<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch/arc/kernel/smp.c, branch v7.2</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>arc: validate DT CPU map strings before parsing them</title>
<updated>2026-07-10T22:26:04+00:00</updated>
<author>
<name>Pengpeng Hou</name>
<email>pengpeng@iscas.ac.cn</email>
</author>
<published>2026-07-10T22:26:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=460511c11f0d67e62c6526b191b205eafc8033b2'/>
<id>460511c11f0d67e62c6526b191b205eafc8033b2</id>
<content type='text'>
arc_get_cpu_map() fetches the possible-cpus or present-cpus property
from the flat DT and immediately passes the raw pointer to
cpulist_parse(). That parser expects a NUL-terminated text buffer, but
this path does not prove that the DT property is terminated within its
declared bounds.

Reject unterminated CPU-map properties before handing them to
cpulist_parse().

Changes since v1:
- fold the NUL-termination check into the initial lookup test, as
  suggested by Vineet Gupta

Signed-off-by: Pengpeng Hou &lt;pengpeng@iscas.ac.cn&gt;
Signed-off-by: Vineet Gupta &lt;vgupta@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
arc_get_cpu_map() fetches the possible-cpus or present-cpus property
from the flat DT and immediately passes the raw pointer to
cpulist_parse(). That parser expects a NUL-terminated text buffer, but
this path does not prove that the DT property is terminated within its
declared bounds.

Reject unterminated CPU-map properties before handing them to
cpulist_parse().

Changes since v1:
- fold the NUL-termination check into the initial lookup test, as
  suggested by Vineet Gupta

Signed-off-by: Pengpeng Hou &lt;pengpeng@iscas.ac.cn&gt;
Signed-off-by: Vineet Gupta &lt;vgupta@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>smp: Consolidate smp_prepare_boot_cpu()</title>
<updated>2024-03-04T11:01:54+00:00</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2024-03-04T10:12:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=712610725c48c829e42bebfc9908cd92468e2731'/>
<id>712610725c48c829e42bebfc9908cd92468e2731</id>
<content type='text'>
There is no point in having seven architectures implementing the same empty
stub.

Provide a weak function in the init code and remove the stubs.

This also allows to utilize the function on UP which is required to
sanitize the per CPU handling on X86 UP.

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Link: https://lore.kernel.org/r/20240304005104.567671691@linutronix.de
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
There is no point in having seven architectures implementing the same empty
stub.

Provide a weak function in the init code and remove the stubs.

This also allows to utilize the function on UP which is required to
sanitize the per CPU handling on X86 UP.

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Link: https://lore.kernel.org/r/20240304005104.567671691@linutronix.de
</pre>
</div>
</content>
</entry>
<entry>
<title>ARC: -Wmissing-prototype warning fixes</title>
<updated>2023-08-13T23:53:02+00:00</updated>
<author>
<name>Vineet Gupta</name>
<email>vgupta@kernel.org</email>
</author>
<published>2023-08-13T01:23:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4d3696801bad2a037832c15a8d21dfe0c529d9cd'/>
<id>4d3696801bad2a037832c15a8d21dfe0c529d9cd</id>
<content type='text'>
Anrd reported [1] new compiler warnings due to -Wmissing-protype.
These are for non static functions mostly used in asm code hence not
exported already. Fix this by adding the prototypes.

[1] https://lore.kernel.org/lkml/20230810141947.1236730-1-arnd@kernel.org

Reviewed-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Vineet Gupta &lt;vgupta@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Anrd reported [1] new compiler warnings due to -Wmissing-protype.
These are for non static functions mostly used in asm code hence not
exported already. Fix this by adding the prototypes.

