1. 15 Sep, 2008 3 commits
    • Mark Nelson's avatar
      powerpc: New copy_4K_page() · 57dda6ef
      Mark Nelson authored
      This new copy_4K_page() function was originally tuned for the best
      performance on the Cell processor, but after testing on more 64bit
      powerpc chips it was found that with a small modification it either
      matched the performance offered by the current mainline version or
      bettered it by a small amount.
      
      It was found that on a Cell-based QS22 blade the amount of system
      time measured when compiling a 2.6.26 pseries_defconfig decreased
      by 4%. Using the same test, a 4-way 970MP machine saw a decrease of
      2% in system time. No noticeable change was seen on Power4, Power5
      or Power6.
      
      The 4096 byte page is copied in thirty-two 128 byte strides. An
      initial setup loop executes dcbt instructions for the whole source
      page and dcbz instructions for the whole destination page. To do
      this, the cache line size is retrieved from ppc64_caches.
      
      A new CPU feature bit, CPU_FTR_CP_USE_DCBTZ, (introduced in the
      previous patch) is used to make the modification to this new copy
      routine - on Power4, 970 and Cell the feature bit is set so the
      setup loop is executed, but on all other 64bit chips the setup
      loop is nop'ed out.
      Signed-off-by: default avatarMark Nelson <markn@au1.ibm.com>
      Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      57dda6ef
    • Mark Nelson's avatar
      powerpc: Add new CPU feature: CPU_FTR_CP_USE_DCBTZ · 2a929436
      Mark Nelson authored
      Add a new CPU feature bit, CPU_FTR_CP_USE_DCBTZ, to be added to the
      64bit powerpc chips that benefit from having dcbt and dcbz
      instructions used in their memory copy routines.
      
      This will be used in a subsequent patch that updates copy_4K_page().
      The new bit is added to Cell, PPC970 and Power4 because they show
      better performance with the new copy_4K_page() when dcbt and dcbz
      instructions are used.
      Signed-off-by: default avatarMark Nelson <markn@au1.ibm.com>
      Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      2a929436
    • roel kluin's avatar
      powerpc: Fix duplicate test of MACIO_FLAG_SCCB_ON · 1b3c83e6
      roel kluin authored
      Evidently MACIO_FLAG_SCCA_ON was meant.
      Signed-off-by: default avatarRoel Kluin <roel.kluin@gmail.com>
      Acked-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
      Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      1b3c83e6
  2. 10 Sep, 2008 1 commit
  3. 09 Sep, 2008 12 commits
  4. 08 Sep, 2008 24 commits