int check_hw_breakpoint()

in kernel/hw_breakpoint.c [276:308]

31 lines of code
10 McCabe index (conditional complexity)


int check_hw_breakpoint(struct pt_regs *regs)
{
	if (regs->debugcause & BIT(DEBUGCAUSE_IBREAK_BIT)) {
		int i;
		struct perf_event **bp = this_cpu_ptr(bp_on_reg);

		for (i = 0; i < XCHAL_NUM_IBREAK; ++i) {
			if (bp[i] && !bp[i]->attr.disabled &&
			    regs->pc == bp[i]->attr.bp_addr)
				perf_bp_event(bp[i], regs);
		}
		return 0;
	} else if (regs->debugcause & BIT(DEBUGCAUSE_DBREAK_BIT)) {
		struct perf_event **bp = this_cpu_ptr(wp_on_reg);
		int dbnum = (regs->debugcause & DEBUGCAUSE_DBNUM_MASK) >>
			DEBUGCAUSE_DBNUM_SHIFT;

		if (dbnum < XCHAL_NUM_DBREAK && bp[dbnum]) {
			if (user_mode(regs)) {
				perf_bp_event(bp[dbnum], regs);
			} else {
				set_thread_flag(TIF_DB_DISABLED);
				xtensa_wsr(0, SREG_DBREAKC + dbnum);
			}
		} else {
			WARN_ONCE(1,
				  "Wrong/unconfigured DBNUM reported in DEBUGCAUSE: %d\n",
				  dbnum);
		}
		return 0;
	}
	return -ENOENT;
}