return 0; /* no instruction breakpoints available */
}
-static bool single_step_pending(void)
-{
- int i;
-
- for (i = 0; i < nr_wp_slots(); i++) {
- if (current->thread.last_hit_ubp[i])
- return true;
- }
- return false;
-}
/*
* Install a perf counter breakpoint.
* Do not install DABR values if the instruction must be single-stepped.
* If so, DABR will be populated in single_step_dabr_instruction().
*/
- if (!single_step_pending())
+ if (!info->perf_single_step)
__set_breakpoint(i, info);
return 0;
}
/*
- * Perform cleanup of arch-specific counters during unregistration
- * of the perf-event
- */
-void arch_unregister_hw_breakpoint(struct perf_event *bp)
-{
- /*
- * If the breakpoint is unregistered between a hw_breakpoint_handler()
- * and the single_step_dabr_instruction(), then cleanup the breakpoint
- * restoration variables to prevent dangling pointers.
- * FIXME, this should not be using bp->ctx at all! Sayeth peterz.
- */
- if (bp->ctx && bp->ctx->task && bp->ctx->task != ((void *)-1L)) {
- int i;
-
- for (i = 0; i < nr_wp_slots(); i++) {
- if (bp->ctx->task->thread.last_hit_ubp[i] == bp)
- bp->ctx->task->thread.last_hit_ubp[i] = NULL;
- }
- }
-}
-
-/*
* Check for virtual address in kernel space.
*/
int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw)
int i;
for (i = 0; i < nr_wp_slots(); i++) {
- if (unlikely(tsk->thread.last_hit_ubp[i]))
+ struct perf_event *bp = __this_cpu_read(bp_per_reg[i]);
+
+ if (unlikely(bp && counter_arch_bp(bp)->perf_single_step))
goto reset;
}
return;
for (i = 0; i < nr_wp_slots(); i++) {
info = counter_arch_bp(__this_cpu_read(bp_per_reg[i]));
__set_breakpoint(i, info);
- tsk->thread.last_hit_ubp[i] = NULL;
+ info->perf_single_step = false;
}
}
for (i = 0; i < nr_wp_slots(); i++) {
if (!hit[i])
continue;
- current->thread.last_hit_ubp[i] = bp[i];
+
+ counter_arch_bp(bp[i])->perf_single_step = true;
bp[i] = NULL;
}
regs_set_return_msr(regs, regs->msr | MSR_SE);
static int single_step_dabr_instruction(struct die_args *args)
{
struct pt_regs *regs = args->regs;
- struct perf_event *bp = NULL;
- struct arch_hw_breakpoint *info;
- int i;
bool found = false;
/*
* Check if we are single-stepping as a result of a
* previous HW Breakpoint exception
*/
- for (i = 0; i < nr_wp_slots(); i++) {
- bp = current->thread.last_hit_ubp[i];
+ for (int i = 0; i < nr_wp_slots(); i++) {
+ struct perf_event *bp;
+ struct arch_hw_breakpoint *info;
+
+ bp = __this_cpu_read(bp_per_reg[i]);
if (!bp)
continue;
- found = true;
info = counter_arch_bp(bp);
+ if (!info->perf_single_step)
+ continue;
+
+ found = true;
+
/*
* We shall invoke the user-defined callback function in the
* single stepping handler to confirm to 'trigger-after-execute'
*/
if (!(info->type & HW_BRK_TYPE_EXTRANEOUS_IRQ))
perf_bp_event(bp, regs);
- current->thread.last_hit_ubp[i] = NULL;
+
+ info->perf_single_step = false;
}
if (!found)
return NOTIFY_DONE;
- for (i = 0; i < nr_wp_slots(); i++) {
- bp = __this_cpu_read(bp_per_reg[i]);
+ for (int i = 0; i < nr_wp_slots(); i++) {
+ struct perf_event *bp = __this_cpu_read(bp_per_reg[i]);
if (!bp)
continue;
- info = counter_arch_bp(bp);
- __set_breakpoint(i, info);
+ __set_breakpoint(i, counter_arch_bp(bp));
}
/*