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* [RFC PATCH 00/20] Remove Mysterious Macro Intended to Obscure Weird Behaviours (mmiowb())
@ 2019-02-22 18:50 Will Deacon
  2019-02-22 18:50 ` [RFC PATCH 01/20] asm-generic/mmiowb: Add generic implementation of mmiowb() tracking Will Deacon
                   ` (19 more replies)
  0 siblings, 20 replies; 31+ messages in thread
From: Will Deacon @ 2019-02-22 18:50 UTC (permalink / raw)
  To: linux-arch
  Cc: linux-kernel, Will Deacon, Paul E. McKenney,
	Benjamin Herrenschmidt, Michael Ellerman, Arnd Bergmann,
	Peter Zijlstra, Andrea Parri, Palmer Dabbelt, Daniel Lustig,
	David Howells, Alan Stern, Linus Torvalds, Maciej W. Rozycki,
	Paul Burton, Ingo Molnar, Yoshinori Sato, Rich Felker, Tony Luck

Hi all,

This series attempts to remove explicit mmiowb() calls from driver code,
instead adding it to spin_unlock() for architectures that require it.

The infamous "PowerPC trick" was found to be flawed, so a correct but probably
slower version is made generic for architectures wishing to use it. I've ported
RISC-V over to this interface, and hooked up PowerPC to the generic
infrastructure but with their existing implementation. Other architectures that
require a definition for mmiowb() now have it unconditionally called from their
spin_unlock() code. If this is deemed to be expensive, they should be able to
do something similar to RISC-V.

I used coccinelle to remove the vast majority of the users, and the trivial
spatch invocation is included in the commit message of that patch. I've also
*build-tested* this for RISC-V, ia64, mips64, sh, powerpc64 and arm64.

This is based on a couple of other I/O-related series that I have pending:

  https://lkml.org/lkml/2019/2/22/484
  https://lkml.org/lkml/2019/2/22/500

so I've pushed the whole lot out on a branch for your comfort and convenience:

  git://git.kernel.org/pub/scm/linux/kernel/git/will/linux.git io

Feedback welcome,

Will

Cc: "Paul E. McKenney" <paulmck@linux.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrea Parri <andrea.parri@amarulasolutions.com>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Daniel Lustig <dlustig@nvidia.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "Maciej W. Rozycki" <macro@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Tony Luck <tony.luck@intel.com>

--->8

Will Deacon (20):
  asm-generic/mmiowb: Add generic implementation of mmiowb() tracking
  arch: Use asm-generic header for asm/mmiowb.h
  mmiowb: Hook up mmiowb helpers to spinlocks and generic I/O accessors
  ARM: io: Remove useless definition of mmiowb()
  arm64: io: Remove useless definition of mmiowb()
  x86: io: Remove useless definition of mmiowb()
  nds32: io: Remove useless definition of mmiowb()
  m68k: io: Remove useless definition of mmiowb()
  sh: Add unconditional mmiowb() to arch_spin_unlock()
  mips: Add unconditional mmiowb() to arch_spin_unlock()
  ia64: Add unconditional mmiowb() to arch_spin_unlock()
  powerpc: mmiowb: Hook up mmwiob() implementation to asm-generic code
  riscv: mmiowb: Hook up mmwiob() implementation to asm-generic code
  Documentation: Kill all references to mmiowb()
  drivers: Remove useless trailing comments from mmiowb() invocations
  drivers: Remove explicit invocations of mmiowb()
  scsi: qla1280: Remove stale comment about mmiowb()
  i40iw: Redefine i40iw_mmiowb() to do nothing
  net: silan: sc92031: Remove stale comment about mmiowb()
  arch: Remove dummy mmiowb() definitions from arch code