[1] https://lore.kernel.org/lkml/20230810141947.1236730-1-arnd@kernel.org

Reviewed-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Vineet Gupta &lt;vgupta@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>treewide: Trace IPIs sent via smp_send_reschedule()</title>
<updated>2023-03-24T10:01:28+00:00</updated>
<author>
<name>Valentin Schneider</name>
<email>vschneid@redhat.com</email>
</author>
<published>2023-03-07T14:35:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4c8c3c7f70a6779d30f5492acbc9978f4636fe7a'/>
<id>4c8c3c7f70a6779d30f5492acbc9978f4636fe7a</id>
<content type='text'>
To be able to trace invocations of smp_send_reschedule(), rename the
arch-specific definitions of it to arch_smp_send_reschedule() and wrap it
into an smp_send_reschedule() that contains a tracepoint.

Changes to include the declaration of the tracepoint were driven by the
following coccinelle script:

  @func_use@
  @@
  smp_send_reschedule(...);

  @include@
  @@
  #include &lt;trace/events/ipi.h&gt;

  @no_include depends on func_use &amp;&amp; !include@
  @@
    #include &lt;...&gt;
  +
  + #include &lt;trace/events/ipi.h&gt;

[csky bits]
[riscv bits]
Signed-off-by: Valentin Schneider &lt;vschneid@redhat.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Acked-by: Guo Ren &lt;guoren@kernel.org&gt;
Acked-by: Palmer Dabbelt &lt;palmer@rivosinc.com&gt;
Link: https://lore.kernel.org/r/20230307143558.294354-6-vschneid@redhat.com
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
To be able to trace invocations of smp_send_reschedule(), rename the
arch-specific definitions of it to arch_smp_send_reschedule() and wrap it
into an smp_send_reschedule() that contains a tracepoint.

Changes to include the declaration of the tracepoint were driven by the
following coccinelle script:

  @func_use@
  @@
  smp_send_reschedule(...);

  @include@
  @@
  #include &lt;trace/events/ipi.h&gt;

  @no_include depends on func_use &amp;&amp; !include@
  @@
    #include &lt;...&gt;
  +
  + #include &lt;trace/events/ipi.h&gt;

[csky bits]
[riscv bits]
Signed-off-by: Valentin Schneider &lt;vschneid@redhat.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Acked-by: Guo Ren &lt;guoren@kernel.org&gt;
Acked-by: Palmer Dabbelt &lt;palmer@rivosinc.com&gt;
Link: https://lore.kernel.org/r/20230307143558.294354-6-vschneid@redhat.com
</pre>
</div>
</content>
</entry>
<entry>
<title>ARC: Fix comment typo</title>
<updated>2022-10-17T23:32:11+00:00</updated>
<author>
<name>Jilin Yuan</name>
<email>yuanjilin@cdjrlc.com</email>
</author>
<published>2022-05-08T03:02:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=63d1dfd067f07c11eafe05ebadc5896491416f86'/>
<id>63d1dfd067f07c11eafe05ebadc5896491416f86</id>
<content type='text'>
 - Remove one of the repeated 'call' in comment line 396.
 - Delete the redundant word 'to', 'since'

Signed-off-by: Jilin Yuan &lt;yuanjilin@cdjrlc.com&gt;
Signed-off-by: Vineet Gupta &lt;vgupta@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
 - Remove one of the repeated 'call' in comment line 396.
 - Delete the redundant word 'to', 'since'

Signed-off-by: Jilin Yuan &lt;yuanjilin@cdjrlc.com&gt;
Signed-off-by: Vineet Gupta &lt;vgupta@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>profile: setup_profiling_timer() is moslty not implemented</title>
<updated>2022-07-30T01:12:36+00:00</updated>
<author>
<name>Ben Dooks</name>
<email>ben-linux@fluff.org</email>
</author>
<published>2022-07-21T19:55:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=787dbea11a5d6843999ff71a3fb9aa1ed6d5d889'/>
<id>787dbea11a5d6843999ff71a3fb9aa1ed6d5d889</id>
<content type='text'>
The setup_profiling_timer() is mostly un-implemented by many
architectures.  In many places it isn't guarded by CONFIG_PROFILE which is
needed for it to be used.  Make it a weak symbol in kernel/profile.c and
remove the 'return -EINVAL' implementations from the kenrel.

There are a couple of architectures which do return 0 from the
setup_profiling_timer() function but they don't seem to do anything else
with it.  To keep the /proc compatibility for now, leave these for a
future update or removal.

On ARM, this fixes the following sparse warning:
arch/arm/kernel/smp.c:793:5: warning: symbol 'setup_profiling_timer' was not declared. Should it be static?

Link: https://lkml.kernel.org/r/20220721195509.418205-1-ben-linux@fluff.org
Signed-off-by: Ben Dooks &lt;ben-linux@fluff.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The setup_profiling_timer() is mostly un-implemented by many
architectures.  In many places it isn't guarded by CONFIG_PROFILE which is
needed for it to be used.  Make it a weak symbol in kernel/profile.c and
remove the 'return -EINVAL' implementations from the kenrel.

There are a couple of architectures which do return 0 from the
setup_profiling_timer() function but they don't seem to do anything else
with it.  To keep the /proc compatibility for now, leave these for a
future update or removal.

On ARM, this fixes the following sparse warning:
arch/arm/kernel/smp.c:793:5: warning: symbol 'setup_profiling_timer' was not declared. Should it be static?

Link: https://lkml.kernel.org/r/20220721195509.418205-1-ben-linux@fluff.org
Signed-off-by: Ben Dooks &lt;ben-linux@fluff.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ARC: remove redundant READ_ONCE() in cmpxchg loop</title>
<updated>2022-04-18T21:47:05+00:00</updated>
<author>
<name>Bang Li</name>
<email>libang.linuxer@gmail.com</email>
</author>
<published>2022-03-19T02:03:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=c6ed4d84a2c49de7d6f490144cca7b4a4831fb6e'/>
<id>c6ed4d84a2c49de7d6f490144cca7b4a4831fb6e</id>
<content type='text'>
This patch reverts commit 7082a29c22ac ("ARC: use ACCESS_ONCE in cmpxchg
loop").

It is not necessary to use READ_ONCE() because cmpxchg contains barrier. We
can get it from commit d57f727264f1 ("ARC: add compiler barrier to LLSC
based cmpxchg").

Signed-off-by: Bang Li &lt;libang.linuxer@gmail.com&gt;
Signed-off-by: Vineet Gupta &lt;vgupta@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This patch reverts commit 7082a29c22ac ("ARC: use ACCESS_ONCE in cmpxchg
loop").

It is not necessary to use READ_ONCE() because cmpxchg contains barrier. We
can get it from commit d57f727264f1 ("ARC: add compiler barrier to LLSC
based cmpxchg").

Signed-off-by: Bang Li &lt;libang.linuxer@gmail.com&gt;
Signed-off-by: Vineet Gupta &lt;vgupta@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ARC: fix typos in comments</title>
<updated>2022-04-18T19:20:23+00:00</updated>
<author>
<name>Julia Lawall</name>
<email>Julia.Lawall@inria.fr</email>
</author>
<published>2022-03-18T10:37:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=ecaa054fc4c65ad337ec57aef2c6b041e0ef8f91'/>
<id>ecaa054fc4c65ad337ec57aef2c6b041e0ef8f91</id>
<content type='text'>
Various spelling mistakes in comments.
Detected with the help of Coccinelle.

Signed-off-by: Julia Lawall &lt;Julia.Lawall@inria.fr&gt;
Signed-off-by: Vineet Gupta &lt;vgupta@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Various spelling mistakes in comments.
Detected with the help of Coccinelle.

