<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/arch/x86/kernel/tsc_sync.c, branch v3.2.36</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>locking: Convert __raw_spin* functions to arch_spin*</title>
<updated>2009-12-14T22:55:32+00:00</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2009-12-02T19:01:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=0199c4e68d1f02894bdefe4b5d9e9ee4aedd8d62'/>
<id>0199c4e68d1f02894bdefe4b5d9e9ee4aedd8d62</id>
<content type='text'>
Name space cleanup. No functional change.

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Acked-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Acked-by: David S. Miller &lt;davem@davemloft.net&gt;
Acked-by: Ingo Molnar &lt;mingo@elte.hu&gt;
Cc: linux-arch@vger.kernel.org
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Name space cleanup. No functional change.

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Acked-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Acked-by: David S. Miller &lt;davem@davemloft.net&gt;
Acked-by: Ingo Molnar &lt;mingo@elte.hu&gt;
Cc: linux-arch@vger.kernel.org
</pre>
</div>
</content>
</entry>
<entry>
<title>locking: Rename __RAW_SPIN_LOCK_UNLOCKED to __ARCH_SPIN_LOCK_UNLOCKED</title>
<updated>2009-12-14T22:55:32+00:00</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2009-12-03T11:38:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=edc35bd72e2079b25f99c5da7d7a65dbbffc4a26'/>
<id>edc35bd72e2079b25f99c5da7d7a65dbbffc4a26</id>
<content type='text'>
Further name space cleanup. No functional change

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Acked-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Acked-by: David S. Miller &lt;davem@davemloft.net&gt;
Acked-by: Ingo Molnar &lt;mingo@elte.hu&gt;
Cc: linux-arch@vger.kernel.org
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Further name space cleanup. No functional change

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Acked-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Acked-by: David S. Miller &lt;davem@davemloft.net&gt;
Acked-by: Ingo Molnar &lt;mingo@elte.hu&gt;
Cc: linux-arch@vger.kernel.org
</pre>
</div>
</content>
</entry>
<entry>
<title>locking: Convert raw_spinlock to arch_spinlock</title>
<updated>2009-12-14T22:55:32+00:00</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2009-12-02T18:49:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=445c89514be242b1b0080056d50bdc1b72adeb5c'/>
<id>445c89514be242b1b0080056d50bdc1b72adeb5c</id>
<content type='text'>
The raw_spin* namespace was taken by lockdep for the architecture
specific implementations. raw_spin_* would be the ideal name space for
the spinlocks which are not converted to sleeping locks in preempt-rt.

Linus suggested to convert the raw_ to arch_ locks and cleanup the
name space instead of using an artifical name like core_spin,
atomic_spin or whatever

No functional change.

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Acked-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Acked-by: David S. Miller &lt;davem@davemloft.net&gt;
Acked-by: Ingo Molnar &lt;mingo@elte.hu&gt;
Cc: linux-arch@vger.kernel.org

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The raw_spin* namespace was taken by lockdep for the architecture
specific implementations. raw_spin_* would be the ideal name space for
the spinlocks which are not converted to sleeping locks in preempt-rt.

Linus suggested to convert the raw_ to arch_ locks and cleanup the
name space instead of using an artifical name like core_spin,
atomic_spin or whatever

No functional change.

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Acked-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Acked-by: David S. Miller &lt;davem@davemloft.net&gt;
Acked-by: Ingo Molnar &lt;mingo@elte.hu&gt;
Cc: linux-arch@vger.kernel.org

</pre>
</div>
</content>
</entry>
<entry>
<title>x86: Limit number of per cpu TSC sync messages</title>
<updated>2009-11-26T09:17:45+00:00</updated>
<author>
<name>Mike Travis</name>
<email>travis@sgi.com</email>
</author>
<published>2009-11-18T00:22:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=9b3660a55a9052518c91cc7c62d89e22f3f6f490'/>
<id>9b3660a55a9052518c91cc7c62d89e22f3f6f490</id>
<content type='text'>
Limit the number of per cpu TSC sync messages by only printing
to the console if an error occurs, otherwise print as a DEBUG
message.

