<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/arch, branch v3.2.13</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>powerpc/pmac: Fix SMP kernels on pre-core99 UP machines</title>
<updated>2012-03-23T18:21:23+00:00</updated>
<author>
<name>Benjamin Herrenschmidt</name>
<email>benh@kernel.crashing.org</email>
</author>
<published>2011-12-09T04:06:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8d7548704a1a6b6dacd6b458897007de80a820b3'/>
<id>8d7548704a1a6b6dacd6b458897007de80a820b3</id>
<content type='text'>
commit 78c5c68a4cf4329d17abfa469345ddf323d4fd62 upstream.

The code for "powersurge" SMP would kick in and cause a crash
at boot due to the lack of a NULL test.

Signed-off-by: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Signed-off-by: Jeremy Kerr &lt;jeremy.kerr@canonical.com&gt;
Reported-by: Adam Conrad &lt;adconrad@ubuntu.com&gt;
Tested-by: Adam Conrad &lt;adconrad@ubuntu.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 78c5c68a4cf4329d17abfa469345ddf323d4fd62 upstream.

The code for "powersurge" SMP would kick in and cause a crash
at boot due to the lack of a NULL test.

Signed-off-by: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Signed-off-by: Jeremy Kerr &lt;jeremy.kerr@canonical.com&gt;
Reported-by: Adam Conrad &lt;adconrad@ubuntu.com&gt;
Tested-by: Adam Conrad &lt;adconrad@ubuntu.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>sparc32: Add -Av8 to assembler command line.</title>
<updated>2012-03-19T16:02:34+00:00</updated>
<author>
<name>David S. Miller</name>
<email>davem@davemloft.net</email>
</author>
<published>2012-03-14T01:19:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=60eba3f83735efbb3125708a37542a2c93123fea'/>
<id>60eba3f83735efbb3125708a37542a2c93123fea</id>
<content type='text'>
commit e0adb9902fb338a9fe634c3c2a3e474075c733ba upstream.

Newer version of binutils are more strict about specifying the
correct options to enable certain classes of instructions.

The sparc32 build is done for v7 in order to support sun4c systems
which lack hardware integer multiply and divide instructions.

So we have to pass -Av8 when building the assembler routines that
use these instructions and get patched into the kernel when we find
out that we have a v8 capable cpu.

Reported-by: Paul Gortmaker &lt;paul.gortmaker@windriver.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit e0adb9902fb338a9fe634c3c2a3e474075c733ba upstream.

Newer version of binutils are more strict about specifying the
correct options to enable certain classes of instructions.

The sparc32 build is done for v7 in order to support sun4c systems
which lack hardware integer multiply and divide instructions.

So we have to pass -Av8 when building the assembler routines that
use these instructions and get patched into the kernel when we find
out that we have a v8 capable cpu.

Reported-by: Paul Gortmaker &lt;paul.gortmaker@windriver.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>perf/x86: Fix local vs remote memory events for NHM/WSM</title>
<updated>2012-03-19T16:02:20+00:00</updated>
<author>
<name>Peter Zijlstra</name>
<email>a.p.zijlstra@chello.nl</email>
</author>
<published>2012-03-05T22:59:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=7dfe63e95b900ebe5d328225f7b02c38d6c21832'/>
<id>7dfe63e95b900ebe5d328225f7b02c38d6c21832</id>
<content type='text'>
commit 87e24f4b67e68d9fd8df16e0bf9c66d1ad2a2533 upstream.

Verified using the below proglet.. before:

[root@westmere ~]# perf stat -e node-stores -e node-store-misses ./numa 0
remote write

 Performance counter stats for './numa 0':

         2,101,554 node-stores
         2,096,931 node-store-misses

       5.021546079 seconds time elapsed

[root@westmere ~]# perf stat -e node-stores -e node-store-misses ./numa 1
local write

 Performance counter stats for './numa 1':

           501,137 node-stores
               199 node-store-misses

       5.124451068 seconds time elapsed

After:

[root@westmere ~]# perf stat -e node-stores -e node-store-misses ./numa 0
remote write

 Performance counter stats for './numa 0':

         2,107,516 node-stores
         2,097,187 node-store-misses

       5.012755149 seconds time elapsed

[root@westmere ~]# perf stat -e node-stores -e node-store-misses ./numa 1
local write

 Performance counter stats for './numa 1':

         2,063,355 node-stores
               165 node-store-misses

       5.082091494 seconds time elapsed

#define _GNU_SOURCE

#include &lt;sched.h&gt;
#include &lt;stdio.h&gt;
#include &lt;errno.h&gt;
#include &lt;sys/mman.h&gt;
#include &lt;sys/types.h&gt;
#include &lt;dirent.h&gt;
#include &lt;signal.h&gt;
#include &lt;unistd.h&gt;
#include &lt;numaif.h&gt;
#include &lt;stdlib.h&gt;

