1. 16 11月, 2016 2 次提交
    • C
      locking/core, arch: Remove cpu_relax_lowlatency() · 5bd0b85b
      Christian Borntraeger 提交于
      As there are no users left, we can remove cpu_relax_lowlatency()
      implementations from every architecture.
      Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Nicholas Piggin <npiggin@gmail.com>
      Cc: Noam Camus <noamc@ezchip.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: linuxppc-dev@lists.ozlabs.org
      Cc: virtualization@lists.linux-foundation.org
      Cc: xen-devel@lists.xenproject.org
      Cc: <linux-arch@vger.kernel.org>
      Link: http://lkml.kernel.org/r/1477386195-32736-6-git-send-email-borntraeger@de.ibm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      5bd0b85b
    • C
      locking/core: Introduce cpu_relax_yield() · 79ab11cd
      Christian Borntraeger 提交于
      For spinning loops people do often use barrier() or cpu_relax().
      For most architectures cpu_relax and barrier are the same, but on
      some architectures cpu_relax can add some latency.
      For example on power,sparc64 and arc, cpu_relax can shift the CPU
      towards other hardware threads in an SMT environment.
      On s390 cpu_relax does even more, it uses an hypercall to the
      hypervisor to give up the timeslice.
      In contrast to the SMT yielding this can result in larger latencies.
      In some places this latency is unwanted, so another variant
      "cpu_relax_lowlatency" was introduced. Before this is used in more
      and more places, lets revert the logic and provide a cpu_relax_yield
      that can be called in places where yielding is more important than
      latency. By default this is the same as cpu_relax on all architectures.
      Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Nicholas Piggin <npiggin@gmail.com>
      Cc: Noam Camus <noamc@ezchip.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: linuxppc-dev@lists.ozlabs.org
      Cc: virtualization@lists.linux-foundation.org
      Cc: xen-devel@lists.xenproject.org
      Link: http://lkml.kernel.org/r/1477386195-32736-2-git-send-email-borntraeger@de.ibm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      79ab11cd
  2. 25 10月, 2016 1 次提交
  3. 14 9月, 2016 1 次提交
  4. 16 6月, 2016 2 次提交
  5. 14 6月, 2016 1 次提交
    • P
      locking/spinlock, arch: Update and fix spin_unlock_wait() implementations · 726328d9
      Peter Zijlstra 提交于
      This patch updates/fixes all spin_unlock_wait() implementations.
      
      The update is in semantics; where it previously was only a control
      dependency, we now upgrade to a full load-acquire to match the
      store-release from the spin_unlock() we waited on. This ensures that
      when spin_unlock_wait() returns, we're guaranteed to observe the full
      critical section we waited on.
      
      This fixes a number of spin_unlock_wait() users that (not
      unreasonably) rely on this.
      
      I also fixed a number of ticket lock versions to only wait on the
      current lock holder, instead of for a full unlock, as this is
      sufficient.
      
      Furthermore; again for ticket locks; I added an smp_rmb() in between
      the initial ticket load and the spin loop testing the current value
      because I could not convince myself the address dependency is
      sufficient, esp. if the loads are of different sizes.
      
      I'm more than happy to remove this smp_rmb() again if people are
      certain the address dependency does indeed work as expected.
      
      Note: PPC32 will be fixed independently
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: chris@zankel.net
      Cc: cmetcalf@mellanox.com
      Cc: davem@davemloft.net
      Cc: dhowells@redhat.com
      Cc: james.hogan@imgtec.com
      Cc: jejb@parisc-linux.org
      Cc: linux@armlinux.org.uk
      Cc: mpe@ellerman.id.au
      Cc: ralf@linux-mips.org
      Cc: realmz6@gmail.com
      Cc: rkuo@codeaurora.org
      Cc: rth@twiddle.net
      Cc: schwidefsky@de.ibm.com
      Cc: tony.luck@intel.com
      Cc: vgupta@synopsys.com
      Cc: ysato@users.sourceforge.jp
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      726328d9
  6. 14 3月, 2016 1 次提交
    • A
      ipv4: Update parameters for csum_tcpudp_magic to their original types · 01cfbad7
      Alexander Duyck 提交于
      This patch updates all instances of csum_tcpudp_magic and
      csum_tcpudp_nofold to reflect the types that are usually used as the source
      inputs.  For example the protocol field is populated based on nexthdr which
      is actually an unsigned 8 bit value.  The length is usually populated based
      on skb->len which is an unsigned integer.
      