The info message "Skipping synchronization ..." is only printed
after the last cpu has booted.

Signed-off-by: Mike Travis &lt;travis@sgi.com&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Roland Dreier &lt;rdreier@cisco.com&gt;
Cc: Randy Dunlap &lt;rdunlap@xenotime.net&gt;
Cc: Tejun Heo &lt;tj@kernel.org&gt;
Cc: Andi Kleen &lt;andi@firstfloor.org&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@suse.de&gt;
Cc: Yinghai Lu &lt;yhlu.kernel@gmail.com&gt;
Cc: David Rientjes &lt;rientjes@google.com&gt;
Cc: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Rusty Russell &lt;rusty@rustcorp.com.au&gt;
Cc: Hidetoshi Seto &lt;seto.hidetoshi@jp.fujitsu.com&gt;
Cc: Jack Steiner &lt;steiner@sgi.com&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
LKML-Reference: &lt;20091118002222.181053000@alcatraz.americas.sgi.com&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Limit the number of per cpu TSC sync messages by only printing
to the console if an error occurs, otherwise print as a DEBUG
message.

The info message "Skipping synchronization ..." is only printed
after the last cpu has booted.

Signed-off-by: Mike Travis &lt;travis@sgi.com&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Roland Dreier &lt;rdreier@cisco.com&gt;
Cc: Randy Dunlap &lt;rdunlap@xenotime.net&gt;
Cc: Tejun Heo &lt;tj@kernel.org&gt;
Cc: Andi Kleen &lt;andi@firstfloor.org&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@suse.de&gt;
Cc: Yinghai Lu &lt;yhlu.kernel@gmail.com&gt;
Cc: David Rientjes &lt;rientjes@google.com&gt;
Cc: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Rusty Russell &lt;rusty@rustcorp.com.au&gt;
Cc: Hidetoshi Seto &lt;seto.hidetoshi@jp.fujitsu.com&gt;
Cc: Jack Steiner &lt;steiner@sgi.com&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
LKML-Reference: &lt;20091118002222.181053000@alcatraz.americas.sgi.com&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86: Reduce verbosity of "TSC is reliable" message</title>
<updated>2009-09-24T09:35:19+00:00</updated>
<author>
<name>Roland Dreier</name>
<email>rdreier@cisco.com</email>
</author>
<published>2009-09-23T22:33:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=ea01c0d7315d6e3218fd22a6947c5b09305fcf65'/>
<id>ea01c0d7315d6e3218fd22a6947c5b09305fcf65</id>
<content type='text'>
On modern systems, the kernel prints the message

    Skipping synchronization checks as TSC is reliable.

once for every non-boot CPU.

This gets kind of ridiculous on huge systems; for example, on a
64-thread system I was lucky enough to get:

    $ dmesg | grep 'TSC is reliable' | wc
         63     567    4221

There's no point to doing this for every CPU, since the code is
just checking the boot CPU anyway, so change this to a
printk_once() to make the message appears only once.

Signed-off-by: Roland Dreier &lt;rolandd@cisco.com&gt;
LKML-Reference: &lt;adazl8l2swc.fsf@cisco.com&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
On modern systems, the kernel prints the message

    Skipping synchronization checks as TSC is reliable.

once for every non-boot CPU.

This gets kind of ridiculous on huge systems; for example, on a
64-thread system I was lucky enough to get:

    $ dmesg | grep 'TSC is reliable' | wc
         63     567    4221

There's no point to doing this for every CPU, since the code is
just checking the boot CPU anyway, so change this to a
printk_once() to make the message appears only once.

