<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/arch/ia64/kernel, branch v3.18.3</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>Merge branch 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2014-10-23T21:45:09+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2014-10-23T21:45:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8c81f48e16fbe103e682d7ee7b2f16d065c42954'/>
<id>8c81f48e16fbe103e682d7ee7b2f16d065c42954</id>
<content type='text'>
Pull x86 EFI updates from Peter Anvin:
 "This patchset falls under the "maintainers that grovel" clause in the
  v3.18-rc1 announcement.  We had intended to push it late in the merge
  window since we got it into the -tip tree relatively late.

  Many of these are relatively simple things, but there are a couple of
  key bits, especially Ard's and Matt's patches"

* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  rtc: Disable EFI rtc for x86
  efi: rtc-efi: Export platform:rtc-efi as module alias
  efi: Delete the in_nmi() conditional runtime locking
  efi: Provide a non-blocking SetVariable() operation
  x86/efi: Adding efi_printks on memory allocationa and pci.reads
  x86/efi: Mark initialization code as such
  x86/efi: Update comment regarding required phys mapped EFI services
  x86/efi: Unexport add_efi_memmap variable
  x86/efi: Remove unused efi_call* macros
  efi: Resolve some shadow warnings
  arm64: efi: Format EFI memory type &amp; attrs with efi_md_typeattr_format()
  ia64: efi: Format EFI memory type &amp; attrs with efi_md_typeattr_format()
  x86: efi: Format EFI memory type &amp; attrs with efi_md_typeattr_format()
  efi: Introduce efi_md_typeattr_format()
  efi: Add macro for EFI_MEMORY_UCE memory attribute
  x86/efi: Clear EFI_RUNTIME_SERVICES if failing to enter virtual mode
  arm64/efi: Do not enter virtual mode if booting with efi=noruntime or noefi
  arm64/efi: uefi_init error handling fix
  efi: Add kernel param efi=noruntime
  lib: Add a generic cmdline parse function parse_option_str
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull x86 EFI updates from Peter Anvin:
 "This patchset falls under the "maintainers that grovel" clause in the
  v3.18-rc1 announcement.  We had intended to push it late in the merge
  window since we got it into the -tip tree relatively late.

  Many of these are relatively simple things, but there are a couple of
  key bits, especially Ard's and Matt's patches"

* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  rtc: Disable EFI rtc for x86
  efi: rtc-efi: Export platform:rtc-efi as module alias
  efi: Delete the in_nmi() conditional runtime locking
  efi: Provide a non-blocking SetVariable() operation
  x86/efi: Adding efi_printks on memory allocationa and pci.reads
  x86/efi: Mark initialization code as such
  x86/efi: Update comment regarding required phys mapped EFI services
  x86/efi: Unexport add_efi_memmap variable
  x86/efi: Remove unused efi_call* macros
  efi: Resolve some shadow warnings
  arm64: efi: Format EFI memory type &amp; attrs with efi_md_typeattr_format()
  ia64: efi: Format EFI memory type &amp; attrs with efi_md_typeattr_format()
  x86: efi: Format EFI memory type &amp; attrs with efi_md_typeattr_format()
  efi: Introduce efi_md_typeattr_format()
  efi: Add macro for EFI_MEMORY_UCE memory attribute
  x86/efi: Clear EFI_RUNTIME_SERVICES if failing to enter virtual mode
  arm64/efi: Do not enter virtual mode if booting with efi=noruntime or noefi
  arm64/efi: uefi_init error handling fix
  efi: Add kernel param efi=noruntime
  lib: Add a generic cmdline parse function parse_option_str
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge git://git.infradead.org/users/eparis/audit</title>
<updated>2014-10-19T23:25:56+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2014-10-19T23:25:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=ab074ade9c33b3585da86d62e87bcb3e897a3f54'/>
<id>ab074ade9c33b3585da86d62e87bcb3e897a3f54</id>
<content type='text'>
Pull audit updates from Eric Paris:
 "So this change across a whole bunch of arches really solves one basic
  problem.  We want to audit when seccomp is killing a process.  seccomp
  hooks in before the audit syscall entry code.  audit_syscall_entry
  took as an argument the arch of the given syscall.  Since the arch is
  part of what makes a syscall number meaningful it's an important part
  of the record, but it isn't available when seccomp shoots the
  syscall...

