Skip to content

L
linux
Switch branch/tag
  1. 17 Mar, 2009 3 commits
  3. 15 Mar, 2009 6 commits
  5. 14 Mar, 2009 3 commits
    • Jeremy Fitzhardinge's avatar
      x86: add brk allocation for very, very early allocations · 93dbda7c
      Jeremy Fitzhardinge authored 
      Impact: new interface

Add a brk()-like allocator which effectively extends the bss in order
to allow very early code to do dynamic allocations.  This is better than
using statically allocated arrays for data in subsystems which may never
get used.

The space for brk allocations is in the bss ELF segment, so that the
space is mapped properly by the code which maps the kernel, and so
that bootloaders keep the space free rather than putting a ramdisk or
something into it.

The bss itself, delimited by __bss_stop, ends before the brk area
(__brk_base to __brk_limit).  The kernel text, data and bss is reserved
up to __bss_stop.

Any brk-allocated data is reserved separately just before the kernel
pagetable is built, as that code allocates from unreserved spaces
in the e820 map, potentially allocating from any unused brk memory.
Ultimately any unused memory in the brk area is used in the general
kernel memory pool.

Initially the brk space is set to 1MB, which is probably much larger
than any user needs (the largest current user is i386 head_32.S's code
to build the pagetables to map the kernel, which can get fairly large
with a big kernel image and no PSE support).  So long as the system
has sufficient memory for the bootloader to reserve the kernel+1MB brk,
there are no bad effects resulting from an over-large brk.
Signed-off-by: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
      93dbda7c
    • Jeremy Fitzhardinge's avatar
      x86: make section delimiter symbols part of their section · b9719a4d
      Jeremy Fitzhardinge authored 
      Impact: cleanup

Move the symbols delimiting a section part of the section
(section relative) rather than absolute.  This avoids any
unexpected gaps between the section-start symbol and the first
data in the section, which could be caused by implicit
alignment of the section data.  It also makes the general
form of vmlinux_64.lds.S consistent with vmlinux_32.lds.S.
Signed-off-by: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
      b9719a4d
    • Ingo Molnar's avatar
      Merge branch 'core/percpu' into x86/core · c550033c
      Ingo Molnar authored
      c550033c
  7. 13 Mar, 2009 1 commit
    • Li Zefan's avatar
      cpuacct: reduce one NULL check in fast-path · 7a46c594
      Li Zefan authored 
      Impact: micro-optimization

In cpuacct_charge(), task_ca() will never return NULL, so change
for(...) to do { } while(...) to save one NULL check.
Signed-off-by: default avatarLi Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Menage <menage@google.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Bharata B Rao <bharata@linux.vnet.ibm.com>
LKML-Reference: <49B863F5.2060400@cn.fujitsu.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      7a46c594
  9. 12 Mar, 2009 1 commit
  11. 11 Mar, 2009 26 commits
GitLab Nexedi Edition | About GitLab | About Nexedi | 沪ICP备2021021310号-2 | 沪ICP备2021021310号-7