[PATCH v4 00/16] powerpc/watchpoint: Preparation for more than one watchpoint

[Ravi Bangoria]

So far, powerpc Book3S code has been written with an assumption of only
one watchpoint. But future power architecture is introducing second
watchpoint register (DAWR). Even though this patchset does not enable
2nd DAWR, it make the infrastructure ready so that enabling 2nd DAWR
should just be a matter of changing count.

Existing functionality works fine with the patchset. I've tested it with
perf, ptrace(gdb), xmon. All hw-breakpoint selftests are passing as well.
And I've build tested for 8xx and 'AMCC 44x, 46x or 47x'.

Note: kvm or PowerVM guest is not enabled yet.

v3: https://lore.kernel.org/linuxppc-dev/20200414031659.58875-1-ravi.bangoria@linux.ibm.com

v3->v4:
 - Reduce the scope of local variables to increase readability at some
   places, suggested by Christophe.
 - Added Michael Neuling's Reviewed by for the series.
 - Rebased to powerpc/next

Ravi Bangoria (16):
  powerpc/watchpoint: Rename current DAWR macros
  powerpc/watchpoint: Add SPRN macros for second DAWR
  powerpc/watchpoint: Introduce function to get nr watchpoints
    dynamically
  powerpc/watchpoint/ptrace: Return actual num of available watchpoints
  powerpc/watchpoint: Provide DAWR number to set_dawr
  powerpc/watchpoint: Provide DAWR number to __set_breakpoint
  powerpc/watchpoint: Get watchpoint count dynamically while disabling
    them
  powerpc/watchpoint: Disable all available watchpoints when
    !dawr_force_enable
  powerpc/watchpoint: Convert thread_struct->hw_brk to an array
  powerpc/watchpoint: Use loop for thread_struct->ptrace_bps
  powerpc/watchpoint: Introduce is_ptrace_bp() function
  powerpc/watchpoint: Use builtin ALIGN*() macros
  powerpc/watchpoint: Prepare handler to handle more than one
    watcnhpoint
  powerpc/watchpoint: Don't allow concurrent perf and ptrace events
  powerpc/watchpoint/xmon: Don't allow breakpoint overwriting
  powerpc/watchpoint/xmon: Support 2nd dawr

 arch/powerpc/include/asm/cputable.h       |   6 +-
 arch/powerpc/include/asm/debug.h          |   2 +-
 arch/powerpc/include/asm/hw_breakpoint.h  |  32 +-
 arch/powerpc/include/asm/processor.h      |   6 +-
 arch/powerpc/include/asm/reg.h            |   6 +-
 arch/powerpc/include/asm/sstep.h          |   2 +
 arch/powerpc/kernel/dawr.c                |  23 +-
 arch/powerpc/kernel/hw_breakpoint.c       | 645 ++++++++++++++++++----
 arch/powerpc/kernel/process.c             |  85 +--
 arch/powerpc/kernel/ptrace/ptrace-noadv.c |  72 ++-
 arch/powerpc/kernel/ptrace/ptrace32.c     |   4 +-
 arch/powerpc/kernel/signal.c              |  13 +-
 arch/powerpc/kvm/book3s_hv.c              |  12 +-
 arch/powerpc/kvm/book3s_hv_rmhandlers.S   |  18 +-
 arch/powerpc/xmon/xmon.c                  |  99 +++-
 kernel/events/hw_breakpoint.c             |  16 +
 16 files changed, 814 insertions(+), 227 deletions(-)

-- 
2.21.1