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* Merge tag 'stable/for-linus-3.14-rc1-tag' of ↵Linus Torvalds2014-02-051-6/+9
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull Xen fixes from Konrad Rzeszutek Wilk: "Bug-fixes: - Revert "xen/grant-table: Avoid m2p_override during mapping" as it broke Xen ARM build. - Fix CR4 not being set on AP processors in Xen PVH mode" * tag 'stable/for-linus-3.14-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/pvh: set CR4 flags for APs Revert "xen/grant-table: Avoid m2p_override during mapping"
| * Revert "xen/grant-table: Avoid m2p_override during mapping"Konrad Rzeszutek Wilk2014-02-031-6/+9
| | | | | | | | | | | | | | | | | | | | This reverts commit 08ece5bb2312b4510b161a6ef6682f37f4eac8a1. As it breaks ARM builds and needs more attention on the ARM side. Acked-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | Merge git://git.infradead.org/users/willy/linux-nvmeLinus Torvalds2014-02-052-105/+652
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull NVMe driver update from Matthew Wilcox: "Looks like I missed the merge window ... but these are almost all bugfixes anyway (the ones that aren't have been baking for months)" * git://git.infradead.org/users/willy/linux-nvme: NVMe: Namespace use after free on surprise removal NVMe: Correct uses of INIT_WORK NVMe: Include device and queue numbers in interrupt name NVMe: Add a pci_driver shutdown method NVMe: Disable admin queue on init failure NVMe: Dynamically allocate partition numbers NVMe: Async IO queue deletion NVMe: Surprise removal handling NVMe: Abort timed out commands NVMe: Schedule reset for failed controllers NVMe: Device resume error handling NVMe: Cache dev->pci_dev in a local pointer NVMe: Fix lockdep warnings NVMe: compat SG_IO ioctl NVMe: remove deprecated IRQF_DISABLED NVMe: Avoid shift operation when writing cq head doorbell
| * | NVMe: Namespace use after free on surprise removalKeith Busch2014-02-021-13/+42
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | An nvme block device may have open references when the device is removed. New commands may still be sent on the removed device, so we need to ref count the opens, return errors for new commands, and not free the namespace and nvme_dev until all references are closed. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: Correct uses of INIT_WORKMatthew Wilcox2014-01-291-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | We need to initialise the work_struct when we initialise the rest of the struct nvme_dev, otherwise we'll hit a lockdep warning when we remove the device. Use PREPARE_WORK to change the function pointer instead of INIT_WORK. Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: Include device and queue numbers in interrupt nameMatthew Wilcox2014-01-271-5/+9
| | | | | | | | | | | | | | | | | | | | | On larger systems with many drives, it may help debugging to know which queue is tied to which interrupt, just by looking at /proc/interrupts. Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: Add a pci_driver shutdown methodKeith Busch2014-01-271-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | We need to shut down the device cleanly when the system is being shut down. This was in an earlier patch but was inadvertently lost during a rewrite. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: Disable admin queue on init failureKeith Busch2014-01-271-5/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | Disable the admin queue if device fails during initialization so the queue's irq is freed. Signed-off-by: Keith Busch <keith.busch@intel.com> [rewritten to use nvme_free_queues] Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: Dynamically allocate partition numbersMatthew Wilcox2014-01-271-33/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some users need more than 64 partitions per device. Rather than simply increasing the number of partitions, switch to the dynamic partition allocation scheme. This means that minor numbers are not stable across boots, but since major numbers aren't either, I cannot see this being a significant problem. Tested-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: Async IO queue deletionKeith Busch2014-01-271-12/+217
