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* Merge tag 'pci-v3.16-changes' of ↵Linus Torvalds2014-06-02
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci into next Pull PCI changes from Bjorn Helgaas: "Enumeration - Notify driver before and after device reset (Keith Busch) - Use reset notification in NVMe (Keith Busch) NUMA - Warn if we have to guess host bridge node information (Myron Stowe) - Work around AMD Fam15h BIOSes that fail to provide _PXM (Suravee Suthikulpanit) - Clean up and mark early_root_info_init() as deprecated (Suravee Suthikulpanit) Driver binding - Add "driver_override" for force specific binding (Alex Williamson) - Fail "new_id" addition for devices we already know about (Bandan Das) Resource management - Support BAR sizes up to 8GB (Nikhil Rao, Alan Cox) - Don't move IORESOURCE_PCI_FIXED resources (Bjorn Helgaas) - Mark SBx00 HPET BAR as IORESOURCE_PCI_FIXED (Bjorn Helgaas) - Fail safely if we can't handle BARs larger than 4GB (Bjorn Helgaas) - Reject BAR above 4GB if dma_addr_t is too small (Bjorn Helgaas) - Don't convert BAR address to resource if dma_addr_t is too small (Bjorn Helgaas) - Don't set BAR to zero if dma_addr_t is too small (Bjorn Helgaas) - Don't print anything while decoding is disabled (Bjorn Helgaas) - Don't add disabled subtractive decode bus resources (Bjorn Helgaas) - Add resource allocation comments (Bjorn Helgaas) - Restrict 64-bit prefetchable bridge windows to 64-bit resources (Yinghai Lu) - Assign i82875p_edac PCI resources before adding device (Yinghai Lu) PCI device hotplug - Remove unnecessary "dev->bus" test (Bjorn Helgaas) - Use PCI_EXP_SLTCAP_PSN define (Bjorn Helgaas) - Fix rphahp endianess issues (Laurent Dufour) - Acknowledge spurious "cmd completed" event (Rajat Jain) - Allow hotplug service drivers to operate in polling mode (Rajat Jain) - Fix cpqphp possible NULL dereference (Rickard Strandqvist) MSI - Replace pci_enable_msi_block() by pci_enable_msi_exact() (Alexander Gordeev) - Replace pci_enable_msix() by pci_enable_msix_exact() (Alexander Gordeev) - Simplify populate_msi_sysfs() (Jan Beulich) Virtualization - Add Intel Patsburg (X79) root port ACS quirk (Alex Williamson) - Mark RTL8110SC INTx masking as broken (Alex Williamson) Generic host bridge driver - Add generic PCI host controller driver (Will Deacon) Freescale i.MX6 - Use new clock names (Lucas Stach) - Drop old IRQ mapping (Lucas Stach) - Remove optional (and unused) IRQs (Lucas Stach) - Add support for MSI (Lucas Stach) - Fix imx6_add_pcie_port() section mismatch warning (Sachin Kamat) Renesas R-Car - Add gen2 device tree support (Ben Dooks) - Use new OF interrupt mapping when possible (Lucas Stach) - Add PCIe driver (Phil Edworthy) - Add PCIe MSI support (Phil Edworthy) - Add PCIe device tree bindings (Phil Edworthy) Samsung Exynos - Remove unnecessary OOM messages (Jingoo Han) - Fix add_pcie_port() section mismatch warning (Sachin Kamat) Synopsys DesignWare - Make MSI ISR shared IRQ aware (Lucas Stach) Miscellaneous - Check for broken config space aliasing (Alex Williamson) - Update email address (Ben Hutchings) - Fix Broadcom CNB20LE unintended sign extension (Bjorn Helgaas) - Fix incorrect vgaarb conditional in WARN_ON() (Bjorn Helgaas) - Remove unnecessary __ref annotations (Bjorn Helgaas) - Add arch/x86/kernel/quirks.c to MAINTAINERS PCI file patterns (Bjorn Helgaas) - Fix use of uninitialized MPS value (Bjorn Helgaas) - Tidy x86/gart messages (Bjorn Helgaas) - Fix return value from pci_user_{read,write}_config_*() (Gavin Shan) - Turn pcibios_penalize_isa_irq() into a weak function (Hanjun Guo) - Remove unused serial device IDs (Jean Delvare) - Use designated initialization in PCI_VDEVICE (Mark Rustad) - Fix powerpc NULL dereference in pci_root_buses traversal (Mike Qiu) - Configure MPS on ARM (Murali Karicheri) - Remove unnecessary includes of <linux/init.h> (Paul Gortmaker) - Move Open Firmware devspec attribute to PCI common code (Sebastian Ott) - Use pdev->dev.groups for attribute creation on s390 (Sebastian Ott) - Remove pcibios_add_platform_entries() (Sebastian Ott) - Add new ID for Intel GPU "spurious interrupt" quirk (Thomas Jarosch) - Rename pci_is_bridge() to pci_has_subordinate() (Yijing Wang) - Add and use new pci_is_bridge() interface (Yijing Wang) - Make pci_bus_add_device() void (Yijing Wang) DMA API - Clarify physical/bus address distinction in docs (Bjorn Helgaas) - Fix typos in docs (Emilio López) - Update dma_pool_create ()and dma_pool_alloc() descriptions (Gioh Kim) - Change dma_declare_coherent_memory() CPU address to phys_addr_t (Bjorn Helgaas) - Pass GAPSPCI_DMA_BASE CPU & bus address to dma_declare_coherent_memory() (Bjorn Helgaas)" * tag 'pci-v3.16-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (92 commits) MAINTAINERS: Add generic PCI host controller driver PCI: generic: Add generic PCI host controller driver PCI: imx6: Add support for MSI PCI: designware: Make MSI ISR shared IRQ aware PCI: imx6: Remove optional (and unused) IRQs PCI: imx6: Drop old IRQ mapping PCI: imx6: Use new clock names i82875p_edac: Assign PCI resources before adding device ARM/PCI: Call pcie_bus_configure_settings() to set MPS PCI: imx6: Fix imx6_add_pcie_port() section mismatch warning PCI: Make pci_bus_add_device() void PCI: exynos: Fix add_pcie_port() section mismatch warning PCI: Introduce new device binding path using pci_dev.driver_override PCI: rcar: Add gen2 device tree support PCI: cpqphp: Fix possible null pointer dereference PCI: rcar: Add R-Car PCIe device tree bindings PCI: rcar: Add MSI support for PCIe PCI: rcar: Add Renesas R-Car PCIe driver PCI: Fix return value from pci_user_{read,write}_config_*() PCI: exynos: Remove unnecessary OOM messages ...
