<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch/sparc/include/asm, branch v3.17</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>lib/scatterlist: make ARCH_HAS_SG_CHAIN an actual Kconfig</title>
<updated>2014-08-08T22:57:26+00:00</updated>
<author>
<name>Laura Abbott</name>
<email>lauraa@codeaurora.org</email>
</author>
<published>2014-08-08T21:23:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=308c09f17da4adc53935115dbeb5bce4f067d8f9'/>
<id>308c09f17da4adc53935115dbeb5bce4f067d8f9</id>
<content type='text'>
Rather than have architectures #define ARCH_HAS_SG_CHAIN in an
architecture specific scatterlist.h, make it a proper Kconfig option and
use that instead.  At same time, remove the header files are are now
mostly useless and just include asm-generic/scatterlist.h.

[sfr@canb.auug.org.au: powerpc files now need asm/dma.h]
Signed-off-by: Laura Abbott &lt;lauraa@codeaurora.org&gt;
Acked-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;			[x86]
Acked-by: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;	[powerpc]
Acked-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Russell King &lt;linux@arm.linux.org.uk&gt;
Cc: Tony Luck &lt;tony.luck@intel.com&gt;
Cc: Fenghua Yu &lt;fenghua.yu@intel.com&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: "James E.J. Bottomley" &lt;JBottomley@parallels.com&gt;
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Signed-off-by: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Rather than have architectures #define ARCH_HAS_SG_CHAIN in an
architecture specific scatterlist.h, make it a proper Kconfig option and
use that instead.  At same time, remove the header files are are now
mostly useless and just include asm-generic/scatterlist.h.

[sfr@canb.auug.org.au: powerpc files now need asm/dma.h]
Signed-off-by: Laura Abbott &lt;lauraa@codeaurora.org&gt;
Acked-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;			[x86]
Acked-by: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;	[powerpc]
Acked-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Russell King &lt;linux@arm.linux.org.uk&gt;
Cc: Tony Luck &lt;tony.luck@intel.com&gt;
Cc: Fenghua Yu &lt;fenghua.yu@intel.com&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: "James E.J. Bottomley" &lt;JBottomley@parallels.com&gt;
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Signed-off-by: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next</title>
<updated>2014-08-06T16:41:23+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2014-08-06T16:41:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=049711bf3cc59501ebeae621aa22acd3918ebd79'/>
<id>049711bf3cc59501ebeae621aa22acd3918ebd79</id>
<content type='text'>
Pull sparc updates from David Miller:

 1) Add sparc RAM output to /proc/iomem, from Bob Picco.

 2) Allow seeks on /dev/mdesc, from Khalid Aziz.

 3) Cleanup sparc64 I/O accessors, from Sam Ravnborg.

 4) If update_mmu_cache{,_pmd}() is called with an not-valid mapping, do
    not insert it into the TLB miss hash tables otherwise we'll
    livelock.  Based upon work by Christopher Alexander Tobias Schulze.

 5) Fix BREAK detection in sunsab driver when no actual characters are
    pending, from Christopher Alexander Tobias Schulze.

 6) Because we have modules --&gt; openfirmware --&gt; vmalloc ordering of
    virtual memory, the lazy VMAP TLB flusher can cons up an invocation
    of flush_tlb_kernel_range() that covers the openfirmware address
    range.  Unfortunately this will flush out the firmware's locked TLB
    mapping which causes all kinds of trouble.  Just split up the flush
    request if this happens, but in the long term the lazy VMAP flusher
    should probably be made a little bit smarter.

    Based upon work by Christopher Alexander Tobias Schulze.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next:
  sparc64: Fix up merge thinko.
  sparc: Add "install" target
  arch/sparc/math-emu/math_32.c: drop stray break operator
  sparc64: ldc_connect() should not return EINVAL when handshake is in progress.
  sparc64: Guard against flushing openfirmware mappings.
  sunsab: Fix detection of BREAK on sunsab serial console
  bbc-i2c: Fix BBC I2C envctrl on SunBlade 2000
  sparc64: Do not insert non-valid PTEs into the TSB hash table.
  sparc64: avoid code duplication in io_64.h
  sparc64: reorder functions in io_64.h
  sparc64: drop unused SLOW_DOWN_IO definitions
  sparc64: remove macro indirection in io_64.h
  sparc64: update IO access functions in PeeCeeI
  sparcspkr: use sbus_*() primitives for IO
  sparc: Add support for seek and shorter read to /dev/mdesc
  sparc: use %s for unaligned panic
  drivers/sbus/char: Micro-optimization in display7seg.c
  display7seg: Introduce the use of the managed version of kzalloc
  sparc64 - add mem to iomem resource
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull sparc updates from David Miller:

 1) Add sparc RAM output to /proc/iomem, from Bob Picco.