#define SIZE (32*1024*1024)

volatile int done;

void sig_done(int sig)
{
	done = 1;
}

int main(int argc, char **argv)
{
	cpu_set_t *mask, *mask2;
	size_t size;
	int i, err, t;
	int nrcpus = 1024;
	char *mem;
	unsigned long nodemask = 0x01; /* node 0 */
	DIR *node;
	struct dirent *de;
	int read = 0;
	int local = 0;

	if (argc &lt; 2) {
		printf("usage: %s [0-3]\n", argv[0]);
		printf("  bit0 - local/remote\n");
		printf("  bit1 - read/write\n");
		exit(0);
	}

	switch (atoi(argv[1])) {
	case 0:
		printf("remote write\n");
		break;
	case 1:
		printf("local write\n");
		local = 1;
		break;
	case 2:
		printf("remote read\n");
		read = 1;
		break;
	case 3:
		printf("local read\n");
		local = 1;
		read = 1;
		break;
	}

	mask = CPU_ALLOC(nrcpus);
	size = CPU_ALLOC_SIZE(nrcpus);
	CPU_ZERO_S(size, mask);

	node = opendir("/sys/devices/system/node/node0/");
	if (!node)
		perror("opendir");
	while ((de = readdir(node))) {
		int cpu;

		if (sscanf(de-&gt;d_name, "cpu%d", &amp;cpu) == 1)
			CPU_SET_S(cpu, size, mask);
	}
	closedir(node);

	mask2 = CPU_ALLOC(nrcpus);
	CPU_ZERO_S(size, mask2);
	for (i = 0; i &lt; size; i++)
		CPU_SET_S(i, size, mask2);
	CPU_XOR_S(size, mask2, mask2, mask); // invert

	if (!local)
		mask = mask2;

	err = sched_setaffinity(0, size, mask);
	if (err)
		perror("sched_setaffinity");

	mem = mmap(0, SIZE, PROT_READ|PROT_WRITE,
			MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
	err = mbind(mem, SIZE, MPOL_BIND, &amp;nodemask, 8*sizeof(nodemask), MPOL_MF_MOVE);
	if (err)
		perror("mbind");

	signal(SIGALRM, sig_done);
	alarm(5);

	if (!read) {
		while (!done) {
			for (i = 0; i &lt; SIZE; i++)
				mem[i] = 0x01;
		}
	} else {
		while (!done) {
			for (i = 0; i &lt; SIZE; i++)
				t += *(volatile char *)(mem + i);
		}
	}

	return 0;
}

Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Link: http://lkml.kernel.org/n/tip-tq73sxus35xmqpojf7ootxgs@git.kernel.org
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 87e24f4b67e68d9fd8df16e0bf9c66d1ad2a2533 upstream.

Verified using the below proglet.. before:

[root@westmere ~]# perf stat -e node-stores -e node-store-misses ./numa 0
remote write

 Performance counter stats for './numa 0':

         2,101,554 node-stores
         2,096,931 node-store-misses

       5.021546079 seconds time elapsed

[root@westmere ~]# perf stat -e node-stores -e node-store-misses ./numa 1
local write

 Performance counter stats for './numa 1':

           501,137 node-stores
               199 node-store-misses

       5.124451068 seconds time elapsed

After:

[root@westmere ~]# perf stat -e node-stores -e node-store-misses ./numa 0
remote write

 Performance counter stats for './numa 0':

         2,107,516 node-stores
         2,097,187 node-store-misses

       5.012755149 seconds time elapsed

[root@westmere ~]# perf stat -e node-stores -e node-store-misses ./numa 1
local write

 Performance counter stats for './numa 1':

         2,063,355 node-stores
               165 node-store-misses

       5.082091494 seconds time elapsed

#define _GNU_SOURCE

#include &lt;sched.h&gt;
#include &lt;stdio.h&gt;
#include &lt;errno.h&gt;
#include &lt;sys/mman.h&gt;
#include &lt;sys/types.h&gt;
#include &lt;dirent.h&gt;
#include &lt;signal.h&gt;
#include &lt;unistd.h&gt;
#include &lt;numaif.h&gt;
#include &lt;stdlib.h&gt;