  For most arch's we have a better way to get the arch (syscall_get_arch)
  So the solution was two fold: Implement syscall_get_arch() everywhere
  there is audit which didn't have it.  Use syscall_get_arch() in the
  seccomp audit code.  Having syscall_get_arch() everywhere meant it was
  a useless flag on the stack and we could get rid of it for the typical
  syscall entry.

  The other changes inside the audit system aren't grand, fixed some
  records that had invalid spaces.  Better locking around the task comm
  field.  Removing some dead functions and structs.  Make some things
  static.  Really minor stuff"

* git://git.infradead.org/users/eparis/audit: (31 commits)
  audit: rename audit_log_remove_rule to disambiguate for trees
  audit: cull redundancy in audit_rule_change
  audit: WARN if audit_rule_change called illegally
  audit: put rule existence check in canonical order
  next: openrisc: Fix build
  audit: get comm using lock to avoid race in string printing
  audit: remove open_arg() function that is never used
  audit: correct AUDIT_GET_FEATURE return message type
  audit: set nlmsg_len for multicast messages.
  audit: use union for audit_field values since they are mutually exclusive
  audit: invalid op= values for rules
  audit: use atomic_t to simplify audit_serial()
  kernel/audit.c: use ARRAY_SIZE instead of sizeof/sizeof[0]
  audit: reduce scope of audit_log_fcaps
  audit: reduce scope of audit_net_id
  audit: arm64: Remove the audit arch argument to audit_syscall_entry
  arm64: audit: Add audit hook in syscall_trace_enter/exit()
  audit: x86: drop arch from __audit_syscall_entry() interface
  sparc: implement is_32bit_task
  sparc: properly conditionalize use of TIF_32BIT
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull audit updates from Eric Paris:
 "So this change across a whole bunch of arches really solves one basic
  problem.  We want to audit when seccomp is killing a process.  seccomp
  hooks in before the audit syscall entry code.  audit_syscall_entry
  took as an argument the arch of the given syscall.  Since the arch is
  part of what makes a syscall number meaningful it's an important part
  of the record, but it isn't available when seccomp shoots the
  syscall...

  For most arch's we have a better way to get the arch (syscall_get_arch)
  So the solution was two fold: Implement syscall_get_arch() everywhere
  there is audit which didn't have it.  Use syscall_get_arch() in the
  seccomp audit code.  Having syscall_get_arch() everywhere meant it was
  a useless flag on the stack and we could get rid of it for the typical
  syscall entry.

  The other changes inside the audit system aren't grand, fixed some
  records that had invalid spaces.  Better locking around the task comm
  field.  Removing some dead functions and structs.  Make some things
  static.  Really minor stuff"

* git://git.infradead.org/users/eparis/audit: (31 commits)
  audit: rename audit_log_remove_rule to disambiguate for trees
  audit: cull redundancy in audit_rule_change
  audit: WARN if audit_rule_change called illegally
  audit: put rule existence check in canonical order
  next: openrisc: Fix build
  audit: get comm using lock to avoid race in string printing
  audit: remove open_arg() function that is never used
  audit: correct AUDIT_GET_FEATURE return message type
  audit: set nlmsg_len for multicast messages.
  audit: use union for audit_field values since they are mutually exclusive
  audit: invalid op= values for rules
  audit: use atomic_t to simplify audit_serial()
  kernel/audit.c: use ARRAY_SIZE instead of sizeof/sizeof[0]
  audit: reduce scope of audit_log_fcaps
  audit: reduce scope of audit_net_id
  audit: arm64: Remove the audit arch argument to audit_syscall_entry
  arm64: audit: Add audit hook in syscall_trace_enter/exit()
  audit: x86: drop arch from __audit_syscall_entry() interface
  sparc: implement is_32bit_task
  sparc: properly conditionalize use of TIF_32BIT
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu</title>
<updated>2014-10-15T05:48:18+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2014-10-15T05:48:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=0429fbc0bdc297d64188483ba029a23773ae07b0'/>
<id>0429fbc0bdc297d64188483ba029a23773ae07b0</id>
<content type='text'>
Pull percpu consistent-ops changes from Tejun Heo:
 "Way back, before the current percpu allocator was implemented, static
  and dynamic percpu memory areas were allocated and handled separately
  and had their own accessors.  The distinction has been gone for many
  years now; however, the now duplicate two sets of accessors remained
  with the pointer based ones - this_cpu_*() - evolving various other
  operations over time.  During the process, we also accumulated other
  inconsistent operations.

