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  1. 30 Jan, 2015 28 commits
  3. 28 Jan, 2015 7 commits
  5. 27 Jan, 2015 2 commits
    • Pranith Kumar's avatar
      powerpc/powernv: Skip registering log region when CONFIG_PRINTK=n · 6501ab5e
      Pranith Kumar authored 
      When CONFIG_PRINTK=n, log_buf_addr_get() returns NULL and log_buf_len_get()
return 0. Check for these return values and skip registering the dump buffer.
Signed-off-by: default avatarPranith Kumar <bobby.prani@gmail.com>
Reviewed-by: default avatarStewart Smith <stewart@linux.vnet.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      6501ab5e
    • Cyril Bur's avatar
      powerpc/pseries: Fix endian problems with LE migration · 3df76a9d
      Cyril Bur authored 
      RTAS events require arguments be passed in big endian while hypercalls
have their arguments passed in registers and the values should therefore
be in CPU endian.

The "ibm,suspend_me" 'RTAS' call makes a sequence of hypercalls to setup
one true RTAS call. This means that "ibm,suspend_me" is handled
specially in the ppc_rtas() syscall.

The ppc_rtas() syscall has its arguments in big endian and can therefore
pass these arguments directly to the RTAS call. "ibm,suspend_me" is
handled specially from within ppc_rtas() (by calling rtas_ibm_suspend_me())
which has left an endian bug on little endian systems due to the
requirement of hypercalls. The return value from rtas_ibm_suspend_me()
gets returned in cpu endian, and is left unconverted, also a bug on
little endian systems.

rtas_ibm_suspend_me() does not actually make use of the rtas_args that
it is passed. This patch removes the convoluted use of the rtas_args
struct to pass params to rtas_ibm_suspend_me() in favour of passing what
it needs as actual arguments. This patch also ensures the two callers of
rtas_ibm_suspend_me() pass function parameters in cpu endian and in the
case of ppc_rtas(), converts the return value.

migrate_store() (the other caller of rtas_ibm_suspend_me()) is from a
sysfs file which deals with everything in cpu endian so this function
only underwent cleanup.

This patch has been tested with KVM both LE and BE and on PowerVM both
LE and BE. Under QEMU/KVM the migration happens without touching these
code pathes.

For PowerVM there is no obvious regression on BE and the LE code path
now provides the correct parameters to the hypervisor.
Signed-off-by: default avatarCyril Bur <cyrilbur@gmail.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      3df76a9d
  7. 23 Jan, 2015 3 commits
    • Anton Blanchard's avatar
      selftests/powerpc: Add memcmp testcase · 521adf53
      Anton Blanchard authored 
      Add a testcase for the new ppc64 memcmp.
Signed-off-by: default avatarAnton Blanchard <anton@samba.org>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      521adf53
    • Anton Blanchard's avatar
      powerpc: Add 64bit optimised memcmp · 15c2d45d
      Anton Blanchard authored 
      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: default avatarAnton Blanchard <anton@samba.org>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      15c2d45d
    • Gavin Shan's avatar
      powerpc/powernv: Remove pnv_pci_probe_mode() · a113de37
      Gavin Shan authored 
      The callback (ppc_md.pci_probe_mode()) is used to determine if the
child PCI devices of the indicated PCI bus should be probed from
device-tree or hardware. On PowerNV platform, we always expect
probing PCI devices from hardware, which is PowerPC PCI core's
default behaviour. Also, the callback had some delay implemented
based on PHB's device node property "reset-clear-timestamp", which
wasn't exported from skiboot. So we don't need this function and
it's safe to remove it.
Signed-off-by: default avatarGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      a113de37
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