 2) Allow seeks on /dev/mdesc, from Khalid Aziz.

 3) Cleanup sparc64 I/O accessors, from Sam Ravnborg.

 4) If update_mmu_cache{,_pmd}() is called with an not-valid mapping, do
    not insert it into the TLB miss hash tables otherwise we'll
    livelock.  Based upon work by Christopher Alexander Tobias Schulze.

 5) Fix BREAK detection in sunsab driver when no actual characters are
    pending, from Christopher Alexander Tobias Schulze.

 6) Because we have modules --&gt; openfirmware --&gt; vmalloc ordering of
    virtual memory, the lazy VMAP TLB flusher can cons up an invocation
    of flush_tlb_kernel_range() that covers the openfirmware address
    range.  Unfortunately this will flush out the firmware's locked TLB
    mapping which causes all kinds of trouble.  Just split up the flush
    request if this happens, but in the long term the lazy VMAP flusher
    should probably be made a little bit smarter.

    Based upon work by Christopher Alexander Tobias Schulze.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next:
  sparc64: Fix up merge thinko.
  sparc: Add "install" target
  arch/sparc/math-emu/math_32.c: drop stray break operator
  sparc64: ldc_connect() should not return EINVAL when handshake is in progress.
  sparc64: Guard against flushing openfirmware mappings.
  sunsab: Fix detection of BREAK on sunsab serial console
  bbc-i2c: Fix BBC I2C envctrl on SunBlade 2000
  sparc64: Do not insert non-valid PTEs into the TSB hash table.
  sparc64: avoid code duplication in io_64.h
  sparc64: reorder functions in io_64.h
  sparc64: drop unused SLOW_DOWN_IO definitions
  sparc64: remove macro indirection in io_64.h
  sparc64: update IO access functions in PeeCeeI
  sparcspkr: use sbus_*() primitives for IO
  sparc: Add support for seek and shorter read to /dev/mdesc
  sparc: use %s for unaligned panic
  drivers/sbus/char: Micro-optimization in display7seg.c
  display7seg: Introduce the use of the managed version of kzalloc
  sparc64 - add mem to iomem resource
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc</title>
<updated>2014-08-06T01:57:18+00:00</updated>
<author>
<name>David S. Miller</name>
<email>davem@davemloft.net</email>
</author>
<published>2014-08-06T01:57:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e9011d086674caeedb0ffb6eb5b8bc5920821df3'/>
<id>e9011d086674caeedb0ffb6eb5b8bc5920821df3</id>
<content type='text'>
Conflicts:
	arch/sparc/mm/init_64.c

Conflict was simple non-overlapping additions.

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Conflicts:
	arch/sparc/mm/init_64.c

Conflict was simple non-overlapping additions.

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sparc64: Guard against flushing openfirmware mappings.</title>
<updated>2014-08-05T03:16:00+00:00</updated>
<author>
<name>David S. Miller</name>
<email>davem@davemloft.net</email>
</author>
<published>2014-08-05T03:07:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4ca9a23765da3260058db3431faf5b4efd8cf926'/>
<id>4ca9a23765da3260058db3431faf5b4efd8cf926</id>
<content type='text'>
Based almost entirely upon a patch by Christopher Alexander Tobias
Schulze.

In commit db64fe02258f1507e13fe5212a989922323685ce ("mm: rewrite vmap
layer") lazy VMAP tlb flushing was added to the vmalloc layer.  This
causes problems on sparc64.

Sparc64 has two VMAP mapped regions and they are not contiguous with
eachother.  First we have the malloc mapping area, then another
unrelated region, then the vmalloc region.

This "another unrelated region" is where the firmware is mapped.

