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  1. 27 8月, 2014 2 次提交
    • T
      Revert "powerpc: Replace __get_cpu_var uses" · 23f66e2d
      由 Tejun Heo 提交于 
      This reverts commit 5828f666 due to
build failure after merging with pending powerpc changes.

Link: http://lkml.kernel.org/g/20140827142243.6277eaff@canb.auug.org.auSigned-off-by: NTejun Heo <tj@kernel.org>
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      23f66e2d
    • C
      powerpc: Replace __get_cpu_var uses · 5828f666
      由 Christoph Lameter 提交于 
      __get_cpu_var() is used for multiple purposes in the kernel source. One of
them is address calculation via the form &__get_cpu_var(x).  This calculates
the address for the instance of the percpu variable of the current processor
based on an offset.

Other use cases are for storing and retrieving data from the current
processors percpu area.  __get_cpu_var() can be used as an lvalue when
writing data or on the right side of an assignment.

__get_cpu_var() is defined as :

#define __get_cpu_var(var) (*this_cpu_ptr(&(var)))

__get_cpu_var() always only does an address determination. However, store
and retrieve operations could use a segment prefix (or global register on
other platforms) to avoid the address calculation.

this_cpu_write() and this_cpu_read() can directly take an offset into a
percpu area and use optimized assembly code to read and write per cpu
variables.

This patch converts __get_cpu_var into either an explicit address
calculation using this_cpu_ptr() or into a use of this_cpu operations that
use the offset.  Thereby address calculations are avoided and less registers
are used when code is generated.

At the end of the patch set all uses of __get_cpu_var have been removed so
the macro is removed too.

The patch set includes passes over all arches as well. Once these operations
are used throughout then specialized macros can be defined in non -x86
arches as well in order to optimize per cpu access by f.e.  using a global
register that may be set to the per cpu base.

Transformations done to __get_cpu_var()

1. Determine the address of the percpu instance of the current processor.

	DEFINE_PER_CPU(int, y);
	int *x = &__get_cpu_var(y);

    Converts to

	int *x = this_cpu_ptr(&y);

2. Same as #1 but this time an array structure is involved.

	DEFINE_PER_CPU(int, y[20]);
	int *x = __get_cpu_var(y);

    Converts to

	int *x = this_cpu_ptr(y);

3. Retrieve the content of the current processors instance of a per cpu
variable.

	DEFINE_PER_CPU(int, y);
	int x = __get_cpu_var(y)

   Converts to

	int x = __this_cpu_read(y);

4. Retrieve the content of a percpu struct

	DEFINE_PER_CPU(struct mystruct, y);
	struct mystruct x = __get_cpu_var(y);

   Converts to

	memcpy(&x, this_cpu_ptr(&y), sizeof(x));

5. Assignment to a per cpu variable

	DEFINE_PER_CPU(int, y)
	__get_cpu_var(y) = x;

   Converts to

	__this_cpu_write(y, x);

6. Increment/Decrement etc of a per cpu variable

	DEFINE_PER_CPU(int, y);
	__get_cpu_var(y)++

   Converts to

	__this_cpu_inc(y)

tj: Folded a fix patch.
    http://lkml.kernel.org/g/alpine.DEB.2.11.1408172143020.9652@gentwo.org

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NTejun Heo <tj@kernel.org>
      5828f666
  3. 09 1月, 2014 1 次提交
  5. 18 10月, 2013 1 次提交
  7. 17 10月, 2013 1 次提交
  9. 27 4月, 2013 2 次提交
  11. 13 2月, 2013 1 次提交
  13. 08 4月, 2012 5 次提交
  15. 05 3月, 2012 4 次提交
    • A
      KVM: PPC: E500: Fail init when not on e500v2 · 9cf7c0e4
      由 Alexander Graf 提交于 
      When enabling the current KVM code on e500mc, I get the following oops:

