<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch/x86/lib/string_32.c, 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>x86/lib: Audit and remove any unnecessary uses of module.h</title>
<updated>2016-07-14T13:06:58+00:00</updated>
<author>
<name>Paul Gortmaker</name>
<email>paul.gortmaker@windriver.com</email>
</author>
<published>2016-07-14T00:18:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e683014c2113d374b8716a7c938803c2f578efd5'/>
<id>e683014c2113d374b8716a7c938803c2f578efd5</id>
<content type='text'>
Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends.  That changed
when we forked out support for the latter into the export.h file.

This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig.  The advantage
in doing so is that module.h itself sources about 15 other headers;
adding significantly to what we feed cpp, and it can obscure what
headers we are effectively using.

Since module.h was the source for init.h (for __init) and for
export.h (for EXPORT_SYMBOL) we consider each obj-y/bool instance
for the presence of either and replace as needed.  Build testing
revealed a couple implicit header usage issues that were fixed.

Signed-off-by: Paul Gortmaker &lt;paul.gortmaker@windriver.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Link: http://lkml.kernel.org/r/20160714001901.31603-5-paul.gortmaker@windriver.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends.  That changed
when we forked out support for the latter into the export.h file.

This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig.  The advantage
in doing so is that module.h itself sources about 15 other headers;
adding significantly to what we feed cpp, and it can obscure what
headers we are effectively using.

Since module.h was the source for init.h (for __init) and for
export.h (for EXPORT_SYMBOL) we consider each obj-y/bool instance
for the presence of either and replace as needed.  Build testing
revealed a couple implicit header usage issues that were fixed.

Signed-off-by: Paul Gortmaker &lt;paul.gortmaker@windriver.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Link: http://lkml.kernel.org/r/20160714001901.31603-5-paul.gortmaker@windriver.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/i386: Use less assembly in strlen(), speed things up a bit</title>
<updated>2011-12-12T17:33:42+00:00</updated>
<author>
<name>Alexey Dobriyan</name>
<email>adobriyan@gmail.com</email>
</author>
<published>2011-12-11T18:13:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=890890cb8e415e1e7a61bfe3c8e246f710196824'/>
<id>890890cb8e415e1e7a61bfe3c8e246f710196824</id>
<content type='text'>
Current i386 strlen() hardcodes NOT/DEC sequence. DEC is
mentioned to be suboptimal on Core2. So, put only REPNE SCASB
sequence in assembly, compiler can do the rest.

The difference in generated code is like below (MCORE2=y):

	&lt;strlen&gt;:
		push   %edi
		mov    $0xffffffff,%ecx
		mov    %eax,%edi
		xor    %eax,%eax
		repnz scas %es:(%edi),%al
		not    %ecx

	-	dec    %ecx
	-	mov    %ecx,%eax
	+	lea    -0x1(%ecx),%eax

		pop    %edi
		ret

Signed-off-by: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Jan Beulich &lt;JBeulich@suse.com&gt;
Link: http://lkml.kernel.org/r/20111211181319.GA17097@p183.telecom.by
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Current i386 strlen() hardcodes NOT/DEC sequence. DEC is
mentioned to be suboptimal on Core2. So, put only REPNE SCASB
sequence in assembly, compiler can do the rest.

The difference in generated code is like below (MCORE2=y):

	&lt;strlen&gt;:
		push   %edi
		mov    $0xffffffff,%ecx
		mov    %eax,%edi
		xor    %eax,%eax
		repnz scas %es:(%edi),%al
		not    %ecx

	-	dec    %ecx
	-	mov    %ecx,%eax
	+	lea    -0x1(%ecx),%eax

		pop    %edi
		ret

Signed-off-by: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Jan Beulich &lt;JBeulich@suse.com&gt;
Link: http://lkml.kernel.org/r/20111211181319.GA17097@p183.telecom.by
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86: coding style fixes to arch/x86/lib/string_32.c</title>
<updated>2008-08-15T14:53:25+00:00</updated>
<author>
<name>Paolo Ciarrocchi</name>
<email>paolo.ciarrocchi@gmail.com</email>
</author>
<published>2008-08-02T19:25:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=3492cdf0176bde5e35223a1388d59676bc67c145'/>
<id>3492cdf0176bde5e35223a1388d59676bc67c145</id>
<content type='text'>
Before:
total: 21 errors, 0 warnings, 237 lines checked