If the lazy TLB flushing logic in the vmalloc code triggers after
we've had both a module unload and a vfree or similar, it will pass an
address range that goes from somewhere inside the malloc region to
somewhere inside the vmalloc region, and thus covering the
openfirmware area entirely.

The sparc64 kernel learns about openfirmware's dynamic mappings in
this region early in the boot, and then services TLB misses in this
area.  But openfirmware has some locked TLB entries which are not
mentioned in those dynamic mappings and we should thus not disturb
them.

These huge lazy TLB flush ranges causes those openfirmware locked TLB
entries to be removed, resulting in all kinds of problems including
hard hangs and crashes during reboot/reset.

Besides causing problems like this, such huge TLB flush ranges are
also incredibly inefficient.  A plea has been made with the author of
the VMAP lazy TLB flushing code, but for now we'll put a safety guard
into our flush_tlb_kernel_range() implementation.

Since the implementation has become non-trivial, stop defining it as a
macro and instead make it a function in a C source file.

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Based almost entirely upon a patch by Christopher Alexander Tobias
Schulze.

In commit db64fe02258f1507e13fe5212a989922323685ce ("mm: rewrite vmap
layer") lazy VMAP tlb flushing was added to the vmalloc layer.  This
causes problems on sparc64.

Sparc64 has two VMAP mapped regions and they are not contiguous with
eachother.  First we have the malloc mapping area, then another
unrelated region, then the vmalloc region.

This "another unrelated region" is where the firmware is mapped.

If the lazy TLB flushing logic in the vmalloc code triggers after
we've had both a module unload and a vfree or similar, it will pass an
address range that goes from somewhere inside the malloc region to
somewhere inside the vmalloc region, and thus covering the
openfirmware area entirely.

The sparc64 kernel learns about openfirmware's dynamic mappings in
this region early in the boot, and then services TLB misses in this
area.  But openfirmware has some locked TLB entries which are not
mentioned in those dynamic mappings and we should thus not disturb
them.

These huge lazy TLB flush ranges causes those openfirmware locked TLB
entries to be removed, resulting in all kinds of problems including
hard hangs and crashes during reboot/reset.

Besides causing problems like this, such huge TLB flush ranges are
also incredibly inefficient.  A plea has been made with the author of
the VMAP lazy TLB flushing code, but for now we'll put a safety guard
into our flush_tlb_kernel_range() implementation.

Since the implementation has become non-trivial, stop defining it as a
macro and instead make it a function in a C source file.

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sparc64: avoid code duplication in io_64.h</title>
<updated>2014-07-22T04:43:19+00:00</updated>
<author>
<name>Sam Ravnborg</name>
<email>sam@ravnborg.org</email>
</author>
<published>2014-07-20T11:39:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=453c9abd38910cc36a59d503fac15a2d0f4d36c7'/>
<id>453c9abd38910cc36a59d503fac15a2d0f4d36c7</id>
<content type='text'>
Several of the small IO functions ended up having the same implementation.
Use __raw_{read,write}* + {read,write}* as base for the others.

Continue to use static inline functions to get full type check.
The size of vmlinux for a defconfig build was the same when
using static inline and macros for the functions - so there
was no size win when using macros.

This was tested with gcc 4.8.2 + binutils 2.24.
For such simple constructs I assume older gcc's will
do the same job.

Signed-off-by: Sam Ravnborg &lt;sam@ravnborg.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Several of the small IO functions ended up having the same implementation.
Use __raw_{read,write}* + {read,write}* as base for the others.

Continue to use static inline functions to get full type check.
The size of vmlinux for a defconfig build was the same when
using static inline and macros for the functions - so there
was no size win when using macros.

This was tested with gcc 4.8.2 + binutils 2.24.
For such simple constructs I assume older gcc's will
do the same job.

Signed-off-by: Sam Ravnborg &lt;sam@ravnborg.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sparc64: reorder functions in io_64.h</title>
<updated>2014-07-22T04:43:19+00:00</updated>
<author>
<name>Sam Ravnborg</name>
<email>sam@ravnborg.org</email>
</author>
<published>2014-07-20T11:39:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=add79d686c81afb43dcf55924c1f11f59c5d0851'/>
<id>add79d686c81afb43dcf55924c1f11f59c5d0851</id>
<content type='text'>
Reorder functions so __raw_{read,write}* functions comes first,
followed by {read,write}*

Update comments for the two blocks of functions.