| * NVMe: Implement PCIe reset notification callbackKeith Busch2014-05-27
| | | | | | | | | | | | | | Quiesce and shutdown the device prior to reset, then restart the device and resume IO after. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
* | Merge branch 'for-3.16/core' of git://git.kernel.dk/linux-block into nextLinus Torvalds2014-06-02
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull block core updates from Jens Axboe: "It's a big(ish) round this time, lots of development effort has gone into blk-mq in the last 3 months. Generally we're heading to where 3.16 will be a feature complete and performant blk-mq. scsi-mq is progressing nicely and will hopefully be in 3.17. A nvme port is in progress, and the Micron pci-e flash driver, mtip32xx, is converted and will be sent in with the driver pull request for 3.16. This pull request contains: - Lots of prep and support patches for scsi-mq have been integrated. All from Christoph. - API and code cleanups for blk-mq from Christoph. - Lots of good corner case and error handling cleanup fixes for blk-mq from Ming Lei. - A flew of blk-mq updates from me: * Provide strict mappings so that the driver can rely on the CPU to queue mapping. This enables optimizations in the driver. * Provided a bitmap tagging instead of percpu_ida, which never really worked well for blk-mq. percpu_ida relies on the fact that we have a lot more tags available than we really need, it fails miserably for cases where we exhaust (or are close to exhausting) the tag space. * Provide sane support for shared tag maps, as utilized by scsi-mq * Various fixes for IO timeouts. * API cleanups, and lots of perf tweaks and optimizations. - Remove 'buffer' from struct request. This is ancient code, from when requests were always virtually mapped. Kill it, to reclaim some space in struct request. From me. - Remove 'magic' from blk_plug. Since we store these on the stack and since we've never caught any actual bugs with this, lets just get rid of it. From me. - Only call part_in_flight() once for IO completion, as includes two atomic reads. Hopefully we'll get a better implementation soon, as the part IO stats are now one of the more expensive parts of doing IO on blk-mq. From me. - File migration of block code from {mm,fs}/ to block/. This includes bio.c, bio-integrity.c, bounce.c, and ioprio.c. From me, from a discussion on lkml. That should describe the meat of the pull request. Also has various little fixes and cleanups from Dave Jones, Shaohua Li, Duan Jiong, Fengguang Wu, Fabian Frederick, Randy Dunlap, Robert Elliott, and Sam Bradshaw" * 'for-3.16/core' of git://git.kernel.dk/linux-block: (100 commits) blk-mq: push IPI or local end_io decision to __blk_mq_complete_request() blk-mq: remember to start timeout handler for direct queue block: ensure that the timer is always added blk-mq: blk_mq_unregister_hctx() can be static blk-mq: make the sysfs mq/ layout reflect current mappings blk-mq: blk_mq_tag_to_rq should handle flush request block: remove dead code in scsi_ioctl:blk_verify_command blk-mq: request initialization optimizations block: add queue flag for disabling SG merging block: remove 'magic' from struct blk_plug blk-mq: remove alloc_hctx and free_hctx methods blk-mq: add file comments and update copyright notices blk-mq: remove blk_mq_alloc_request_pinned blk-mq: do not use blk_mq_alloc_request_pinned in blk_mq_map_request blk-mq: remove blk_mq_wait_for_tags blk-mq: initialize request in __blk_mq_alloc_request blk-mq: merge blk_mq_alloc_reserved_request into blk_mq_alloc_request blk-mq: add helper to insert requests from irq context blk-mq: remove stale comment for blk_mq_complete_request() blk-mq: allow non-softirq completions ...