After:
total: 0 errors, 0 warnings, 237 lines checked

paolo@paolo-desktop:~/linux.trees.git$ md5sum /tmp/string_32.o.*
c55d059ef1612b32a8bb2771a72ae0d5  /tmp/string_32.o.after
c55d059ef1612b32a8bb2771a72ae0d5  /tmp/string_32.o.before

Signed-off-by: Paolo Ciarrocchi &lt;paolo.ciarrocchi@gmail.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>
Before:
total: 21 errors, 0 warnings, 237 lines checked

After:
total: 0 errors, 0 warnings, 237 lines checked

paolo@paolo-desktop:~/linux.trees.git$ md5sum /tmp/string_32.o.*
c55d059ef1612b32a8bb2771a72ae0d5  /tmp/string_32.o.after
c55d059ef1612b32a8bb2771a72ae0d5  /tmp/string_32.o.before

Signed-off-by: Paolo Ciarrocchi &lt;paolo.ciarrocchi@gmail.com&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86: coding style fixes to arch/x86/lib/string_32.c</title>
<updated>2008-04-17T15:40:48+00:00</updated>
<author>
<name>Paolo Ciarrocchi</name>
<email>paolo.ciarrocchi@gmail.com</email>
</author>
<published>2008-02-19T22:09:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=8cf36d2bc5832da17a58c5f10adf2d92d138c992'/>
<id>8cf36d2bc5832da17a58c5f10adf2d92d138c992</id>
<content type='text'>
The patch kills 45 errors and a few warnings.

The file is now error/warning free:
total: 0 errors, 0 warnings, 237 lines checked
arch/x86/lib/string_32.c has no obvious style problems and is ready for submission.

no code changed:

arch/x86/lib/string_32.o:
   text    data     bss     dec     hex filename
    639       0       0     639     27f string_32.o.before
    639       0       0     639     27f string_32.o.after
md5:
2db1c48187cf5113bb595153ee1fc73d  string_32.o.before.asm
2db1c48187cf5113bb595153ee1fc73d  string_32.o.after.asm

Signed-off-by: Paolo Ciarrocchi &lt;paolo.ciarrocchi@gmail.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>
The patch kills 45 errors and a few warnings.

The file is now error/warning free:
total: 0 errors, 0 warnings, 237 lines checked
arch/x86/lib/string_32.c has no obvious style problems and is ready for submission.

no code changed:

arch/x86/lib/string_32.o:
   text    data     bss     dec     hex filename
    639       0       0     639     27f string_32.o.before
    639       0       0     639     27f string_32.o.after
md5:
2db1c48187cf5113bb595153ee1fc73d  string_32.o.before.asm
2db1c48187cf5113bb595153ee1fc73d  string_32.o.after.asm

Signed-off-by: Paolo Ciarrocchi &lt;paolo.ciarrocchi@gmail.com&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>i386: Remove strrchr assembler implementation</title>
<updated>2007-10-17T18:16:23+00:00</updated>
<author>
<name>Andi Kleen</name>
<email>ak@suse.de</email>
</author>
<published>2007-10-17T16:04:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=61d08a9ea3d5fd680213aa7a15fcda69ce11987d'/>
<id>61d08a9ea3d5fd680213aa7a15fcda69ce11987d</id>
<content type='text'>
The constraints in the inline assembler implementation of i386
strrchr() were incorrect and break the build with recent gcc 4.3.
Since there are only very few callers of strrchr() and none of them
are performance relevant just remove the assembler implementation
and use the C fallback instead.

[ tglx: arch/x86 adaptation ]

Cc: rguenther@suse.de
Signed-off-by: Andi Kleen &lt;ak@suse.de&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The constraints in the inline assembler implementation of i386
strrchr() were incorrect and break the build with recent gcc 4.3.
Since there are only very few callers of strrchr() and none of them
are performance relevant just remove the assembler implementation
and use the C fallback instead.

[ tglx: arch/x86 adaptation ]

Cc: rguenther@suse.de
Signed-off-by: Andi Kleen &lt;ak@suse.de&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>i386: move lib</title>
<updated>2007-10-11T09:16:33+00:00</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2007-10-11T09:16:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=44f0257fc316ff4b33aa3438dd8d891b7d6d72b9'/>
<id>44f0257fc316ff4b33aa3438dd8d891b7d6d72b9</id>
<content type='text'>
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</pre>
</div>
</content>
</entry>
</feed>