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This attempts to delete all IO queues at the same time asynchronously on shutdown. This is necessary for a present device that is not responding; a shutdown operation previously would take 2 minutes per queue-pair to timeout before moving on to the next queue, making a device removal appear to take a very long time or "hung" as reported by users. In the previous worst case, a removal may be stuck forever until a kill signal is given if there are more than 32 queue pairs since it would run out of admin command IDs after over an hour of timed out sync commands (admin queue depth is 64). This patch will wait for the admin command timeout for all commands to complete, so the worst case now for an unresponsive controller is 60 seconds, though that still seems like a long time. Since this adds another way to take queues offline, some duplicate code resulted so I moved these into more convienient functions. Signed-off-by: Keith Busch <keith.busch@intel.com> [make functions static, correct line length and whitespace issues] Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: Surprise removal handlingKeith Busch2014-01-271-3/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds checks to see if the nvme pci device was removed. The check reads the status register for the value of -1, which it should never be unless the device is no longer present. If a user performs a surprise removal on an nvme device, the driver will be notified either by the pci driver remove callback if the platform's slot is capable of this event, or via reading the device BAR status register, which will indicate controller failure and trigger a reset. Either way, the device is not present so all outstanding commands would timeout. This will not send queue deletion commands to a drive that isn't present and fail after ioremap, significantly speeding up surprise removal; previously this took over 2 minutes per IO queue pair created, but this will complete removing the device within a few seconds. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: Abort timed out commandsKeith Busch2014-01-271-1/+67
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Send nvme abort command to io requests that have timed out on an initialized device. If the command is not returned after another timeout, schedule the controller for reset. Signed-off-by: Keith Busch <keith.busch@intel.com> [fix endianness issues] Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: Schedule reset for failed controllersKeith Busch2014-01-271-2/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Schedules a controller reset when it indicates it has a failed status. If the device does not become ready after a reset, the pci device will be scheduled for removal. Signed-off-by: Keith Busch <keith.busch@intel.com> [fixed checkpatch issue] Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: Device resume error handlingKeith Busch2013-12-161-15/+93
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adds controller error handling on resume power management. If the device fails to initialize, the device is queued for a reset. If the reset fails, a thread is spawned to remove the pci device. If the device resumes as "busy", the device is responding to admin commands but will not create IO queues. In this case, we need to remove the gendisks and free the IO queues since they can't be used and may be holding bios in their lists. From testing, the dma pools require a pci device so this had to change the pci driver 'remove' to release the dma resources in line with that call instead of after all references to the device are released. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: Cache dev->pci_dev in a local pointerMatthew Wilcox2013-12-161-4/+4
| | | | | | | | | | | | | | | | | | Helps with line-length issues Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: Fix lockdep warningsMatthew Wilcox2013-12-161-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | During the initialisation path, the queue lock is taken without interrupt protection. It's perfectly safe to do so, because the interrupt handler can't run at this point, but it confuses lockdep. Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: compat SG_IO ioctlKeith Busch2013-12-162-1/+164
