kernel/arch/powerpc/lib/Makefile, branch linux-4.3.y

powerpc: Only use -mabi=altivec if toolchain supports it

2015-06-11T07:33:05Z

The -mabi=altivec option is not recognised on LLVM, so use call cc-option to check for support. Signed-off-by: Anton Blanchard Signed-off-by: Michael Ellerman

powerpc/lib: Makefile, use obj64-y to consolidate 64-bit rules

2015-01-28T04:00:24Z

Signed-off-by: Michael Ellerman

powerpc/lib: Makefile, consolidate obj-y sections

2015-01-28T04:00:24Z

Signed-off-by: Michael Ellerman

powerpc: Add 64bit optimised memcmp

2015-01-23T03:02:55Z

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 Signed-off-by: Michael Ellerman

powerpc/lib: Do not include string.o in obj-y twice

2014-12-29T04:45:55Z

In the Makefile, string.o (which is generated from string.S) is included into the list of objects being built unconditionally (obj-y) in line 12. Additionally, if CONFIG_PPC64 is set, it is included again in line 17. This patch removes the latter unnecessary inclusion. Signed-off-by: Andreas Ruprecht Signed-off-by: Michael Ellerman

powerpc: Remove unused devm_ioremap_prot()

2014-11-09T22:59:28Z

Added in 2008, but has never had any in-tree users, and no other architectures provide it. Signed-off-by: Kyle McMartin Signed-off-by: Michael Ellerman

powerpc: Move lib symbol exports into arch/powerpc/lib/ppc_ksyms.c

2014-09-25T13:14:39Z

Move the lib symbol exports closer to their function definitions Signed-off-by: Anton Blanchard Signed-off-by: Michael Ellerman

powerpc: memcpy optimization for 64bit LE

2014-04-30T05:26:18Z

Unaligned stores take alignment exceptions on POWER7 running in little-endian. This is a dumb little-endian base memcpy that prevents unaligned stores. Once booted the feature fixup code switches over to the VMX copy loops (which are already endian safe). The question is what we do before that switch over. The base 64bit memcpy takes alignment exceptions on POWER7 so we can't use it as is. Fixing the causes of alignment exception would slow it down, because we'd need to ensure all loads and stores are aligned either through rotate tricks or bytewise loads and stores. Either would be bad for all other 64bit platforms. [ I simplified the loop a bit - Anton ] Signed-off-by: Philippe Bergheaud Signed-off-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt

powerpc: Add VMX optimised xor for RAID5

2013-10-30T05:02:28Z

Add a VMX optimised xor, used primarily for RAID5. On a POWER7 blade this is a decent win: 32regs : 17932.800 MB/sec altivec : 19724.800 MB/sec The bigger gain is when the same test is run in SMT4 mode, as it would if there was a lot of work going on: 8regs : 8377.600 MB/sec altivec : 15801.600 MB/sec I tested this against an array created without the patch, and also verified it worked as expected on a little endian kernel. [ Fix !CONFIG_ALTIVEC build -- BenH ] Signed-off-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt

powerpc: Use generic memcpy code in little endian

2013-10-11T05:48:40Z

We need to fix some endian issues in our memcpy code. For now just enable the generic memcpy routine for little endian builds. Signed-off-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt