Skip to content

K
Kernel

openeuler / Kernel
大约 1 年 前同步成功

通知 6
Star 0
Fork 0
K
Kernel
切换分支/标签
  1. 14 11月, 2005 4 次提交
  3. 10 11月, 2005 1 次提交
  5. 09 11月, 2005 1 次提交
  7. 07 11月, 2005 14 次提交
  9. 02 11月, 2005 1 次提交
  11. 31 10月, 2005 5 次提交
  13. 30 10月, 2005 5 次提交
    • H
      [PATCH] mm: split page table lock · 4c21e2f2
      由 Hugh Dickins 提交于 
      Christoph Lameter demonstrated very poor scalability on the SGI 512-way, with
a many-threaded application which concurrently initializes different parts of
a large anonymous area.

This patch corrects that, by using a separate spinlock per page table page, to
guard the page table entries in that page, instead of using the mm's single
page_table_lock.  (But even then, page_table_lock is still used to guard page
table allocation, and anon_vma allocation.)

In this implementation, the spinlock is tucked inside the struct page of the
page table page: with a BUILD_BUG_ON in case it overflows - which it would in
the case of 32-bit PA-RISC with spinlock debugging enabled.

Splitting the lock is not quite for free: another cacheline access.  Ideally,
I suppose we would use split ptlock only for multi-threaded processes on
multi-cpu machines; but deciding that dynamically would have its own costs.
So for now enable it by config, at some number of cpus - since the Kconfig
language doesn't support inequalities, let preprocessor compare that with
NR_CPUS.  But I don't think it's worth being user-configurable: for good
testing of both split and unsplit configs, split now at 4 cpus, and perhaps
change that to 8 later.

There is a benefit even for singly threaded processes: kswapd can be attacking
one part of the mm while another part is busy faulting.
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      4c21e2f2
    • H
      [PATCH] mm: uml kill unused · b38c6845
      由 Hugh Dickins 提交于 
      In worrying over the various pte operations in different architectures, I came
across some unused functions in UML: remove mprotect_kernel_vm,
protect_vm_page and addr_pte.
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      b38c6845
    • H
      [PATCH] mm: uml pte atomicity · 8f5cd76c
      由 Hugh Dickins 提交于 
      There's usually a good reason when a pte is examined without the lock; but it
makes me nervous when the pointer is dereferenced more than once.
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      8f5cd76c
    • H
      [PATCH] mm: arches skip ptlock · b462705a
      由 Hugh Dickins 提交于 
      Convert those few architectures which are calling pud_alloc, pmd_alloc,
pte_alloc_map on a user mm, not to take the page_table_lock first, nor drop it
after.  Each of these can continue to use pte_alloc_map, no need to change
over to pte_alloc_map_lock, they're neither racy nor swappable.

In the sparc64 io_remap_pfn_range, flush_tlb_range then falls outside of the
page_table_lock: that's okay, on sparc64 it's like flush_tlb_mm, and that has
always been called from outside of page_table_lock in dup_mmap.
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      b462705a
    • R
      Create platform_device.h to contain all the platform device details. · d052d1be
      由 Russell King 提交于 
      Convert everyone who uses platform_bus_type to include
linux/platform_device.h.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
      d052d1be
  15. 28 10月, 2005 1 次提交
  17. 24 10月, 2005 1 次提交
  19. 20 10月, 2005 1 次提交
  21. 12 10月, 2005 2 次提交
  23. 10 10月, 2005 4 次提交