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For 32-bit versions of sg3-utils running on a 64-bit system. This is mostly a copy from the relevent portions of fs/compat_ioctl.c, with slight modifications for going through block_device_operations. Signed-off-by: Keith Busch <keith.busch@intel.com> Reviewed-by: Vishal Verma <vishal.l.verma@linux.intel.com> [fixed up CONFIG_COMPAT=n build problems] Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: remove deprecated IRQF_DISABLEDMichael Opdenacker2013-11-181-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | This patch proposes to remove the use of the IRQF_DISABLED flag It's a NOOP since 2.6.35 and it will be removed one day. Signed-off-by: Michael Opdenacker <michael.opdenacker@free-electrons.com> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: Avoid shift operation when writing cq head doorbellHaiyan Hu2013-11-181-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | Changes the type of dev->db_stride to unsigned and changes the value stored there to be 1 << the current value. Then there is less calculation to be done at completion time. Signed-off-by: Haiyan Hu <huhaiyan@huawei.com> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
* | | Merge tag 'stable/for-linus-3.14-rc0-late-tag' of ↵Linus Torvalds2014-01-311-9/+6
|\ \ \ | | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull Xen bugfixes from Konrad Rzeszutek Wilk: "Bug-fixes for the new features that were added during this cycle. There are also two fixes for long-standing issues for which we have a solution: grant-table operations extra work that was not needed causing performance issues and the self balloon code was too aggressive causing OOMs. Details: - Xen ARM couldn't use the new FIFO events - Xen ARM couldn't use the SWIOTLB if compiled as 32-bit with 64-bit PCIe devices. - Grant table were doing needless M2P operations. - Ratchet down the self-balloon code so it won't OOM. - Fix misplaced kfree in Xen PVH error code paths" * tag 'stable/for-linus-3.14-rc0-late-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/pvh: Fix misplaced kfree from xlated_setup_gnttab_pages drivers: xen: deaggressive selfballoon driver xen/grant-table: Avoid m2p_override during mapping xen/gnttab: Use phys_addr_t to describe the grant frame base address xen: swiotlb: handle sizeof(dma_addr_t) != sizeof(phys_addr_t) arm/xen: Initialize event channels earlier
| * | xen/grant-table: Avoid m2p_override during mappingZoltan Kiss2014-01-311-9/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The grant mapping API does m2p_override unnecessarily: only gntdev needs it, for blkback and future netback patches it just cause a lock contention, as those pages never go to userspace. Therefore this series does the following: - the original functions were renamed to __gnttab_[un]map_refs, with a new parameter m2p_override - based on m2p_override either they follow the original behaviour, or just set the private flag and call set_phys_to_machine - gnttab_[un]map_refs are now a wrapper to call __gnttab_[un]map_refs with m2p_override false - a new function gnttab_[un]map_refs_userspace provides the old behaviour It also removes a stray space from page.h and change ret to 0 if XENFEAT_auto_translated_physmap, as that is the only possible return value there. v2: - move the storing of the old mfn in page->index to gnttab_map_refs - move the function header update to a separate patch v3: - a new approach to retain old behaviour where it needed - squash the patches into one v4: - move out the common bits from m2p* functions, and pass pfn/mfn as parameter - clear page->private before doing anything with the page, so m2p_find_override won't race with this v5: - change return value handling in __gnttab_[un]map_refs - remove a stray space in page.h - add detail why ret = 0 now at some places v6: - don't pass pfn to m2p* functions, just get it locally Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Suggested-by: David Vrabel <david.vrabel@citrix.com> Acked-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | | zram: remove zram->lock in read path and change it with mutexMinchan Kim2014-01-302-12/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Finally, we separated zram->lock dependency from 32bit stat/ table handling so there is no reason to use rw_semaphore between read and write path so this patch removes the lock from read path totally and changes rw_semaphore with mutex. So, we could do old: read-read: OK read-write: NO write-write: NO Now: read-read: OK read-write: OK write-write: NO The below data proves mixed workload performs well 11 times and there is also enhance on write-write path because current rw-semaphore doesn't support SPIN_ON_OWNER. It's side effect but anyway good thing for us. Write-related tests perform better (from 61% to 1058%) but read path has good/bad(from -2.22% to 1.45%) but they are all marginal within stddev. CPU 