ptrace and perf watchpoints can't co-exists if their address range
overlaps. See commit 29da4f91c0 ("powerpc/watchpoint: Don't allow
concurrent perf and ptrace events") for more detail. Add selftest
for the same.
Sample o/p:
# ./ptrace-perf-hwbreak
test: ptrace-perf-hwbreak
tags: git_version:powerpc-5.8-7-118-g937fa174a15d-dirty
perf cpu event -> ptrace thread event (Overlapping): Ok
perf cpu event -> ptrace thread event (Non-overlapping): Ok
perf thread event -> ptrace same thread event (Overlapping): Ok
perf thread event -> ptrace same thread event (Non-overlapping): Ok
perf thread event -> ptrace other thread event: Ok
ptrace thread event -> perf kernel event: Ok
ptrace thread event -> perf same thread event (Overlapping): Ok
ptrace thread event -> perf same thread event (Non-overlapping): Ok
ptrace thread event -> perf other thread event: Ok
ptrace thread event -> perf cpu event (Overlapping): Ok
ptrace thread event -> perf cpu event (Non-overlapping): Ok
ptrace thread event -> perf same thread & cpu event (Overlapping): Ok
ptrace thread event -> perf same thread & cpu event (Non-overlapping): Ok
ptrace thread event -> perf other thread & cpu event: Ok
success: ptrace-perf-hwbreak
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210412112218.128183-5-ravi.bangoria@linux.ibm.com
290f7d8ce2