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  1. 10 5月, 2018 1 次提交
  3. 22 1月, 2018 1 次提交
    • R
      powerpc: Use octal numbers for file permissions · 57ad583f
      由 Russell Currey 提交于 
      Symbolic macros are unintuitive and hard to read, whereas octal constants
are much easier to interpret.  Replace macros for the basic permission
flags (user/group/other read/write/execute) with numeric constants
instead, across the whole powerpc tree.

Introducing a significant number of changes across the tree for no runtime
benefit isn't exactly desirable, but so long as these macros are still
used in the tree people will keep sending patches that add them.  Not only
are they hard to parse at a glance, there are multiple ways of coming to
the same value (as you can see with 0444 and 0644 in this patch) which
hurts readability.
Signed-off-by: NRussell Currey <ruscur@russell.cc>
Reviewed-by: NCyril Bur <cyrilbur@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      57ad583f
  5. 20 3月, 2017 1 次提交
  7. 03 11月, 2014 1 次提交
    • C
      powerpc: Replace __get_cpu_var uses · 69111bac
      由 Christoph Lameter 提交于 
      This still has not been merged and now powerpc is the only arch that does
not have this change. Sorry about missing linuxppc-dev before.

V2->V2
  - Fix up to work against 3.18-rc1

__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 :

__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)

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
Signed-off-by: NChristoph Lameter <cl@linux.com>
[mpe: Fix build errors caused by set/or_softirq_pending(), and rework
      assignment in __set_breakpoint() to use memcpy().]
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      69111bac
  9. 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
  11. 28 7月, 2014 1 次提交
    • M
      powerpc/pseries: Switch pseries drivers to use machine_xxx_initcall() · 8e83e905
      由 Michael Ellerman 提交于 
      A lot of the code in platforms/pseries is using non-machine initcalls.
That means if a kernel built with pseries support runs on another
platform, for example powernv, the initcalls will still run.

Most of these cases are OK, though sometimes only due to luck. Some were
having more effect:

 * hcall_inst_init
  - Checking FW_FEATURE_LPAR which is set on ps3 & celleb.
 * mobility_sysfs_init
  - created sysfs files unconditionally
  - but no effect due to ENOSYS from rtas_ibm_suspend_me()
 * apo_pm_init
  - created sysfs, allows write
  - nothing checks the value written to though
 * alloc_dispatch_log_kmem_cache
  - creating kmem_cache on non-pseries machines
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
      8e83e905
  13. 23 2月, 2013 1 次提交
  15. 03 1月, 2012 1 次提交
  17. 03 11月, 2010 1 次提交
  19. 29 5月, 2010 1 次提交
  21. 09 2月, 2010 1 次提交
  23. 28 10月, 2009 2 次提交
  25. 23 9月, 2009 1 次提交
  27. 13 2月, 2007 1 次提交
  29. 09 1月, 2007 1 次提交
    • A
      [POWERPC] Fix bugs in the hypervisor call stats code · dc40127c
      由 Anton Blanchard 提交于 
      There were a few issues with the HCALL_STATS code:

- PURR cpu feature checks were backwards
- We iterated one entry off the end of the hcall_stats array
- Remove dead update_hcall_stats() function prototype

I noticed one thing while debugging, and that is we call H_ENTER (to set
up the MMU hashtable in early init) before we have done the cpu fixups.
This means we will execute the PURR SPR reads even on a CPU that isnt
capable of it. I wonder if we can move the CPU feature fixups earlier.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>
      dc40127c
  31. 09 12月, 2006 1 次提交
  33. 27 9月, 2006 1 次提交
    • T
      [PATCH] inode_diet: Replace inode.u.generic_ip with inode.i_private · 8e18e294
      由 Theodore Ts'o 提交于 
      The following patches reduce the size of the VFS inode structure by 28 bytes
on a UP x86.  (It would be more on an x86_64 system).  This is a 10% reduction
in the inode size on a UP kernel that is configured in a production mode
(i.e., with no spinlock or other debugging functions enabled; if you want to
save memory taken up by in-core inodes, the first thing you should do is
disable the debugging options; they are responsible for a huge amount of bloat
in the VFS inode structure).

This patch:

The filesystem or device-specific pointer in the inode is inside a union,
which is pretty pointless given that all 30+ users of this field have been
using the void pointer.  Get rid of the union and rename it to i_private, with
a comment to explain who is allowed to use the void pointer.  This is just a
cleanup, but it allows us to reuse the union 'u' for something something where
the union will actually be used.

[judith@osdl.org: powerpc build fix]
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: NJudith Lebzelter <judith@osdl.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      8e18e294
  35. 13 9月, 2006 1 次提交