1. 23 6月, 2009 1 次提交
    • P
      x86: Move init_gbpages() to setup_arch() · 854c879f
      Pekka J Enberg 提交于
      The init_gbpages() function is conditionally called from
      init_memory_mapping() function. There are two call-sites where
      this 'after_bootmem' condition can be true: setup_arch() and
      mem_init() via pci_iommu_alloc().
      
      Therefore, it's safe to move the call to init_gbpages() to
      setup_arch() as it's always called before mem_init().
      
      This removes an after_bootmem use - paving the way to remove
      all uses of that state variable.
      Signed-off-by: NPekka Enberg <penberg@cs.helsinki.fi>
      Acked-by: NYinghai Lu <yinghai@kernel.org>
      LKML-Reference: <Pine.LNX.4.64.0906221731210.19474@melkki.cs.Helsinki.FI>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      854c879f
  2. 22 6月, 2009 8 次提交
    • T
      x86: ensure percpu lpage doesn't consume too much vmalloc space · 0017c869
      Tejun Heo 提交于
      On extreme configuration (e.g. 32bit 32-way NUMA machine), lpage
      percpu first chunk allocator can consume too much of vmalloc space.
      Make it fall back to 4k allocator if the consumption goes over 20%.
      
      [ Impact: add sanity check for lpage percpu first chunk allocator ]
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Reported-by: NJan Beulich <JBeulich@novell.com>
      Cc: Andi Kleen <andi@firstfloor.org>
      Cc: Ingo Molnar <mingo@elte.hu>
      0017c869
    • T
      x86: implement percpu_alloc kernel parameter · fa8a7094
      Tejun Heo 提交于
      According to Andi, it isn't clear whether lpage allocator is worth the
      trouble as there are many processors where PMD TLB is far scarcer than
      PTE TLB.  The advantage or disadvantage probably depends on the actual
      size of percpu area and specific processor.  As performance
      degradation due to TLB pressure tends to be highly workload specific
      and subtle, it is difficult to decide which way to go without more
      data.
      
      This patch implements percpu_alloc kernel parameter to allow selecting
      which first chunk allocator to use to ease debugging and testing.
      
      While at it, make sure all the failure paths report why something
      failed to help determining why certain allocator isn't working.  Also,
      kill the "Great future plan" comment which had already been realized
      quite some time ago.
      
      [ Impact: allow explicit percpu first chunk allocator selection ]
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Reported-by: NJan Beulich <JBeulich@novell.com>
      Cc: Andi Kleen <andi@firstfloor.org>
      Cc: Ingo Molnar <mingo@elte.hu>
      fa8a7094
    • T
      x86: fix pageattr handling for lpage percpu allocator and re-enable it · e59a1bb2
      Tejun Heo 提交于
      lpage allocator aliases a PMD page for each cpu and returns whatever
      is unused to the page allocator.  When the pageattr of the recycled
      pages are changed, this makes the two aliases point to the overlapping
      regions with different attributes which isn't allowed and known to
      cause subtle data corruption in certain cases.
      
      This can be handled in simliar manner to the x86_64 highmap alias.
      pageattr code should detect if the target pages have PMD alias and
      split the PMD alias and synchronize the attributes.
      
      pcpur allocator is updated to keep the allocated PMD pages map sorted
      in ascending address order and provide pcpu_lpage_remapped() function
      which binary searches the array to determine whether the given address
      is aliased and if so to which address.  pageattr is updated to use
      pcpu_lpage_remapped() to detect the PMD alias and split it up as
      necessary from cpa_process_alias().
      
      Jan Beulich spotted the original problem and incorrect usage of vaddr
      instead of laddr for lookup.
      
      With this, lpage percpu allocator should work correctly.  Re-enable
      it.
      
      [ Impact: fix subtle lpage pageattr bug and re-enable lpage ]
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Reported-by: NJan Beulich <JBeulich@novell.com>
      Cc: Andi Kleen <andi@firstfloor.org>
      Cc: Ingo Molnar <mingo@elte.hu>
      e59a1bb2
    • T
      x86: reorganize cpa_process_alias() · 992f4c1c
      Tejun Heo 提交于
      Reorganize cpa_process_alias() so that new alias condition can be
      added easily.
      
      Jan Beulich spotted problem in the original cleanup thread which
      incorrectly assumed the two existing conditions were mutially
      exclusive.
      
      [ Impact: code reorganization ]
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Cc: Jan Beulich <JBeulich@novell.com>
      Cc: Andi Kleen <andi@firstfloor.org>
      Cc: Ingo Molnar <mingo@elte.hu>
      992f4c1c
    • T
      x86: prepare setup_pcpu_lpage() for pageattr fix · 0ff2587f
      Tejun Heo 提交于
      Make the following changes in preparation of coming pageattr updates.
      
      * Define and use array of struct pcpul_ent instead of array of
        pointers.  The only difference is ->cpu field which is set but
        unused yet.
      
      * Rename variables according to the above change.
      
      * Rename local variable vm to pcpul_vm and move it out of the
        function.
      
      [ Impact: no functional difference ]
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Cc: Jan Beulich <JBeulich@novell.com>
      Cc: Andi Kleen <andi@firstfloor.org>
      Cc: Ingo Molnar <mingo@elte.hu>
      0ff2587f
    • T
      x86: rename remap percpu first chunk allocator to lpage · 97c9bf06
      Tejun Heo 提交于
      The "remap" allocator remaps large pages to build the first chunk;
      however, the name isn't very good because 4k allocator remaps too and
      the whole point of the remap allocator is using large page mapping.
      The allocator will be generalized and exported outside of x86, rename
      it to lpage before that happens.
      
      percpu_alloc kernel parameter is updated to accept both "remap" and
      "lpage" for lpage allocator.
      
