<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch/parisc/include/asm/processor.h, branch v4.11</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge branch 'parisc-4.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux</title>
<updated>2016-12-21T18:47:13+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2016-12-21T18:47:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=0c961c5511fe48834c73215d2203bdac3353dcae'/>
<id>0c961c5511fe48834c73215d2203bdac3353dcae</id>
<content type='text'>
Pull parisc updates from Helge Deller:

 - add Kernel address space layout randomization support

 - re-enable interrupts earlier now that we have a working IRQ stack

 - optimize the timer interrupt function to better cope with missed
   timer irqs

 - fix error return code in parisc perf code (by Dan Carpenter)

 - fix PAT debug code

* 'parisc-4.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Optimize timer interrupt function
  parisc: perf: return -EFAULT on error
  parisc: Enhance CPU detection code on PAT machines
  parisc: Re-enable interrupts early
  parisc: Enable KASLR
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull parisc updates from Helge Deller:

 - add Kernel address space layout randomization support

 - re-enable interrupts earlier now that we have a working IRQ stack

 - optimize the timer interrupt function to better cope with missed
   timer irqs

 - fix error return code in parisc perf code (by Dan Carpenter)

 - fix PAT debug code

* 'parisc-4.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Optimize timer interrupt function
  parisc: perf: return -EFAULT on error
  parisc: Enhance CPU detection code on PAT machines
  parisc: Re-enable interrupts early
  parisc: Enable KASLR
</pre>
</div>
</content>
</entry>
<entry>
<title>parisc: Optimize timer interrupt function</title>
<updated>2016-12-20T20:39:40+00:00</updated>
<author>
<name>Helge Deller</name>
<email>deller@gmx.de</email>
</author>
<published>2016-12-20T19:51:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=160494d381373cfa21208484aea4e5db2d3cb0a8'/>
<id>160494d381373cfa21208484aea4e5db2d3cb0a8</id>
<content type='text'>
Restructure the timer interrupt function to better cope with missed timer irqs.
Optimize the calculation when the next interrupt should happen and skip irqs if
they would happen too shortly after exit of the irq function.

The update_process_times() call is done anyway at every timer irq, so we can
safely drop the prof_counter and prof_multiplier variables from the per_cpu
structure.

Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Restructure the timer interrupt function to better cope with missed timer irqs.
Optimize the calculation when the next interrupt should happen and skip irqs if
they would happen too shortly after exit of the irq function.

The update_process_times() call is done anyway at every timer irq, so we can
safely drop the prof_counter and prof_multiplier variables from the per_cpu
structure.

Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>locking/core: Provide common cpu_relax_yield() definition</title>
<updated>2016-11-17T07:17:36+00:00</updated>
<author>
<name>Christian Borntraeger</name>
<email>borntraeger@de.ibm.com</email>
</author>
<published>2016-11-16T12:23:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=6d0d287891a022ebba572327cbd70b5de69a63a2'/>
<id>6d0d287891a022ebba572327cbd70b5de69a63a2</id>
<content type='text'>
No need to duplicate the same define everywhere. Since
the only user is stop-machine and the only provider is
s390, we can use a default implementation of cpu_relax_yield()
in sched.h.

Suggested-by: Russell King &lt;rmk+kernel@armlinux.org.uk&gt;
Signed-off-by: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Reviewed-by: David Hildenbrand &lt;david@redhat.com&gt;
Acked-by: Russell King &lt;rmk+kernel@armlinux.org.uk&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Cc: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Cc: Noam Camus &lt;noamc@ezchip.com&gt;
Cc: Paul E. McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: kvm@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-s390 &lt;linux-s390@vger.kernel.org&gt;
Cc: linuxppc-dev@lists.ozlabs.org
Cc: sparclinux@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1479298985-191589-1-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
No need to duplicate the same define everywhere. Since
the only user is stop-machine and the only provider is
s390, we can use a default implementation of cpu_relax_yield()
in sched.h.