 Documentation/driver-api/device-io.rst             |  45 ---------
 Documentation/driver-api/pci/p2pdma.rst            |   4 -
 Documentation/memory-barriers.txt                  | 103 +--------------------
 arch/alpha/include/asm/Kbuild                      |   1 +
 arch/alpha/include/asm/io.h                        |   2 -
 arch/arc/include/asm/Kbuild                        |   1 +
 arch/arm/include/asm/Kbuild                        |   1 +
 arch/arm/include/asm/io.h                          |   2 -
 arch/arm64/include/asm/Kbuild                      |   1 +
 arch/arm64/include/asm/io.h                        |   2 -
 arch/c6x/include/asm/Kbuild                        |   1 +
 arch/csky/include/asm/Kbuild                       |   1 +
 arch/h8300/include/asm/Kbuild                      |   1 +
 arch/hexagon/include/asm/Kbuild                    |   1 +
 arch/hexagon/include/asm/io.h                      |   2 -
 arch/ia64/include/asm/io.h                         |   4 -
 arch/ia64/include/asm/mmiowb.h                     |  12 +++
 arch/ia64/include/asm/spinlock.h                   |   2 +
 arch/m68k/include/asm/Kbuild                       |   1 +
 arch/m68k/include/asm/io_mm.h                      |   2 -
 arch/microblaze/include/asm/Kbuild                 |   1 +
 arch/mips/include/asm/io.h                         |   3 -
 arch/mips/include/asm/mmiowb.h                     |  11 +++
 arch/mips/include/asm/spinlock.h                   |  15 +++
 arch/nds32/include/asm/Kbuild                      |   1 +
 arch/nds32/include/asm/io.h                        |   2 -
 arch/nios2/include/asm/Kbuild                      |   1 +
 arch/openrisc/include/asm/Kbuild                   |   1 +
 arch/parisc/include/asm/Kbuild                     |   1 +
 arch/parisc/include/asm/io.h                       |   2 -
 arch/powerpc/Kconfig                               |   1 +
 arch/powerpc/include/asm/io.h                      |  33 +------
 arch/powerpc/include/asm/mmiowb.h                  |  41 ++++++++
 arch/powerpc/include/asm/spinlock.h                |  17 ----
 arch/riscv/Kconfig                                 |   1 +
 arch/riscv/include/asm/io.h                        |  15 +--
 arch/riscv/include/asm/mmiowb.h                    |  14 +++
 arch/s390/include/asm/Kbuild                       |   1 +
 arch/sh/include/asm/io.h                           |   3 -
 arch/sh/include/asm/mmiowb.h                       |  12 +++
 arch/sh/include/asm/spinlock-llsc.h                |   2 +
 arch/sparc/include/asm/Kbuild                      |   1 +
 arch/sparc/include/asm/io_64.h                     |   2 -
 arch/um/include/asm/Kbuild                         |   1 +
 arch/unicore32/include/asm/Kbuild                  |   1 +
 arch/x86/include/asm/io.h                          |   2 -
 arch/xtensa/include/asm/Kbuild                     |   1 +
 drivers/crypto/cavium/nitrox/nitrox_reqmgr.c       |   4 -
 drivers/dma/txx9dmac.c                             |   3 -
 drivers/firewire/ohci.c                            |   1 -
 drivers/gpu/drm/i915/intel_hdmi.c                  |  10 --
 drivers/ide/tx4939ide.c                            |   2 -
 drivers/infiniband/hw/hfi1/chip.c                  |   3 -
 drivers/infiniband/hw/hfi1/pio.c                   |   1 -
 drivers/infiniband/hw/hns/hns_roce_hw_v1.c         |   2 -
 drivers/infiniband/hw/i40iw/i40iw_osdep.h          |   2 +-
 drivers/infiniband/hw/mlx4/qp.c                    |   6 --
 drivers/infiniband/hw/mlx5/qp.c                    |   1 -
 drivers/infiniband/hw/mthca/mthca_cmd.c            |   6 --
 drivers/infiniband/hw/mthca/mthca_cq.c             |   5 -
 drivers/infiniband/hw/mthca/mthca_qp.c             |  17 ----
