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* treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner2019-05-301-5/+1
| | | | | | | | | | | | | | | | | | | | | Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc/lib: optimise PPC32 memcmpChristophe Leroy2018-06-041-17/+0
| | | | | | | | | | | | | | | | | | | | | | At the time being, memcmp() compares two chunks of memory byte per byte. This patch optimises the comparison by comparing word by word. On the same way as commit 15c2d45d17418 ("powerpc: Add 64bit optimised memcmp"), this patch moves memcmp() into a dedicated file named memcmp_32.S A small benchmark performed on an 8xx comparing two chuncks of 512 bytes performed 100000 times gives: Before : 5852274 TB ticks After: 1488638 TB ticks This is almost 4 times faster Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/lib: optimise 32 bits __clear_user()Christophe Leroy2018-06-041-46/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rewrite clear_user() on the same principle as memset(0), making use of dcbz to clear complete cache lines. This code is a copy/paste of memset(), with some modifications in order to retrieve remaining number of bytes to be cleared, as it needs to be returned in case of error. On the same way as done on PPC64 in commit 17968fbbd19f1 ("powerpc: 64bit optimised __clear_user"), the patch moves __clear_user() into a dedicated file string_32.S On a MPC885, throughput is almost doubled: Before: ~# dd if=/dev/zero of=/dev/null bs=1M count=1000 1048576000 bytes (1000.0MB) copied, 18.990779 seconds, 52.7MB/s After: ~# dd if=/dev/zero of=/dev/null bs=1M count=1000 1048576000 bytes (1000.0MB) copied, 9.611468 seconds, 104.0MB/s On a MPC8321, throughput is multiplied by 2.12: Before: root@vgoippro:~# dd if=/dev/zero of=/dev/null bs=1M count=1000 1048576000 bytes (1000.0MB) copied, 6.844352 seconds, 146.1MB/s After: root@vgoippro:~# dd if=/dev/zero of=/dev/null bs=1M count=1000 1048576000 bytes (1000.0MB) copied, 3.218854 seconds, 310.7MB/s Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/lib: Adjust .balign inside string functions for PPC32Christophe Leroy2018-06-041-3/+4
| | | | | | | | | | | | | | | | | | | | commit 87a156fb18fe1 ("Align hot loops of some string functions") degraded the performance of string functions by adding useless nops A simple benchmark on an 8xx calling 100000x a memchr() that matches the first byte runs in 41668 TB ticks before this patch and in 35986 TB ticks after this patch. So this gives an improvement of approx 10% Another benchmark doing the same with a memchr() matching the 128th byte runs in 1011365 TB ticks before this patch and 1005682 TB ticks after this patch, so regardless on the number of loops, removing those useless nops improves the test by 5683 TB ticks. Fixes: 87a156fb18fe1 ("Align hot loops of some string functions") Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc: EX_TABLE macro for exception tablesNicholas Piggin2016-11-141-7/+4
| | | | | | | | | | | | This macro is taken from s390, and allows more flexibility in changing exception table format. mpe: Put it in ppc_asm.h and only define one version using stringinfy_in_c(). Add some empty definitions and headers to keep the selftests happy. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* ppc: move exports to definitionsAl Viro2016-08-071-0/+6
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* powerpc: Align hot loops of some string functionsAnton Blanchard2016-06-141-0/+3
| | | | | | | | Align the hot loops in our assembly implementation of strncpy(), strncmp() and memchr(). Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc: Remove assembly versions of strcpy, strcat, strlen and strcmpAnton Blanchard2016-06-141-41/+0
| | | | | | | | | | | | | A number of our assembly implementations of string functions do not align their hot loops. I was going to align them manually, but I realised that they are are almost instruction for instruction identical to what gcc produces, with the advantage that gcc does align them. In light of that, let's just remove the assembly versions. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc: Add 64bit optimised memcmpAnton Blanchard2015-01-231-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I noticed ksm spending quite a lot of time in memcmp on a large KVM box. The current memcmp loop is very unoptimised - byte at a time compares with no loop unrolling. We can do much much better. Optimise the loop in a few ways: - Unroll the byte at a time loop - For large (at least 32 byte) comparisons that are also 8 byte aligned, use an unrolled modulo scheduled loop using 8 byte loads. This is similar to our glibc memcmp. A simple microbenchmark testing 10000000 iterations of an 8192 byte memcmp was used to measure the performance: baseline: 29.93 s modified: 1.70 s Just over 17x faster. v2: Incorporated some suggestions from Segher: - Use andi. instead of rdlicl. - Convert bdnzt eq, to bdnz. It's just duplicating the earlier compare and was a relic from a previous version. - Don't use cr5, we have plans to use that CR field for fast local atomics. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc: 64bit optimised __clear_userAnton Blanchard2012-07-031-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I noticed __clear_user high up in a profile of one of my RAID stress tests. The testcase was doing a dd from /dev/zero which ends up calling __clear_user. __clear_user is basically a loop with a single 4 byte store which is horribly slow. We can do much better by aligning the desination and doing 32 bytes of 8 byte stores in a loop. The following testcase was used to verify the patch: http://ozlabs.org/~anton/junkcode/stress_clear_user.c To show the improvement in performance I ran a dd from /dev/zero to /dev/null on a POWER7 box: Before: # dd if=/dev/zero of=/dev/null bs=1M count=10000 10485760000 bytes (10 GB) copied, 3.72379 s, 2.8 GB/s After: # time dd if=/dev/zero of=/dev/null bs=1M count=10000 10485760000 bytes (10 GB) copied, 0.728318 s, 14.4 GB/s Over 5x faster. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc: Use the new generic strncpy_from_user() and strnlen_user()Paul Mackerras2012-05-271-45/+0
| | | | | | | | | | This is much the same as for SPARC except that we can do the find_zero() function more efficiently using the count-leading-zeroes instructions. Tested on 32-bit and 64-bit PowerPC. Signed-off-by: Paul Mackerras <paulus@samba.org> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* powerpc: Fix string library functionsAndreas Schwab2010-05-211-8/+8
| | | | | | | | | | | | | The powerpc strncmp implementation does not correctly handle a zero length, despite the claim in 0119536cd314ef95553604208c25bc35581f7f0a (Add hand-coded assembly strcmp). Additionally, all the length arguments are size_t, not int, so use PPC_LCMPI and eq instead of cmpwi and le throughout. Signed-off-by: Andreas Schwab <schwab@linux-m68k.org> Acked-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc: Fix handling of strncmp with zero lenJeff Mahoney2010-04-071-1/+3
| | | | | | | | | | | | | | | | | | Commit 0119536c, which added the assembly version of strncmp to powerpc, mentions that it adds two instructions to the version from boot/string.S to allow it to handle len=0. Unfortunately, it doesn't always return 0 when that is the case. The length is passed in r5, but the return value is passed back in r3. In certain cases, this will happen to work. Otherwise it will pass back the address of the first string as the return value. This patch lifts the len <= 0 handling code from memcpy to handle that case. Reported by: Christian_Sellars@symantec.com Signed-off-by: Jeff Mahoney <jeffm@suse.com> CC: <stable@kernel.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc: Use PPC_LONG and PPC_LONG_ALIGN in lib/string.SMichael Ellerman2008-07-221-12/+6
| | | | | | | | | | Replace ifdef clutter with the PPC_LONG and PPC_LONG_ALIGN macros for readability. No change to the generated code. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* [POWERPC] Add hand-coded assembly strcmpSteven Rostedt2008-04-071-0/+14
| | | | | | | | | | We have an assembly version of strncmp for the bootwrapper, but not for the kernel, so we end up using the C version in the kernel. This takes the strncmp code from the bootup and copies it to the kernel proper, adding two instructions so it copes correctly with len==0. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
* Remove obsolete #include <linux/config.h>Jörn Engel2006-06-301-1/+0
| | | | | Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* powerpc: Use reg.h instead of processor.h when we just want reg namesPaul Mackerras2005-10-101-5/+0
| | | | | | | Now that the register names and bit definitions are all in reg.h, use that instead of processor.h in assembly code in a few places. Signed-off-by: Paul Mackerras <paulus@samba.org>
* powerpc: Merge enough to start building in arch/powerpc.Paul Mackerras2005-09-261-0/+203
This creates the directory structure under arch/powerpc and a bunch of Kconfig files. It does a first-cut merge of arch/powerpc/mm, arch/powerpc/lib and arch/powerpc/platforms/powermac. This is enough to build a 32-bit powermac kernel with ARCH=powerpc. For now we are getting some unmerged files from arch/ppc/kernel and arch/ppc/syslib, or arch/ppc64/kernel. This makes some minor changes to files in those directories and files outside arch/powerpc. The boot directory is still not merged. That's going to be interesting. Signed-off-by: Paul Mackerras <paulus@samba.org>
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