 commits) bio: get rid of bio_vec clearing bounce: don't rely on a zeroed bio_vec list cciss: simplify parameters to deregister_disk function cfq-iosched: fix race between exiting queue and exiting task loop: Do not call loop_unplug for not configured loop device. loop: Flush possible running bios when loop device is released. alpha: remove dead BIO_VMERGE_BOUNDARY Get rid of CONFIG_LSF block: make blk_softirq_init() static block: use min_not_zero in blk_queue_stack_limits block: add one-hit cache for disk partition lookup cfq-iosched: remove limit of dispatch depth of max 4 times quantum nbd: tell the block layer that it is not a rotational device block: get rid of elevator_t typedef aio: make the lookup_ioctx() lockless bio: add support for inlining a number of bio_vecs inside the bio bio: allow individual slabs in the bio_set bio: move the slab pointer inside the bio_set bio: only mempool back the largest bio_vec slab cache block: don't use plugging on SSD devices ...
| * | | Get rid of CONFIG_LSFJens Axboe2008-12-291-8/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have two seperate config entries for large devices/files. One is CONFIG_LBD that guards just the devices, the other is CONFIG_LSF that handles large files. This doesn't make a lot of sense, you typically want both or none. So get rid of CONFIG_LSF and change CONFIG_LBD wording to indicate that it covers both. Acked-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * | | block: add one-hit cache for disk partition lookupJens Axboe2008-12-291-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | disk_map_sector_rcu() returns a partition from a sector offset, which we use for IO statistics on a per-partition basis. The lookup itself is an O(N) list lookup, where N is the number of partitions. This actually hurts performance quite a bit, even on the lower end partitions. On higher numbered partitions, it can get pretty bad. Solve this by adding a one-hit cache for partition lookup. This makes the lookup O(1) for the case where we do most IO to one partition. Even for mixed partition workloads, amortized cost is pretty close to O(1) since the natural IO batching makes the one-hit cache last for lots of IOs. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * | | block: get rid of elevator_t typedefJens Axboe2008-12-292-6/+5
| | | | | | | | | | | | | | | | | | | | | | | | Just use struct elevator_queue everywhere instead. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * | | aio: make the lookup_ioctx() locklessJens Axboe2008-12-292-3/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The mm->ioctx_list is currently protected by a reader-writer lock, so we always grab that lock on the read side for doing ioctx lookups. As the workload is extremely reader biased, turn this into an rcu hlist so we can make lookup_ioctx() lockless. Get rid of the rwlock and use a spinlock for providing update side exclusion. There's usually only 1 entry on this list, so it doesn't make sense to look into fancier data structures. Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * | | bio: add support for inlining a number of bio_vecs inside the bioJens Axboe2008-12-291-0/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we go and allocate a bio for IO, we actually do two allocations. One for the bio itself, and one for the bi_io_vec that holds the actual pages we are interested in. This feature inlines a definable amount of io vecs inside the bio itself, so we eliminate the bio_vec array allocation for IO's up to a certain size. It defaults to 4 vecs, which is typically 16k of IO. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * | | bio: allow individual slabs in the bio_setJens Axboe2008-12-291-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Instead of having a global bio slab cache, add a reference to one in each bio_set that is created. This allows for personalized slabs in each bio_set, so that they can have bios of different sizes. This means we can personalize the bios we return. File systems may want to embed the bio inside another structure, to avoid allocation more items (and stuffing them in ->bi_private) after the get a bio. Or we may want to embed a number of bio_vecs directly at the end of a bio, to avoid doing two allocations to return a bio. This is now possible. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * | | bio: move the slab pointer inside the bio_setJens Axboe2008-12-291-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | In preparation for adding differently sized bios. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * | | bio: only mempool back the largest bio_vec slab cacheJens Axboe2008-12-291-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We only very rarely need the mempool backing, so it makes sense to get rid of all but one of the mempool in a bio_set. So keep the largest bio_vec count mempool so we can always honor the largest allocation, and "upgrade" callers that fail. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * | | block: simplify empty barrier implementationTejun Heo2008-12-291-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Empty barrier required special handling in __elv_next_request() to complete it without letting the low level driver see it. With previous changes, barrier code is now flexible enough to skip the BAR step using the same barrier sequence selection mechanism. Drop the special handling and mask off q->ordered from start_ordered(). Remove blk_empty_barrier() test which now has no user. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * | | block: make barrier completion more robustTejun Heo2008-12-291-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Barrier completion had the following assumptions. * start_ordered() couldn't finish the whole sequence properly. If all actions are to be skipped, q->ordseq is set correctly but the actual completion was never triggered thus hanging the barrier request. * Drain completion in elv_complete_request() assumed that there's always at least one request in the queue when drain completes. Both assumptions are true but these assumptions need to be removed to improve empty barrier implementation. This patch makes the following changes. * Make start_ordered() use blk_ordered_complete_seq() to mark skipped steps complete and notify __elv_next_request() that it should fetch the next request if the whole barrier has completed inside start_ordered(). * Make drain completion path in elv_complete_request() check whether the queue is empty. Empty queue also indicates drain completion. * While at it, convert 0/1 return from blk_do_ordered() to false/true. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * | | block: make every barrier action optionalTejun Heo2008-12-291-2/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In all barrier sequences, the barrier write itself was always assumed to be issued and thus didn't have corresponding control flag. This patch adds QUEUE_ORDERED_DO_BAR and unify action mask handling in start_ordered() such that any barrier action can be skipped. This patch doesn't introduce any visible behavior changes. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * | | block: reorganize QUEUE_ORDERED_* constantsTejun Heo2008-12-291-16/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Separate out ordering type (drain,) and action masks (preflush, postflush, fua) from visible ordering mode selectors (QUEUE_ORDERED_*). Ordering types are now named QUEUE_ORDERED_BY_* while action masks are named QUEUE_ORDERED_DO_*. This change is necessary to add QUEUE_ORDERED_DO_BAR and make it optional to improve empty barrier implementation. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * | | block: reorder struct bio to remove padding on 64bitRichard Kennedy2008-12-291-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove 8 bytes of padding from struct bio which also removes 16 bytes from struct bio_pair to make it 248 bytes. bio_pair then fits into one fewer cache lines & into a smaller slab. Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * | | block: use cancel_work_sync() instead of kblockd_flush_work()Cheng Renquan2008-12-291-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After many improvements on kblockd_flush_work, it is now identical to cancel_work_sync, so a direct call to cancel_work_sync is suggested. The only difference is that cancel_work_sync is a GPL symbol, so no non-GPL modules anymore. Signed-off-by: Cheng Renquan <crquan@gmail.com> Cc: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * | | block: Supress Buffer I/O errors when SCSI REQ_QUIET flag setKeith Mannthey2008-12-292-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Allow the scsi request REQ_QUIET flag to be propagated to the buffer file system layer. The basic ideas is to pass the flag from the scsi request to the bio (block IO) and then to the buffer layer. The buffer layer can then suppress needless printks. This patch declutters the kernel log by removed the 40-50 (per lun) buffer io error messages seen during a boot in my multipath setup . It is a good chance any real