Suggested-by: Russell King &lt;rmk+kernel@armlinux.org.uk&gt;
Signed-off-by: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Reviewed-by: David Hildenbrand &lt;david@redhat.com&gt;
Acked-by: Russell King &lt;rmk+kernel@armlinux.org.uk&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Cc: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Cc: Noam Camus &lt;noamc@ezchip.com&gt;
Cc: Paul E. McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: kvm@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-s390 &lt;linux-s390@vger.kernel.org&gt;
Cc: linuxppc-dev@lists.ozlabs.org
Cc: sparclinux@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1479298985-191589-1-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>locking/core, arch: Remove cpu_relax_lowlatency()</title>
<updated>2016-11-16T09:15:11+00:00</updated>
<author>
<name>Christian Borntraeger</name>
<email>borntraeger@de.ibm.com</email>
</author>
<published>2016-10-25T09:03:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=5bd0b85ba8bb9de6f61f33f3752fc85f4c87fc22'/>
<id>5bd0b85ba8bb9de6f61f33f3752fc85f4c87fc22</id>
<content type='text'>
As there are no users left, we can remove cpu_relax_lowlatency()
implementations from every architecture.

Signed-off-by: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Cc: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Cc: Noam Camus &lt;noamc@ezchip.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: linuxppc-dev@lists.ozlabs.org
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Cc: &lt;linux-arch@vger.kernel.org&gt;
Link: http://lkml.kernel.org/r/1477386195-32736-6-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
As there are no users left, we can remove cpu_relax_lowlatency()
implementations from every architecture.

Signed-off-by: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Cc: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Cc: Noam Camus &lt;noamc@ezchip.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: linuxppc-dev@lists.ozlabs.org
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Cc: &lt;linux-arch@vger.kernel.org&gt;
Link: http://lkml.kernel.org/r/1477386195-32736-6-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>locking/core: Introduce cpu_relax_yield()</title>
<updated>2016-11-16T09:15:09+00:00</updated>
<author>
<name>Christian Borntraeger</name>
<email>borntraeger@de.ibm.com</email>
</author>
<published>2016-10-25T09:03:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=79ab11cdb90d8536817ab7357ecb6b1ff76be26c'/>
<id>79ab11cdb90d8536817ab7357ecb6b1ff76be26c</id>
<content type='text'>
For spinning loops people do often use barrier() or cpu_relax().
For most architectures cpu_relax and barrier are the same, but on
some architectures cpu_relax can add some latency.
For example on power,sparc64 and arc, cpu_relax can shift the CPU
towards other hardware threads in an SMT environment.
On s390 cpu_relax does even more, it uses an hypercall to the
hypervisor to give up the timeslice.
In contrast to the SMT yielding this can result in larger latencies.
In some places this latency is unwanted, so another variant
"cpu_relax_lowlatency" was introduced. Before this is used in more
and more places, lets revert the logic and provide a cpu_relax_yield
that can be called in places where yielding is more important than
latency. By default this is the same as cpu_relax on all architectures.

Signed-off-by: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Cc: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Cc: Noam Camus &lt;noamc@ezchip.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: linuxppc-dev@lists.ozlabs.org
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1477386195-32736-2-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
For spinning loops people do often use barrier() or cpu_relax().
For most architectures cpu_relax and barrier are the same, but on
some architectures cpu_relax can add some latency.
For example on power,sparc64 and arc, cpu_relax can shift the CPU
towards other hardware threads in an SMT environment.
On s390 cpu_relax does even more, it uses an hypercall to the
hypervisor to give up the timeslice.
In contrast to the SMT yielding this can result in larger latencies.
In some places this latency is unwanted, so another variant
"cpu_relax_lowlatency" was introduced. Before this is used in more
and more places, lets revert the logic and provide a cpu_relax_yield
that can be called in places where yielding is more important than
latency. By default this is the same as cpu_relax on all architectures.