12 iozone -t -T -l 12 -u 12 -r 16K -s 60M -I +Z -V 0 ==Initial write ==Initial write records: 10 records: 10 avg: 516189.16 avg: 839907.96 std: 22486.53 (4.36%) std: 47902.17 (5.70%) max: 546970.60 max: 909910.35 min: 481131.54 min: 751148.38 ==Rewrite ==Rewrite records: 10 records: 10 avg: 509527.98 avg: 1050156.37 std: 45799.94 (8.99%) std: 40695.44 (3.88%) max: 611574.27 max: 1111929.26 min: 443679.95 min: 980409.62 ==Read ==Read records: 10 records: 10 avg: 4408624.17 avg: 4472546.76 std: 281152.61 (6.38%) std: 163662.78 (3.66%) max: 4867888.66 max: 4727351.03 min: 4058347.69 min: 4126520.88 ==Re-read ==Re-read records: 10 records: 10 avg: 4462147.53 avg: 4363257.75 std: 283546.11 (6.35%) std: 247292.63 (5.67%) max: 4912894.44 max: 4677241.75 min: 4131386.50 min: 4035235.84 ==Reverse Read ==Reverse Read records: 10 records: 10 avg: 4565865.97 avg: 4485818.08 std: 313395.63 (6.86%) std: 248470.10 (5.54%) max: 5232749.16 max: 4789749.94 min: 4185809.62 min: 3963081.34 ==Stride read ==Stride read records: 10 records: 10 avg: 4515981.80 avg: 4418806.01 std: 211192.32 (4.68%) std: 212837.97 (4.82%) max: 4889287.28 max: 4686967.22 min: 4210362.00 min: 4083041.84 ==Random read ==Random read records: 10 records: 10 avg: 4410525.23 avg: 4387093.18 std: 236693.22 (5.37%) std: 235285.23 (5.36%) max: 4713698.47 max: 4669760.62 min: 4057163.62 min: 3952002.16 ==Mixed workload ==Mixed workload records: 10 records: 10 avg: 243234.25 avg: 2818677.27 std: 28505.07 (11.72%) std: 195569.70 (6.94%) max: 288905.23 max: 3126478.11 min: 212473.16 min: 2484150.69 ==Random write ==Random write records: 10 records: 10 avg: 555887.07 avg: 1053057.79 std: 70841.98 (12.74%) std: 35195.36 (3.34%) max: 683188.28 max: 1096125.73 min: 437299.57 min: 992481.93 ==Pwrite ==Pwrite records: 10 records: 10 avg: 501745.93 avg: 810363.09 std: 16373.54 (3.26%) std: 19245.01 (2.37%) max: 518724.52 max: 833359.70 min: 464208.73 min: 765501.87 ==Pread ==Pread records: 10 records: 10 avg: 4539894.60 avg: 4457680.58 std: 197094.66 (4.34%) std: 188965.60 (4.24%) max: 4877170.38 max: 4689905.53 min: 4226326.03 min: 4095739.72 Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | zram: remove workqueue for freeing removed pending slotMinchan Kim2014-01-302-58/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit a0c516cbfc74 ("zram: don't grab mutex in zram_slot_free_noity") introduced free request pending code to avoid scheduling by mutex under spinlock and it was a mess which made code lenghty and increased overhead. Now, we don't need zram->lock any more to free slot so this patch reverts it and then, tb_lock should protect it. Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | zram: introduce zram->tb_lockMinchan Kim2014-01-302-6/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, the zram table is protected by zram->lock but it's rather coarse-grained lock and it makes hard for scalibility. Let's use own rwlock instead of depending on zram->lock. This patch adds new locking so obviously, it would make slow but this patch is just prepartion for removing coarse-grained rw_semaphore(ie, zram->lock) which is hurdle about zram scalability. Final patch in this patchset series will remove the lock from read-path and change rw_semaphore with mutex in write path. With bonus, we could drop pending slot free mess in next patch. Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | zram: use atomic operation for statMinchan Kim2014-01-302-20/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some of fields in zram->stats are protected by zram->lock which is rather coarse-grained so let's use atomic operation without explict locking. This patch is ready for removing dependency of zram->lock in read path which is very coarse-grained rw_semaphore. Of course, this patch adds new atomic operation so it might make slow but my 12CPU test couldn't spot any regression. All gain/lose is marginal within stddev. iozone -t -T -l 12 -u 12 -r 16K -s 60M -I +Z -V 0 ==Initial write ==Initial write records: 50 records: 50 avg: 412875.17 avg: 415638.23 std: 38543.12 (9.34%) std: 36601.11 (8.81%) max: 521262.03 max: 502976.72 min: 343263.13 min: 351389.12 ==Rewrite ==Rewrite records: 50 records: 50 avg: 416640.34 avg: 397914.33 std: 60798.92 (14.59%) std: 46150.42 (11.60%) max: 543057.07 max: 522669.17 min: 304071.67 min: 316588.77 ==Read ==Read records: 50 records: 50 avg: 4147338.63 avg: 4070736.51 std: 179333.25 (4.32%) std: 223499.89 (5.49%) max: 4459295.28 max: 4539514.44 