  This pull request contains Christoph's patches to clean up the
  duplicate accessor situation.  __get_cpu_var() uses are replaced with
  with this_cpu_ptr() and __this_cpu_ptr() with raw_cpu_ptr().

  Unfortunately, the former sometimes is tricky thanks to C being a bit
  messy with the distinction between lvalues and pointers, which led to
  a rather ugly solution for cpumask_var_t involving the introduction of
  this_cpu_cpumask_var_ptr().

  This converts most of the uses but not all.  Christoph will follow up
  with the remaining conversions in this merge window and hopefully
  remove the obsolete accessors"

* 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (38 commits)
  irqchip: Properly fetch the per cpu offset
  percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t -fix
  ia64: sn_nodepda cannot be assigned to after this_cpu conversion. Use __this_cpu_write.
  percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t
  Revert "powerpc: Replace __get_cpu_var uses"
  percpu: Remove __this_cpu_ptr
  clocksource: Replace __this_cpu_ptr with raw_cpu_ptr
  sparc: Replace __get_cpu_var uses
  avr32: Replace __get_cpu_var with __this_cpu_write
  blackfin: Replace __get_cpu_var uses
  tile: Use this_cpu_ptr() for hardware counters
  tile: Replace __get_cpu_var uses
  powerpc: Replace __get_cpu_var uses
  alpha: Replace __get_cpu_var
  ia64: Replace __get_cpu_var uses
  s390: cio driver &amp;__get_cpu_var replacements
  s390: Replace __get_cpu_var uses
  mips: Replace __get_cpu_var uses
  MIPS: Replace __get_cpu_var uses in FPU emulator.
  arm: Replace __this_cpu_ptr with raw_cpu_ptr
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull percpu consistent-ops changes from Tejun Heo:
 "Way back, before the current percpu allocator was implemented, static
  and dynamic percpu memory areas were allocated and handled separately
  and had their own accessors.  The distinction has been gone for many
  years now; however, the now duplicate two sets of accessors remained
  with the pointer based ones - this_cpu_*() - evolving various other
  operations over time.  During the process, we also accumulated other
  inconsistent operations.

  This pull request contains Christoph's patches to clean up the
  duplicate accessor situation.  __get_cpu_var() uses are replaced with
  with this_cpu_ptr() and __this_cpu_ptr() with raw_cpu_ptr().

  Unfortunately, the former sometimes is tricky thanks to C being a bit
  messy with the distinction between lvalues and pointers, which led to
  a rather ugly solution for cpumask_var_t involving the introduction of
  this_cpu_cpumask_var_ptr().

  This converts most of the uses but not all.  Christoph will follow up
  with the remaining conversions in this merge window and hopefully
  remove the obsolete accessors"

* 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (38 commits)
  irqchip: Properly fetch the per cpu offset
  percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t -fix
  ia64: sn_nodepda cannot be assigned to after this_cpu conversion. Use __this_cpu_write.
  percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t
  Revert "powerpc: Replace __get_cpu_var uses"
  percpu: Remove __this_cpu_ptr
  clocksource: Replace __this_cpu_ptr with raw_cpu_ptr
  sparc: Replace __get_cpu_var uses
  avr32: Replace __get_cpu_var with __this_cpu_write
  blackfin: Replace __get_cpu_var uses
  tile: Use this_cpu_ptr() for hardware counters
  tile: Replace __get_cpu_var uses
  powerpc: Replace __get_cpu_var uses
  alpha: Replace __get_cpu_var
  ia64: Replace __get_cpu_var uses
  s390: cio driver &amp;__get_cpu_var replacements
  s390: Replace __get_cpu_var uses
  mips: Replace __get_cpu_var uses
  MIPS: Replace __get_cpu_var uses in FPU emulator.
  arm: Replace __this_cpu_ptr with raw_cpu_ptr
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'please-pull-sys_bpf' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux</title>
<updated>2014-10-14T01:50:34+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2014-10-14T01:50:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=fc2414b4b4569fab5404c6f49f36bae0dfa3d936'/>
<id>fc2414b4b4569fab5404c6f49f36bae0dfa3d936</id>
<content type='text'>
Pull ia64 update from Tony Luck:
 "Wire up bpf syscall for ia64"