errors will be missed in the "noise" it the logs without this patch. During boot I see blocks of messages like " __ratelimit: 211 callbacks suppressed Buffer I/O error on device sdm, logical block 5242879 Buffer I/O error on device sdm, logical block 5242879 Buffer I/O error on device sdm, logical block 5242847 Buffer I/O error on device sdm, logical block 1 Buffer I/O error on device sdm, logical block 5242878 Buffer I/O error on device sdm, logical block 5242879 Buffer I/O error on device sdm, logical block 5242879 Buffer I/O error on device sdm, logical block 5242879 Buffer I/O error on device sdm, logical block 5242879 Buffer I/O error on device sdm, logical block 5242872 " in my logs. My disk environment is multipath fiber channel using the SCSI_DH_RDAC code and multipathd. This topology includes an "active" and "ghost" path for each lun. IO's to the "ghost" path will never complete and the SCSI layer, via the scsi device handler rdac code, quick returns the IOs to theses paths and sets the REQ_QUIET scsi flag to suppress the scsi layer messages. I am wanting to extend the QUIET behavior to include the buffer file system layer to deal with these errors as well. I have been running this patch for a while now on several boxes without issue. A few runs of bonnie++ show no noticeable difference in performance in my setup. Thanks for John Stultz for the quiet_error finalization. Submitted-by: Keith Mannthey <kmannth@us.ibm.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * | | block: add queue flag for paravirt frontend driversFernando Luis Vázquez Cao2008-12-291-0/+1
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | As is the case with SSD devices, we do not want to idle in AS/CFQ when the block device is a paravirt front-end driver. This patch adds a flag (QUEUE_FLAG_VIRT) which should be used by front-end drivers such as virtio_blk and xen-blkfront to indicate a paravirtualized device. Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* | | Merge branch 'irq-core-for-linus' of ↵Linus Torvalds2008-12-308-11/+150
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, sparseirq: clean up Kconfig entry x86: turn CONFIG_SPARSE_IRQ off by default sparseirq: fix numa_migrate_irq_desc dependency and comments sparseirq: add kernel-doc notation for new member in irq_desc, -v2 locking, irq: enclose irq_desc_lock_class in CONFIG_LOCKDEP sparseirq, xen: make sure irq_desc is allocated for interrupts sparseirq: fix !SMP building, #2 x86, sparseirq: move irq_desc according to smp_affinity, v7 proc: enclose desc variable of show_stat() in CONFIG_SPARSE_IRQ sparse irqs: add irqnr.h to the user headers list sparse irqs: handle !GENIRQ platforms sparseirq: fix !SMP && !PCI_MSI && !HT_IRQ build sparseirq: fix Alpha build failure sparseirq: fix typo in !CONFIG_IO_APIC case x86, MSI: pass irq_cfg and irq_desc x86: MSI start irq numbering from nr_irqs_gsi x86: use NR_IRQS_LEGACY sparse irq_desc[] array: core kernel and x86 changes genirq: record IRQ_LEVEL in irq_desc[] irq.h: remove padding from irq_desc on 64bits
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| *---. \ \ Merge branches 'irq/sparseirq', 'irq/genirq' and 'irq/urgent'; commit ↵Ingo Molnar2008-12-2541-76/+251
| |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | 'v2.6.28' into irq/core
| | * | | | | sparseirq: add kernel-doc notation for new member in irq_desc, -v2Yinghai Lu2008-12-191-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Yinghai Lu <yinghai@kernel.org> Acked-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | | locking, irq: enclose irq_desc_lock_class in CONFIG_LOCKDEPKOSAKI Motohiro2008-12-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: simplify code commit "08678b0: generic: sparse irqs: use irq_desc() [...]" introduced the irq_desc_lock_class variable. But it is used only if CONFIG_SPARSE_IRQ=Y or CONFIG_TRACE_IRQFLAGS=Y. Otherwise, following warnings happen: CC kernel/irq/handle.o kernel/irq/handle.c:26: warning: 'irq_desc_lock_class' defined but not used Actually, current early_init_irq_lock_class has a bit strange and messy ifdef. In addition, it is not valueable. 1. this function is protected by !CONFIG_SPARSE_IRQ, but that is not necessary. if CONFIG_SPARSE_IRQ=Y, desc of all irq number are initialized by NULL at first - then this function calling is safe. 2. this function protected by CONFIG_TRACE_IRQFLAGS too. but it is not necessary either, because lockdep_set_class() doesn't have bad side effect even if CONFIG_TRACE_IRQFLAGS=n. This patch bloat kernel size a bit on CONFIG_TRACE_IRQFLAGS=n and CONFIG_SPARSE_IRQ=Y - but that's ok. early_init_irq_lock_class() is not a fastpatch at all. To avoid messy ifdefs is more important than a few bytes diet. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | | x86, sparseirq: move irq_desc according to smp_affinity, v7Yinghai Lu2008-12-171-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: improve NUMA handling by migrating irq_desc on smp_affinity changes if CONFIG_NUMA_MIGRATE_IRQ_DESC is set: - make irq_desc to go with affinity aka irq_desc moving etc - call move_irq_desc in irq_complete_move() - legacy irq_desc is not moved, because they are allocated via static array for logical apic mode, need to add move_desc_in_progress_in_same_domain, otherwise it will not be moved ==> also could need two phases to get irq_desc moved. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | | sparse irqs: add irqnr.h to the user headers listIngo Molnar2008-12-121-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix build error /home/mingo/tip/usr/include/linux/random.h:11: included file 'linux/irqnr.h' is not exported Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | | sparse irqs: handle !GENIRQ platformsIngo Molnar2008-12-123-4/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: build fix fix: In file included from /home/mingo/tip/arch/m68k/amiga/amiints.c:39: /home/mingo/tip/include/linux/interrupt.h:21: error: expected identifier or '(' /home/mingo/tip/arch/m68k/amiga/amiints.c: In function 'amiga_init_IRQ': Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | | sparseirq: fix Alpha build failureYinghai Lu2008-12-092-12/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: build fix on Alpha -tip testing found this build failure on the Alpha defconfig: /home/mingo/tip/fs/proc/stat.c: In function 'show_stat': /home/mingo/tip/fs/proc/stat.c:48: error: implicit declaration of function 'for_each_irq_desc' /home/mingo/tip/fs/proc/stat.c:48: error: expected ';' before '{' token can not use irq_desc() in stat.c on older architectures. Signed-off-by: Yinghai Lu <yinghai@kernel.orgg> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | | x86, MSI: pass irq_cfg and irq_descYinghai Lu2008-12-081-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: simplify code Pass irq_desc and cfg around, instead of raw IRQ numbers - this way we dont have to look it up again and again. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | | | sparse irq_desc[] array: core kernel and x86 changesYinghai Lu2008-12-085-13/+122
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: new feature Problem on distro kernels: irq_desc[NR_IRQS] takes megabytes of RAM with NR_CPUS set to large values. The goal is to be able to scale up to much larger NR_IRQS value without impacting the (important) common case. To solve this, we generalize irq_desc[NR_IRQS] to an (optional) array of irq_desc pointers. When CONFIG_SPARSE_IRQ=y is used, we use kzalloc_node to get irq_desc, this also makes the IRQ descriptors NUMA-local (to the site that calls request_irq()). This gets rid of the irq_cfg[] static array on x86 as well: irq_cfg now uses desc->chip_data for x86 to store irq_cfg. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | | irq.h: remove padding from irq_desc on 64bitsRichard Kennedy2008-11-231-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: reduce struct irq_desc size struct irq_desc: reorder to remove padding on 64bits shrinks irq_desc to 128 bytes which saves data space & cache lines On a generic x86_64/SMP build this reduces the reported data size by 64k. Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | | | | | Merge branch 'timers-core-for-linus' of ↵Linus Torvalds2008-12-304-72/+44
|\ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: hrtimers: fix warning in kernel/hrtimer.c x86: make sure we really have an hpet mapping before using it x86: enable HPET on Fujitsu u9200 linux/timex.h: cleanup for userspace posix-timers: simplify de_thread()->exit_itimers() path posix-timers: check ->it_signal instead of ->it_pid to validate the timer posix-timers: use "struct pid*" instead of "struct task_struct*" nohz: suppress needless timer reprogramming clocksource, acpi_pm.c: put acpi_pm_read_slow() under CONFIG_PCI nohz: no softirq pending warnings for offline cpus hrtimer: removing all ur callback modes, fix hrtimer: removing all ur callback modes, fix hotplug hrtimer: removing all ur callback modes x86: correct link to HPET timer specification rtc-cmos: export second NVRAM bank Fixed up conflicts in sound/drivers/pcsp/pcsp.c and sound/core/hrtimer.c manually.
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| *---------. \ \ \ \ \ \ Merge branches 'timers/clocksource', 'timers/hpet', 'timers/hrtimers', ↵Ingo Molnar2008-12-254-72/+44
| |\ \ \ \ \ \ \ \ \ \ \ \ | | | | |_|_|_|/ / / / / / | | | |/| | | | | | / / / | | |_|_|_|_|_|_|_|/ / / | |/| | | | | | | | | | 'timers/nohz', 'timers/ntp', 'timers/posixtimers' and 'timers/rtc' into timers/core
| | | | | | * | | | | | posix-timers: use "struct pid*" instead of "struct task_struct*"Oleg Nesterov2008-12-121-1/+5
| | | |_|_|/ / / / / / | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: restructure, clean up code k_itimer holds the ref to the ->it_process until sys_timer_delete(). This allows to pin up to RLIMIT_SIGPENDING dead task_struct's. Change the code to use "struct pid *" instead. The patch doesn't kill ->it_process, it places ->it_pid into the union. ->it_process is still used by do_cpu_nanosleep() as before. It would be trivial to change the nanosleep code as well, but since it uses it_process in a special way I think it is better to keep this field for grep. The patch bloats the kernel by 104 bytes and it also adds the new pointer, ->it_signal, to k_itimer. It is used by lock_timer() to verify that the found timer was not created by another process. It is not clear why do we use the global database (and thus the global idr_lock) for posix timers. We still need the signal_struct->posix_timers which contains all useable timers, perhaps it is better to use some form of per-process array instead. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | | | | * | | | | | linux/timex.h: cleanup for userspaceMike Frysinger2008-12-121-36/+37
| | | |_|/ / / / / / | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix user-space exported use Move all the kernel-specific defines and includes into the __KERNEL__ section so that they don't get leaked into userspace. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | | | * | | | | | hrtimer: removing all ur callback modesPeter Zijlstra2008-11-252-35/+2
| | | |/ / / / / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: cleanup, move all hrtimer processing into hardirq context This is an attempt at removing some of the hrtimer complexity by reducing the number of callback modes to 1. This means that all hrtimer callback functions will be ran from HARD-irq context. I went through all the 30 odd hrtimer callback functions in the kernel and saw only one that I'm not quite sure of, which is the one in net/can/bcm.c - hence I'm CC-ing the folks responsible for that code. Furthermore, the hrtimer core now calls callbacks directly with IRQs disabled in case you try to enqueue an expired timer. If this timer is a periodic timer (which should use hrtimer_forward() to advance its time) then it might be possible to end up in an inf. recursive loop due to the fact that hrtimer_forward() doesn't round up to the next timer granularity, and therefore keeps on calling the callback - obviously this needs a fix. Aside from that, this seems to compile and actually boot on my dual core test box - although I'm sure there are some bugs in, me not hitting any makes me certain :-) Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | | | | | | | Merge branch 'core-for-linus' of ↵Linus Torvalds2008-12-3013-22/+427
|\ \ \ \ \ \ \ \ \ | |_|_|_|_|_|_|/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (63 commits) stacktrace: provide save_stack_trace_tsk() weak alias rcu: provide RCU options on non-preempt architectures too printk: fix discarding message when recursion_bug futex: clean up futex_(un)lock_pi fault handling "Tree RCU": scalable classic RCU implementation futex: rename field in futex_q to clarify single waiter semantics x86/swiotlb: add default swiotlb_arch_range_needs_mapping x86/swiotlb: add default phys<->bus conversion x86: unify pci iommu setup and allow swiotlb to compile for 32 bit x86: add swiotlb allocation functions swiotlb: consolidate swiotlb info message printing swiotlb: support bouncing of HighMem pages swiotlb: factor out copy to/from device swiotlb: add arch hook to force mapping swiotlb: allow architectures to override phys<->bus<->phys conversions swiotlb: add comment where we handle the overflow of a dma mask on 32 bit rcu: fix rcutorture behavior during reboot resources: skip sanity check of busy resources swiotlb: move some definitions to header swiotlb: allow architectures to override swiotlb pool allocation ... Fix up trivial conflicts in arch/x86/kernel/Makefile arch/x86/mm/init_32.c include/linux/hardirq.h as per Ingo's suggestions.
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| *-------------. \ \ \ \ \ \ \ Merge branches 'core/debugobjects', 'core/iommu', 'core/locking', ↵Ingo Molnar2008-12-256-12/+376
| |\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ | | | | | | | | | |/ / / / / / / | | | | | | | | | | | / / / / / | | | |_|_|_|_|_|_|_|/ / / / / | | |/| | | | | | | | | | | | 'core/printk', 'core/rcu', 'core/resources', 'core/softirq' and 'core/stacktrace' into core/core
| | | | | | | | * | | | | | | softirq: remove useless function __local_bh_enableLiming Wang2008-11-281-1/+0
| | | |_|_|_|_|/ / / / / / / | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: remove unused code __local_bh_enable has been replaced with _local_bh_enable. As comments says "it always nests inside local_bh_enable() sections" has not been valid now. Also there is no reason to use __local_bh_enable anywhere, so we can remove this useless function. Signed-off-by: Liming Wang <liming.wang@windriver.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | | | | | * | | | | | | | "Tree RCU": scalable classic RCU implementationPaul E. McKenney2008-12-183-9/+344
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes a long-standing performance bug in classic RCU that results in massive internal-to-RCU lock contention on systems with more than a few hundred CPUs. Although this patch creates a separate flavor of RCU for ease of review and patch maintenance, it is intended to replace classic RCU. This patch still handles stress better than does mainline, so I am still calling it ready for inclusion. This patch is against the -tip tree. Nevertheless, experience on an actual 1000+ CPU machine would still be most welcome. Most of the changes noted below were found while creating an rcutiny (which should permit ejecting the current rcuclassic) and while doing detailed line-by-line documentation. Updates from v9 (http://lkml.org/lkml/2008/12/2/334): o Fixes from remainder of line-by-line code walkthrough, including comment spelling, initialization, undesirable narrowing due to type conversion, removing redundant memory barriers, removing redundant local-variable initialization, and removing redundant local variables. I do not believe that any of these fixes address the CPU-hotplug issues that Andi Kleen was seeing, but please do give it a whirl in case the machine is smarter than I am. A writeup from the walkthrough may be found at the following URL, in case you are suffering from terminal insomnia or masochism: http://www.kernel.org/pub/linux/kernel/people/paulmck/tmp/rcutree-walkthrough.2008.12.16a.pdf o Made rcutree tracing use seq_file, as suggested some time ago by Lai Jiangshan. o Added a .csv variant of the rcudata debugfs trace file, to allow people having thousands of CPUs to drop the data into a spreadsheet. Tested with oocalc and gnumeric. Updated documentation to suit. Updates from v8 (http://lkml.org/lkml/2008/11/15/139): o Fix a theoretical race between grace-period initialization and force_quiescent_state() that could occur if more than three jiffies were required to carry out the grace-period initialization. Which it might, if you had enough CPUs. o Apply Ingo's printk-standardization patch. o Substitute local variables for repeated accesses to global variables. o Fix comment misspellings and redundant (but harmless) increments of ->n_rcu_pending (this latter after having explicitly added it). o Apply checkpatch fixes. Updates from v7 (http://lkml.org/lkml/2008/10/10/291): o Fixed a number of problems noted by Gautham Shenoy, including the cpu-stall-detection bug that he was having difficulty convincing me was real. ;-) o Changed cpu-stall detection to wait for ten seconds rather than three in order to reduce false positive, as suggested by Ingo Molnar. o Produced a design document (http://lwn.net/Articles/305782/). The act of writing this document uncovered a number of both theoretical and "here and now" bugs as noted below. o Fix dynticks_nesting accounting confusion, simplify WARN_ON() condition, fix kerneldoc comments, and add memory barriers in dynticks interface functions. o Add more data to tracing. o Remove unused "rcu_barrier" field from rcu_data structure. o Count calls to rcu_pending() from scheduling-clock interrupt to use as a surrogate timebase should jiffies stop counting. o Fix a theoretical race between force_quiescent_state() and grace-period initialization. Yes, initialization does have to go on for some jiffies for this race to occur, but given enough CPUs... Updates from v6 (http://lkml.org/lkml/2008/9/23/448): o Fix a number of