| * | blk-mq: remove alloc_hctx and free_hctx methodsChristoph Hellwig2014-05-28
| | | | | | | | | | | | | | | | | | | | | | | | There is no need for drivers to control hardware context allocation now that we do the context to node mapping in common code. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
| * | blk-mq: pass in suggested NUMA node to ->alloc_hctx()Jens Axboe2014-05-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Drivers currently have to figure this out on their own, and they are missing information to do it properly. The ones that did attempt to do it, do it wrong. So just pass in the suggested node directly to the alloc function. Signed-off-by: Jens Axboe <axboe@fb.com>
| * | sd/skd: stuff discard page in request->completion_dataJens Axboe2014-04-16
| | | | | | | | | | | | | | | | | | | | | | | | Store the pointer to the page there, so we can always safely reference it from end_io context where ->bio may have been cleared. Signed-off-by: Jens Axboe <axboe@fb.com>
| * | blk-mq: add async parameter to blk_mq_start_stopped_hw_queuesChristoph Hellwig2014-04-16
| | | | | | | | | | | | | | | Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
| * | blk-mq: split out tag initialization, support shared tagsChristoph Hellwig2014-04-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a new blk_mq_tag_set structure that gets set up before we initialize the queue. A single blk_mq_tag_set structure can be shared by multiple queues. Signed-off-by: Christoph Hellwig <hch@lst.de> Modular export of blk_mq_{alloc,free}_tagset added by me. Signed-off-by: Jens Axboe <axboe@fb.com>
| * | blk-mq: add ->init_request and ->exit_request methodsChristoph Hellwig2014-04-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current blk_mq_init_commands/blk_mq_free_commands interface has a two problems: 1) Because only the constructor is passed to blk_mq_init_commands there is no easy way to clean up when a comman initialization failed. The current code simply leaks the allocations done in the constructor. 2) There is no good place to call blk_mq_free_commands: before blk_cleanup_queue there is no guarantee that all outstanding commands have completed, so we can't free them yet. After blk_cleanup_queue the queue has usually been freed. This can be worked around by grabbing an unconditional reference before calling blk_cleanup_queue and dropping it after blk_mq_free_commands is done, although that's not exatly pretty and driver writers are guaranteed to get it wrong sooner or later. Both issues are easily fixed by making the request constructor and destructor normal blk_mq_ops methods. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
| * | blk-mq: do not initialize req->specialChristoph Hellwig2014-04-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Drivers can reach their private data easily using the blk_mq_rq_to_pdu helper and don't need req->special. By not initializing it code can be simplified nicely, and we also shave off a few more instructions from the I/O path. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
| * | block: remove struct request buffer memberJens Axboe2014-04-15
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | This was used in the olden days, back when onions were proper yellow. Basically it mapped to the current buffer to be transferred. With highmem being added more than a decade ago, most drivers map pages out of a bio, and rq->buffer isn't pointing at anything valid. Convert old style drivers to just use bio_data(). For the discard payload use case, just reference the page in the bio. Signed-off-by: Jens Axboe <axboe@fb.com>
* | Merge branch 'for-linus' of ↵Linus Torvalds2014-06-02
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k into next Pull m68k updates from Geert Uytterhoeven: "Highlights: - support for running kernels in fast TT-RAM instead of slow ST-RAM on Atari - multi-platform EARLY_PRINTK - better support for machines with lots of RAM (think ARAnyM), and for running kernels larger than 4 MiB (think multi-platform)" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k: m68k/hp300: Convert printk to pr_foo() m68k/apollo: Convert printk to pr_foo() m68k/amiga: Convert printk(foo to pr_foo() m68k: Increase initial mapping to 8 or 16 MiB if possible m68k: Update defconfigs for v3.15-rc2 m68k/atari: fix SCC initialization for debug console m68k/mvme16x: Adopt common boot console m68k: Multi-platform EARLY_PRINTK m68k: Toward platform agnostic framebuffer debug logging m68k/atari - atari_scsi: use correct virt/phys translation for DMA buffer m68k/atari - ataflop: use correct virt/phys translation for DMA buffer m68k/atari - atafb: convert allocation of fb ram to new interface m68k/atari - stram: alloc ST-RAM pool even if kernel not in ST-RAM
| * | m68k/atari - ataflop: use correct virt/phys translation for DMA bufferMichael Schmitz2014-05-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With the kernel running from FastRAM instead of ST-RAM, none of ST-RAM is mapped by mem_init, and DMA-addressable buffer must be mapped by ioremap. Use platform specific virt/phys translation helpers for this case. Signed-off-by: Michael Schmitz <schmitz@debian.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
* | | virtio_blk: fix race between start and stop queueMing Lei2014-05-27
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When there isn't enough vring descriptor for adding to vq, blk-mq will be put as stopped state until some of pending descriptors are completed & freed. Unfortunately, the vq's interrupt may come just before blk-mq's BLK_MQ_S_STOPPED flag is set, so the blk-mq will still be kept as stopped even though lots of descriptors are completed and freed in the interrupt handler. The worst case is that all pending descriptors are freed in the interrupt handler, and the queue is kept as stopped forever. This patch fixes the problem by starting/stopping blk-mq with holding vq_lock. Cc: Jens Axboe <axboe@kernel.dk> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Ming Lei <tom.leiming@gmail.com> Cc: stable@kernel.org Signed-off-by: Jens Axboe <axboe@fb.com> Conflicts: drivers/block/virtio_blk.c
* | floppy: don't write kernel-only members to FDRAWCMD ioctl outputMatthew Daley2014-05-05
| | | | | | | | | | | | | | | | | | Do not leak kernel-only floppy_raw_cmd structure members to userspace. This includes the linked-list pointer and the pointer to the allocated DMA space. Signed-off-by: Matthew Daley <mattd@bugfuzz.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | floppy: ignore kernel-only members in FDRAWCMD ioctl inputMatthew Daley2014-05-05