* tag 'please-pull-sys_bpf' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux:
  [IA64] Enable bpf syscall for ia64
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull ia64 update from Tony Luck:
 "Wire up bpf syscall for ia64"

* tag 'please-pull-sys_bpf' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux:
  [IA64] Enable bpf syscall for ia64
</pre>
</div>
</content>
</entry>
<entry>
<title>[IA64] Enable bpf syscall for ia64</title>
<updated>2014-10-09T20:36:10+00:00</updated>
<author>
<name>Tony Luck</name>
<email>tony.luck@intel.com</email>
</author>
<published>2014-10-09T20:26:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=5dab4b73c736c2cb8e35148f9ee2365ee48bad79'/>
<id>5dab4b73c736c2cb8e35148f9ee2365ee48bad79</id>
<content type='text'>
See commit 99c55f7d47c0dc6fc64729f37bf435abf43f4c60
   bpf: introduce BPF syscall and maps

Signed-off-by: Tony Luck &lt;tony.luck@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
See commit 99c55f7d47c0dc6fc64729f37bf435abf43f4c60
   bpf: introduce BPF syscall and maps

Signed-off-by: Tony Luck &lt;tony.luck@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'next' into efi-next-merge</title>
<updated>2014-10-03T21:15:56+00:00</updated>
<author>
<name>Matt Fleming</name>
<email>matt.fleming@intel.com</email>
</author>
<published>2014-10-03T21:15:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=75b128573b275d5a5a7210b98c4b8cb3b39c12e7'/>
<id>75b128573b275d5a5a7210b98c4b8cb3b39c12e7</id>
<content type='text'>
Conflicts:
	arch/x86/boot/compressed/eboot.c
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Conflicts:
	arch/x86/boot/compressed/eboot.c
</pre>
</div>
</content>
</entry>
<entry>
<title>ia64: efi: Format EFI memory type &amp; attrs with efi_md_typeattr_format()</title>
<updated>2014-10-03T17:41:01+00:00</updated>
<author>
<name>Laszlo Ersek</name>
<email>lersek@redhat.com</email>
</author>
<published>2014-09-03T11:32:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=77b12bcfc532b6bb9adc0f898c6b08216056eb89'/>
<id>77b12bcfc532b6bb9adc0f898c6b08216056eb89</id>
<content type='text'>
The effects of the patch on the i64 memory map log are similar to those
visible in the previous (x86) patch: the type enum and the attribute
bitmap are decoded.

Signed-off-by: Laszlo Ersek &lt;lersek@redhat.com&gt;
Acked-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Matt Fleming &lt;matt.fleming@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The effects of the patch on the i64 memory map log are similar to those
visible in the previous (x86) patch: the type enum and the attribute
bitmap are decoded.

Signed-off-by: Laszlo Ersek &lt;lersek@redhat.com&gt;
Acked-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Matt Fleming &lt;matt.fleming@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PCI/MSI: Use __get_cached_msi_msg() instead of get_cached_msi_msg()</title>
<updated>2014-10-01T18:21:23+00:00</updated>
<author>
<name>Yijing Wang</name>
<email>wangyijing@huawei.com</email>
</author>
<published>2014-09-23T05:27:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=2b260085e466c345e78f23b1c9ad1d123d509ef8'/>
<id>2b260085e466c345e78f23b1c9ad1d123d509ef8</id>
<content type='text'>
Both callers of get_cached_msi_msg() start with a struct irq_data pointer,
look up the corresponding IRQ number, and pass it to get_cached_msi_msg(),
which then uses irq_get_irq_data() to look up the struct irq_data again to
call __get_cached_msi_msg().

Since we already have the struct irq_data, call __get_cached_msi_msg()
directly and skip the lookup work done by get_cached_msi_msg().

No functional change.

[bhelgaas: changelog]
Signed-off-by: Yijing Wang &lt;wangyijing@huawei.com&gt;
Signed-off-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
CC: Tony Luck &lt;tony.luck@intel.com&gt;
CC: linux-ia64@vger.kernel.org</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Both callers of get_cached_msi_msg() start with a struct irq_data pointer,
look up the corresponding IRQ number, and pass it to get_cached_msi_msg(),
which then uses irq_get_irq_data() to look up the struct irq_data again to
call __get_cached_msi_msg().