min: 3753057.53 min: 3444686.31 ==Re-read ==Re-read records: 50 records: 50 avg: 4096706.71 avg: 4117218.57 std: 229735.04 (5.61%) std: 171676.25 (4.17%) max: 4430012.09 max: 4459263.94 min: 2987217.80 min: 3666904.28 ==Reverse Read ==Reverse Read records: 50 records: 50 avg: 4062763.83 avg: 4078508.32 std: 186208.46 (4.58%) std: 172684.34 (4.23%) max: 4401358.78 max: 4424757.22 min: 3381625.00 min: 3679359.94 ==Stride read ==Stride read records: 50 records: 50 avg: 4094933.49 avg: 4082170.22 std: 185710.52 (4.54%) std: 196346.68 (4.81%) max: 4478241.25 max: 4460060.97 min: 3732593.23 min: 3584125.78 ==Random read ==Random read records: 50 records: 50 avg: 4031070.04 avg: 4074847.49 std: 192065.51 (4.76%) std: 206911.33 (5.08%) max: 4356931.16 max: 4399442.56 min: 3481619.62 min: 3548372.44 ==Mixed workload ==Mixed workload records: 50 records: 50 avg: 149925.73 avg: 149675.54 std: 7701.26 (5.14%) std: 6902.09 (4.61%) max: 191301.56 max: 175162.05 min: 133566.28 min: 137762.87 ==Random write ==Random write records: 50 records: 50 avg: 404050.11 avg: 393021.47 std: 58887.57 (14.57%) std: 42813.70 (10.89%) max: 601798.09 max: 524533.43 min: 325176.99 min: 313255.34 ==Pwrite ==Pwrite records: 50 records: 50 avg: 411217.70 avg: 411237.96 std: 43114.99 (10.48%) std: 33136.29 (8.06%) max: 530766.79 max: 471899.76 min: 320786.84 min: 317906.94 ==Pread ==Pread records: 50 records: 50 avg: 4154908.65 avg: 4087121.92 std: 151272.08 (3.64%) std: 219505.04 (5.37%) max: 4459478.12 max: 4435857.38 min: 3730512.41 min: 3101101.67 Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | zram: remove unnecessary freeMinchan Kim2014-01-301-8/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit a0c516cbfc74 ("zram: don't grab mutex in zram_slot_free_noity") introduced pending zram slot free in zram's write path in case of missing slot free by memory allocation failure in zram_slot_free_notify but it is not necessary because we have already freed the slot right before overwriting. Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jerome Marchand <jmarchan@redhat.com> Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | zram: delay pending free request in read pathMinchan Kim2014-01-301-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sergey reported we don't need to handle pending free request every I/O so that this patch removes it in read path while we remain it in write path. Let's consider below example. Swap subsystem ask to zram "A" block free by swap_slot_free_notify but zram had been pended it without real freeing. Swap subsystem allocates "A" block for new data but request pended for a long time just handled and zram blindly free new data on the "A" block. :( That's why we couldn't remove handle pending free request right before zram-write. Signed-off-by: Minchan Kim <minchan@kernel.org> Reported-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | zram: fix race between reset and flushing pending workMinchan Kim2014-01-301-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Dan and Sergey reported that there is a racy between reset and flushing of pending work so that it could make oops by freeing zram->meta in reset while zram_slot_free can access zram->meta if new request is adding during the race window. This patch moves flush after taking init_lock so it prevents new request so that it closes the race. Signed-off-by: Minchan Kim <minchan@kernel.org> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jerome Marchand <jmarchan@redhat.com> Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | zram: add copyrightMinchan Kim2014-01-302-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | Add my copyright to the zram source code which I maintain. Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | zram: remove old private project commentMinchan Kim2014-01-303-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove the old private compcache project address so upcoming patches should be sent to LKML because we Linux kernel community will take care. Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | zram: promote zram from stagingMinchan Kim2014-01-306-0/+1149