Signed-off-by: Roland Dreier &lt;rolandd@cisco.com&gt;
LKML-Reference: &lt;adazl8l2swc.fsf@cisco.com&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86: clean up arch/x86/kernel/tsc_sync.c a bit</title>
<updated>2009-05-07T07:32:10+00:00</updated>
<author>
<name>Ingo Molnar</name>
<email>mingo@elte.hu</email>
</author>
<published>2009-05-07T07:12:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=643bec956544d376b7c2a80a3d5c3d0bf94da8d3'/>
<id>643bec956544d376b7c2a80a3d5c3d0bf94da8d3</id>
<content type='text'>
 - remove unused define
 - make the lock variable definition stand out some more
 - convert KERN_* to pr_info() / pr_warning()

[ Impact: cleanup ]

LKML-Reference: &lt;new-submission&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
 - remove unused define
 - make the lock variable definition stand out some more
 - convert KERN_* to pr_info() / pr_warning()

[ Impact: cleanup ]

LKML-Reference: &lt;new-submission&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branches 'x86/apic', 'x86/cleanups', 'x86/cpufeature', 'x86/crashdump', 'x86/debug', 'x86/defconfig', 'x86/detect-hyper', 'x86/doc', 'x86/dumpstack', 'x86/early-printk', 'x86/fpu', 'x86/idle', 'x86/io', 'x86/memory-corruption-check', 'x86/microcode', 'x86/mm', 'x86/mtrr', 'x86/nmi-watchdog', 'x86/pat2', 'x86/pci-ioapic-boot-irq-quirks', 'x86/ptrace', 'x86/quirks', 'x86/reboot', 'x86/setup-memory', 'x86/signal', 'x86/sparse-fixes', 'x86/time', 'x86/uv' and 'x86/xen' into x86/core</title>
<updated>2008-12-23T15:27:23+00:00</updated>
<author>
<name>Ingo Molnar</name>
<email>mingo@elte.hu</email>
</author>
<published>2008-12-23T15:27:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=fa623d1b0222adbe8f822e53c08003b9679a410c'/>
<id>fa623d1b0222adbe8f822e53c08003b9679a410c</id>
<content type='text'>
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
</pre>
</div>
</content>
</entry>
<entry>
<title>x86: add rdtsc barrier to TSC sync check</title>
<updated>2008-11-17T23:15:02+00:00</updated>
<author>
<name>Venki Pallipadi</name>
<email>venkatesh.pallipadi@intel.com</email>
</author>
<published>2008-11-17T22:43:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=93ce99e849433ede4ce8b410b749dc0cad1100b2'/>
<id>93ce99e849433ede4ce8b410b749dc0cad1100b2</id>
<content type='text'>
Impact: fix incorrectly marked unstable TSC clock

Patch (commit 0d12cdd "sched: improve sched_clock() performance") has
a regression on one of the test systems here.

With the patch, I see:

 checking TSC synchronization [CPU#0 -&gt; CPU#1]:
 Measured 28 cycles TSC warp between CPUs, turning off TSC clock.
 Marking TSC unstable due to check_tsc_sync_source failed

Whereas, without the patch syncs pass fine on all CPUs:

 checking TSC synchronization [CPU#0 -&gt; CPU#1]: passed.

Due to this, TSC is marked unstable, when it is not actually unstable.
This is because syncs in check_tsc_wrap() goes away due to this commit.

As per the discussion on this thread, correct way to fix this is to add
explicit syncs as below?

Signed-off-by: Venkatesh Pallipadi &lt;venkatesh.pallipadi@intel.com&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Impact: fix incorrectly marked unstable TSC clock

Patch (commit 0d12cdd "sched: improve sched_clock() performance") has
a regression on one of the test systems here.

With the patch, I see:

 checking TSC synchronization [CPU#0 -&gt; CPU#1]:
 Measured 28 cycles TSC warp between CPUs, turning off TSC clock.
 Marking TSC unstable due to check_tsc_sync_source failed

Whereas, without the patch syncs pass fine on all CPUs:

 checking TSC synchronization [CPU#0 -&gt; CPU#1]: passed.

