<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/kernel/power/qos.c, branch v7.1</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Convert 'alloc_obj' family to use the new default GFP_KERNEL argument</title>
<updated>2026-02-22T01:09:51+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2026-02-22T00:37:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=bf4afc53b77aeaa48b5409da5c8da6bb4eff7f43'/>
<id>bf4afc53b77aeaa48b5409da5c8da6bb4eff7f43</id>
<content type='text'>
This was done entirely with mindless brute force, using

    git grep -l '\&lt;k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This was done entirely with mindless brute force, using

    git grep -l '\&lt;k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>treewide: Replace kmalloc with kmalloc_obj for non-scalar types</title>
<updated>2026-02-21T09:02:28+00:00</updated>
<author>
<name>Kees Cook</name>
<email>kees@kernel.org</email>
</author>
<published>2026-02-21T07:49:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=69050f8d6d075dc01af7a5f2f550a8067510366f'/>
<id>69050f8d6d075dc01af7a5f2f550a8067510366f</id>
<content type='text'>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook &lt;kees@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook &lt;kees@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: QoS: Introduce a CPU system wakeup QoS limit</title>
<updated>2025-11-25T18:01:29+00:00</updated>
<author>
<name>Ulf Hansson</name>
<email>ulf.hansson@linaro.org</email>
</author>
<published>2025-11-25T11:26:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=a4e6512a79d8486dccf3e8b066e5d6bd5ff95446'/>
<id>a4e6512a79d8486dccf3e8b066e5d6bd5ff95446</id>
<content type='text'>
Some platforms supports multiple low power states for CPUs that can be used
when entering system-wide suspend. Currently we are always selecting the
deepest possible state for the CPUs, which can break the system wakeup
latency constraint that may be required for a use case.

Let's take the first step towards addressing this problem, by introducing
an interface for user space, that allows us to specify the CPU system
wakeup QoS limit. Subsequent changes will start taking into account the new
QoS limit.

Reviewed-by: Dhruva Gole &lt;d-gole@ti.com&gt;
Reviewed-by: Kevin Hilman (TI) &lt;khilman@baylibre.com&gt;
Tested-by: Kevin Hilman (TI) &lt;khilman@baylibre.com&gt;
Signed-off-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Link: https://patch.msgid.link/20251125112650.329269-2-ulf.hansson@linaro.org
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Some platforms supports multiple low power states for CPUs that can be used
when entering system-wide suspend. Currently we are always selecting the
deepest possible state for the CPUs, which can break the system wakeup
latency constraint that may be required for a use case.

Let's take the first step towards addressing this problem, by introducing
an interface for user space, that allows us to specify the CPU system
wakeup QoS limit. Subsequent changes will start taking into account the new
QoS limit.

Reviewed-by: Dhruva Gole &lt;d-gole@ti.com&gt;
Reviewed-by: Kevin Hilman (TI) &lt;khilman@baylibre.com&gt;
Tested-by: Kevin Hilman (TI) &lt;khilman@baylibre.com&gt;
Signed-off-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Link: https://patch.msgid.link/20251125112650.329269-2-ulf.hansson@linaro.org
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: QoS: Add check to make sure CPU latency is non-negative</title>
<updated>2023-08-22T19:37:29+00:00</updated>
<author>
<name>Clive Lin</name>
<email>clive.lin@mediatek.com</email>
</author>
<published>2023-07-31T06:03:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=5f55836ab41671e005038255fdd60482718d2ca2'/>
<id>5f55836ab41671e005038255fdd60482718d2ca2</id>
<content type='text'>
CPU latency should never be negative, which will be incorrectly high
when converted to unsigned data type.

Commit 8d36694245f2 ("PM: QoS: Add check to make sure CPU freq is
non-negative") makes sure CPU frequency is non-negative to fix incorrect
behavior in freqency QoS.

Add an analogous check to make sure CPU latency is non-negative so as to
prevent this problem from happening in CPU latency QoS.

Signed-off-by: Clive Lin &lt;clive.lin@mediatek.com&gt;
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
CPU latency should never be negative, which will be incorrectly high
when converted to unsigned data type.

Commit 8d36694245f2 ("PM: QoS: Add check to make sure CPU freq is
non-negative") makes sure CPU frequency is non-negative to fix incorrect
behavior in freqency QoS.

Add an analogous check to make sure CPU latency is non-negative so as to
prevent this problem from happening in CPU latency QoS.