#define SIZE (32*1024*1024)

volatile int done;

void sig_done(int sig)
{
	done = 1;
}

int main(int argc, char **argv)
{
	cpu_set_t *mask, *mask2;
	size_t size;
	int i, err, t;
	int nrcpus = 1024;
	char *mem;
	unsigned long nodemask = 0x01; /* node 0 */
	DIR *node;
	struct dirent *de;
	int read = 0;
	int local = 0;

	if (argc &lt; 2) {
		printf("usage: %s [0-3]\n", argv[0]);
		printf("  bit0 - local/remote\n");
		printf("  bit1 - read/write\n");
		exit(0);
	}

	switch (atoi(argv[1])) {
	case 0:
		printf("remote write\n");
		break;
	case 1:
		printf("local write\n");
		local = 1;
		break;
	case 2:
		printf("remote read\n");
		read = 1;
		break;
	case 3:
		printf("local read\n");
		local = 1;
		read = 1;
		break;
	}

	mask = CPU_ALLOC(nrcpus);
	size = CPU_ALLOC_SIZE(nrcpus);
	CPU_ZERO_S(size, mask);

	node = opendir("/sys/devices/system/node/node0/");
	if (!node)
		perror("opendir");
	while ((de = readdir(node))) {
		int cpu;

		if (sscanf(de-&gt;d_name, "cpu%d", &amp;cpu) == 1)
			CPU_SET_S(cpu, size, mask);
	}
	closedir(node);

	mask2 = CPU_ALLOC(nrcpus);
	CPU_ZERO_S(size, mask2);
	for (i = 0; i &lt; size; i++)
		CPU_SET_S(i, size, mask2);
	CPU_XOR_S(size, mask2, mask2, mask); // invert

	if (!local)
		mask = mask2;

	err = sched_setaffinity(0, size, mask);
	if (err)
		perror("sched_setaffinity");

	mem = mmap(0, SIZE, PROT_READ|PROT_WRITE,
			MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
	err = mbind(mem, SIZE, MPOL_BIND, &amp;nodemask, 8*sizeof(nodemask), MPOL_MF_MOVE);
	if (err)
		perror("mbind");

	signal(SIGALRM, sig_done);
	alarm(5);

	if (!read) {
		while (!done) {
			for (i = 0; i &lt; SIZE; i++)
				mem[i] = 0x01;
		}
	} else {
		while (!done) {
			for (i = 0; i &lt; SIZE; i++)
				t += *(volatile char *)(mem + i);
		}
	}

	return 0;
}

Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Link: http://lkml.kernel.org/n/tip-tq73sxus35xmqpojf7ootxgs@git.kernel.org
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>x86: Derandom delay_tsc for 64 bit</title>
<updated>2012-03-19T16:02:19+00:00</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2012-03-09T19:55:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=c042d55ecd82863d6d159e24187c3a1ea45ed669'/>
<id>c042d55ecd82863d6d159e24187c3a1ea45ed669</id>
<content type='text'>
commit a7f4255f906f60f72e00aad2fb000939449ff32e upstream.

Commit f0fbf0abc093 ("x86: integrate delay functions") converted
delay_tsc() into a random delay generator for 64 bit.  The reason is
that it merged the mostly identical versions of delay_32.c and
delay_64.c.  Though the subtle difference of the result was:

 static void delay_tsc(unsigned long loops)
 {
-	unsigned bclock, now;
+	unsigned long bclock, now;

Now the function uses rdtscl() which returns the lower 32bit of the
TSC. On 32bit that's not problematic as unsigned long is 32bit. On 64
bit this fails when the lower 32bit are close to wrap around when
bclock is read, because the following check

       if ((now - bclock) &gt;= loops)
       	  	break;

evaluated to true on 64bit for e.g. bclock = 0xffffffff and now = 0
because the unsigned long (now - bclock) of these values results in
0xffffffff00000001 which is definitely larger than the loops
value. That explains Tvortkos observation:

"Because I am seeing udelay(500) (_occasionally_) being short, and
 that by delaying for some duration between 0us (yep) and 491us."

Make those variables explicitely u32 again, so this works for both 32
and 64 bit.

Reported-by: Tvrtko Ursulin &lt;tvrtko.ursulin@onelan.co.uk&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit a7f4255f906f60f72e00aad2fb000939449ff32e upstream.

