1. 10 Mar, 2021 1 commit
    • Clement Courbet's avatar
      sched: Optimize __calc_delta() · 1e17fb8e
      Clement Courbet authored
      A significant portion of __calc_delta() time is spent in the loop
      shifting a u64 by 32 bits. Use `fls` instead of iterating.
      
      This is ~7x faster on benchmarks.
      
      The generic `fls` implementation (`generic_fls`) is still ~4x faster
      than the loop.
      Architectures that have a better implementation will make use of it. For
      example, on x86 we get an additional factor 2 in speed without dedicated
      implementation.
      
      On GCC, the asm versions of `fls` are about the same speed as the
      builtin. On Clang, the versions that use fls are more than twice as
      slow as the builtin. This is because the way the `fls` function is
      written, clang puts the value in memory:
      https://godbolt.org/z/EfMbYe. This bug is filed at
      https://bugs.llvm.org/show_bug.cgi?idI406.
      
      ```
      name                                   cpu/op
      BM_Calc<__calc_delta_loop>             9.57ms Â=B112%
      BM_Calc<__calc_delta_generic_fls>      2.36ms Â=B113%
      BM_Calc<__calc_delta_asm_fls>          2.45ms Â=B113%
      BM_Calc<__calc_delta_asm_fls_nomem>    1.66ms Â=B112%
      BM_Calc<__calc_delta_asm_fls64>        2.46ms Â=B113%
      BM_Calc<__calc_delta_asm_fls64_nomem>  1.34ms Â=B115%
      BM_Calc<__calc_delta_builtin>          1.32ms Â=B111%
      ```
      Signed-off-by: default avatarClement Courbet <courbet@google.com>
      Signed-off-by: default avatarJosh Don <joshdon@google.com>
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Link: https://lkml.kernel.org/r/20210303224653.2579656-1-joshdon@google.com
      1e17fb8e
  2. 06 Mar, 2021 32 commits
  3. 05 Mar, 2021 7 commits
    • Linus Torvalds's avatar
      Merge tag 'for-5.12/dm-fixes' of... · 63dcd69d
      Linus Torvalds authored
      Merge tag 'for-5.12/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
      
      Pull device mapper fixes from Mike Snitzer:
       "Fix DM verity target's optional Forward Error Correction (FEC) for
        Reed-Solomon roots that are unaligned to block size"
      
      * tag 'for-5.12/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
        dm verity: fix FEC for RS roots unaligned to block size
        dm bufio: subtract the number of initial sectors in dm_bufio_get_device_size
      63dcd69d
    • Linus Torvalds's avatar
      Merge tag 'block-5.12-2021-03-05' of git://git.kernel.dk/linux-block · 47454caf
      Linus Torvalds authored
      Pull block fixes from Jens Axboe:
      
       - NVMe fixes:
            - more device quirks (Julian Einwag, Zoltán Böszörményi, Pascal
              Terjan)
            - fix a hwmon error return (Daniel Wagner)
            - fix the keep alive timeout initialization (Martin George)
            - ensure the model_number can't be changed on a used subsystem
              (Max Gurtovoy)
      
       - rsxx missing -EFAULT on copy_to_user() failure (Dan)
      
       - rsxx remove unused linux.h include (Tian)
      
       - kill unused RQF_SORTED (Jean)
      
       - updated outdated BFQ comments (Joseph)
      
       - revert work-around commit for bd_size_lock, since we removed the
         offending user in this merge window (Damien)
      
      * tag 'block-5.12-2021-03-05' of git://git.kernel.dk/linux-block:
        nvmet: model_number must be immutable once set
        nvme-fabrics: fix kato initialization
        nvme-hwmon: Return error code when registration fails
        nvme-pci: add quirks for Lexar 256GB SSD
        nvme-pci: mark Kingston SKC2000 as not supporting the deepest power state
        nvme-pci: mark Seagate Nytro XM1440 as QUIRK_NO_NS_DESC_LIST.
        rsxx: Return -EFAULT if copy_to_user() fails
        block/bfq: update comments and default value in docs for fifo_expire
        rsxx: remove unused including <linux/version.h>
        block: Drop leftover references to RQF_SORTED
        block: revert "block: fix bd_size_lock use"
      47454caf
    • Linus Torvalds's avatar
      Merge tag 'io_uring-5.12-2021-03-05' of git://git.kernel.dk/linux-block · f292e873
      Linus Torvalds authored
      Pull io_uring fixes from Jens Axboe:
       "A bit of a mix between fallout from the worker change, cleanups and
        reductions now possible from that change, and fixes in general. In
        detail:
      
         - Fully serialize manager and worker creation, fixing races due to
           that.
      
         - Clean up some naming that had gone stale.
      
         - SQPOLL fixes.
      
         - Fix race condition around task_work rework that went into this
           merge window.
      
         - Implement unshare. Used for when the original task does unshare(2)
           or setuid/seteuid and friends, drops the original workers and forks
           new ones.
      
         - Drop the only remaining piece of state shuffling we had left, which
           was cred. Move it into issue instead, and we can drop all of that
           code too.
      
         - Kill f_op->flush() usage. That was such a nasty hack that we had
           out of necessity, we no longer need it.
      
         - Following from ->flush() removal, we can also drop various bits of
           ctx state related to SQPOLL and cancelations.
      
         - Fix an issue with IOPOLL retry, which originally was fallout from a
           filemap change (removing iov_iter_revert()), but uncovered an issue
           with iovec re-import too late.
      
         - Fix an issue with system suspend.
      