Signed-off-by: Sam Ravnborg &lt;sam@ravnborg.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Reorder functions so __raw_{read,write}* functions comes first,
followed by {read,write}*

Update comments for the two blocks of functions.

Signed-off-by: Sam Ravnborg &lt;sam@ravnborg.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sparc64: drop unused SLOW_DOWN_IO definitions</title>
<updated>2014-07-22T04:43:19+00:00</updated>
<author>
<name>Sam Ravnborg</name>
<email>sam@ravnborg.org</email>
</author>
<published>2014-07-20T11:39:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=be80d844c3d2c5f5b83c57f92684b37c69771ada'/>
<id>be80d844c3d2c5f5b83c57f92684b37c69771ada</id>
<content type='text'>
They are no longer used.
All hits in the kernel are essential unused code or comments

Signed-off-by: Sam Ravnborg &lt;sam@ravnborg.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
They are no longer used.
All hits in the kernel are essential unused code or comments

Signed-off-by: Sam Ravnborg &lt;sam@ravnborg.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sparc64: remove macro indirection in io_64.h</title>
<updated>2014-07-22T04:43:19+00:00</updated>
<author>
<name>Sam Ravnborg</name>
<email>sam@ravnborg.org</email>
</author>
<published>2014-07-20T11:39:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=79294d7eff89f65d2e58021bca81437e88fa61e3'/>
<id>79294d7eff89f65d2e58021bca81437e88fa61e3</id>
<content type='text'>
Most likely for historical reasons io_64.h used an
extra layer of macro indirections.

Fix it so we no longer use these indirections.
In the process we loose a cast to the addr argument for in*()/out*()
but all known affected users has already been fixed so
no warnings are triggered.

For each of the IO functions add a proper define like this:

    #define inb inb

This is done to make the code compatible with the way these
functions are defined in asm-generic/io.h with the objective
to later introduce the generic io.h for sparc64.

Signed-off-by: Sam Ravnborg &lt;sam@ravnborg.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Most likely for historical reasons io_64.h used an
extra layer of macro indirections.

Fix it so we no longer use these indirections.
In the process we loose a cast to the addr argument for in*()/out*()
but all known affected users has already been fixed so
no warnings are triggered.

For each of the IO functions add a proper define like this:

    #define inb inb

This is done to make the code compatible with the way these
functions are defined in asm-generic/io.h with the objective
to later introduce the generic io.h for sparc64.

Signed-off-by: Sam Ravnborg &lt;sam@ravnborg.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arch, locking: Ciao arch_mutex_cpu_relax()</title>
<updated>2014-07-17T10:32:47+00:00</updated>
<author>
<name>Davidlohr Bueso</name>
<email>davidlohr@hp.com</email>
</author>
<published>2014-06-29T22:09:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=3a6bfbc91df04b081a44d419e0260bad54abddf7'/>
<id>3a6bfbc91df04b081a44d419e0260bad54abddf7</id>
<content type='text'>
The arch_mutex_cpu_relax() function, introduced by 34b133f, is
hacky and ugly. It was added a few years ago to address the fact
that common cpu_relax() calls include yielding on s390, and thus
impact the optimistic spinning functionality of mutexes. Nowadays
we use this function well beyond mutexes: rwsem, qrwlock, mcs and
lockref. Since the macro that defines the call is in the mutex header,
any users must include mutex.h and the naming is misleading as well.

This patch (i) renames the call to cpu_relax_lowlatency  ("relax, but
only if you can do it with very low latency") and (ii) defines it in
each arch's asm/processor.h local header, just like for regular cpu_relax
functions. On all archs, except s390, cpu_relax_lowlatency is simply cpu_relax,
and thus we can take it out of mutex.h. While this can seem redundant,
I believe it is a good choice as it allows us to move out arch specific
logic from generic locking primitives and enables future(?) archs to
transparently define it, similarly to System Z.