      This addresses an issue in which the IPv6 function csum_ipv6_magic was
      generating a checksum using the full 32b of skb->len while
      csum_tcpudp_magic was only using the lower 16 bits.  As a result we could
      run into issues when attempting to adjust the checksum as there was no
      protocol agnostic way to update it.
      
      With this change the value is still truncated as many architectures use
      "(len + proto) << 8", however this truncation only occurs for values
      greater than 16776960 in length and as such is unlikely to occur as we stop
      the inner headers at ~64K in size.
      
      I did have to make a few minor changes in the arm, mn10300, nios2, and
      score versions of the function in order to support these changes as they
      were either using things such as an OR to combine the protocol and length,
      or were using ntohs to convert the length which would have truncated the
      value.
      
      I also updated a few spots in terms of whitespace and type differences for
      the addresses.  Most of this was just to make sure all of the definitions
      were in sync going forward.
      Signed-off-by: NAlexander Duyck <aduyck@mirantis.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      01cfbad7
  7. 26 2月, 2016 1 次提交
    • T
      net: Facility to report route quality of connected sockets · a87cb3e4
      Tom Herbert 提交于
      This patch add the SO_CNX_ADVICE socket option (setsockopt only). The
      purpose is to allow an application to give feedback to the kernel about
      the quality of the network path for a connected socket. The value
      argument indicates the type of quality report. For this initial patch
      the only supported advice is a value of 1 which indicates "bad path,
      please reroute"-- the action taken by the kernel is to call
      dst_negative_advice which will attempt to choose a different ECMP route,
      reset the TX hash for flow label and UDP source port in encapsulation,
      etc.
      
      This facility should be useful for connected UDP sockets where only the
      application can provide any feedback about path quality. It could also
      be useful for TCP applications that have additional knowledge about the
      path outside of the normal TCP control loop.
      Signed-off-by: NTom Herbert <tom@herbertland.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      a87cb3e4
  8. 05 1月, 2016 1 次提交
  9. 30 12月, 2015 2 次提交
  10. 23 9月, 2015 1 次提交
    • P
      atomic, arch: Audit atomic_{read,set}() · 62e8a325
      Peter Zijlstra 提交于
      This patch makes sure that atomic_{read,set}() are at least
      {READ,WRITE}_ONCE().
      
      We already had the 'requirement' that atomic_read() should use
      ACCESS_ONCE(), and most archs had this, but a few were lacking.
      All are now converted to use READ_ONCE().
      
      And, by a symmetry and general paranoia argument, upgrade atomic_set()
      to use WRITE_ONCE().
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: james.hogan@imgtec.com
      Cc: linux-kernel@vger.kernel.org
      Cc: oleg@redhat.com
      Cc: will.deacon@arm.com
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      62e8a325
  11. 29 7月, 2015 1 次提交
    • L
      arch/*/io.h: Add ioremap_uc() to all architectures · 4c73e892
      Luis R. Rodriguez 提交于
      This adds ioremap_uc() only for architectures that do not
      include asm-generic.h/io.h as that already provides a default
      definition for them for both cases where you have CONFIG_MMU
      and you do not, and because of this, the number of architectures
      this patch address is less than the architectures that the
      ioremap_wt() patch addressed, "arch/*/io.h: Add ioremap_wt() to
      all architectures").
      