|/ | | | | | | | | Always clear out these floppy_raw_cmd struct members after copying the entire structure from userspace so that the in-kernel version is always valid and never left in an interdeterminate state. Signed-off-by: Matthew Daley <mattd@bugfuzz.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for-linus' of ↵Linus Torvalds2014-04-12
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs updates from Al Viro: "The first vfs pile, with deep apologies for being very late in this window. Assorted cleanups and fixes, plus a large preparatory part of iov_iter work. There's a lot more of that, but it'll probably go into the next merge window - it *does* shape up nicely, removes a lot of boilerplate, gets rid of locking inconsistencie between aio_write and splice_write and I hope to get Kent's direct-io rewrite merged into the same queue, but some of the stuff after this point is having (mostly trivial) conflicts with the things already merged into mainline and with some I want more testing. This one passes LTP and xfstests without regressions, in addition to usual beating. BTW, readahead02 in ltp syscalls testsuite has started giving failures since "mm/readahead.c: fix readahead failure for memoryless NUMA nodes and limit readahead pages" - might be a false positive, might be a real regression..." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits) missing bits of "splice: fix racy pipe->buffers uses" cifs: fix the race in cifs_writev() ceph_sync_{,direct_}write: fix an oops on ceph_osdc_new_request() failure kill generic_file_buffered_write() ocfs2_file_aio_write(): switch to generic_perform_write() ceph_aio_write(): switch to generic_perform_write() xfs_file_buffered_aio_write(): switch to generic_perform_write() export generic_perform_write(), start getting rid of generic_file_buffer_write() generic_file_direct_write(): get rid of ppos argument btrfs_file_aio_write(): get rid of ppos kill the 5th argument of generic_file_buffered_write() kill the 4th argument of __generic_file_aio_write() lustre: don't open-code kernel_recvmsg() ocfs2: don't open-code kernel_recvmsg() drbd: don't open-code kernel_recvmsg() constify blk_rq_map_user_iov() and friends lustre: switch to kernel_sendmsg() ocfs2: don't open-code kernel_sendmsg() take iov_iter stuff to mm/iov_iter.c process_vm_access: tidy up a bit ...
| * drbd: don't open-code kernel_recvmsg()Al Viro2014-04-01
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * switch nbd to sockfd_lookup/sockfd_putAl Viro2014-04-01
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | Merge git://git.infradead.org/users/willy/linux-nvmeLinus Torvalds2014-04-11
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull NVMe driver updates from Matthew Wilcox: "Various updates to the NVMe driver. The most user-visible change is that drive hotplugging now works and CPU hotplug while an NVMe drive is installed should also work better" * git://git.infradead.org/users/willy/linux-nvme: NVMe: Retry failed commands with non-fatal errors NVMe: Add getgeo to block ops NVMe: Start-stop nvme_thread during device add-remove. NVMe: Make I/O timeout a module parameter NVMe: CPU hot plug notification NVMe: per-cpu io queues NVMe: Replace DEFINE_PCI_DEVICE_TABLE NVMe: Fix divide-by-zero in nvme_trans_io_get_num_cmds NVMe: IOCTL path RCU protect queue access NVMe: RCU protected access to io queues NVMe: Initialize device reference count earlier NVMe: Add CONFIG_PM_SLEEP to suspend/resume functions
| * | NVMe: Retry failed commands with non-fatal errorsKeith Busch2014-04-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For commands returned with failed status, queue these for resubmission and continue retrying them until success or for a limited amount of time. The final timeout was arbitrarily chosen so requests can't be retried indefinitely. Since these are requeued on the nvmeq that submitted the command, the callbacks have to take an nvmeq instead of an nvme_dev as a parameter so that we can use the locked queue to append the iod to retry later. The nvme_iod conviently can be used to track how long we've been trying to successfully complete an iod request. The nvme_iod also provides the nvme prp dma mappings, so I had to move a few things around so we can keep those mappings. Signed-off-by: Keith Busch <keith.busch@intel.com> [fixed checkpatch issue with long line] Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: Add getgeo to block opsKeith Busch2014-04-10
| | | | | | | | | | | | | | | | | | | | | | | | Some programs require HDIO_GETGEO work, which requires we implement getgeo. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: Start-stop nvme_thread during device add-remove.Dan McLeran2014-04-10
| | | | | | | | | | | | | | | | | | | | | | | | Done to ensure nvme_thread is not running when there are no devices to poll. Signed-off-by: Dan McLeran <daniel.mcleran@intel.com> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: Make I/O timeout a module parameterKeith Busch2014-04-10
| | | | | | | | | | | | | | | | | | | | | | | | Increase the default timeout to 30 seconds to match SCSI. Signed-off-by: Keith Busch <keith.busch@intel.com> [use byte instead of ushort] Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: CPU hot plug notificationKeith Busch2014-04-10
| | | | | | | | | | | | | | | | | | | | | | | | Registers with hot cpu notification to rebalance, and potentially allocate additional, io queues. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: per-cpu io queuesKeith Busch2014-04-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The device's IO queues are associated with CPUs, so we can use a per-cpu variable to map the a qid to a cpu. This provides a convienient way to optimally assign queues to multiple cpus when the device supports fewer queues than the host has cpus. The previous implementation may have assigned these poorly in these situations. This patch addresses this by sharing queues among cpus that are "close" together and should have a lower lock contention penalty. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: Replace DEFINE_PCI_DEVICE_TABLEMatthew Wilcox2014-03-24