checkpatch.pl complaints. o Apply review comments from Ingo Molnar and Lai Jiangshan on the stall-detection code. o Fix several bugs in !CONFIG_SMP builds. o Fix a misspelled config-parameter name so that RCU now announces at boot time if stall detection is configured. o Run tests on numerous combinations of configurations parameters, which after the fixes above, now build and run correctly. Updates from v5 (http://lkml.org/lkml/2008/9/15/92, bad subject line): o Fix a compiler error in the !CONFIG_FANOUT_EXACT case (blew a changeset some time ago, and finally got around to retesting this option). o Fix some tracing bugs in rcupreempt that caused incorrect totals to be printed. o I now test with a more brutal random-selection online/offline script (attached). Probably more brutal than it needs to be on the people reading it as well, but so it goes. o A number of optimizations and usability improvements: o Make rcu_pending() ignore the grace-period timeout when there is no grace period in progress. o Make force_quiescent_state() avoid going for a global lock in the case where there is no grace period in progress. o Rearrange struct fields to improve struct layout. o Make call_rcu() initiate a grace period if RCU was idle, rather than waiting for the next scheduling clock interrupt. o Invoke rcu_irq_enter() and rcu_irq_exit() only when idle, as suggested by Andi Kleen. I still don't completely trust this change, and might back it out. o Make CONFIG_RCU_TRACE be the single config variable manipulated for all forms of RCU, instead of the prior confusion. o Document tracing files and formats for both rcupreempt and rcutree. Updates from v4 for those missing v5 given its bad subject line: o Separated dynticks interface so that NMIs and irqs call separate functions, greatly simplifying it. In particular, this code no longer requires a proof of correctness. ;-) o Separated dynticks state out into its own per-CPU structure, avoiding the duplicated accounting. o The case where a dynticks-idle CPU runs an irq handler that invokes call_rcu() is now correctly handled, forcing that CPU out of dynticks-idle mode. o Review comments have been applied (thank you all!!!). For but one example, fixed the dynticks-ordering issue that Manfred pointed out, saving me much debugging. ;-) o Adjusted rcuclassic and rcupreempt to handle dynticks changes. Attached is an updated patch to Classic RCU that applies a hierarchy, greatly reducing the contention on the top-level lock for large machines. This passes 10-hour concurrent rcutorture and online-offline testing on 128-CPU ppc64 without dynticks enabled, and exposes some timekeeping bugs in presence of dynticks (exciting working on a system where "sleep 1" hangs until interrupted...), which were fixed in the 2.6.27 kernel. It is getting more reliable than mainline by some measures, so the next version will be against -tip for inclusion. See also Manfred Spraul's recent patches (or his earlier work from 2004 at http://marc.info/?l=linux-kernel&m=108546384711797&w=2). We will converge onto a common patch in the fullness of time, but are currently exploring different regions of the design space. That said, I have already gratefully stolen quite a few of Manfred's ideas. This patch provides CONFIG_RCU_FANOUT, which controls the bushiness of the RCU hierarchy. Defaults to 32 on 32-bit machines and 64 on 64-bit machines. If CONFIG_NR_CPUS is less than CONFIG_RCU_FANOUT, there is no hierarchy. By default, the RCU initialization code will adjust CONFIG_RCU_FANOUT to balance the hierarchy, so strongly NUMA architectures may choose to set CONFIG_RCU_FANOUT_EXACT to disable this balancing, allowing the hierarchy to be exactly aligned to the underlying hardware. Up to two levels of hierarchy are permitted (in addition to the root node), allowing up to 16,384 CPUs on 32-bit systems and up to 262,144 CPUs on 64-bit systems. I just know that I am going to regret saying this, but this seems more than sufficient for the foreseeable future. (Some architectures might wish to set CONFIG_RCU_FANOUT=4, which would limit such architectures to 64 CPUs. If this becomes a real problem, additional levels can be added, but I doubt that it will make a significant difference on real hardware.) In the common case, a given CPU will manipulate its private rcu_data structure and the rcu_node structure that it shares with its immediate neighbors. This can reduce both lock and memory contention by multiple orders of magnitude, which should eliminate the need for the strange manipulations that are reported to be required when running