      In order to reduce the number of architectures we have to
      modify by adding new architecture IO APIs we'll have to review
      the architectures in this patch, see why they can't add
      asm-generic.h/io.h or issues that would be created by doing
      so and then spread a consistent inclusion of this header
      towards the end of their own header. For instance arch/metag
      includes the asm-generic/io.h *before* the ioremap*()
      definitions, this should be the other way around but only
      once we have guard wrappers for the non-MMU case also for
      asm-generic/io.h.
      Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
      Signed-off-by: NLuis R. Rodriguez <mcgrof@suse.com>
      Cc: Abhilash Kesavan <a.kesavan@samsung.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Chris Metcalf <cmetcalf@ezchip.com>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Fengguang Wu <fengguang.wu@intel.com>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Greg Ungerer <gerg@uclinux.org>
      Cc: Guenter Roeck <linux@roeck-us.net>
      Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
      Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
      Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
      Cc: Kyle McMartin <kyle@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Peter Hurley <peter@hurleysoftware.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Rob Herring <robh@kernel.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Toshi Kani <toshi.kani@hp.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: linux-am33-list@redhat.com
      Cc: linux-arch@vger.kernel.org
      Cc: linux-m68k@lists.linux-m68k.org
      Cc: linux-sh@vger.kernel.org
      Cc: linuxppc-dev@lists.ozlabs.org
      Link: http://lkml.kernel.org/r/20150728181713.GB30479@wotan.suse.deSigned-off-by: NIngo Molnar <mingo@kernel.org>
      4c73e892
  12. 27 7月, 2015 3 次提交
  13. 24 7月, 2015 1 次提交
  14. 18 7月, 2015 1 次提交
  15. 09 7月, 2015 1 次提交
    • C
      Make asm/word-at-a-time.h available on all architectures · a6e2f029
      Chris Metcalf 提交于
      Added the x86 implementation of word-at-a-time to the
      generic version, which previously only supported big-endian.
      
      Omitted the x86-specific load_unaligned_zeropad(), which in
      any case is also not present for the existing BE-only
      implementation of a word-at-a-time, and is only used under
      CONFIG_DCACHE_WORD_ACCESS.
      
      Added as a "generic-y" to the Kbuilds of all architectures
      that didn't previously have it.
      Signed-off-by: NChris Metcalf <cmetcalf@ezchip.com>
      a6e2f029
  16. 25 6月, 2015 1 次提交
    • L
      mm: new mm hook framework · 2ae416b1
      Laurent Dufour 提交于
      CRIU is recreating the process memory layout by remapping the checkpointee
      memory area on top of the current process (criu).  This includes remapping
      the vDSO to the place it has at checkpoint time.
      
      However some architectures like powerpc are keeping a reference to the
      vDSO base address to build the signal return stack frame by calling the
      vDSO sigreturn service.  So once the vDSO has been moved, this reference
      is no more valid and the signal frame built later are not usable.
      
      This patch serie is introducing a new mm hook framework, and a new
      arch_remap hook which is called when mremap is done and the mm lock still
      hold.  The next patch is adding the vDSO remap and unmap tracking to the
      powerpc architecture.
      
      This patch (of 3):
      
      This patch introduces a new set of header file to manage mm hooks:
      - per architecture empty header file (arch/x/include/asm/mm-arch-hooks.h)
      - a generic header (include/linux/mm-arch-hooks.h)
      
      The architecture which need to overwrite a hook as to redefine it in its
      header file, while architecture which doesn't need have nothing to do.
      
      The default hooks are defined in the generic header and are used in the
      case the architecture is not defining it.
      