| | | | | | | | | | | | | | | | | | | | | | | | Checkpatch has started warning against using DEFINE_PCI_DEVICE_TABLE, so replace it. Also update the copyright date and bump the module version number to 0.9. Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: Fix divide-by-zero in nvme_trans_io_get_num_cmdsKeith Busch2014-03-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | dev->max_hw_sectors may be zero to indicate the device has no limit on the number of sectors. nvme_trans_do_nvme_io() should use the software limit, since this is guaranteed to be non-zero. Reported-by: Mundu <mundu2510@gmail.com> Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: IOCTL path RCU protect queue accessKeith Busch2014-03-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds rcu protected access to a queue in the nvme IOCTL path to fix potential races between a surprise removal and queue usage in nvme_submit_sync_cmd. The fix holds the rcu_read_lock() here to prevent the nvme_queue from freeing while this path is executing so it can't sleep, and so this path will no longer wait for a available command id should they all be in use at the time a passthrough IOCTL request is received. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: RCU protected access to io queuesKeith Busch2014-03-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds rcu protected access to nvme_queue to fix a race between a surprise removal freeing the queue and a thread with open reference on a NVMe block device using that queue. The queues do not need to be rcu protected during the initialization or shutdown parts, so I've added a helper function for raw deferencing to get around the sparse errors. There is still a hole in the IOCTL path for the same problem, which is fixed in a subsequent patch. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: Initialize device reference count earlierKeith Busch2014-03-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If an NVMe device becomes ready but fails to create IO queues, the driver creates a character device handle so the device can be managed. The device reference count needs to be initialized before creating the character device. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
| * | NVMe: Add CONFIG_PM_SLEEP to suspend/resume functionsJingoo Han2014-03-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add CONFIG_PM_SLEEP to suspend/resume functions to fix the following build warning when CONFIG_PM_SLEEP is not selected. This is because sleep PM callbacks defined by SIMPLE_DEV_PM_OPS are only used when the CONFIG_PM_SLEEP is enabled. drivers/block/nvme-core.c:2541:12: warning: 'nvme_suspend' defined but not used [-Wunused-function] drivers/block/nvme-core.c:2550:12: warning: 'nvme_resume' defined but not used [-Wunused-function] Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
* | | Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds2014-04-10
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull block layer fixes from Jens Axboe: "A small collection of fixes that should go in before -rc1. The pull request contains: - A two patch fix for a regression with block enabled tagging caused by a commit in the initial pull request. One patch is from Martin and ensures that SCSI doesn't truncate 64-bit block flags, the other one is from me and prevents us from double using struct request queuelist for both completion and busy tags. This caused anything from a boot crash for some, to crashes under load. - A blk-mq fix for a potential soft stall when hot unplugging CPUs with busy IO. - percpu_counter fix is listed in here, that caused a suspend issue with virtio-blk due to percpu counters having an inconsistent state during CPU removal. Andrew sent this in separately a few days ago, but it's here. JFYI. - A few fixes for block integrity from Martin. - A ratelimit fix for loop from Mike Galbraith, to avoid spewing too much in error cases" * 'for-linus' of git://git.kernel.dk/linux-block: block: fix regression with block enabled tagging scsi: Make sure cmd_flags are 64-bit block: Ensure we only enable integrity metadata for reads and writes block: Fix integrity verification block: Fix for_each_bvec() drivers/block/loop.c: ratelimit error messages blk-mq: fix potential stall during CPU unplug with IO pending percpu_counter: fix bad counter state during suspend
| * | | drivers/block/loop.c: ratelimit error messagesMike Galbraith2014-04-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Metric tons of high speed spew is not helpful when things go pear shaped. systemd lost its mind, forgot how to stop services it insists on being sole manager of, massive printk() flood ensued, box eventually died. [16206.684000] loop: Write error at byte offset 11412291584, length 4096. [16206.684000] systemd-journald[1758]: /dev/kmsg buffer overrun, some messages lost. [16206.684000] loop: Write error at byte offset 13155434496, length 4096. [16206.684000] loop: Write error at byte offset 13155438592, length 4096. [16206.684000] loop: Write error at byte offset 13155442688, length 4096. [16206.684000] loop: Write error at byte offset 13960736768, length 4096. [16206.684000] loop: Write error at byte offset 14229172224, length 4096. [16206.684000] systemd-journald[1758]: /dev/kmsg buffer overrun, some messages lost. [16206.684000] loop: Write error at byte offset 14766043136, length 4096. [16206.684000] loop: Write error at byte offset 15034478592, length 4096. [16206.684000] systemd-journald[1758]: /dev/kmsg buffer overrun, some messages lost. Signed-off-by: Mike Galbraith <bitbucket@online.de> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@fb.com>
* | | | Merge branch 'akpm' (incoming from Andrew)Linus Torvalds2014-04-07
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge second patch-bomb from Andrew Morton: - the rest of MM - zram updates - zswap updates - exit - procfs - exec - wait - crash dump - lib/idr - rapidio - adfs, affs, bfs, ufs - cris - Kconfig things - initramfs - small amount of IPC material - percpu enhancements - early ioremap support - various other misc things * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (156 commits) MAINTAINERS: update Intel C600 SAS driver maintainers fs/ufs: remove unused ufs_super_block_third pointer fs/ufs: remove unused ufs_super_block_second pointer fs/ufs: remove unused ufs_super_block_first pointer fs/ufs/super.c: add __init to init_inodecache() doc/kernel-parameters.txt: add early_ioremap_debug arm64: add early_ioremap support arm64: initialize pgprot info earlier in boot x86: use generic early_ioremap mm: create generic early_ioremap() support x86/mm: sparse warning fix for early_memremap lglock: map to spinlock when !CONFIG_SMP percpu: add preemption checks to __this_cpu ops vmstat: use raw_cpu_ops to avoid false positives on preemption checks slub: use raw_cpu_inc for incrementing statistics net: replace __this_cpu_inc in route.c with raw_cpu_inc modules: use raw_cpu_write for initialization of per cpu refcount. mm: use raw_cpu ops for determining current NUMA node percpu: add raw_cpu_ops slub: fix leak of 'name' in sysfs_slab_add ...