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Zram has lived in staging for a LONG LONG time and have been fixed/improved by many contributors so code is clean and stable now. Of course, there are lots of product using zram in real practice. The major TV companys have used zram as swap since two years ago and recently our production team released android smart phone with zram which is used as swap, too and recently Android Kitkat start to use zram for small memory smart phone. And there was a report Google released their ChromeOS with zram, too and cyanogenmod have been used zram long time ago. And I heard some disto have used zram block device for tmpfs. In addition, I saw many report from many other peoples. For example, Lubuntu start to use it. The benefit of zram is very clear. With my experience, one of the benefit was to remove jitter of video application with backgroud memory pressure. It would be effect of efficient memory usage by compression but more issue is whether swap is there or not in the system. Recent mobile platforms have used JAVA so there are many anonymous pages. But embedded system normally are reluctant to use eMMC or SDCard as swap because there is wear-leveling and latency issues so if we do not use swap, it means we can't reclaim anoymous pages and at last, we could encounter OOM kill. :( Although we have real storage as swap, it was a problem, too. Because it sometime ends up making system very unresponsible caused by slow swap storage performance. Quote from Luigi on Google "Since Chrome OS was mentioned: the main reason why we don't use swap to a disk (rotating or SSD) is because it doesn't degrade gracefully and leads to a bad interactive experience. Generally we prefer to manage RAM at a higher level, by transparently killing and restarting processes. But we noticed that zram is fast enough to be competitive with the latter, and it lets us make more efficient use of the available RAM. " and he announced. http://www.spinics.net/lists/linux-mm/msg57717.html Other uses case is to use zram for block device. Zram is block device so anyone can format the block device and mount on it so some guys on the internet start zram as /var/tmp. http://forums.gentoo.org/viewtopic-t-838198-start-0.html Let's promote zram and enhance/maintain it instead of removing. Signed-off-by: Minchan Kim <minchan@kernel.org> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Nitin Gupta <ngupta@vflare.org> Acked-by: Pekka Enberg <penberg@kernel.org> Cc: Bob Liu <bob.liu@oracle.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Hugh Dickins <hughd@google.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Luigi Semenzato <semenzato@google.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Seth Jennings <sjenning@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | Merge branch 'for-3.14/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds2014-01-3010-130/+205
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull block IO driver changes from Jens Axboe: - bcache update from Kent Overstreet. - two bcache fixes from Nicholas Swenson. - cciss pci init error fix from Andrew. - underflow fix in the parallel IDE pg_write code from Dan Carpenter. I'm sure the 1 (or 0) users of that are now happy. - two PCI related fixes for sx8 from Jingoo Han. - floppy init fix for first block read from Jiri Kosina. - pktcdvd error return miss fix from Julia Lawall. - removal of IRQF_SHARED from the SEGA Dreamcast CD-ROM code from Michael Opdenacker. - comment typo fix for the loop driver from Olaf Hering. - potential oops fix for null_blk from Raghavendra K T. - two fixes from Sam Bradshaw (Micron) for the mtip32xx driver, fixing an OOM problem and a problem with handling security locked conditions * 'for-3.14/drivers' of git://git.kernel.dk/linux-block: (47 commits) mg_disk: Spelling s/finised/finished/ null_blk: Null pointer deference problem in alloc_page_buffers mtip32xx: Correctly handle security locked condition mtip32xx: Make SGL container per-command to eliminate high order dma allocation drivers/block/loop.c: fix comment typo in loop_config_discard drivers/block/cciss.c:cciss_init_one(): use proper errnos drivers/block/paride/pg.c: underflow bug in pg_write() drivers/block/sx8.c: remove unnecessary pci_set_drvdata() drivers/block/sx8.c: use module_pci_driver() floppy: bail out in open() if drive is not responding to block0 read bcache: Fix auxiliary search trees for key size > cacheline size bcache: Don't return -EINTR when insert finished bcache: Improve bucket_prio() calculation bcache: Add bch_bkey_equal_header() bcache: update bch_bkey_try_merge bcache: Move insert_fixup() to btree_keys_ops bcache: Convert sorting to btree_keys bcache: Convert debug code to btree_keys bcache: Convert btree_iter to struct btree_keys bcache: Refactor bset_tree sysfs stats ...