      In a next step, mm hooks defined in include/asm-generic/mm_hooks.h should
      be moved here.
      Signed-off-by: NLaurent Dufour <ldufour@linux.vnet.ibm.com>
      Suggested-by: NAndrew Morton <akpm@linux-foundation.org>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: Hugh Dickins <hughd@google.com>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Mel Gorman <mgorman@suse.de>
      Cc: Pavel Emelyanov <xemul@parallels.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Ingo Molnar <mingo@kernel.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      2ae416b1
  17. 07 6月, 2015 1 次提交
    • T
      arch/*/io.h: Add ioremap_wt() to all architectures · 556269c1
      Toshi Kani 提交于
      Add ioremap_wt() to all arch-specific asm/io.h headers which
      define ioremap_wc() locally. These headers do not include
      <asm-generic/iomap.h>. Some of them include <asm-generic/io.h>,
      but ioremap_wt() is defined for consistency since they define
      all ioremap_xxx locally.
      
      In all architectures without Write-Through support, ioremap_wt()
      is defined indentical to ioremap_nocache().
      
      frv and m68k already have ioremap_writethrough(). On those we
      add ioremap_wt() indetical to ioremap_writethrough() and defines
      ARCH_HAS_IOREMAP_WT in both architectures.
      
      The ioremap_wt() interface is exported to drivers.
      Signed-off-by: NToshi Kani <toshi.kani@hp.com>
      Signed-off-by: NBorislav Petkov <bp@suse.de>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Elliott@hp.com
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Luis R. Rodriguez <mcgrof@suse.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: arnd@arndb.de
      Cc: hch@lst.de
      Cc: hmh@hmh.eng.br
      Cc: jgross@suse.com
      Cc: konrad.wilk@oracle.com
      Cc: linux-mm <linux-mm@kvack.org>
      Cc: linux-nvdimm@lists.01.org
      Cc: stefan.bader@canonical.com
      Cc: yigal@plexistor.com
      Link: http://lkml.kernel.org/r/1433436928-31903-9-git-send-email-bp@alien8.deSigned-off-by: NIngo Molnar <mingo@kernel.org>
      556269c1
  18. 19 5月, 2015 2 次提交
  19. 13 5月, 2015 1 次提交
  20. 13 4月, 2015 2 次提交
  21. 17 3月, 2015 1 次提交
  22. 01 3月, 2015 1 次提交
    • K
      mm: add missing __PAGETABLE_{PUD,PMD}_FOLDED defines · c07af4f1
      Kirill A. Shutemov 提交于
      Core mm expects __PAGETABLE_{PUD,PMD}_FOLDED to be defined if these page
      table levels folded.  Usually, these defines are provided by
      <asm-generic/pgtable-nopmd.h> and <asm-generic/pgtable-nopud.h>.
      
      But some architectures fold page table levels in a custom way.  They
      need to define these macros themself.  This patch adds missing defines.
      
      The patch fixes mm->nr_pmds underflow and eliminates dead __pmd_alloc()
      and __pud_alloc() on architectures without these page table levels.
      Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Helge Deller <deller@gmx.de>
      Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
      Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      c07af4f1
  23. 13 2月, 2015 1 次提交
    • A
      all arches, signal: move restart_block to struct task_struct · f56141e3
      Andy Lutomirski 提交于
      If an attacker can cause a controlled kernel stack overflow, overwriting
      the restart block is a very juicy exploit target.  This is because the
      restart_block is held in the same memory allocation as the kernel stack.
      
      Moving the restart block to struct task_struct prevents this exploit by
      making the restart_block harder to locate.
      
      Note that there are other fields in thread_info that are also easy
      targets, at least on some architectures.
      
      It's also a decent simplification, since the restart code is more or less
      identical on all architectures.
      