Commit f0fbf0abc093 ("x86: integrate delay functions") converted
delay_tsc() into a random delay generator for 64 bit.  The reason is
that it merged the mostly identical versions of delay_32.c and
delay_64.c.  Though the subtle difference of the result was:

 static void delay_tsc(unsigned long loops)
 {
-	unsigned bclock, now;
+	unsigned long bclock, now;

Now the function uses rdtscl() which returns the lower 32bit of the
TSC. On 32bit that's not problematic as unsigned long is 32bit. On 64
bit this fails when the lower 32bit are close to wrap around when
bclock is read, because the following check

       if ((now - bclock) &gt;= loops)
       	  	break;

evaluated to true on 64bit for e.g. bclock = 0xffffffff and now = 0
because the unsigned long (now - bclock) of these values results in
0xffffffff00000001 which is definitely larger than the loops
value. That explains Tvortkos observation:

"Because I am seeing udelay(500) (_occasionally_) being short, and
 that by delaying for some duration between 0us (yep) and 491us."

Make those variables explicitely u32 again, so this works for both 32
and 64 bit.

Reported-by: Tvrtko Ursulin &lt;tvrtko.ursulin@onelan.co.uk&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: OMAP: fix iommu, not mailbox</title>
<updated>2012-03-12T19:31:51+00:00</updated>
<author>
<name>Ohad Ben-Cohen</name>
<email>ohad@wizery.com</email>
</author>
<published>2012-03-04T10:01:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=75d67f37ab959dea9f23953ebda669a93bcfaca1'/>
<id>75d67f37ab959dea9f23953ebda669a93bcfaca1</id>
<content type='text'>
commit 134d12fae0bb8f3d60dc7440a9e1950bb5427167 upstream.

For some weird (freudian?) reason, commit 435792d "ARM: OMAP: make
iommu subsys_initcall to fix builtin omap3isp" unintentionally changed
the mailbox's initcall instead of the iommu's.

Fix that.

Reported-by: Fernando Guzman Lugo &lt;fernando.lugo@ti.com&gt;
Signed-off-by: Ohad Ben-Cohen &lt;ohad@wizery.com&gt;
Cc: Laurent Pinchart &lt;laurent.pinchart@ideasonboard.com&gt;
Cc: Joerg Roedel &lt;Joerg.Roedel@amd.com&gt;
Cc: Tony Lindgren &lt;tony@atomide.com&gt;
Signed-off-by: Joerg Roedel &lt;joerg.roedel@amd.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 134d12fae0bb8f3d60dc7440a9e1950bb5427167 upstream.

For some weird (freudian?) reason, commit 435792d "ARM: OMAP: make
iommu subsys_initcall to fix builtin omap3isp" unintentionally changed
the mailbox's initcall instead of the iommu's.

Fix that.

Reported-by: Fernando Guzman Lugo &lt;fernando.lugo@ti.com&gt;
Signed-off-by: Ohad Ben-Cohen &lt;ohad@wizery.com&gt;
Cc: Laurent Pinchart &lt;laurent.pinchart@ideasonboard.com&gt;
Cc: Joerg Roedel &lt;Joerg.Roedel@amd.com&gt;
Cc: Tony Lindgren &lt;tony@atomide.com&gt;
Signed-off-by: Joerg Roedel &lt;joerg.roedel@amd.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: 7357/1: perf: fix overflow handling for xscale2 PMUs</title>
<updated>2012-03-12T19:31:39+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will.deacon@arm.com</email>
</author>
<published>2012-03-06T16:35:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=261d612b2edcb3e8b00ad990b6b81c71e4a5d108'/>
<id>261d612b2edcb3e8b00ad990b6b81c71e4a5d108</id>
<content type='text'>
commit 3f31ae121348afd9ed39700ea2a63c17cd7eeed1 upstream.

xscale2 PMUs indicate overflow not via the PMU control register, but by
a separate overflow FLAG register instead.

This patch fixes the xscale2 PMU code to use this register to detect
to overflow and ensures that we clear any pending overflow when
disabling a counter.

Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 3f31ae121348afd9ed39700ea2a63c17cd7eeed1 upstream.

xscale2 PMUs indicate overflow not via the PMU control register, but by
a separate overflow FLAG register instead.

This patch fixes the xscale2 PMU code to use this register to detect
to overflow and ensures that we clear any pending overflow when
disabling a counter.

Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: 7356/1: perf: check that we have an event in the PMU IRQ handlers</title>
<updated>2012-03-12T19:31:39+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will.deacon@arm.com</email>
</author>
<published>2012-03-06T16:34:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=288733a6065034d1870b02b164da0fb2d8452178'/>
<id>288733a6065034d1870b02b164da0fb2d8452178</id>
<content type='text'>
commit f6f5a30c834135c9f2fa10400c59ebbdd9188567 upstream.

The PMU IRQ handlers in perf assume that if a counter has overflowed
then perf must be responsible. In the paranoid world of crazy hardware,
this could be false, so check that we do have a valid event before
attempting to dereference NULL in the interrupt path.