| * | | mg_disk: Spelling s/finised/finished/Geert Uytterhoeven2014-01-211-1/+1
| | | | | | | | | | | | | | | | | | | | Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | null_blk: Null pointer deference problem in alloc_page_buffersRaghavendra K T2014-01-211-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we load the null_blk module with bs=8k we get following oops: [ 3819.812190] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008 [ 3819.812387] IP: [<ffffffff81170aa5>] create_empty_buffers+0x28/0xaf [ 3819.812527] PGD 219244067 PUD 215a06067 PMD 0 [ 3819.812640] Oops: 0000 [#1] SMP [ 3819.812772] Modules linked in: null_blk(+) Fix that by resetting block size to PAGE_SIZE if it is greater than PAGE_SIZE Reported-by: Sumanth <sumantk2@linux.vnet.ibm.com> Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Reviewed-by: Matias Bjorling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | mtip32xx: Correctly handle security locked conditionSam Bradshaw2014-01-212-3/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If power is removed during a secure erase, the drive will end up in a security locked condition. This patch causes the driver to identify, log, and flag the security lock state. IOs are prevented from submission to the drive until the locked state is addressed with a secure erase. Bumped version number to reflect this capability. Signed-off-by: Sam Bradshaw <sbradshaw@micron.com> Signed-off-by: Asai Thambi S P <asamymuthupa@micron.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | mtip32xx: Make SGL container per-command to eliminate high order dma allocationSam Bradshaw2014-01-212-97/+149
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The mtip32xx driver makes a high order dma memory allocation to store a command index table, some dedicated buffers, and a command header & SGL blob. This allocation can fail with a surprise insert under low & fragmented memory conditions. This patch breaks these regions up into separate low order allocations and increases the maximum number of segments a single command SGL can have. We wanted to allow at least 256 segments for 1 MB direct IO. Since the command header occupies the first 0x80 bytes of the SGL blob, that meant we needed two 4k pages to contain the header and SGL. The two pages allow up to 504 SGL segments. Signed-off-by: Sam Bradshaw <sbradshaw@micron.com> Signed-off-by: Asai Thambi S P <asamymuthupa@micron.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | Merge branch 'for-jens' of ↵Jens Axboe2014-01-211-9/+27
| |\ \ \ | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/linux-block into for-3.14/drivers
| | * | | floppy: bail out in open() if drive is not responding to block0 readJiri Kosina2014-01-171-9/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In case reading of block 0 during open() fails, it is not the right thing to let open() succeed. Fix this by introducing FD_OPEN_SHOULD_FAIL_BIT flag, and setting it in case the bio callback encounters an error while trying to read block 0. As a bonus, this works around certain broken userspace (blkid), which is not able to properly handle read()s returning IO errors. Hence be nice to those, and bail out during open() already; if block 0 is not readable, read()s are not going to provide any meaningful data anyway. Signed-off-by: Jiri Kosina <jkosina@suse.cz>
| * | | | drivers/block/loop.c: fix comment typo in loop_config_discardOlaf Hering2014-01-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Discard requests are ignored if the encryption is enabled for the given loop device. Update comment to match the code, and similar comments elsewhere in the file. Signed-off-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | | drivers/block/cciss.c:cciss_init_one(): use proper errnosAndrew Morton2014-01-211-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | pci_driver.probe should return a meaningful errno, not -1. Cc: Jens Axboe <axboe@kernel.dk> Cc: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | | drivers/block/paride/pg.c: underflow bug in pg_write()Dan Carpenter2014-01-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The test here can underflow so we pass bogus lengths to the hardware. It's a static checker fix and I don't know the impact. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | | drivers/block/sx8.c: remove unnecessary pci_set_drvdata()Jingoo Han2014-01-211-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The driver core clears the driver data to NULL after device_release or on probe failure. Thus, it is not needed to manually clear the device driver data to NULL. Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | | drivers/block/sx8.c: use module_pci_driver()Jingoo Han2014-01-211-14/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use module_pci_driver() macro which makes the code smaller and simpler. Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | | Merge branch 'for-3.14/core' into for-3.14/driversJens Axboe2014-01-083-33/+88
| |\ \ \ \ | | |/ / / | |/| | | | | | | | We need the updated code to make bcache easier to merge.