Signed-off-by: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Cc: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Cc: Noam Camus &lt;noamc@ezchip.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: linuxppc-dev@lists.ozlabs.org
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1477386195-32736-2-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>parisc: Reduce overhead of parisc_requires_coherency()</title>
<updated>2016-01-12T21:03:36+00:00</updated>
<author>
<name>Helge Deller</name>
<email>deller@gmx.de</email>
</author>
<published>2015-12-12T17:22:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=fc6325750348272d10a8e39adb9fc0e89a667774'/>
<id>fc6325750348272d10a8e39adb9fc0e89a667774</id>
<content type='text'>
Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>parisc: Drop definition of start_thread_som for HP-UX SOM binaries</title>
<updated>2015-11-20T09:19:19+00:00</updated>
<author>
<name>Helge Deller</name>
<email>deller@gmx.de</email>
</author>
<published>2015-11-20T09:12:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=1e208ae7326caa33ef7d4496d7ff1c404657a4a3'/>
<id>1e208ae7326caa33ef7d4496d7ff1c404657a4a3</id>
<content type='text'>
The definition of start_thread_som was planned to be used to execute
HP-UX SOM binaries. Since HP-UX compatibility was dropped with kernel 4.0
there is no need to carry it further.

Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The definition of start_thread_som was planned to be used to execute
HP-UX SOM binaries. Since HP-UX compatibility was dropped with kernel 4.0
there is no need to carry it further.

Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>parisc: hpux - Remove hpux gateway page</title>
<updated>2015-02-16T21:35:06+00:00</updated>
<author>
<name>Helge Deller</name>
<email>deller@gmx.de</email>
</author>
<published>2015-02-16T21:21:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=c78c2b7e0409feed41ba1b5e84bff5d901c9b65f'/>
<id>c78c2b7e0409feed41ba1b5e84bff5d901c9b65f</id>
<content type='text'>
Drop code to create HP-UX gateway page and syscall entry code.

Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Drop code to create HP-UX gateway page and syscall entry code.

Signed-off-by: Helge Deller &lt;deller@gmx.de&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>parisc,metag: Do not hardcode maximum userspace stack size</title>
<updated>2014-05-14T23:01:41+00:00</updated>
<author>
<name>Helge Deller</name>
<email>deller@gmx.de</email>
</author>
<published>2014-04-30T21:26:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=042d27acb64924a0e8a43e972485913a32407beb'/>
<id>042d27acb64924a0e8a43e972485913a32407beb</id>
<content type='text'>
This patch affects only architectures where the stack grows upwards
(currently parisc and metag only). On those do not hardcode the maximum
initial stack size to 1GB for 32-bit processes, but make it configurable
via a config option.

The main problem with the hardcoded stack size is, that we have two
memory regions which grow upwards: stack and heap. To keep most of the
memory available for heap in a flexmap memory layout, it makes no sense
to hard allocate up to 1GB of the memory for stack which can't be used
as heap then.

This patch makes the stack size for 32-bit processes configurable and
uses 80MB as default value which has been in use during the last few
years on parisc and which hasn't showed any problems yet.

Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
Signed-off-by: James Hogan &lt;james.hogan@imgtec.com&gt;
Cc: "James E.J. Bottomley" &lt;jejb@parisc-linux.org&gt;
Cc: linux-parisc@vger.kernel.org
Cc: linux-metag@vger.kernel.org
Cc: John David Anglin &lt;dave.anglin@bell.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This patch affects only architectures where the stack grows upwards
(currently parisc and metag only). On those do not hardcode the maximum
initial stack size to 1GB for 32-bit processes, but make it configurable
via a config option.

The main problem with the hardcoded stack size is, that we have two
memory regions which grow upwards: stack and heap. To keep most of the
memory available for heap in a flexmap memory layout, it makes no sense
to hard allocate up to 1GB of the memory for stack which can't be used
as heap then.

This patch makes the stack size for 32-bit processes configurable and
uses 80MB as default value which has been in use during the last few
years on parisc and which hasn't showed any problems yet.

Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
Signed-off-by: James Hogan &lt;james.hogan@imgtec.com&gt;
Cc: "James E.J. Bottomley" &lt;jejb@parisc-linux.org&gt;
Cc: linux-parisc@vger.kernel.org
Cc: linux-metag@vger.kernel.org
Cc: John David Anglin &lt;dave.anglin@bell.net&gt;
</pre>
</div>
</content>
</entry>
</feed>