    Oops: Exception in kernel mode, sig: 4 [#1]
    SMP NR_CPUS=8 P2041 RDB
    Modules linked in:
    NIP: c067df4c LR: c067df44 CTR: 00000000
    REGS: ee055ed0 TRAP: 0700   Not tainted  (3.2.0-10391-g36c5afe)
    MSR: 00029002 <CE,EE,ME>  CR: 24042022  XER: 00000000
    TASK = ee0429b0[1] 'swapper/0' THREAD: ee054000 CPU: 2
    GPR00: c067df44 ee055f80 ee0429b0 00000000 00000058 0000003f ee211600 60c6b864
    GPR08: 7cc903a6 0000002c 00000000 00000001 44042082 2d180088 00000000 00000000
    GPR16: c0000a00 00000014 3fffffff 03fe9000 00000015 7ff3be68 c06e0000 00000000
    GPR24: 00000000 00000000 00001720 c067df1c c06e0000 00000000 ee054000 c06ab51c
    NIP [c067df4c] kvmppc_e500_init+0x30/0xf8
    LR [c067df44] kvmppc_e500_init+0x28/0xf8
    Call Trace:
    [ee055f80] [c067df44] kvmppc_e500_init+0x28/0xf8 (unreliable)
    [ee055fb0] [c0001d30] do_one_initcall+0x50/0x1f0
    [ee055fe0] [c06721dc] kernel_init+0xa4/0x14c
    [ee055ff0] [c000e910] kernel_thread+0x4c/0x68
    Instruction dump:
    9421ffd0 7c0802a6 93410018 9361001c 90010034 93810020 93a10024 93c10028
    93e1002c 4bfffe7d 2c030000 408200a4 <7c1082a6> 90010008 7c1182a6 9001000c
    ---[ end trace b8ef4903fcbf9dd3 ]---

Since it doesn't make sense to run the init function on any non-supported
platform, we can just call our "is this platform supported?" function and
bail out of init() if it's not.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>
      9cf7c0e4
    • S
      KVM: PPC: Paravirtualize SPRG4-7, ESR, PIR, MASn · b5904972
      由 Scott Wood 提交于 
      This allows additional registers to be accessed by the guest
in PR-mode KVM without trapping.

SPRG4-7 are readable from userspace.  On booke, KVM will sync
these registers when it enters the guest, so that accesses from
guest userspace will work.  The guest kernel, OTOH, must consistently
use either the real registers or the shared area between exits.  This
also applies to the already-paravirted SPRG3.

On non-booke, it's not clear to what extent SPRG4-7 are supported
(they're not architected for book3s, but exist on at least some classic
chips).  They are copied in the get/set regs ioctls, but I do not see any
non-booke emulation.  I also do not see any syncing with real registers
(in PR-mode) including the user-readable SPRG3.  This patch should not
make that situation any worse.
Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>
      b5904972
    • S
      KVM: PPC: e500: Don't hardcode PIR=0 · 841741f2
      由 Scott Wood 提交于 
      The hardcoded behavior prevents proper SMP support.

user space shall specify the vcpu's PIR as the vcpu id.
Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>
      841741f2
    • S
      KVM: PPC: e500: MMU API · dc83b8bc
      由 Scott Wood 提交于 
      This implements a shared-memory API for giving host userspace access to
the guest's TLB.
Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>
      dc83b8bc
  17. 26 12月, 2011 1 次提交
  19. 26 9月, 2011 1 次提交
    • A
      KVM: PPC: Add sanity checking to vcpu_run · af8f38b3
      由 Alexander Graf 提交于 
      There are multiple features in PowerPC KVM that can now be enabled
depending on the user's wishes. Some of the combinations don't make
sense or don't work though.

So this patch adds a way to check if the executing environment would
actually be able to run the guest properly. It also adds sanity
checks if PVR is set (should always be true given the current code
flow), if PAPR is only used with book3s_64 where it works and that
HV KVM is only used in PAPR mode.
Signed-off-by: NAlexander Graf <agraf@suse.de>
      af8f38b3
  21. 12 7月, 2011 1 次提交
  23. 22 5月, 2011 2 次提交
  25. 06 11月, 2010 1 次提交
  27. 24 10月, 2010 1 次提交
    • A
      KVM: PPC: Introduce shared page · 96bc451a
      由 Alexander Graf 提交于 
      For transparent variable sharing between the hypervisor and guest, I introduce
a shared page. This shared page will contain all the registers the guest can
read and write safely without exiting guest context.

This patch only implements the stubs required for the basic structure of the
shared page. The actual register moving follows.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>
      96bc451a
  29. 09 6月, 2010 1 次提交
  31. 19 5月, 2010 1 次提交
  33. 30 3月, 2010 1 次提交
    • T
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking... · 5a0e3ad6
      由 Tejun Heo 提交于 
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
      5a0e3ad6
  35. 01 3月, 2010 1 次提交
  37. 10 9月, 2009 2 次提交
  39. 24 3月, 2009 2 次提交