Linux on very large systems. Some shortcomings: o More bugs will probably surface as a result of an ongoing line-by-line code inspection. Patches will be provided as required. o There are probably hangs, rcutorture failures, &c. Seems quite stable on a 128-CPU machine, but that is kind of small compared to 4096 CPUs. However, seems to do better than mainline. Patches will be provided as required. o The memory footprint of this version is several KB larger than rcuclassic. A separate UP-only rcutiny patch will be provided, which will reduce the memory footprint significantly, even compared to the old rcuclassic. One such patch passes light testing, and has a memory footprint smaller even than rcuclassic. Initial reaction from various embedded guys was "it is not worth it", so am putting it aside. Credits: o Manfred Spraul for ideas, review comments, and bugs spotted, as well as some good friendly competition. ;-) o Josh Triplett, Ingo Molnar, Peter Zijlstra, Mathieu Desnoyers, Lai Jiangshan, Andi Kleen, Andy Whitcroft, and Andrew Morton for reviews and comments. o Thomas Gleixner for much-needed help with some timer issues (see patches below). o Jon M. Tollefson, Tim Pepper, Andrew Theurer, Jose R. Santos, Andy Whitcroft, Darrick Wong, Nishanth Aravamudan, Anton Blanchard, Dave Kleikamp, and Nathan Lynch for keeping machines alive despite my heavy abuse^Wtesting. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | | | | | * | | | | | | | Merge branch 'linus' into core/rcuIngo Molnar2008-12-1875-483/+1161
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| | | | * | | | | | | | | | | lockdep: change a held lock's classPeter Zijlstra2008-12-041-2/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: introduce new lockdep API Allow to change a held lock's class. Basically the same as the existing code to change a subclass therefore reuse all that. The XFS code will be able to use this to annotate their inode locking. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | | | * | | | | | | | | | | Merge commit 'v2.6.28-rc7' into core/lockingIngo Molnar2008-12-0434-120/+231
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| | | * | | | | | | | | | | | swiotlb: add arch hook to force mappingIan Campbell2008-12-171-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: generalize the sw-IOTLB range checks Some architectures require special rules to determine whether a range needs mapping or not. This adds a weak function for architectures to override. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | | * | | | | | | | | | | | swiotlb: allow architectures to override phys<->bus<->phys conversionsIan Campbell2008-12-171-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: generalize phys<->bus<->phys conversions in the swiotlb code Architectures may need to override these conversions. Implement a __weak hook point containing the default implementation. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | | * | | | | | | | | | | | swiotlb: move some definitions to headerIan Campbell2008-12-161-0/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: cleanup Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | | * | | | | | | | | | | | swiotlb: allow architectures to override swiotlb pool allocationJeremy Fitzhardinge2008-12-161-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: generalize swiotlb allocation code Architectures may need to allocate memory specially for use with the swiotlb. Create the weak function swiotlb_alloc_boot() and swiotlb_alloc() defaulting to the current behaviour. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | | | | | | | | | | Merge branch 'core/futexes' into core/coreIngo Molnar2008-12-251-1/+2
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| | * | | | | | | | | | | | | | futex: make clock selectable for FUTEX_WAIT_BITSETThomas Gleixner2008-11-241-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | FUTEX_WAIT_BITSET could be used instead of FUTEX_WAIT by setting the bit set to FUTEX_BITSET_MATCH_ANY, but FUTEX_WAIT uses CLOCK_REALTIME while FUTEX_WAIT_BITSET uses CLOCK_MONOTONIC. Add a flag to select CLOCK_REALTIME for FUTEX_WAIT_BITSET so glibc can replace the FUTEX_WAIT logic which needs to do gettimeofday() calls before and after the syscall to convert the absolute timeout to a relative timeout for FUTEX_WAIT. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Ulrich Drepper <drepper@redhat.com>
| | * | | | | | | | | | | | | | Merge branch 'linus' into core/futexesThomas Gleixner2008-11-241897-184266/+23833
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