Due to this, TSC is marked unstable, when it is not actually unstable.
This is because syncs in check_tsc_wrap() goes away due to this commit.

As per the discussion on this thread, correct way to fix this is to add
explicit syncs as below?

Signed-off-by: Venkatesh Pallipadi &lt;venkatesh.pallipadi@intel.com&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86: Add a synthetic TSC_RELIABLE feature bit.</title>
<updated>2008-11-02T01:58:01+00:00</updated>
<author>
<name>Alok Kataria</name>
<email>akataria@vmware.com</email>
</author>
<published>2008-10-31T19:01:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=eca0cd028bdf0f6aaceb0d023e9c7501079a7dda'/>
<id>eca0cd028bdf0f6aaceb0d023e9c7501079a7dda</id>
<content type='text'>
Impact: Changes timebase calibration on Vmware.

Use the synthetic TSC_RELIABLE bit to workaround virtualization anomalies.

Virtual TSCs can be kept nearly in sync, but because the virtual TSC
offset is set by software, it's not perfect.  So, the TSC
synchronization test can fail. Even then the TSC can be used as a
clocksource since the VMware platform exports a reliable TSC to the
guest for timekeeping purposes. Use this bit to check if we need to
skip the TSC sync checks.

Along with this also set the CONSTANT_TSC bit when on VMware, since we
still want to use TSC as clocksource on VM running over hardware which
has unsynchronized TSC's (opteron's), since the hypervisor will take
care of providing consistent TSC to the guest.

Signed-off-by: Alok N Kataria &lt;akataria@vmware.com&gt;
Signed-off-by: Dan Hecht &lt;dhecht@vmware.com&gt;
Signed-off-by: H. Peter Anvin &lt;hpa@zytor.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Impact: Changes timebase calibration on Vmware.

Use the synthetic TSC_RELIABLE bit to workaround virtualization anomalies.

Virtual TSCs can be kept nearly in sync, but because the virtual TSC
offset is set by software, it's not perfect.  So, the TSC
synchronization test can fail. Even then the TSC can be used as a
clocksource since the VMware platform exports a reliable TSC to the
guest for timekeeping purposes. Use this bit to check if we need to
skip the TSC sync checks.

Along with this also set the CONSTANT_TSC bit when on VMware, since we
still want to use TSC as clocksource on VM running over hardware which
has unsynchronized TSC's (opteron's), since the hypervisor will take
care of providing consistent TSC to the guest.

Signed-off-by: Alok N Kataria &lt;akataria@vmware.com&gt;
Signed-off-by: Dan Hecht &lt;dhecht@vmware.com&gt;
Signed-off-by: H. Peter Anvin &lt;hpa@zytor.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86: use WARN() in arch/x86/kernel</title>
<updated>2008-08-21T08:01:52+00:00</updated>
<author>
<name>Arjan van de Ven</name>
<email>arjan@linux.intel.com</email>
</author>
<published>2008-07-08T16:51:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=bde78a79a6eb015f33aa4660df1b06f5135def20'/>
<id>bde78a79a6eb015f33aa4660df1b06f5135def20</id>
<content type='text'>
Use WARN() instead of a printk+WARN_ON() pair; this way the message
becomes part of the warning section for better reporting/collection.
This also allowed the folding of some if()'s into the WARN()

Signed-off-by: Arjan van de Ven &lt;arjan@linux.intel.com&gt;
Cc: akpm@linux-foundation.org
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Use WARN() instead of a printk+WARN_ON() pair; this way the message
becomes part of the warning section for better reporting/collection.
This also allowed the folding of some if()'s into the WARN()

Signed-off-by: Arjan van de Ven &lt;arjan@linux.intel.com&gt;
Cc: akpm@linux-foundation.org
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</pre>
</div>
</content>
</entry>
</feed>