      [ Impact: code cleanup, kernel parameter argument updated ]
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Cc: Ingo Molnar <mingo@elte.hu>
      97c9bf06
    • T
      x86: fix duplicate free in setup_pcpu_remap() failure path · c5806df9
      Tejun Heo 提交于
      In the failure path, setup_pcpu_remap() tries to free the area which
      has already been freed to make holes in the large page.  Fix it.
      
      [ Impact: fix duplicate free in failure path ]
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Cc: Ingo Molnar <mingo@elte.hu>
      c5806df9
    • L
      Move FAULT_FLAG_xyz into handle_mm_fault() callers · d06063cc
      Linus Torvalds 提交于
      This allows the callers to now pass down the full set of FAULT_FLAG_xyz
      flags to handle_mm_fault().  All callers have been (mechanically)
      converted to the new calling convention, there's almost certainly room
      for architectures to clean up their code and then add FAULT_FLAG_RETRY
      when that support is added.
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      d06063cc
  3. 21 6月, 2009 3 次提交
    • A
      x86: Set cpu_llc_id on AMD CPUs · 99bd0c0f
      Andreas Herrmann 提交于
      This counts when building sched domains in case NUMA information
      is not available.
      
      ( See cpu_coregroup_mask() which uses llc_shared_map which in turn is
        created based on cpu_llc_id. )
      
      Currently Linux builds domains as follows:
      (example from a dual socket quad-core system)
      
       CPU0 attaching sched-domain:
        domain 0: span 0-7 level CPU
         groups: 0 1 2 3 4 5 6 7
      
        ...
      
       CPU7 attaching sched-domain:
        domain 0: span 0-7 level CPU
         groups: 7 0 1 2 3 4 5 6
      
      Ever since that is borked for multi-core AMD CPU systems.
      This patch fixes that and now we get a proper:
      
       CPU0 attaching sched-domain:
        domain 0: span 0-3 level MC
         groups: 0 1 2 3
         domain 1: span 0-7 level CPU
          groups: 0-3 4-7
      
        ...
      
       CPU7 attaching sched-domain:
        domain 0: span 4-7 level MC
         groups: 7 4 5 6
         domain 1: span 0-7 level CPU
          groups: 4-7 0-3
      
      This allows scheduler to assign tasks to cores on different sockets
      (i.e. that don't share last level cache) for performance reasons.
      Signed-off-by: NAndreas Herrmann <andreas.herrmann3@amd.com>
      LKML-Reference: <20090619085909.GJ5218@alberich.amd.com>
      Cc: <stable@kernel.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      99bd0c0f
    • L
      x86, 64-bit: Clean up user address masking · 9063c61f
      Linus Torvalds 提交于
      The discussion about using "access_ok()" in get_user_pages_fast() (see
      commit 7f818906: "x86: don't use
      'access_ok()' as a range check in get_user_pages_fast()" for details and
      end result), made us notice that x86-64 was really being very sloppy
      about virtual address checking.
      
      So be way more careful and straightforward about masking x86-64 virtual
      addresses:
      
       - All the VIRTUAL_MASK* variants now cover half of the address
         space, it's not like we can use the full mask on a signed
         integer, and the larger mask just invites mistakes when
         applying it to either half of the 48-bit address space.
      
       - /proc/kcore's kc_offset_to_vaddr() becomes a lot more
         obvious when it transforms a file offset into a
         (kernel-half) virtual address.
      
       - Unify/simplify the 32-bit and 64-bit USER_DS definition to
         be based on TASK_SIZE_MAX.
      
      This cleanup and more careful/obvious user virtual address checking also
      uncovered a buglet in the x86-64 implementation of strnlen_user(): it
      would do an "access_ok()" check on the whole potential area, even if the
      string itself was much shorter, and thus return an error even for valid
      strings. Our sloppy checking had hidden this.
      
      So this fixes 'strnlen_user()' to do this properly, the same way we
      already handled user strings in 'strncpy_from_user()'.  Namely by just
      checking the first byte, and then relying on fault handling for the
      rest.  That always works, since we impose a guard page that cannot be
      mapped at the end of the user space address space (and even if we
      didn't, we'd have the address space hole).
      Acked-by: NIngo Molnar <mingo@elte.hu>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Nick Piggin <npiggin@suse.de>
      Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      9063c61f
    • L
      x86: don't use 'access_ok()' as a range check in get_user_pages_fast() · 7f818906
      Linus Torvalds 提交于
      It's really not right to use 'access_ok()', since that is meant for the
      normal "get_user()" and "copy_from/to_user()" accesses, which are done
      through the TLB, rather than through the page tables.
      
      Why? access_ok() does both too few, and too many checks.  Too many,
      because it is meant for regular kernel accesses that will not honor the
      'user' bit in the page tables, and because it honors the USER_DS vs
      KERNEL_DS distinction that we shouldn't care about in GUP.  And too few,
      because it doesn't do the 'canonical' check on the address on x86-64,
      since the TLB will do that for us.
      
      So instead of using a function that isn't meant for this, and does
      something else and much more complicated, just do the real rules: we
      don't want the range to overflow, and on x86-64, we want it to be a
      canonical low address (on 32-bit, all addresses are canonical).
      Acked-by: NIngo Molnar <mingo@elte.hu>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      7f818906
  4. 20 6月, 2009 3 次提交
  5. 19 6月, 2009 25 次提交