         - Use xchg() for fallback work, instead of cmpxchg().
      
         - Properly destroy io-wq on exec.
      
         - Add create_io_thread() core helper, and use that in io-wq and
           io_uring. This allows us to remove various silly completion events
           related to thread setup.
      
         - A few error handling fixes.
      
        This should be the grunt of fixes necessary for the new workers, next
        week should be quieter. We've got a pending series from Pavel on
        cancelations, and how tasks and rings are indexed. Outside of that,
        should just be minor fixes. Even with these fixes, we're still killing
        a net ~80 lines"
      
      * tag 'io_uring-5.12-2021-03-05' of git://git.kernel.dk/linux-block: (41 commits)
        io_uring: don't restrict issue_flags for io_openat
        io_uring: make SQPOLL thread parking saner
        io-wq: kill hashed waitqueue before manager exits
        io_uring: clear IOCB_WAITQ for non -EIOCBQUEUED return
        io_uring: don't keep looping for more events if we can't flush overflow
        io_uring: move to using create_io_thread()
        kernel: provide create_io_thread() helper
        io_uring: reliably cancel linked timeouts
        io_uring: cancel-match based on flags
        io-wq: ensure all pending work is canceled on exit
        io_uring: ensure that threads freeze on suspend
        io_uring: remove extra in_idle wake up
        io_uring: inline __io_queue_async_work()
        io_uring: inline io_req_clean_work()
        io_uring: choose right tctx->io_wq for try cancel
        io_uring: fix -EAGAIN retry with IOPOLL
        io-wq: fix error path leak of buffered write hash map
        io_uring: remove sqo_task
        io_uring: kill sqo_dead and sqo submission halting
        io_uring: ignore double poll add on the same waitqueue head
        ...
      f292e873
    • Linus Torvalds's avatar
      Merge tag 'pm-5.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm · 6d47254c
      Linus Torvalds authored
      Pull power management fixes from Rafael Wysocki:
       "These fix the usage of device links in the runtime PM core code and
        update the DTPM (Dynamic Thermal Power Management) feature added
        recently.
      
        Specifics:
      
         - Make the runtime PM core code avoid attempting to suspend supplier
           devices before updating the PM-runtime status of a consumer to
           'suspended' (Rafael Wysocki).
      
         - Fix DTPM (Dynamic Thermal Power Management) root node
           initialization and label that feature as EXPERIMENTAL in Kconfig
           (Daniel Lezcano)"
      
      * tag 'pm-5.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
        powercap/drivers/dtpm: Add the experimental label to the option description
        powercap/drivers/dtpm: Fix root node initialization
        PM: runtime: Update device status before letting suppliers suspend
      6d47254c
    • Linus Torvalds's avatar
      Merge tag 'acpi-5.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm · ea6be461
      Linus Torvalds authored
      Pull ACPI fix from Rafael Wysocki:
       "Make the empty stubs of some helper functions used when CONFIG_ACPI is
        not set actually match those functions (Andy Shevchenko)"
      
      * tag 'acpi-5.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
        ACPI: bus: Constify is_acpi_node() and friends (part 2)
      ea6be461
    • Linus Torvalds's avatar
      Merge tag 'iommu-fixes-v5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu · fc2c8d0a
      Linus Torvalds authored
      Pull iommu fixes from Joerg Roedel:
      
       - Fix a sleeping-while-atomic issue in the AMD IOMMU code
      
       - Disable lazy IOTLB flush for untrusted devices in the Intel VT-d
         driver
      
       - Fix status code definitions for Intel VT-d
      
       - Fix IO Page Fault issue in Tegra IOMMU driver
      
      * tag 'iommu-fixes-v5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
        iommu/vt-d: Fix status code for Allocate/Free PASID command
        iommu: Don't use lazy flush for untrusted device
        iommu/tegra-smmu: Fix mc errors on tegra124-nyan
        iommu/amd: Fix sleeping in atomic in increase_address_space()
      fc2c8d0a
    • Linus Torvalds's avatar
      Merge tag 'for-5.12-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux · f09b04cc
      Linus Torvalds authored
      Pull btrfs fixes from David Sterba:
       "More regression fixes and stabilization.
      
        Regressions:
      
         - zoned mode
            - count zone sizes in wider int types
            - fix space accounting for read-only block groups
      
         - subpage: fix page tail zeroing
      
        Fixes:
      
         - fix spurious warning when remounting with free space tree
      
         - fix warning when creating a directory with smack enabled
      
         - ioctl checks for qgroup inheritance when creating a snapshot
      
         - qgroup
            - fix missing unlock on error path in zero range
            - fix amount of released reservation on error
            - fix flushing from unsafe context with open transaction,
              potentially deadlocking
      
         - minor build warning fixes"
      
      * tag 'for-5.12-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
        btrfs: zoned: do not account freed region of read-only block group as zone_unusable
        btrfs: zoned: use sector_t for zone sectors
        btrfs: subpage: fix the false data csum mismatch error
        btrfs: fix warning when creating a directory with smack enabled
        btrfs: don't flush from btrfs_delayed_inode_reserve_metadata
        btrfs: export and rename qgroup_reserve_meta
        btrfs: free correct amount of space in btrfs_delayed_inode_reserve_metadata
        btrfs: fix spurious free_space_tree remount warning
        btrfs: validate qgroup inherit for SNAP_CREATE_V2 ioctl
        btrfs: unlock extents in btrfs_zero_range in case of quota reservation errors
        btrfs: ref-verify: use 'inline void' keyword ordering
      f09b04cc