Signed-off-by: Ming Lei &lt;tom.leiming@gmail.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit f6f5a30c834135c9f2fa10400c59ebbdd9188567 upstream.

The PMU IRQ handlers in perf assume that if a counter has overflowed
then perf must be responsible. In the paranoid world of crazy hardware,
this could be false, so check that we do have a valid event before
attempting to dereference NULL in the interrupt path.

Signed-off-by: Ming Lei &lt;tom.leiming@gmail.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: 7355/1: perf: clear overflow flag when disabling counter on ARMv7 PMU</title>
<updated>2012-03-12T19:31:38+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will.deacon@arm.com</email>
</author>
<published>2012-03-06T16:34:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=075964ad4370162964f41ba1136b8581ab1a302a'/>
<id>075964ad4370162964f41ba1136b8581ab1a302a</id>
<content type='text'>
commit 99c1745b9c76910e195889044f914b4898b7c9a5 upstream.

When disabling a counter on an ARMv7 PMU, we should also clear the
overflow flag in case an overflow occurred whilst stopping the counter.
This prevents a spurious overflow being picked up later and leading to
either false accounting or a NULL dereference.

Reported-by: Ming Lei &lt;tom.leiming@gmail.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 99c1745b9c76910e195889044f914b4898b7c9a5 upstream.

When disabling a counter on an ARMv7 PMU, we should also clear the
overflow flag in case an overflow occurred whilst stopping the counter.
This prevents a spurious overflow being picked up later and leading to
either false accounting or a NULL dereference.

Reported-by: Ming Lei &lt;tom.leiming@gmail.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: 7354/1: perf: limit sample_period to half max_period in non-sampling mode</title>
<updated>2012-03-12T19:31:38+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will.deacon@arm.com</email>
</author>
<published>2012-03-06T16:33:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=14e84b15bcd96521190c5566c440c56553e66fc9'/>
<id>14e84b15bcd96521190c5566c440c56553e66fc9</id>
<content type='text'>
commit 5727347180ebc6b4a866fcbe00dcb39cc03acb37 upstream.

On ARM, the PMU does not stop counting after an overflow and therefore
IRQ latency affects the new counter value read by the kernel. This is
significant for non-sampling runs where it is possible for the new value
to overtake the previous one, causing the delta to be out by up to
max_period events.

Commit a737823d ("ARM: 6835/1: perf: ensure overflows aren't missed due
to IRQ latency") attempted to fix this problem by allowing interrupt
handlers to pass an overflow flag to the event update function, causing
the overflow calculation to assume that the counter passed through zero
when going from prev to new. Unfortunately, this doesn't work when
overflow occurs on the perf_task_tick path because we have the flag
cleared and end up computing a large negative delta.

This patch removes the overflow flag from armpmu_event_update and
instead limits the sample_period to half of the max_period for
non-sampling profiling runs.

Signed-off-by: Ming Lei &lt;ming.lei@canonical.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 5727347180ebc6b4a866fcbe00dcb39cc03acb37 upstream.

On ARM, the PMU does not stop counting after an overflow and therefore
IRQ latency affects the new counter value read by the kernel. This is
significant for non-sampling runs where it is possible for the new value
to overtake the previous one, causing the delta to be out by up to
max_period events.

Commit a737823d ("ARM: 6835/1: perf: ensure overflows aren't missed due
to IRQ latency") attempted to fix this problem by allowing interrupt
handlers to pass an overflow flag to the event update function, causing
the overflow calculation to assume that the counter passed through zero
when going from prev to new. Unfortunately, this doesn't work when
overflow occurs on the perf_task_tick path because we have the flag
cleared and end up computing a large negative delta.

This patch removes the overflow flag from armpmu_event_update and
instead limits the sample_period to half of the max_period for
non-sampling profiling runs.

Signed-off-by: Ming Lei &lt;ming.lei@canonical.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: 7345/1: errata: update workaround for A9 erratum #743622</title>
<updated>2012-03-12T19:31:38+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will.deacon@arm.com</email>
</author>
<published>2012-02-24T11:12:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=2ae3680cf82320f15bc142cdfa8b5499d2b17edd'/>
<id>2ae3680cf82320f15bc142cdfa8b5499d2b17edd</id>
<content type='text'>
commit efbc74ace95338484f8d732037b99c7c77098fce upstream.

Erratum #743622 affects all r2 variants of the Cortex-A9 processor, so
ensure that the workaround is applied regardless of the revision.

Reported-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit efbc74ace95338484f8d732037b99c7c77098fce upstream.

Erratum #743622 affects all r2 variants of the Cortex-A9 processor, so
ensure that the workaround is applied regardless of the revision.

Reported-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
</feed>
