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path: root/include/linux/hash.h
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2013-12-17lib: introduce arch optimized hash libraryFrancesco Fusco
We introduce a new hashing library that is meant to be used in the contexts where speed is more important than uniformity of the hashed values. The hash library leverages architecture specific implementation to achieve high performance and fall backs to jhash() for the generic case. On Intel-based x86 architectures, the library can exploit the crc32l instruction, part of the Intel SSE4.2 instruction set, if the instruction is supported by the processor. This implementation is twice as fast as the jhash() implementation on an i7 processor. Additional architectures, such as Arm64 provide instructions for accelerating the computation of CRC, so they could be added as well in follow-up work. Signed-off-by: Francesco Fusco <ffusco@redhat.com> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Thomas Graf <tgraf@redhat.com> Cc: linux-kernel@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-18kprobes: Make hash_64() as always inlinedMasami Hiramatsu
Because hash_64() is called from the get_kprobe() inside int3 handler, kernel causes int3 recursion and crashes if kprobes user puts a probe on it. Usually hash_64() is inlined into caller function, but in some cases, it has instances by gcc's interprocedural constant propagation. This patch uses __always_inline instead of inline to prevent gcc from doing such things. Reported-by: Timo Juhani Lindfors <timo.lindfors@iki.fi> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Nadia Yvette Chambers <nyc@holomorphy.com> Cc: yrl.pp-manager.tt@hitachi.com Cc: David S. Miller <davem@davemloft.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20130314115230.19690.39387.stgit@mhiramat-M0-7522 Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-12-06propagate name change to comments in kernel sourceNadia Yvette Chambers
I've legally changed my name with New York State, the US Social Security Administration, et al. This patch propagates the name change and change in initials and login to comments in the kernel source as well. Signed-off-by: Nadia Yvette Chambers <nyc@holomorphy.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-08-09net: Dont use ifindices in hash fnsPavel Emelyanov
Eric noticed, that when there will be devices with equal indices, some hash functions that use them will become less effective as they could. Fix this in advance by mixing the net_device address into the hash value instead of the device index. This is true for arp and ndisc hash fns. The netlabel, can and llc ones are also ifindex-based, but that three are init_net-only, thus will not be affected. Many thanks to David and Eric for the hash32_ptr implementation! Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-17mm: make HASHED_PAGE_VIRTUAL page_address' struct page argument const.Ian Campbell
Followup to 33dd4e0ec911 "mm: make some struct page's const" which missed the HASHED_PAGE_VIRTUAL case. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Michel Lespinasse <walken@google.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06hash: add explicit u32 and u64 versions of hashMatthew Wilcox
The 32-bit version is more efficient (and apparently gives better hash results than the 64-bit version), so users who are only hashing a 32-bit quantity can now opt to use the 32-bit version explicitly, rather than promoting to a long. Signed-off-by: Matthew Wilcox <willy@linux.intel.com> Cc: William Lee Irwin III <wli@holomorphy.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!