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  1. 20 3月, 2009 1 次提交
  3. 17 3月, 2009 2 次提交
    • P
      sh: Flush only the needed range when unmapping a VMA. · c2035184
      由 Paul Mundt 提交于 
      This follows the ARM change from Aaro Koskinen:

	When unmapping N pages (e.g. shared memory) the amount of TLB
	flushes done can be (N*PAGE_SIZE/ZAP_BLOCK_SIZE)*N although it
	should be N at maximum. With PREEMPT kernel ZAP_BLOCK_SIZE is 8
	pages, so there is a noticeable performance penalty when
	unmapping a large VMA and the system is spending its time in
	flush_tlb_range().

	The problem is that tlb_end_vma() is always flushing the full VMA
	range. The subrange that needs to be flushed can be calculated by
	tlb_remove_tlb_entry(). This approach was suggested by Hugh
	Dickins, and is also used by other arches.

	The speed increase is roughly 3x for 8M mappings and for larger
	mappings even more.

Bits and peices are taken from the ARM patch as well as the existing
arch/um implementation that is quite similar.

The end result is a significant reduction in both partial and full TLB
flushes initiated through flush_tlb_range().

At the same time, the nommu implementation was broken, had a superfluous
cache flush, and subsequently would have triggered a BUG_ON() if a
code-path had triggered it. Tidy this up for correctness and provide a
nopped-out implementation there.

More background on the initial discussion can be found at:

	http://marc.info/?t=123609820900002&r=1&w=2
	http://marc.info/?t=123660375800003&r=1&w=2Signed-off-by: NPaul Mundt <lethal@linux-sh.org>
      c2035184
    • P
      sh: Support for extended ASIDs on PTEAEX-capable SH-X3 cores. · 8263a67e
      由 Paul Mundt 提交于 
      This adds support for extended ASIDs (up to 16-bits) on newer SH-X3 cores
that implement the PTAEX register and respective functionality. Presently
only the 65nm SH7786 (90nm only supports legacy 8-bit ASIDs).

The main change is in how the PTE is written out when loading the entry
in to the TLB, as well as in how the TLB entry is selectively flushed.

While SH-X2 extended mode splits out the memory-mapped U and I-TLB data
arrays for extra bits, extended ASID mode splits out the address arrays.
While we don't use the memory-mapped data array access, the address
array accesses are necessary for selective TLB flushes, so these are
implemented newly and replace the generic SH-4 implementation.

With this, TLB flushes in switch_mm() are almost non-existent on newer
parts.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>
      8263a67e
  5. 16 3月, 2009 2 次提交
  7. 11 3月, 2009 1 次提交
  9. 10 3月, 2009 3 次提交
  11. 03 3月, 2009 1 次提交
  13. 27 2月, 2009 3 次提交
  15. 16 2月, 2009 1 次提交
    • P
      net: new user space API for time stamping of incoming and outgoing packets · cb9eff09
      由 Patrick Ohly 提交于 
      User space can request hardware and/or software time stamping.
Reporting of the result(s) via a new control message is enabled
separately for each field in the message because some of the
fields may require additional computation and thus cause overhead.
User space can tell the different kinds of time stamps apart
and choose what suits its needs.

When a TX timestamp operation is requested, the TX skb will be cloned
and the clone will be time stamped (in hardware or software) and added
to the socket error queue of the skb, if the skb has a socket
associated with it.

The actual TX timestamp will reach userspace as a RX timestamp on the
cloned packet. If timestamping is requested and no timestamping is
done in the device driver (potentially this may use hardware
timestamping), it will be done in software after the device's
start_hard_xmit routine.
Signed-off-by: NPatrick Ohly <patrick.ohly@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      cb9eff09
  17. 29 1月, 2009 6 次提交
  19. 27 1月, 2009 3 次提交
  21. 21 1月, 2009 1 次提交
  23. 15 1月, 2009 1 次提交
  25. 14 1月, 2009 1 次提交
  27. 08 1月, 2009 1 次提交
    • D
      NOMMU: Make VMAs per MM as for MMU-mode linux · 8feae131
      由 David Howells 提交于 
      Make VMAs per mm_struct as for MMU-mode linux.  This solves two problems:

 (1) In SYSV SHM where nattch for a segment does not reflect the number of
     shmat's (and forks) done.

 (2) In mmap() where the VMA's vm_mm is set to point to the parent mm by an
     exec'ing process when VM_EXECUTABLE is specified, regardless of the fact
     that a VMA might be shared and already have its vm_mm assigned to another
     process or a dead process.

A new struct (vm_region) is introduced to track a mapped region and to remember
the circumstances under which it may be shared and the vm_list_struct structure
is discarded as it's no longer required.

This patch makes the following additional changes:

 (1) Regions are now allocated with alloc_pages() rather than kmalloc() and
     with no recourse to __GFP_COMP, so the pages are not composite.  Instead,
     each page has a reference on it held by the region.  Anything else that is
     interested in such a page will have to get a reference on it to retain it.
     When the pages are released due to unmapping, each page is passed to
     put_page() and will be freed when the page usage count reaches zero.

 (2) Excess pages are trimmed after an allocation as the allocation must be
     made as a power-of-2 quantity of pages.

 (3) VMAs are added to the parent MM's R/B tree and mmap lists.  As an MM may
     end up with overlapping VMAs within the tree, the VMA struct address is
     appended to the sort key.

 (4) Non-anonymous VMAs are now added to the backing inode's prio list.

 (5) Holes may be punched in anonymous VMAs with munmap(), releasing parts of
     the backing region.  The VMA and region structs will be split if
     necessary.

 (6) sys_shmdt() only releases one attachment to a SYSV IPC shared memory
     segment instead of all the attachments at that addresss.  Multiple
     shmat()'s return the same address under NOMMU-mode instead of different
     virtual addresses as under MMU-mode.

 (7) Core dumping for ELF-FDPIC requires fewer exceptions for NOMMU-mode.

 (8) /proc/maps is now the global list of mapped regions, and may list bits
     that aren't actually mapped anywhere.

 (9) /proc/meminfo gains a line (tagged "MmapCopy") that indicates the amount
     of RAM currently allocated by mmap to hold mappable regions that can't be
     mapped directly.  These are copies of the backing device or file if not
     anonymous.

These changes make NOMMU mode more similar to MMU mode.  The downside is that
NOMMU mode requires some extra memory to track things over NOMMU without this
patch (VMAs are no longer shared, and there are now region structs).
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Tested-by: NMike Frysinger <vapier.adi@gmail.com>
Acked-by: NPaul Mundt <lethal@linux-sh.org>
      8feae131
  29. 07 1月, 2009 2 次提交
  31. 26 12月, 2008 1 次提交
  33. 25 12月, 2008 1 次提交
    • M
      [S390] arch_setup_additional_pages arguments · fc5243d9
      由 Martin Schwidefsky 提交于 
      arch_setup_additional_pages currently gets two arguments, the binary
format descripton and an indication if the process uses an executable
stack or not. The second argument is not used by anybody, it could
be removed without replacement.

What actually does make sense is to pass an indication if the process
uses the elf interpreter or not. The glibc code will not use anything
from the vdso if the process does not use the dynamic linker, so for
statically linked binaries the architecture backend can choose not
to map the vdso.
Acked-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      fc5243d9
  35. 22 12月, 2008 9 次提交