 drivers/infiniband/hw/mthca/mthca_srq.c            |   6 --
 drivers/infiniband/hw/qedr/verbs.c                 |  12 ---
 drivers/infiniband/hw/qib/qib_iba6120.c            |   4 -
 drivers/infiniband/hw/qib/qib_iba7220.c            |   3 -
 drivers/infiniband/hw/qib/qib_iba7322.c            |   3 -
 drivers/infiniband/hw/qib/qib_sd7220.c             |   4 -
 drivers/media/pci/dt3155/dt3155.c                  |   8 --
 drivers/memstick/host/jmb38x_ms.c                  |   4 -
 drivers/misc/ioc4.c                                |   2 -
 drivers/misc/mei/hw-me.c                           |   3 -
 drivers/misc/tifm_7xx1.c                           |   1 -
 drivers/mmc/host/alcor.c                           |   1 -
 drivers/mmc/host/sdhci.c                           |  13 ---
 drivers/mmc/host/tifm_sd.c                         |   3 -
 drivers/mmc/host/via-sdmmc.c                       |  10 --
 drivers/mtd/nand/raw/r852.c                        |   2 -
 drivers/mtd/nand/raw/txx9ndfmc.c                   |   1 -
 drivers/net/ethernet/aeroflex/greth.c              |   1 -
 drivers/net/ethernet/alacritech/slicoss.c          |   4 -
 drivers/net/ethernet/amazon/ena/ena_com.c          |   1 -
 drivers/net/ethernet/atheros/atlx/atl1.c           |   1 -
 drivers/net/ethernet/atheros/atlx/atl2.c           |   1 -
 drivers/net/ethernet/broadcom/bnx2.c               |   4 -
 drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c    |   2 -
 drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.h    |   4 -
 .../net/ethernet/broadcom/bnx2x/bnx2x_ethtool.c    |   1 -
 drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c   |  29 ------
 drivers/net/ethernet/broadcom/bnx2x/bnx2x_sp.c     |   1 -
 drivers/net/ethernet/broadcom/bnx2x/bnx2x_sriov.c  |   2 -
 drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c   |   4 -
 drivers/net/ethernet/broadcom/bnxt/bnxt.c          |   3 -
 drivers/net/ethernet/broadcom/tg3.c                |   6 --
 .../net/ethernet/cavium/liquidio/cn66xx_device.c   |  10 --
 .../net/ethernet/cavium/liquidio/octeon_device.c   |   1 -
 drivers/net/ethernet/cavium/liquidio/octeon_droq.c |   4 -
 .../net/ethernet/cavium/liquidio/request_manager.c |   1 -
 drivers/net/ethernet/intel/e1000/e1000_main.c      |   5 -
 drivers/net/ethernet/intel/e1000e/netdev.c         |   7 --
 drivers/net/ethernet/intel/fm10k/fm10k_iov.c       |   2 -
 drivers/net/ethernet/intel/fm10k/fm10k_main.c      |   5 -
 drivers/net/ethernet/intel/i40e/i40e_txrx.c        |   5 -
 drivers/net/ethernet/intel/iavf/iavf_txrx.c        |   5 -
 drivers/net/ethernet/intel/ice/ice_txrx.c          |   5 -
 drivers/net/ethernet/intel/igb/igb_main.c          |   5 -
 drivers/net/ethernet/intel/igbvf/netdev.c          |   4 -
 drivers/net/ethernet/intel/igc/igc_main.c          |   5 -
 drivers/net/ethernet/intel/ixgbe/ixgbe_main.c      |   5 -
 drivers/net/ethernet/marvell/sky2.c                |   4 -
 drivers/net/ethernet/mellanox/mlx4/catas.c         |   4 -
 drivers/net/ethernet/mellanox/mlx4/cmd.c           |  13 ---
 drivers/net/ethernet/mellanox/mlx5/core/cmd.c      |   1 -
 drivers/net/ethernet/myricom/myri10ge/myri10ge.c   |   2 -
 drivers/net/ethernet/neterion/s2io.c               |   2 -
 drivers/net/ethernet/neterion/vxge/vxge-main.c     |   5 -
 drivers/net/ethernet/neterion/vxge/vxge-traffic.c  |   4 -
 drivers/net/ethernet/qlogic/qed/qed_int.c          |  13 ---
 drivers/net/ethernet/qlogic/qed/qed_spq.c          |   3 -
 drivers/net/ethernet/qlogic/qede/qede_ethtool.c    |   8 --
 drivers/net/ethernet/qlogic/qede/qede_fp.c         |   8 --
 drivers/net/ethernet/qlogic/qla3xxx.c              |   1 -
 drivers/net/ethernet/qlogic/qlge/qlge.h            |   1 -