      [james.hogan@imgtec.com: metag: align thread_info::supervisor_stack]
      Signed-off-by: NAndy Lutomirski <luto@amacapital.net>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: David Miller <davem@davemloft.net>
      Acked-by: NRichard Weinberger <richard@nod.at>
      Cc: Richard Henderson <rth@twiddle.net>
      Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
      Cc: Matt Turner <mattst88@gmail.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Russell King <rmk@arm.linux.org.uk>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
      Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
      Cc: Steven Miao <realmz6@gmail.com>
      Cc: Mark Salter <msalter@redhat.com>
      Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
      Cc: Mikael Starvik <starvik@axis.com>
      Cc: Jesper Nilsson <jesper.nilsson@axis.com>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Richard Kuo <rkuo@codeaurora.org>
      Cc: "Luck, Tony" <tony.luck@intel.com>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Cc: Michal Simek <monstr@monstr.eu>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Jonas Bonn <jonas@southpole.se>
      Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
      Cc: Helge Deller <deller@gmx.de>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
      Tested-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Chen Liqin <liqin.linux@gmail.com>
      Cc: Lennox Wu <lennox.wu@gmail.com>
      Cc: Chris Metcalf <cmetcalf@ezchip.com>
      Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
      Cc: Chris Zankel <chris@zankel.net>
      Cc: Max Filippov <jcmvbkbc@gmail.com>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Guenter Roeck <linux@roeck-us.net>
      Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      f56141e3
  24. 12 2月, 2015 1 次提交
  25. 11 2月, 2015 1 次提交
  26. 13 1月, 2015 2 次提交
  27. 11 12月, 2014 1 次提交
  28. 06 12月, 2014 1 次提交
    • A
      net: sock: allow eBPF programs to be attached to sockets · 89aa0758
      Alexei Starovoitov 提交于
      introduce new setsockopt() command:
      
      setsockopt(sock, SOL_SOCKET, SO_ATTACH_BPF, &prog_fd, sizeof(prog_fd))
      
      where prog_fd was received from syscall bpf(BPF_PROG_LOAD, attr, ...)
      and attr->prog_type == BPF_PROG_TYPE_SOCKET_FILTER
      
      setsockopt() calls bpf_prog_get() which increments refcnt of the program,
      so it doesn't get unloaded while socket is using the program.
      
      The same eBPF program can be attached to multiple sockets.
      
      User task exit automatically closes socket which calls sk_filter_uncharge()
      which decrements refcnt of eBPF program
      Signed-off-by: NAlexei Starovoitov <ast@plumgrid.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      89aa0758
  29. 12 11月, 2014 1 次提交
    • E
      net: introduce SO_INCOMING_CPU · 2c8c56e1
      Eric Dumazet 提交于
      Alternative to RPS/RFS is to use hardware support for multiple
      queues.
      
      Then split a set of million of sockets into worker threads, each
      one using epoll() to manage events on its own socket pool.
      
      Ideally, we want one thread per RX/TX queue/cpu, but we have no way to
      know after accept() or connect() on which queue/cpu a socket is managed.
      
      We normally use one cpu per RX queue (IRQ smp_affinity being properly
      set), so remembering on socket structure which cpu delivered last packet
      is enough to solve the problem.
      
      After accept(), connect(), or even file descriptor passing around
      processes, applications can use :
      
       int cpu;
       socklen_t len = sizeof(cpu);
      
       getsockopt(fd, SOL_SOCKET, SO_INCOMING_CPU, &cpu, &len);
      
      And use this information to put the socket into the right silo
      for optimal performance, as all networking stack should run
      on the appropriate cpu, without need to send IPI (RPS/RFS).
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      2c8c56e1
  30. 21 10月, 2014 1 次提交
    • W
      m32r: io: implement dummy relaxed accessor macros for writes · cb147c0f
      Will Deacon 提交于
      write{b,w,l}_relaxed are implemented by some architectures in order to
      permit memory-mapped I/O accesses with weaker barrier semantics than the
      non-relaxed variants.
      
      This patch adds dummy macros for the write accessors to m32r, in the
      same vein as the dummy definitions for the relaxed read accessors.
      
      Cc: Hirokazu Takata <takata@linux-m32r.org>
      Signed-off-by: NWill Deacon <will.deacon@arm.com>
      cb147c0f
  31. 10 10月, 2014 1 次提交
  32. 03 10月, 2014 1 次提交