Signed-off-by: Clive Lin &lt;clive.lin@mediatek.com&gt;
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: QoS: Restore support for default value on frequency QoS</title>
<updated>2023-07-11T18:09:57+00:00</updated>
<author>
<name>Chungkai Yang</name>
<email>Chung-kai.Yang@mediatek.com</email>
</author>
<published>2023-07-05T08:59:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=3a8395b565b5b4f019b3dc182be4c4541eb35ac8'/>
<id>3a8395b565b5b4f019b3dc182be4c4541eb35ac8</id>
<content type='text'>
Commit 8d36694245f2 ("PM: QoS: Add check to make sure CPU freq is
non-negative") makes sure CPU freq is non-negative to avoid negative
value converting to unsigned data type. However, when the value is
PM_QOS_DEFAULT_VALUE, pm_qos_update_target specifically uses
c-&gt;default_value which is set to FREQ_QOS_MIN/MAX_DEFAULT_VALUE when
cpufreq_policy_alloc is executed, for this case handling.

Adding check for PM_QOS_DEFAULT_VALUE to let default setting work will
fix this problem.

Fixes: 8d36694245f2 ("PM: QoS: Add check to make sure CPU freq is non-negative")
Link: https://lore.kernel.org/lkml/20230626035144.19717-1-Chung-kai.Yang@mediatek.com/
Link: https://lore.kernel.org/lkml/20230627071727.16646-1-Chung-kai.Yang@mediatek.com/
Link: https://lore.kernel.org/lkml/CAJZ5v0gxNOWhC58PHeUhW_tgf6d1fGJVZ1x91zkDdht11yUv-A@mail.gmail.com/
Signed-off-by: Chungkai Yang &lt;Chung-kai.Yang@mediatek.com&gt;
Cc: 6.0+ &lt;stable@vger.kernel.org&gt; # 6.0+
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Commit 8d36694245f2 ("PM: QoS: Add check to make sure CPU freq is
non-negative") makes sure CPU freq is non-negative to avoid negative
value converting to unsigned data type. However, when the value is
PM_QOS_DEFAULT_VALUE, pm_qos_update_target specifically uses
c-&gt;default_value which is set to FREQ_QOS_MIN/MAX_DEFAULT_VALUE when
cpufreq_policy_alloc is executed, for this case handling.

Adding check for PM_QOS_DEFAULT_VALUE to let default setting work will
fix this problem.

Fixes: 8d36694245f2 ("PM: QoS: Add check to make sure CPU freq is non-negative")
Link: https://lore.kernel.org/lkml/20230626035144.19717-1-Chung-kai.Yang@mediatek.com/
Link: https://lore.kernel.org/lkml/20230627071727.16646-1-Chung-kai.Yang@mediatek.com/
Link: https://lore.kernel.org/lkml/CAJZ5v0gxNOWhC58PHeUhW_tgf6d1fGJVZ1x91zkDdht11yUv-A@mail.gmail.com/
Signed-off-by: Chungkai Yang &lt;Chung-kai.Yang@mediatek.com&gt;
Cc: 6.0+ &lt;stable@vger.kernel.org&gt; # 6.0+
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: QoS: Add check to make sure CPU freq is non-negative</title>
<updated>2022-07-26T18:48:33+00:00</updated>
<author>
<name>Shivnandan Kumar</name>
<email>quic_kshivnan@quicinc.com</email>
</author>
<published>2022-07-15T12:25:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=8d36694245f2aec17f03a5e0b2797953d2e36704'/>
<id>8d36694245f2aec17f03a5e0b2797953d2e36704</id>
<content type='text'>
CPU frequency should never be negative.

If some client driver calls freq_qos_update_request with a
negative value which will be very high in absolute terms,
then frequency QoS sets max CPU freq at fmax as it considers
it's absolute value but it will add plist node with negative
priority.

plist node has priority from INT_MIN (highest) to INT_MAX(lowest).
Once priority is set as negative, another client will not be able
to reduce CPU frequency.

Adding check to make sure CPU freq is non-negative will fix
this problem.

Signed-off-by: Shivnandan Kumar &lt;quic_kshivnan@quicinc.com&gt;
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
CPU frequency should never be negative.

If some client driver calls freq_qos_update_request with a
negative value which will be very high in absolute terms,
then frequency QoS sets max CPU freq at fmax as it considers
it's absolute value but it will add plist node with negative
priority.

plist node has priority from INT_MIN (highest) to INT_MAX(lowest).
Once priority is set as negative, another client will not be able
to reduce CPU frequency.