 drivers/net/ethernet/qlogic/qlge/qlge_main.c       |   1 -
 drivers/net/ethernet/realtek/r8169.c               |   5 -
 drivers/net/ethernet/renesas/ravb_main.c           |   9 --
 drivers/net/ethernet/renesas/ravb_ptp.c            |   3 -
 drivers/net/ethernet/renesas/sh_eth.c              |   1 -
 drivers/net/ethernet/sfc/falcon/io.h               |   2 -
 drivers/net/ethernet/sfc/io.h                      |   2 -
 drivers/net/ethernet/silan/sc92031.c               |  15 ---
 drivers/net/ethernet/via/via-rhine.c               |   3 -
 drivers/net/ethernet/wiznet/w5100.c                |   6 --
 drivers/net/ethernet/wiznet/w5300.c                |  15 ---
 drivers/net/wireless/ath/ath5k/base.c              |   4 -
 drivers/net/wireless/ath/ath5k/mac80211-ops.c      |   2 -
 drivers/net/wireless/broadcom/b43/main.c           |   7 --
 drivers/net/wireless/broadcom/b43/sysfs.c          |   1 -
 drivers/net/wireless/broadcom/b43legacy/ilt.c      |   2 -
 drivers/net/wireless/broadcom/b43legacy/main.c     |  20 ----
 drivers/net/wireless/broadcom/b43legacy/phy.c      |   1 -
 drivers/net/wireless/broadcom/b43legacy/pio.h      |   1 -
 drivers/net/wireless/broadcom/b43legacy/radio.c    |   4 -
 drivers/net/wireless/broadcom/b43legacy/sysfs.c    |   1 -
 drivers/net/wireless/intel/iwlegacy/common.h       |   7 --
 drivers/net/wireless/intel/iwlwifi/pcie/trans.c    |   1 -
 drivers/ntb/hw/idt/ntb_hw_idt.c                    |   7 --
 drivers/ntb/test/ntb_perf.c                        |   3 -
 drivers/scsi/bfa/bfa.h                             |   3 +-
 drivers/scsi/bfa/bfa_hw_cb.c                       |   2 -
 drivers/scsi/bfa/bfa_hw_ct.c                       |   2 -
 drivers/scsi/bnx2fc/bnx2fc_hwi.c                   |   2 -
 drivers/scsi/bnx2i/bnx2i_hwi.c                     |   3 -
 drivers/scsi/megaraid/megaraid_sas_base.c          |   1 -
 drivers/scsi/megaraid/megaraid_sas_fusion.c        |   1 -
 drivers/scsi/mpt3sas/mpt3sas_base.c                |   1 -
 drivers/scsi/qedf/qedf_io.c                        |   1 -
 drivers/scsi/qedi/qedi_fw.c                        |   1 -
 drivers/scsi/qla1280.c                             |  15 ---
 drivers/ssb/pci.c                                  |   1 -
 drivers/ssb/pcmcia.c                               |   4 -
 drivers/staging/comedi/drivers/mite.c              |   3 -
 drivers/staging/comedi/drivers/ni_660x.c           |   2 -
 drivers/staging/comedi/drivers/ni_mio_common.c     |   1 -
 drivers/staging/comedi/drivers/ni_pcidio.c         |   2 -
 drivers/staging/comedi/drivers/ni_tio.c            |   1 -
 drivers/staging/comedi/drivers/s626.c              |   2 -
 drivers/tty/serial/men_z135_uart.c                 |   1 -
 drivers/tty/serial/serial_txx9.c                   |   1 -
 drivers/usb/early/xhci-dbc.c                       |   4 -
 drivers/usb/host/xhci-dbgcap.c                     |   2 -
 include/asm-generic/io.h                           |   3 +-
 include/asm-generic/mmiowb.h                       |  60 ++++++++++++
 include/linux/qed/qed_if.h                         |   2 -
 include/linux/spinlock.h                           |  11 ++-
 kernel/Kconfig.locks                               |   3 +
 kernel/locking/spinlock.c                          |   5 +
 kernel/locking/spinlock_debug.c                    |   6 +-
 sound/soc/txx9/txx9aclc-ac97.c                     |   1 -
 178 files changed, 226 insertions(+), 764 deletions(-)
 create mode 100644 arch/ia64/include/asm/mmiowb.h
 create mode 100644 arch/mips/include/asm/mmiowb.h
 create mode 100644 arch/powerpc/include/asm/mmiowb.h
 create mode 100644 arch/riscv/include/asm/mmiowb.h
 create mode 100644 arch/sh/include/asm/mmiowb.h
 create mode 100644 include/asm-generic/mmiowb.h