| * | | | pktcdvd: fix error return codeJulia Lawall2014-01-031-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Set the return variable to an error code as done elsewhere in the function. A simplified version of the semantic match that finds this problem is as follows: (http://coccinelle.lip6.fr/) // <smpl> ( if@p1 (\(ret < 0\|ret != 0\)) { ... return ret; } | ret@p1 = 0 ) ... when != ret = e1 when != &ret *if(...) { ... when != ret = e2 when forall return ret; } // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* | | | | Merge branch 'for-3.14/core' of git://git.kernel.dk/linux-blockLinus Torvalds2014-01-3024-502/+342
|\ \ \ \ \ | | |/ / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull core block IO changes from Jens Axboe: "The major piece in here is the immutable bio_ve series from Kent, the rest is fairly minor. It was supposed to go in last round, but various issues pushed it to this release instead. The pull request contains: - Various smaller blk-mq fixes from different folks. Nothing major here, just minor fixes and cleanups. - Fix for a memory leak in the error path in the block ioctl code from Christian Engelmayer. - Header export fix from CaiZhiyong. - Finally the immutable biovec changes from Kent Overstreet. This enables some nice future work on making arbitrarily sized bios possible, and splitting more efficient. Related fixes to immutable bio_vecs: - dm-cache immutable fixup from Mike Snitzer. - btrfs immutable fixup from Muthu Kumar. - bio-integrity fix from Nic Bellinger, which is also going to stable" * 'for-3.14/core' of git://git.kernel.dk/linux-block: (44 commits) xtensa: fixup simdisk driver to work with immutable bio_vecs block/blk-mq-cpu.c: use hotcpu_notifier() blk-mq: for_each_* macro correctness block: Fix memory leak in rw_copy_check_uvector() handling bio-integrity: Fix bio_integrity_verify segment start bug block: remove unrelated header files and export symbol blk-mq: uses page->list incorrectly blk-mq: use __smp_call_function_single directly btrfs: fix missing increment of bi_remaining Revert "block: Warn and free bio if bi_end_io is not set" block: Warn and free bio if bi_end_io is not set blk-mq: fix initializing request's start time block: blk-mq: don't export blk_mq_free_queue() block: blk-mq: make blk_sync_queue support mq block: blk-mq: support draining mq queue dm cache: increment bi_remaining when bi_end_io is restored block: fixup for generic bio chaining block: Really silence spurious compiler warnings block: Silence spurious compiler warnings block: Kill bio_pair_split() ...
| * | | | Merge tag 'v3.13-rc6' into for-3.14/coreJens Axboe2013-12-313-33/+88
| |\ \ \ \ | | |/ / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Needed to bring blk-mq uptodate, since changes have been going in since for-3.14/core was established. Fixup merge issues related to the immutable biovec changes. Signed-off-by: Jens Axboe <axboe@kernel.dk> Conflicts: block/blk-flush.c fs/btrfs/check-integrity.c fs/btrfs/extent_io.c fs/btrfs/scrub.c fs/logfs/dev_bdev.c
| * | | | block: Introduce new bio_split()Kent Overstreet2013-11-232-159/+83
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The new bio_split() can split arbitrary bios - it's not restricted to single page bios, like the old bio_split() (previously renamed to bio_pair_split()). It also has different semantics - it doesn't allocate a struct bio_pair, leaving it up to the caller to handle completions. Then convert the existing bio_pair_split() users to the new bio_split() - and also nvme, which was open coding bio splitting. (We have to take that BUG_ON() out of bio_integrity_trim() because this bio_split() needs to use it, and there's no reason it has to be used on bios marked as cloned; BIO_CLONED doesn't seem to have clearly documented semantics anyways.) Signed-off-by: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Martin K. Petersen <martin.petersen@oracle.com> Cc: Matthew Wilcox <matthew.r.wilcox@intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Neil Brown <neilb@suse.de>
| * | | | block: Rename bio_split() -> bio_pair_split()Kent Overstreet2013-11-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is prep work for introducing a more general bio_split(). Signed-off-by: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: NeilBrown <neilb@suse.de> Cc: Alasdair Kergon <agk@redhat.com> Cc: Lars Ellenberg <lars.ellenberg@linbit.com> Cc: Peter Osterlund <petero2@telia.com> Cc: Sage Weil <sage@inktank.com>
| * | | | rbd: Refactor bio cloningKent Overstreet2013-11-231-62/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that we've got drivers converted to the new immutable bvec primitives, bio splitting becomes much easier - this is how the new bio_split() will work. (Someone more familiar with the ceph code could probably use bio_clone_fast() instead of bio_clone() here). Signed-off-by: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Yehuda Sadeh <yehuda@inktank.com> Cc: Alex Elder <elder@inktank.com> Cc: ceph-devel@vger.kernel.org
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