Since we already have the struct irq_data, call __get_cached_msi_msg()
directly and skip the lookup work done by get_cached_msi_msg().

No functional change.

[bhelgaas: changelog]
Signed-off-by: Yijing Wang &lt;wangyijing@huawei.com&gt;
Signed-off-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
CC: Tony Luck &lt;tony.luck@intel.com&gt;
CC: linux-ia64@vger.kernel.org</pre>
</div>
</content>
</entry>
<entry>
<title>ARCH: AUDIT: audit_syscall_entry() should not require the arch</title>
<updated>2014-09-23T20:21:26+00:00</updated>
<author>
<name>Eric Paris</name>
<email>eparis@redhat.com</email>
</author>
<published>2014-03-11T17:29:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=91397401bb5072f71e8ce8744ad0bdec3e875a91'/>
<id>91397401bb5072f71e8ce8744ad0bdec3e875a91</id>
<content type='text'>
We have a function where the arch can be queried, syscall_get_arch().
So rather than have every single piece of arch specific code use and/or
duplicate syscall_get_arch(), just have the audit code use the
syscall_get_arch() code.

Based-on-patch-by: Richard Briggs &lt;rgb@redhat.com&gt;
Signed-off-by: Eric Paris &lt;eparis@redhat.com&gt;
Cc: linux-alpha@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-ia64@vger.kernel.org
Cc: microblaze-uclinux@itee.uq.edu.au
Cc: linux-mips@linux-mips.org
Cc: linux@lists.openrisc.net
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Cc: user-mode-linux-devel@lists.sourceforge.net
Cc: linux-xtensa@linux-xtensa.org
Cc: x86@kernel.org
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We have a function where the arch can be queried, syscall_get_arch().
So rather than have every single piece of arch specific code use and/or
duplicate syscall_get_arch(), just have the audit code use the
syscall_get_arch() code.

Based-on-patch-by: Richard Briggs &lt;rgb@redhat.com&gt;
Signed-off-by: Eric Paris &lt;eparis@redhat.com&gt;
Cc: linux-alpha@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-ia64@vger.kernel.org
Cc: microblaze-uclinux@itee.uq.edu.au
Cc: linux-mips@linux-mips.org
Cc: linux@lists.openrisc.net
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Cc: user-mode-linux-devel@lists.sourceforge.net
Cc: linux-xtensa@linux-xtensa.org
Cc: x86@kernel.org
</pre>
</div>
</content>
</entry>
<entry>
<title>ia64: Replace __get_cpu_var uses</title>
<updated>2014-08-26T17:45:52+00:00</updated>
<author>
<name>Christoph Lameter</name>
<email>cl@linux.com</email>
</author>
<published>2014-08-17T17:30:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=6065a244a039a23d933e4b803a4e052da2849208'/>
<id>6065a244a039a23d933e4b803a4e052da2849208</id>
<content type='text'>
__get_cpu_var() is used for multiple purposes in the kernel source. One of
them is address calculation via the form &amp;__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(&amp;(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 = &amp;__get_cpu_var(y);

    Converts to

	int *x = this_cpu_ptr(&amp;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(&amp;x, this_cpu_ptr(&amp;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: Tony Luck &lt;tony.luck@intel.com&gt;
Cc: Fenghua Yu &lt;fenghua.yu@intel.com&gt;
Cc: linux-ia64@vger.kernel.org
Signed-off-by: Christoph Lameter &lt;cl@linux.com&gt;
Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
__get_cpu_var() is used for multiple purposes in the kernel source. One of
them is address calculation via the form &amp;__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(&amp;(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 = &amp;__get_cpu_var(y);

    Converts to

	int *x = this_cpu_ptr(&amp;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(&amp;x, this_cpu_ptr(&amp;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: Tony Luck &lt;tony.luck@intel.com&gt;
Cc: Fenghua Yu &lt;fenghua.yu@intel.com&gt;
Cc: linux-ia64@vger.kernel.org
Signed-off-by: Christoph Lameter &lt;cl@linux.com&gt;
Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
</pre>
</div>
</content>
</entry>
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