[PATCH v6 00/16] powerpc/watchpoint: Preparation for more than one watchpoint

From: Ravi Bangoria
Date: Thu May 14 2020 - 07:18:27 EST


So far, powerpc Book3S code has been written with an assumption of
only one watchpoint. But Power10[1] is introducing second watchpoint
register (DAWR). Even though this patchset does not enable 2nd DAWR,
it makes 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.

v5: https://lore.kernel.org/linuxppc-dev/20200511025911.212827-1-ravi.bangoria@xxxxxxxxxxxxx

v5->v6:
- Rebased to powerpc/next-test which has prefix-instruction support
- Adopt 'struct ppc_inst' in hw-breakpoint code as well

[1]: https://www-355.ibm.com/systems/power/openpower/

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 | 642 ++++++++++++++++++----
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, 811 insertions(+), 227 deletions(-)

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2.26.2