Signed-off-by: Davidlohr Bueso &lt;davidlohr@hp.com&gt;
Signed-off-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Anton Blanchard &lt;anton@samba.org&gt;
Cc: Aurelien Jacquiot &lt;a-jacquiot@ti.com&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Bharat Bhushan &lt;r65777@freescale.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Chen Liqin &lt;liqin.linux@gmail.com&gt;
Cc: Chris Metcalf &lt;cmetcalf@tilera.com&gt;
Cc: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Cc: Chris Zankel &lt;chris@zankel.net&gt;
Cc: David Howells &lt;dhowells@redhat.com&gt;
Cc: David S. Miller &lt;davem@davemloft.net&gt;
Cc: Deepthi Dharwar &lt;deepthi@linux.vnet.ibm.com&gt;
Cc: Dominik Dingel &lt;dingel@linux.vnet.ibm.com&gt;
Cc: Fenghua Yu &lt;fenghua.yu@intel.com&gt;
Cc: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Cc: Guan Xuetao &lt;gxt@mprc.pku.edu.cn&gt;
Cc: Haavard Skinnemoen &lt;hskinnemoen@gmail.com&gt;
Cc: Hans-Christian Egtvedt &lt;egtvedt@samfundet.no&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Helge Deller &lt;deller@gmx.de&gt;
Cc: Hirokazu Takata &lt;takata@linux-m32r.org&gt;
Cc: Ivan Kokshaysky &lt;ink@jurassic.park.msu.ru&gt;
Cc: James E.J. Bottomley &lt;jejb@parisc-linux.org&gt;
Cc: James Hogan &lt;james.hogan@imgtec.com&gt;
Cc: Jason Wang &lt;jasowang@redhat.com&gt;
Cc: Jesper Nilsson &lt;jesper.nilsson@axis.com&gt;
Cc: Joe Perches &lt;joe@perches.com&gt;
Cc: Jonas Bonn &lt;jonas@southpole.se&gt;
Cc: Joseph Myers &lt;joseph@codesourcery.com&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Koichi Yasutake &lt;yasutake.koichi@jp.panasonic.com&gt;
Cc: Lennox Wu &lt;lennox.wu@gmail.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Mark Salter &lt;msalter@redhat.com&gt;
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Cc: Matt Turner &lt;mattst88@gmail.com&gt;
Cc: Max Filippov &lt;jcmvbkbc@gmail.com&gt;
Cc: Michael Neuling &lt;mikey@neuling.org&gt;
Cc: Michal Simek &lt;monstr@monstr.eu&gt;
Cc: Mikael Starvik &lt;starvik@axis.com&gt;
Cc: Nicolas Pitre &lt;nico@linaro.org&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Paul Burton &lt;paul.burton@imgtec.com&gt;
Cc: Paul E. McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
Cc: Paul Gortmaker &lt;paul.gortmaker@windriver.com&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Qais Yousef &lt;qais.yousef@imgtec.com&gt;
Cc: Qiaowei Ren &lt;qiaowei.ren@intel.com&gt;
Cc: Rafael Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Richard Henderson &lt;rth@twiddle.net&gt;
Cc: Richard Kuo &lt;rkuo@codeaurora.org&gt;
Cc: Russell King &lt;linux@arm.linux.org.uk&gt;
Cc: Steven Miao &lt;realmz6@gmail.com&gt;
Cc: Steven Rostedt &lt;srostedt@redhat.com&gt;
Cc: Stratos Karafotis &lt;stratosk@semaphore.gr&gt;
Cc: Tim Chen &lt;tim.c.chen@linux.intel.com&gt;
Cc: Tony Luck &lt;tony.luck@intel.com&gt;
Cc: Vasily Kulikov &lt;segoon@openwall.com&gt;
Cc: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Cc: Vineet Gupta &lt;Vineet.Gupta1@synopsys.com&gt;
Cc: Waiman Long &lt;Waiman.Long@hp.com&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: Wolfram Sang &lt;wsa@the-dreams.de&gt;
Cc: adi-buildroot-devel@lists.sourceforge.net
Cc: linux390@de.ibm.com
Cc: linux-alpha@vger.kernel.org
Cc: linux-am33-list@redhat.com
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-c6x-dev@linux-c6x.org
Cc: linux-cris-kernel@axis.com
Cc: linux-hexagon@vger.kernel.org
Cc: linux-ia64@vger.kernel.org
Cc: linux@lists.openrisc.net
Cc: linux-m32r-ja@ml.linux-m32r.org
Cc: linux-m32r@ml.linux-m32r.org
Cc: linux-m68k@lists.linux-m68k.org
Cc: linux-metag@vger.kernel.org
Cc: linux-mips@linux-mips.org
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: linux-xtensa@linux-xtensa.org
Cc: sparclinux@vger.kernel.org
Link: http://lkml.kernel.org/r/1404079773.2619.4.camel@buesod1.americas.hpqcorp.net
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The arch_mutex_cpu_relax() function, introduced by 34b133f, is
hacky and ugly. It was added a few years ago to address the fact
that common cpu_relax() calls include yielding on s390, and thus
impact the optimistic spinning functionality of mutexes. Nowadays
we use this function well beyond mutexes: rwsem, qrwlock, mcs and
lockref. Since the macro that defines the call is in the mutex header,
any users must include mutex.h and the naming is misleading as well.

