Will Deacon 93a04a3416 ARM: hw_breakpoint: do not allocate new breakpoints with preemption disabled ... The watchpoint single-stepping code calls register_user_hw_breakpoint to register a mismatch breakpoint for stepping over the watchpoint. This is performed with preemption disabled, which is unsafe as we may end up scheduling whilst in_atomic(). Furthermore, using the perf API is rather overkill since we are already in the hw-breakpoint backend and only require access to reserved breakpoints anyway. This patch reworks the watchpoint stepping code so that we don't require another perf_event for the mismatch breakpoint. Instead, we hold a separate arch_hw_breakpoint_ctrl struct inside the watchpoint which is used exclusively for stepping. We can check whether or not stepping is enabled when installing or uninstalling the watchpoint and operate on the breakpoint accordingly. Signed-off-by: Will Deacon <will.deacon@arm.com>		2010-12-06 11:55:57 +00:00
..
asm	ARM: hw_breakpoint: do not allocate new breakpoints with preemption disabled	2010-12-06 11:55:57 +00:00