Adding check to make sure CPU freq is non-negative will fix
this problem.

Signed-off-by: Shivnandan Kumar &lt;quic_kshivnan@quicinc.com&gt;
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>treewide: Use fallthrough pseudo-keyword</title>
<updated>2020-08-23T22:36:59+00:00</updated>
<author>
<name>Gustavo A. R. Silva</name>
<email>gustavoars@kernel.org</email>
</author>
<published>2020-08-23T22:36:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=df561f6688fef775baa341a0f5d960becd248b11'/>
<id>df561f6688fef775baa341a0f5d960becd248b11</id>
<content type='text'>
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva &lt;gustavoars@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva &lt;gustavoars@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: QoS: annotate data races in pm_qos_*_value()</title>
<updated>2020-03-03T22:34:51+00:00</updated>
<author>
<name>Qian Cai</name>
<email>cai@lca.pw</email>
</author>
<published>2020-02-26T01:58:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=a534e924c58d2e7c07509521e87d059dd029dca1'/>
<id>a534e924c58d2e7c07509521e87d059dd029dca1</id>
<content type='text'>
The target_value field in struct pm_qos_constraints is used for
lockless access to the effective constraint value of a given QoS
list, so the readers of it cannot expect it to always reflect the
most recent effective constraint value.  However, they can and do
expect it to be equal to a valid effective constraint value computed
at a certain time in the past (event though it may not be the most
recent one), so add READ|WRITE_ONCE() annotations around the
target_value accesses to prevent the compiler from possibly causing
that expectation to be unmet by generating code in an exceptionally
convoluted way.

Signed-off-by: Qian Cai &lt;cai@lca.pw&gt;
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The target_value field in struct pm_qos_constraints is used for
lockless access to the effective constraint value of a given QoS
list, so the readers of it cannot expect it to always reflect the
most recent effective constraint value.  However, they can and do
expect it to be equal to a valid effective constraint value computed
at a certain time in the past (event though it may not be the most
recent one), so add READ|WRITE_ONCE() annotations around the
target_value accesses to prevent the compiler from possibly causing
that expectation to be unmet by generating code in an exceptionally
convoluted way.

Signed-off-by: Qian Cai &lt;cai@lca.pw&gt;
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: QoS: Make CPU latency QoS depend on CONFIG_CPU_IDLE</title>
<updated>2020-02-14T09:37:27+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2020-02-11T23:37:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=814d51f8889bc4afa75f647eeffd5ff0a5620e8d'/>
<id>814d51f8889bc4afa75f647eeffd5ff0a5620e8d</id>
<content type='text'>
Because cpuidle is the only user of the effective constraint coming
from the CPU latency QoS, add #ifdef CONFIG_CPU_IDLE around that code
to avoid building it unnecessarily.

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Reviewed-by: Amit Kucheria &lt;amit.kucheria@linaro.org&gt;
Tested-by: Amit Kucheria &lt;amit.kucheria@linaro.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Because cpuidle is the only user of the effective constraint coming
from the CPU latency QoS, add #ifdef CONFIG_CPU_IDLE around that code
to avoid building it unnecessarily.

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Reviewed-by: Amit Kucheria &lt;amit.kucheria@linaro.org&gt;
Tested-by: Amit Kucheria &lt;amit.kucheria@linaro.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: QoS: Update file information comments</title>
<updated>2020-02-14T09:37:26+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2020-02-11T23:35:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=fe52de36dc5d60960230cabec88c357113d9c32a'/>
<id>fe52de36dc5d60960230cabec88c357113d9c32a</id>
<content type='text'>
Update the file information comments in include/linux/pm_qos.h
and kernel/power/qos.c by adding titles along with copyright and
authors information to them and changing the qos.c description to
better reflect its contents (outdated information is dropped from
it in particular).

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Reviewed-by: Amit Kucheria &lt;amit.kucheria@linaro.org&gt;
Tested-by: Amit Kucheria &lt;amit.kucheria@linaro.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Update the file information comments in include/linux/pm_qos.h
and kernel/power/qos.c by adding titles along with copyright and
authors information to them and changing the qos.c description to
better reflect its contents (outdated information is dropped from
it in particular).

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Reviewed-by: Amit Kucheria &lt;amit.kucheria@linaro.org&gt;
Tested-by: Amit Kucheria &lt;amit.kucheria@linaro.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