This patch (i) renames the call to cpu_relax_lowlatency  ("relax, but
only if you can do it with very low latency") and (ii) defines it in
each arch's asm/processor.h local header, just like for regular cpu_relax
functions. On all archs, except s390, cpu_relax_lowlatency is simply cpu_relax,
and thus we can take it out of mutex.h. While this can seem redundant,
I believe it is a good choice as it allows us to move out arch specific
logic from generic locking primitives and enables future(?) archs to
transparently define it, similarly to System Z.

Signed-off-by: Davidlohr Bueso &lt;davidlohr@hp.com&gt;
Signed-off-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Anton Blanchard &lt;anton@samba.org&gt;
Cc: Aurelien Jacquiot &lt;a-jacquiot@ti.com&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Bharat Bhushan &lt;r65777@freescale.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Chen Liqin &lt;liqin.linux@gmail.com&gt;
Cc: Chris Metcalf &lt;cmetcalf@tilera.com&gt;
Cc: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Cc: Chris Zankel &lt;chris@zankel.net&gt;
Cc: David Howells &lt;dhowells@redhat.com&gt;
Cc: David S. Miller &lt;davem@davemloft.net&gt;
Cc: Deepthi Dharwar &lt;deepthi@linux.vnet.ibm.com&gt;
Cc: Dominik Dingel &lt;dingel@linux.vnet.ibm.com&gt;
Cc: Fenghua Yu &lt;fenghua.yu@intel.com&gt;
Cc: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Cc: Guan Xuetao &lt;gxt@mprc.pku.edu.cn&gt;
Cc: Haavard Skinnemoen &lt;hskinnemoen@gmail.com&gt;
Cc: Hans-Christian Egtvedt &lt;egtvedt@samfundet.no&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Helge Deller &lt;deller@gmx.de&gt;
Cc: Hirokazu Takata &lt;takata@linux-m32r.org&gt;
Cc: Ivan Kokshaysky &lt;ink@jurassic.park.msu.ru&gt;
Cc: James E.J. Bottomley &lt;jejb@parisc-linux.org&gt;
Cc: James Hogan &lt;james.hogan@imgtec.com&gt;
Cc: Jason Wang &lt;jasowang@redhat.com&gt;
Cc: Jesper Nilsson &lt;jesper.nilsson@axis.com&gt;
Cc: Joe Perches &lt;joe@perches.com&gt;
Cc: Jonas Bonn &lt;jonas@southpole.se&gt;
Cc: Joseph Myers &lt;joseph@codesourcery.com&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Koichi Yasutake &lt;yasutake.koichi@jp.panasonic.com&gt;
Cc: Lennox Wu &lt;lennox.wu@gmail.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Mark Salter &lt;msalter@redhat.com&gt;
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Cc: Matt Turner &lt;mattst88@gmail.com&gt;
Cc: Max Filippov &lt;jcmvbkbc@gmail.com&gt;
Cc: Michael Neuling &lt;mikey@neuling.org&gt;
Cc: Michal Simek &lt;monstr@monstr.eu&gt;
Cc: Mikael Starvik &lt;starvik@axis.com&gt;
Cc: Nicolas Pitre &lt;nico@linaro.org&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Paul Burton &lt;paul.burton@imgtec.com&gt;
Cc: Paul E. McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
Cc: Paul Gortmaker &lt;paul.gortmaker@windriver.com&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Qais Yousef &lt;qais.yousef@imgtec.com&gt;
Cc: Qiaowei Ren &lt;qiaowei.ren@intel.com&gt;
Cc: Rafael Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Richard Henderson &lt;rth@twiddle.net&gt;
Cc: Richard Kuo &lt;rkuo@codeaurora.org&gt;
Cc: Russell King &lt;linux@arm.linux.org.uk&gt;
Cc: Steven Miao &lt;realmz6@gmail.com&gt;
Cc: Steven Rostedt &lt;srostedt@redhat.com&gt;
Cc: Stratos Karafotis &lt;stratosk@semaphore.gr&gt;
Cc: Tim Chen &lt;tim.c.chen@linux.intel.com&gt;
Cc: Tony Luck &lt;tony.luck@intel.com&gt;
Cc: Vasily Kulikov &lt;segoon@openwall.com&gt;
Cc: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Cc: Vineet Gupta &lt;Vineet.Gupta1@synopsys.com&gt;
Cc: Waiman Long &lt;Waiman.Long@hp.com&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: Wolfram Sang &lt;wsa@the-dreams.de&gt;
Cc: adi-buildroot-devel@lists.sourceforge.net
Cc: linux390@de.ibm.com
Cc: linux-alpha@vger.kernel.org
Cc: linux-am33-list@redhat.com
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-c6x-dev@linux-c6x.org
Cc: linux-cris-kernel@axis.com
Cc: linux-hexagon@vger.kernel.org
Cc: linux-ia64@vger.kernel.org
Cc: linux@lists.openrisc.net
Cc: linux-m32r-ja@ml.linux-m32r.org
Cc: linux-m32r@ml.linux-m32r.org
Cc: linux-m68k@lists.linux-m68k.org
Cc: linux-metag@vger.kernel.org
Cc: linux-mips@linux-mips.org
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: linux-xtensa@linux-xtensa.org
Cc: sparclinux@vger.kernel.org
Link: http://lkml.kernel.org/r/1404079773.2619.4.camel@buesod1.americas.hpqcorp.net
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>nmi: provide the option to issue an NMI back trace to every cpu but current</title>
<updated>2014-06-23T23:47:44+00:00</updated>
<author>
<name>Aaron Tomlin</name>
<email>atomlin@redhat.com</email>
</author>
<published>2014-06-23T20:22:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=f3aca3d09525f87731ba6b892c9b010570bc54b4'/>
<id>f3aca3d09525f87731ba6b892c9b010570bc54b4</id>
<content type='text'>
Sometimes it is preferred not to use the trigger_all_cpu_backtrace()
routine when one wants to avoid capturing a back trace for current.  For
instance if one was previously captured recently.