Signed-off-by: Julia Lawall &lt;Julia.Lawall@inria.fr&gt;
Signed-off-by: Vineet Gupta &lt;vgupta@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ARC: switch to generic bitops</title>
<updated>2021-08-24T21:25:47+00:00</updated>
<author>
<name>Vineet Gupta</name>
<email>vgupta@kernel.org</email>
</author>
<published>2018-09-04T23:11:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=cea43147905f1c2b7b48104a5304cf5229f45bec'/>
<id>cea43147905f1c2b7b48104a5304cf5229f45bec</id>
<content type='text'>
 - !LLSC now only needs a single spinlock for atomics and bitops

 - Some codegen changes (slight bloat) with generic bitops

   1. code increase due to LD-check-atomic paradigm vs. unconditonal
      atomic (but dirty'ing the cache line even if set already).
      So despite increase, generic is right thing to do.

   2. code decrease (but use of costlier instructions such as DIV vs.
      shifts based math) due to signed arithmetic.
      This needs to be revisited seperately.

     arc:
     static inline int test_bit(unsigned int nr, const volatile unsigned long *addr)
                                ^^^^^^^^^^^^
     generic:
     static inline int test_bit(int nr, const volatile unsigned long *addr)
                                ^^^

Link: https://lore.kernel.org/r/20180830135749.GA13005@arm.com
Signed-off-by: Will Deacon &lt;will@kernel.org&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
[vgupta: wrote patch based on Will's poc, analysed codegen diffs]
Signed-off-by: Vineet Gupta &lt;vgupta@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
 - !LLSC now only needs a single spinlock for atomics and bitops

 - Some codegen changes (slight bloat) with generic bitops

   1. code increase due to LD-check-atomic paradigm vs. unconditonal
      atomic (but dirty'ing the cache line even if set already).
      So despite increase, generic is right thing to do.

   2. code decrease (but use of costlier instructions such as DIV vs.
      shifts based math) due to signed arithmetic.
      This needs to be revisited seperately.

     arc:
     static inline int test_bit(unsigned int nr, const volatile unsigned long *addr)
                                ^^^^^^^^^^^^
     generic:
     static inline int test_bit(int nr, const volatile unsigned long *addr)
                                ^^^

Link: https://lore.kernel.org/r/20180830135749.GA13005@arm.com
Signed-off-by: Will Deacon &lt;will@kernel.org&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
[vgupta: wrote patch based on Will's poc, analysed codegen diffs]
Signed-off-by: Vineet Gupta &lt;vgupta@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arch/arc/kernel/: fix misspellings using codespell tool</title>
<updated>2021-08-24T21:25:46+00:00</updated>
<author>
<name>Changcheng Deng</name>
<email>deng.changcheng@zte.com.cn</email>
</author>
<published>2021-08-13T16:30:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=82a423053eb3cf27209c78ce1852ea18d173722a'/>
<id>82a423053eb3cf27209c78ce1852ea18d173722a</id>
<content type='text'>
Some typos are found out by codespell tool:

./intc-compact.c:145: prioity ==&gt; priority
./smp.c:286: recevier ==&gt; receiver
./stacktrace.c:152 prelogue ==&gt; prologue

Fix typos found by codespell.

Reported-by: Zeal Robot &lt;zealci@zte.com.cn&gt;
Signed-off-by: Changcheng Deng &lt;deng.changcheng@zte.com.cn&gt;
Signed-off-by: Yi Wang &lt;wang.yi59@zte.com.cn&gt;
Signed-off-by: Vineet Gupta &lt;vgupta@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Some typos are found out by codespell tool:

./intc-compact.c:145: prioity ==&gt; priority
./smp.c:286: recevier ==&gt; receiver
./stacktrace.c:152 prelogue ==&gt; prologue

Fix typos found by codespell.

Reported-by: Zeal Robot &lt;zealci@zte.com.cn&gt;
Signed-off-by: Changcheng Deng &lt;deng.changcheng@zte.com.cn&gt;
Signed-off-by: Yi Wang &lt;wang.yi59@zte.com.cn&gt;
Signed-off-by: Vineet Gupta &lt;vgupta@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
