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. v2: https://lore.kernel.org/linuxppc-dev/20200401061309.92442-1-ravi.bango...@linux.ibm.com v2->v3: - Few minor improvements as suggested by Christophe - 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 | 646 ++++++++++++++++++---- 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 | 12 +- 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