This patch provides a new routine namely
trigger_allbutself_cpu_backtrace() which offers the flexibility to issue
an NMI to every cpu but current and capture a back trace accordingly.

Patch x86 and sparc to support new routine.

[dzickus@redhat.com: add stub in #else clause]
[dzickus@redhat.com: don't print message in single processor case, wrap with get/put_cpu based on Oleg's suggestion]
[sfr@canb.auug.org.au: undo C99ism]
Signed-off-by: Aaron Tomlin &lt;atomlin@redhat.com&gt;
Signed-off-by: Don Zickus &lt;dzickus@redhat.com&gt;
Acked-by: David S. Miller &lt;davem@davemloft.net&gt;
Cc: Mateusz Guzik &lt;mguzik@redhat.com&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Signed-off-by: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Sometimes it is preferred not to use the trigger_all_cpu_backtrace()
routine when one wants to avoid capturing a back trace for current.  For
instance if one was previously captured recently.

This patch provides a new routine namely
trigger_allbutself_cpu_backtrace() which offers the flexibility to issue
an NMI to every cpu but current and capture a back trace accordingly.

Patch x86 and sparc to support new routine.

[dzickus@redhat.com: add stub in #else clause]
[dzickus@redhat.com: don't print message in single processor case, wrap with get/put_cpu based on Oleg's suggestion]
[sfr@canb.auug.org.au: undo C99ism]
Signed-off-by: Aaron Tomlin &lt;atomlin@redhat.com&gt;
Signed-off-by: Don Zickus &lt;dzickus@redhat.com&gt;
Acked-by: David S. Miller &lt;davem@davemloft.net&gt;
Cc: Mateusz Guzik &lt;mguzik@redhat.com&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Signed-off-by: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
