diff options
| -rw-r--r-- | sys/kern/kern_switch.c | 54 |
1 files changed, 22 insertions, 32 deletions
diff --git a/sys/kern/kern_switch.c b/sys/kern/kern_switch.c index 59d9ce0..aa75dab 100644 --- a/sys/kern/kern_switch.c +++ b/sys/kern/kern_switch.c @@ -360,45 +360,35 @@ runq_findbit(struct runq *rq) } static __inline int -runq_findbit_from(struct runq *rq, u_char start) +runq_findbit_from(struct runq *rq, u_char pri) { struct rqbits *rqb; - int bit; - int pri; + rqb_word_t mask; int i; + /* + * Set the mask for the first word so we ignore priorities before 'pri'. + */ + mask = (rqb_word_t)-1 << (pri & (RQB_BPW - 1)); rqb = &rq->rq_status; - bit = start & (RQB_BPW -1); - pri = 0; - CTR1(KTR_RUNQ, "runq_findbit_from: start %d", start); again: - for (i = RQB_WORD(start); i < RQB_LEN; i++) { - CTR3(KTR_RUNQ, "runq_findbit_from: bits %d = %#x bit = %d", - i, rqb->rqb_bits[i], bit); - if (rqb->rqb_bits[i]) { - if (bit != 0) { - for (pri = bit; pri < RQB_BPW; pri++) - if (rqb->rqb_bits[i] & (1ul << pri)) - break; - bit = 0; - if (pri >= RQB_BPW) - continue; - } else - pri = RQB_FFS(rqb->rqb_bits[i]); - pri += (i << RQB_L2BPW); - CTR3(KTR_RUNQ, "runq_findbit_from: bits=%#x i=%d pri=%d", - rqb->rqb_bits[i], i, pri); - return (pri); - } - bit = 0; - } - if (start != 0) { - CTR0(KTR_RUNQ, "runq_findbit_from: restarting"); - start = 0; - goto again; + for (i = RQB_WORD(pri); i < RQB_LEN; mask = -1, i++) { + mask = rqb->rqb_bits[i] & mask; + if (mask == 0) + continue; + pri = RQB_FFS(mask) + (i << RQB_L2BPW); + CTR3(KTR_RUNQ, "runq_findbit_from: bits=%#x i=%d pri=%d", + mask, i, pri); + return (pri); } - - return (-1); + if (pri == 0) + return (-1); + /* + * Wrap back around to the beginning of the list just once so we + * scan the whole thing. + */ + pri = 0; + goto again; } /* |