-- 
2.11.0


^ permalink raw reply	[flat|nested] 31+ messages in thread

end of thread, other threads:[~2019-02-27 10:20 UTC | newest]

Thread overview: 31+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-02-22 18:50 [RFC PATCH 00/20] Remove Mysterious Macro Intended to Obscure Weird Behaviours (mmiowb()) Will Deacon
2019-02-22 18:50 ` [RFC PATCH 01/20] asm-generic/mmiowb: Add generic implementation of mmiowb() tracking Will Deacon
2019-02-22 21:49   ` Linus Torvalds
2019-02-22 21:55     ` Linus Torvalds
2019-02-26 18:25       ` Will Deacon
2019-02-26 18:26     ` Will Deacon
2019-02-26 18:33       ` Peter Zijlstra
2019-02-26 19:02         ` Linus Torvalds
2019-02-27 10:19           ` Peter Zijlstra
2019-02-22 18:50 ` [RFC PATCH 02/20] arch: Use asm-generic header for asm/mmiowb.h Will Deacon
2019-02-22 18:50 ` [RFC PATCH 03/20] mmiowb: Hook up mmiowb helpers to spinlocks and generic I/O accessors Will Deacon
2019-02-22 18:50 ` [RFC PATCH 04/20] ARM: io: Remove useless definition of mmiowb() Will Deacon
2019-02-22 18:50 ` [RFC PATCH 05/20] arm64: " Will Deacon
2019-02-22 18:50 ` [RFC PATCH 06/20] x86: " Will Deacon
2019-02-22 18:50 ` [RFC PATCH 07/20] nds32: " Will Deacon
2019-02-22 18:50 ` [RFC PATCH 08/20] m68k: " Will Deacon
2019-02-25  9:25   ` Geert Uytterhoeven
2019-02-25 12:12     ` Will Deacon
2019-02-22 18:50 ` [RFC PATCH 09/20] sh: Add unconditional mmiowb() to arch_spin_unlock() Will Deacon
2019-02-22 18:50 ` [RFC PATCH 10/20] mips: " Will Deacon
2019-02-22 18:50 ` [RFC PATCH 11/20] ia64: " Will Deacon
2019-02-27  4:36   ` Nicholas Piggin
2019-02-22 18:50 ` [RFC PATCH 12/20] powerpc: mmiowb: Hook up mmwiob() implementation to asm-generic code Will Deacon
2019-02-22 18:50 ` [RFC PATCH 13/20] riscv: " Will Deacon
2019-02-22 18:50 ` [RFC PATCH 14/20] Documentation: Kill all references to mmiowb() Will Deacon
2019-02-22 18:50 ` [RFC PATCH 15/20] drivers: Remove useless trailing comments from mmiowb() invocations Will Deacon
2019-02-22 18:50 ` [RFC PATCH 16/20] drivers: Remove explicit invocations of mmiowb() Will Deacon
2019-02-22 18:50 ` [RFC PATCH 17/20] scsi: qla1280: Remove stale comment about mmiowb() Will Deacon
2019-02-22 18:50 ` [RFC PATCH 18/20] i40iw: Redefine i40iw_mmiowb() to do nothing Will Deacon
2019-02-22 18:50 ` [RFC PATCH 19/20] net: silan: sc92031: Remove stale comment about mmiowb() Will Deacon
2019-02-22 18:50 ` [RFC PATCH 20/20] arch: Remove dummy mmiowb() definitions from arch code Will Deacon

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