BMC/Intel-BMC/linux.git/arch/powerpc/lib/string_64.S, branch dev-4.10

powerpc: EX_TABLE macro for exception tables

2016-11-14T00:11:51+00:00

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 Signed-off-by: Michael Ellerman

ppc: move exports to definitions

2016-08-08T03:50:09+00:00

Signed-off-by: Al Viro

powerpc: Exported functions __clear_user and copy_page use r2 so need _GLOBAL_TOC()

2014-06-05T03:20:41+00:00

__clear_user and copy_page load from the TOC and are also exported to modules. This means we have to use _GLOBAL_TOC() so that we create the global entry point that sets up the TOC. Signed-off-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt

powerpc: Optimise the 64bit optimised __clear_user

2012-07-03T04:14:48+00:00

I blame Mikey for this. He elevated my slightly dubious testcase: to benchmark status. And naturally we need to be number 1 at creating zeros. So lets improve __clear_user some more. As Paul suggests we can use dcbz for large lengths. This patch gets the destination cacheline aligned then uses dcbz on whole cachelines. Before: 10485760000 bytes (10 GB) copied, 0.414744 s, 25.3 GB/s After: 10485760000 bytes (10 GB) copied, 0.268597 s, 39.0 GB/s 39 GB/s, a new record. Signed-off-by: Anton Blanchard Tested-by: Olof Johansson Acked-by: Olof Johansson Signed-off-by: Benjamin Herrenschmidt

powerpc: 64bit optimised __clear_user

2012-07-03T04:14:41+00:00

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 Signed-off-by: Benjamin Herrenschmidt