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linux/Documentation/unaligned-memory-access.txt

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Documentation about unaligned memory access Here's a document I wrote after figuring out what unaligned memory access is all about. I've tried to cover the information I was looking for when trying to learn about this, without producing a hopelessly detailed/complex spew. I hope it is useful to others. Signed-off-by: Daniel Drake <dsd@gentoo.org> Cc: Rob Landley <rob@landley.net> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Jan Engelhardt <jengelh@computergmbh.de> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Kyle Moffett <mrmacman_g4@mac.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 01:37:30 -08:00
Fix typos in Documentation/unaligned-memory-access.txt This patch deletes a couple of superfluous word occurrences in the document Documentation/unaligned-memory-access.txt. Thanks to Sebastien Dugue for the remark about English usage. Signed-off-by: Dmitri Vorobiev <dmitri.vorobiev@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-02 13:04:45 -07:00
Documentation about unaligned memory access Here's a document I wrote after figuring out what unaligned memory access is all about. I've tried to cover the information I was looking for when trying to learn about this, without producing a hopelessly detailed/complex spew. I hope it is useful to others. Signed-off-by: Daniel Drake <dsd@gentoo.org> Cc: Rob Landley <rob@landley.net> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Jan Engelhardt <jengelh@computergmbh.de> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Kyle Moffett <mrmacman_g4@mac.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 01:37:30 -08:00
ether_addr_equal: Optimize implementation, remove unused compare_ether_addr Add a new check for CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS to reduce the number of or's used in the ether_addr_equal comparison to very slightly improve function performance. Simplify the ether_addr_equal_64bits implementation. Integrate and remove the zap_last_2bytes helper as it's now used only once. Remove the now unused compare_ether_addr function. Update the unaligned-memory-access documentation to remove the compare_ether_addr description and show how unaligned accesses could occur with ether_addr_equal. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-05 14:54:38 -08:00
Documentation about unaligned memory access Here's a document I wrote after figuring out what unaligned memory access is all about. I've tried to cover the information I was looking for when trying to learn about this, without producing a hopelessly detailed/complex spew. I hope it is useful to others. Signed-off-by: Daniel Drake <dsd@gentoo.org> Cc: Rob Landley <rob@landley.net> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Jan Engelhardt <jengelh@computergmbh.de> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Kyle Moffett <mrmacman_g4@mac.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 01:37:30 -08:00
ether_addr_equal: Optimize implementation, remove unused compare_ether_addr Add a new check for CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS to reduce the number of or's used in the ether_addr_equal comparison to very slightly improve function performance. Simplify the ether_addr_equal_64bits implementation. Integrate and remove the zap_last_2bytes helper as it's now used only once. Remove the now unused compare_ether_addr function. Update the unaligned-memory-access documentation to remove the compare_ether_addr description and show how unaligned accesses could occur with ether_addr_equal. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-05 14:54:38 -08:00
Documentation about unaligned memory access Here's a document I wrote after figuring out what unaligned memory access is all about. I've tried to cover the information I was looking for when trying to learn about this, without producing a hopelessly detailed/complex spew. I hope it is useful to others. Signed-off-by: Daniel Drake <dsd@gentoo.org> Cc: Rob Landley <rob@landley.net> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Jan Engelhardt <jengelh@computergmbh.de> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Kyle Moffett <mrmacman_g4@mac.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 01:37:30 -08:00
ether_addr_equal: Optimize implementation, remove unused compare_ether_addr Add a new check for CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS to reduce the number of or's used in the ether_addr_equal comparison to very slightly improve function performance. Simplify the ether_addr_equal_64bits implementation. Integrate and remove the zap_last_2bytes helper as it's now used only once. Remove the now unused compare_ether_addr function. Update the unaligned-memory-access documentation to remove the compare_ether_addr description and show how unaligned accesses could occur with ether_addr_equal. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-05 14:54:38 -08:00
Documentation about unaligned memory access Here's a document I wrote after figuring out what unaligned memory access is all about. I've tried to cover the information I was looking for when trying to learn about this, without producing a hopelessly detailed/complex spew. I hope it is useful to others. Signed-off-by: Daniel Drake <dsd@gentoo.org> Cc: Rob Landley <rob@landley.net> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Jan Engelhardt <jengelh@computergmbh.de> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Kyle Moffett <mrmacman_g4@mac.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 01:37:30 -08:00
ether_addr_equal: Optimize implementation, remove unused compare_ether_addr Add a new check for CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS to reduce the number of or's used in the ether_addr_equal comparison to very slightly improve function performance. Simplify the ether_addr_equal_64bits implementation. Integrate and remove the zap_last_2bytes helper as it's now used only once. Remove the now unused compare_ether_addr function. Update the unaligned-memory-access documentation to remove the compare_ether_addr description and show how unaligned accesses could occur with ether_addr_equal. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-05 14:54:38 -08:00
Documentation about unaligned memory access Here's a document I wrote after figuring out what unaligned memory access is all about. I've tried to cover the information I was looking for when trying to learn about this, without producing a hopelessly detailed/complex spew. I hope it is useful to others. Signed-off-by: Daniel Drake <dsd@gentoo.org> Cc: Rob Landley <rob@landley.net> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Jan Engelhardt <jengelh@computergmbh.de> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Kyle Moffett <mrmacman_g4@mac.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 01:37:30 -08:00
ether_addr_equal: Optimize implementation, remove unused compare_ether_addr Add a new check for CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS to reduce the number of or's used in the ether_addr_equal comparison to very slightly improve function performance. Simplify the ether_addr_equal_64bits implementation. Integrate and remove the zap_last_2bytes helper as it's now used only once. Remove the now unused compare_ether_addr function. Update the unaligned-memory-access documentation to remove the compare_ether_addr description and show how unaligned accesses could occur with ether_addr_equal. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-05 14:54:38 -08:00
Documentation about unaligned memory access Here's a document I wrote after figuring out what unaligned memory access is all about. I've tried to cover the information I was looking for when trying to learn about this, without producing a hopelessly detailed/complex spew. I hope it is useful to others. Signed-off-by: Daniel Drake <dsd@gentoo.org> Cc: Rob Landley <rob@landley.net> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Jan Engelhardt <jengelh@computergmbh.de> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Kyle Moffett <mrmacman_g4@mac.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 01:37:30 -08:00
ether_addr_equal: Optimize implementation, remove unused compare_ether_addr Add a new check for CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS to reduce the number of or's used in the ether_addr_equal comparison to very slightly improve function performance. Simplify the ether_addr_equal_64bits implementation. Integrate and remove the zap_last_2bytes helper as it's now used only once. Remove the now unused compare_ether_addr function. Update the unaligned-memory-access documentation to remove the compare_ether_addr description and show how unaligned accesses could occur with ether_addr_equal. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-05 14:54:38 -08:00
Documentation about unaligned memory access Here's a document I wrote after figuring out what unaligned memory access is all about. I've tried to cover the information I was looking for when trying to learn about this, without producing a hopelessly detailed/complex spew. I hope it is useful to others. Signed-off-by: Daniel Drake <dsd@gentoo.org> Cc: Rob Landley <rob@landley.net> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Jan Engelhardt <jengelh@computergmbh.de> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Kyle Moffett <mrmacman_g4@mac.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 01:37:30 -08:00
Fix typos in Documentation/unaligned-memory-access.txt This patch deletes a couple of superfluous word occurrences in the document Documentation/unaligned-memory-access.txt. Thanks to Sebastien Dugue for the remark about English usage. Signed-off-by: Dmitri Vorobiev <dmitri.vorobiev@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-02 13:04:45 -07:00
Documentation about unaligned memory access Here's a document I wrote after figuring out what unaligned memory access is all about. I've tried to cover the information I was looking for when trying to learn about this, without producing a hopelessly detailed/complex spew. I hope it is useful to others. Signed-off-by: Daniel Drake <dsd@gentoo.org> Cc: Rob Landley <rob@landley.net> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Jan Engelhardt <jengelh@computergmbh.de> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Kyle Moffett <mrmacman_g4@mac.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 01:37:30 -08:00
introduce HAVE_EFFICIENT_UNALIGNED_ACCESS Kconfig symbol In many cases, especially in networking, it can be beneficial to know at compile time whether the architecture can do unaligned accesses efficiently. This patch introduces a new Kconfig symbol HAVE_EFFICIENT_UNALIGNED_ACCESS for that purpose and adds it to the powerpc and x86 architectures. Also add some documentation about alignment and networking, and especially one intended use of this symbol. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Acked-by: Sam Ravnborg <sam@ravnborg.org> Acked-by: Ingo Molnar <mingo@elte.hu> [x86 architecture part] Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 01:45:33 -07:00
Documentation about unaligned memory access Here's a document I wrote after figuring out what unaligned memory access is all about. I've tried to cover the information I was looking for when trying to learn about this, without producing a hopelessly detailed/complex spew. I hope it is useful to others. Signed-off-by: Daniel Drake <dsd@gentoo.org> Cc: Rob Landley <rob@landley.net> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Jan Engelhardt <jengelh@computergmbh.de> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Kyle Moffett <mrmacman_g4@mac.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 01:37:30 -08:00
introduce HAVE_EFFICIENT_UNALIGNED_ACCESS Kconfig symbol In many cases, especially in networking, it can be beneficial to know at compile time whether the architecture can do unaligned accesses efficiently. This patch introduces a new Kconfig symbol HAVE_EFFICIENT_UNALIGNED_ACCESS for that purpose and adds it to the powerpc and x86 architectures. Also add some documentation about alignment and networking, and especially one intended use of this symbol. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Acked-by: Sam Ravnborg <sam@ravnborg.org> Acked-by: Ingo Molnar <mingo@elte.hu> [x86 architecture part] Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 01:45:33 -07:00
Documentation about unaligned memory access Here's a document I wrote after figuring out what unaligned memory access is all about. I've tried to cover the information I was looking for when trying to learn about this, without producing a hopelessly detailed/complex spew. I hope it is useful to others. Signed-off-by: Daniel Drake <dsd@gentoo.org> Cc: Rob Landley <rob@landley.net> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Jan Engelhardt <jengelh@computergmbh.de> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Kyle Moffett <mrmacman_g4@mac.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 01:37:30 -08:00
introduce HAVE_EFFICIENT_UNALIGNED_ACCESS Kconfig symbol In many cases, especially in networking, it can be beneficial to know at compile time whether the architecture can do unaligned accesses efficiently. This patch introduces a new Kconfig symbol HAVE_EFFICIENT_UNALIGNED_ACCESS for that purpose and adds it to the powerpc and x86 architectures. Also add some documentation about alignment and networking, and especially one intended use of this symbol. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Acked-by: Sam Ravnborg <sam@ravnborg.org> Acked-by: Ingo Molnar <mingo@elte.hu> [x86 architecture part] Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 01:45:33 -07:00
Documentation about unaligned memory access Here's a document I wrote after figuring out what unaligned memory access is all about. I've tried to cover the information I was looking for when trying to learn about this, without producing a hopelessly detailed/complex spew. I hope it is useful to others. Signed-off-by: Daniel Drake <dsd@gentoo.org> Cc: Rob Landley <rob@landley.net> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Jan Engelhardt <jengelh@computergmbh.de> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Kyle Moffett <mrmacman_g4@mac.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 01:37:30 -08:00