| * | | | zram: support REQ_DISCARDJoonsoo Kim2014-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | zram is ram based block device and can be used by backend of filesystem. When filesystem deletes a file, it normally doesn't do anything on data block of that file. It just marks on metadata of that file. This behavior has no problem on disk based block device, but has problems on ram based block device, since we can't free memory used for data block. To overcome this disadvantage, there is REQ_DISCARD functionality. If block device support REQ_DISCARD and filesystem is mounted with discard option, filesystem sends REQ_DISCARD to block device whenever some data blocks are discarded. All we have to do is to handle this request. This patch implements to flag up QUEUE_FLAG_DISCARD and handle this REQ_DISCARD request. With it, we can free memory used by zram if it isn't used. [akpm@linux-foundation.org: tweak comments] Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: 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 scnprintf() in attrs show() methodsSergey Senozhatsky2014-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | sysfs.txt documentation lists the following requirements: - The buffer will always be PAGE_SIZE bytes in length. On i386, this is 4096. - show() methods should return the number of bytes printed into the buffer. This is the return value of scnprintf(). - show() should always use scnprintf(). Use scnprintf() in show() functions. Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Jerome Marchand <jmarchan@redhat.com> 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: propagate error to userMinchan Kim2014-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we initialized zcomp with single, we couldn't change max_comp_streams without zram reset but current interface doesn't show any error to user and even it changes max_comp_streams's value without any effect so it would make user very confusing. This patch prevents max_comp_streams's change when zcomp was initialized as single zcomp and emit the error to user(ex, echo). [akpm@linux-foundation.org: don't return with the lock held, per Sergey] [fengguang.wu@intel.com: fix coccinelle warnings] Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jerome Marchand <jmarchan@redhat.com> Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | zram: return error-valued pointer from zcomp_create()Sergey Senozhatsky2014-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Instead of returning just NULL, return ERR_PTR from zcomp_create() if compressing backend creation has failed. ERR_PTR(-EINVAL) for unsupported compression algorithm request, ERR_PTR(-ENOMEM) for allocation (zcomp or compression stream) error. Perform IS_ERR() check of returned from zcomp_create() value in disksize_store() and set return code to PTR_ERR(). Change suggested by Jerome Marchand. [akpm@linux-foundation.org: clean up error recovery flow] Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reported-by: Jerome Marchand <jmarchan@redhat.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | zram: move comp allocation out of init_lockSergey Senozhatsky2014-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While fixing lockdep spew of ->init_lock reported by Sasha Levin [1], Minchan Kim noted [2] that it's better to move compression backend allocation (using GPF_KERNEL) out of the ->init_lock lock, same way as with zram_meta_alloc(), in order to prevent the same lockdep spew. [1] https://lkml.org/lkml/2014/2/27/337 [2] https://lkml.org/lkml/2014/3/3/32 Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reported-by: Minchan Kim <minchan@kernel.org> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Sasha Levin <sasha.levin@oracle.com> Acked-by: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | zram: add lz4 algorithm backendSergey Senozhatsky2014-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce LZ4 compression backend and make it available for selection. LZ4 support is optional and requires user to set ZRAM_LZ4_COMPRESS config option. The default compression backend is LZO. TEST (x86_64, core i5, 2 cores + 2 hyperthreading, zram disk size 1G, ext4 file system, 3 compression streams) iozone -t 3 -R -r 16K -s 60M -I +Z Test LZO LZ4 ---------------------------------------------- Initial write 1642744.62 1317005.09 Rewrite 2498980.88 1800645.16 Read 3957026.38 5877043.75 Re-read 3950997.38 5861847.00 Reverse Read 2937114.56 5047384.00 Stride read 2948163.19 4929587.38 Random read 3292692.69 4880793.62 Mixed workload 1545602.62 3502940.38 Random write 2448039.75 1758786.25 Pwrite 1670051.03 1338329.69 Pread 2530682.00 5097177.62 Fwrite 3232085.62 3275942.56 Fread 6306880.25 6645271.12 So on my system LZ4 is slower in write-only tests, while it performs better in read-only and mixed (reads + writes) tests. Official LZ4 benchmarks available here http://code.google.com/p/lz4/ (linux kernel uses revision r90). Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Jerome Marchand <jmarchan@redhat.com> 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: make compression algorithm selection possibleSergey Senozhatsky2014-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add and document `comp_algorithm' device attribute. This attribute allows to show supported compression and currently selected compression algorithms: cat /sys/block/zram0/comp_algorithm [lzo] lz4 and change selected compression algorithm: echo lzo > /sys/block/zram0/comp_algorithm Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Jerome Marchand <jmarchan@redhat.com> 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: add set_max_streams knobSergey Senozhatsky2014-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch allows to change max_comp_streams on initialised zcomp. Introduce zcomp set_max_streams() knob, zcomp_strm_multi_set_max_streams() and zcomp_strm_single_set_max_streams() callbacks to change streams limit for zcomp_strm_multi and zcomp_strm_single, accordingly. set_max_streams for single steam zcomp does nothing. If user has lowered the limit, then zcomp_strm_multi_set_max_streams() attempts to immediately free extra streams (as much as it can, depending on idle streams availability). Note, this patch does not allow to change stream 'policy' from single to multi stream (or vice versa) on already initialised compression backend. Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Jerome Marchand <jmarchan@redhat.com> 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: add multi stream functionalitySergey Senozhatsky2014-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Existing zram (zcomp) implementation has only one compression stream (buffer and algorithm private part), so in order to prevent data corruption only one write (compress operation) can use this compression stream, forcing all concurrent write operations to wait for stream lock to be released. This patch changes zcomp to keep a compression streams list of user-defined size (via sysfs device attr). Each write operation still exclusively holds compression stream, the difference is that we can have N write operations (depending on size of streams list) executing in parallel. See TEST section later in commit message for performance data. Introduce struct zcomp_strm_multi and a set of functions to manage zcomp_strm stream access. zcomp_strm_multi has a list of idle zcomp_strm structs, spinlock to protect idle list and wait queue, making it possible to perform parallel compressions. The following set of functions added: - zcomp_strm_multi_find()/zcomp_strm_multi_release() find and release a compression stream, implement required locking - zcomp_strm_multi_create()/zcomp_strm_multi_destroy() create and destroy zcomp_strm_multi zcomp ->strm_find() and ->strm_release() callbacks are set during initialisation to zcomp_strm_multi_find()/zcomp_strm_multi_release() correspondingly. Each time zcomp issues a zcomp_strm_multi_find() call, the following set of operations performed: - spin lock strm_lock - if idle list is not empty, remove zcomp_strm from idle list, spin unlock and return zcomp stream pointer to caller - if idle list is empty, current adds itself to wait queue. it will be awaken by zcomp_strm_multi_release() caller. zcomp_strm_multi_release(): - spin lock strm_lock - add zcomp stream to idle list - spin unlock, wake up sleeper Minchan Kim reported that spinlock-based locking scheme has demonstrated a severe perfomance regression for single compression stream case, comparing to mutex-based (see https://lkml.org/lkml/2014/2/18/16) base spinlock mutex ==Initial write ==Initial write ==Initial write records: 5 records: 5 records: 5 avg: 1642424.35 avg: 699610.40 avg: 1655583.71 std: 39890.95(2.43%) std: 232014.19(33.16%) std: 52293.96 max: 1690170.94 max: 1163473.45 max: 1697164.75 min: 1568669.52 min: 573429.88 min: 1553410.23 ==Rewrite ==Rewrite ==Rewrite records: 5 records: 5 records: 5 avg: 1611775.39 avg: 501406.64 avg: 1684419.11 std: 17144.58(1.06%) std: 15354.41(3.06%) std: 18367.42 max: 1641800.95 max: 531356.78 max: 1706445.84 min: 1593515.27 min: 488817.78 min: 1655335.73 When only one compression stream available, mutex with spin on owner tends to perform much better than frequent wait_event()/wake_up(). This is why single stream implemented as a special case with mutex locking. Introduce and document zram device attribute max_comp_streams. This attr shows and stores current zcomp's max number of zcomp streams (max_strm). Extend zcomp's zcomp_create() with `max_strm' parameter. `max_strm' limits the number of zcomp_strm structs in compression backend's idle list (max_comp_streams). max_comp_streams used during initialisation as follows: -- passing to zcomp_create() max_strm equals to 1 will initialise zcomp using single compression stream zcomp_strm_single (mutex-based locking). -- passing to zcomp_create() max_strm greater than 1 will initialise zcomp using multi compression stream zcomp_strm_multi (spinlock-based locking). default max_comp_streams value is 1, meaning that zram with single stream will be initialised. Later patch will introduce configuration knob to change max_comp_streams on already initialised and used zcomp. TEST iozone -t 3 -R -r 16K -s 60M -I +Z test base 1 strm (mutex) 3 strm (spinlock) ----------------------------------------------------------------------- Initial write 589286.78 583518.39 718011.05 Rewrite 604837.97 596776.38 1515125.72 Random write 584120.11 595714.58 1388850.25 Pwrite 535731.17 541117.38 739295.27 Fwrite 1418083.88 1478612.72 1484927.06 Usage example: set max_comp_streams to 4 echo 4 > /sys/block/zram0/max_comp_streams show current max_comp_streams (default value is 1). cat /sys/block/zram0/max_comp_streams Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Jerome Marchand <jmarchan@redhat.com> 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: factor out single stream compressionSergey Senozhatsky2014-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is preparation patch to add multi stream support to zcomp. Introduce struct zcomp_strm_single and a set of functions to manage zcomp_strm stream access. zcomp_strm_single implements single compession stream, same way as current zcomp implementation. This moves zcomp_strm stream control and locking from zcomp, so compressing backend zcomp is not aware of required locking. Single and multi streams require different locking schemes. Minchan Kim reported that spinlock-based locking scheme (which is used in multi stream implementation) has demonstrated a severe perfomance regression for single compression stream case, comparing to mutex-based. see https://lkml.org/lkml/2014/2/18/16 The following set of functions added: - zcomp_strm_single_find()/zcomp_strm_single_release() find and release a compression stream, implement required locking - zcomp_strm_single_create()/zcomp_strm_single_destroy() create and destroy zcomp_strm_single New ->strm_find() and ->strm_release() callbacks added to zcomp, which are set to zcomp_strm_single_find() and zcomp_strm_single_release() during initialisation. Instead of direct locking and zcomp_strm access from zcomp_strm_find() and zcomp_strm_release(), zcomp now calls ->strm_find() and ->strm_release() correspondingly. Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Jerome Marchand <jmarchan@redhat.com> 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: use zcomp compressing backendsSergey Senozhatsky2014-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Do not perform direct LZO compress/decompress calls, initialise and use zcomp LZO backend (single compression stream) instead. [akpm@linux-foundation.org: resolve conflicts with zram-delete-zram_init_device-fix.patch] Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Jerome Marchand <jmarchan@redhat.com> 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: introduce compressing backend abstractionSergey Senozhatsky2014-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ZRAM performs direct LZO compression algorithm calls, making it the one and only option. While LZO is generally performs well, LZ4 algorithm tends to have a faster decompression (see http://code.google.com/p/lz4/ for full report) Name Ratio C.speed D.speed MB/s MB/s LZ4 (r101) 2.084 422 1820 LZO 2.06 2.106 414 600 Thus, users who have mostly read (decompress) usage scenarious or mixed workflow (writes with relatively high read ops number) will benefit from using LZ4 compression backend. Introduce compressing backend abstraction zcomp in order to support multiple compression algorithms with the following set of operations: .create .destroy .compress .decompress Schematically zram write() usually contains the following steps: 0) preparation (decompression of partioal IO, etc.) 1) lock buffer_lock mutex (protects meta compress buffers) 2) compress (using meta compress buffers) 3) alloc and map zs_pool object 4) copy compressed data (from meta compress buffers) to object allocated by 3) 5) free previous pool page, assign a new one 6) unlock buffer_lock mutex As we can see, compressing buffers must remain untouched from 1) to 4), because, otherwise, concurrent write() can overwrite data. At the same time, zram_meta must be aware of a) specific compression algorithm memory requirements and b) necessary locking to protect compression buffers. To remove requirement a) new struct zcomp_strm introduced, which contains a compress/decompress `buffer' and compression algorithm `private' part. While struct zcomp implements zcomp_strm stream handling and locking and removes requirement b) from zram meta. zcomp ->create() and ->destroy(), respectively, allocate and deallocate algorithm specific zcomp_strm `private' part. Every zcomp has zcomp stream and mutex to protect its compression stream. Stream usage semantics remains the same -- only one write can hold stream lock and use its buffers. zcomp_strm_find() turns caller into exclusive user of a stream (holding stream mutex until zram release stream), and zcomp_strm_release() makes zcomp stream available (unlock the stream mutex). Hence no concurrent write (compression) operations possible at the moment. iozone -t 3 -R -r 16K -s 60M -I +Z test base patched -------------------------------------------------- Initial write 597992.91 591660.58 Rewrite 609674.34 616054.97 Read 2404771.75 2452909.12 Re-read 2459216.81 2470074.44 Reverse Read 1652769.66 1589128.66 Stride read 2202441.81 2202173.31 Random read 2236311.47 2276565.31 Mixed workload 1423760.41 1709760.06 Random write 579584.08 615933.86 Pwrite 597550.02 594933.70 Pread 1703672.53 1718126.72 Fwrite 1330497.06 1461054.00 Fread 3922851.00 3957242.62 Usage examples: comp = zcomp_create(NAME) /* NAME e.g. "lzo" */ which initialises compressing backend if requested algorithm is supported. Compress: zstrm = zcomp_strm_find(comp) zcomp_compress(comp, zstrm, src, &dst_len) [..] /* copy compressed data */ zcomp_strm_release(comp, zstrm) Decompress: zcomp_decompress(comp, src, src_len, dst); Free compessing backend and its zcomp stream: zcomp_destroy(comp) Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Jerome Marchand <jmarchan@redhat.com> 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: delete zram_init_device()Sergey Senozhatsky2014-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | allocate new `zram_meta' in disksize_store() only for uninitialised zram device, saving a number of allocations and deallocations in case if disksize_store() was called on currently used device. at the same time zram_meta stack variable is not necessary, because we can set ->meta directly. there is also no need in setting QUEUE_FLAG_NONROT queue on every disksize_store(), set it once during device creation. [minchan@kernel.org: handle zram->meta alloc fail case] [minchan@kernel.org: prevent lockdep spew of init_lock] Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Minchan Kim <minchan@kernel.org> Acked-by: Jerome Marchand <jmarchan@redhat.com> Cc: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | zram: move zram size warning to documentationSergey Senozhatsky2014-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move zram warning about disksize and size of memory correlation to zram documentation. Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Jerome Marchand <jmarchan@redhat.com> 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: drop not used table `count' memberSergey Senozhatsky2014-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | struct table `count' member is not used. Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Minchan Kim <minchan@kernel.org> Acked-by: Jerome Marchand <jmarchan@redhat.com> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>