From b66229258f88a06ecdb8998066861b3ad8ad6a2a Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Sun, 9 Sep 2007 08:56:31 -0600 Subject: [PATCH] [SCSI] advansys: Remove `waiting' queue If the adapter is busy, return the request to the midlayer rather than queueing it in the driver. asc_execute_queue() and asc_dequeue() become unused, and we don't need to print out stats on the waiting queue any more. Signed-off-by: Matthew Wilcox Signed-off-by: James Bottomley --- drivers/scsi/advansys.c | 186 +++--------------------------------------------- 1 file changed, 9 insertions(+), 177 deletions(-) diff --git a/drivers/scsi/advansys.c b/drivers/scsi/advansys.c index fe289b1..526239a 100644 --- a/drivers/scsi/advansys.c +++ b/drivers/scsi/advansys.c @@ -2852,7 +2852,6 @@ typedef struct asc_board { } dvc_cfg; ushort asc_n_io_port; /* Number I/O ports. */ asc_queue_t active; /* Active command queue */ - asc_queue_t waiting; /* Waiting command queue */ asc_queue_t done; /* Done command queue */ ADV_SCSI_BIT_ID_TYPE init_tidmask; /* Target init./valid mask */ struct scsi_device *device[ADV_MAX_TID + 1]; /* Mid-Level Scsi Device */ @@ -2922,10 +2921,8 @@ static int asc_build_req(asc_board_t *, struct scsi_cmnd *); static int adv_build_req(asc_board_t *, struct scsi_cmnd *, ADV_SCSI_REQ_Q **); static int adv_get_sglist(asc_board_t *, adv_req_t *, struct scsi_cmnd *, int); static void asc_enqueue(asc_queue_t *, REQP, int); -static REQP asc_dequeue(asc_queue_t *, int); static REQP asc_dequeue_list(asc_queue_t *, REQP *, int); static int asc_rmqueue(asc_queue_t *, REQP); -static void asc_execute_queue(asc_queue_t *); #ifdef CONFIG_PROC_FS static int asc_proc_copy(off_t, off_t, char *, int, char *, int); static int asc_prt_board_devices(struct Scsi_Host *, char *, int); @@ -3274,6 +3271,7 @@ advansys_queuecommand(struct scsi_cmnd *scp, void (*done) (struct scsi_cmnd *)) asc_board_t *boardp; ulong flags; struct scsi_cmnd *done_scp; + int asc_res, result = 0; shost = scp->device->host; boardp = ASC_BOARDP(shost); @@ -3302,37 +3300,13 @@ advansys_queuecommand(struct scsi_cmnd *scp, void (*done) (struct scsi_cmnd *)) return 0; } - /* - * Attempt to execute any waiting commands for the board. - */ - if (!ASC_QUEUE_EMPTY(&boardp->waiting)) { - ASC_DBG(1, - "advansys_queuecommand: before asc_execute_queue() waiting\n"); - asc_execute_queue(&boardp->waiting); - } - - /* - * Save the function pointer to Linux mid-level 'done' function - * and attempt to execute the command. - * - * If ASC_NOERROR is returned the request has been added to the - * board's 'active' queue and will be completed by the interrupt - * handler. - * - * If ASC_BUSY is returned add the request to the board's per - * target waiting list. This is the first time the request has - * been tried. Add it to the back of the waiting list. It will be - * retried later. - * - * If an error occurred, the request will have been placed on the - * board's 'done' queue and must be completed before returning. - */ scp->scsi_done = done; - switch (asc_execute_scsi_cmnd(scp)) { + asc_res = asc_execute_scsi_cmnd(scp); + switch (asc_res) { case ASC_NOERROR: break; case ASC_BUSY: - asc_enqueue(&boardp->waiting, scp, ASC_BACK); + result = SCSI_MLQUEUE_HOST_BUSY; break; case ASC_ERROR: default: @@ -3343,7 +3317,7 @@ advansys_queuecommand(struct scsi_cmnd *scp, void (*done) (struct scsi_cmnd *)) } spin_unlock_irqrestore(&boardp->lock, flags); - return 0; + return result; } /* @@ -3488,33 +3462,6 @@ static int advansys_reset(struct scsi_cmnd *scp) } } - /* - * Dequeue all 'waiting' requests and set the request status - * to DID_RESET. - */ - if (done_scp == NULL) { - done_scp = asc_dequeue_list(&boardp->waiting, &last_scp, - ASC_TID_ALL); - for (tscp = done_scp; tscp; tscp = REQPNEXT(tscp)) { - tscp->result = HOST_BYTE(DID_RESET); - } - } else { - /* Append to 'done_scp' at the end with 'last_scp'. */ - ASC_ASSERT(last_scp != NULL); - last_scp->host_scribble = - (unsigned char *)asc_dequeue_list(&boardp->waiting, - &new_last_scp, - ASC_TID_ALL); - if (new_last_scp != NULL) { - ASC_ASSERT(REQPNEXT(last_scp) != NULL); - for (tscp = REQPNEXT(last_scp); tscp; - tscp = REQPNEXT(tscp)) { - tscp->result = HOST_BYTE(DID_RESET); - } - last_scp = new_last_scp; - } - } - /* Save the time of the most recently completed reset. */ boardp->last_reset = jiffies; @@ -3650,7 +3597,7 @@ static irqreturn_t advansys_interrupt(int irq, void *dev_id) } /* - * Start waiting requests and create a list of completed requests. + * Create a list of completed requests. * * If a reset request is being performed for the board, the reset * handler will complete pending requests after it has completed. @@ -3659,13 +3606,6 @@ static irqreturn_t advansys_interrupt(int irq, void *dev_id) ASC_DBG2(1, "advansys_interrupt: done_scp 0x%p, " "last_scp 0x%p\n", done_scp, last_scp); - /* Start any waiting commands for the board. */ - if (!ASC_QUEUE_EMPTY(&boardp->waiting)) { - ASC_DBG(1, "advansys_interrupt: before " - "asc_execute_queue()\n"); - asc_execute_queue(&boardp->waiting); - } - /* * Add to the list of requests that must be completed. * @@ -3986,8 +3926,8 @@ static void asc_scsi_done_list(struct scsi_cmnd *scp) * If this function returns ASC_NOERROR the request has been enqueued * on the board's 'done' queue and must be completed by the caller. * - * If ASC_BUSY is returned the request will be enqueued by the - * caller on the target's waiting queue and re-tried later. + * If ASC_BUSY is returned the request will be returned to the midlayer + * and re-tried later. */ static int asc_execute_scsi_cmnd(struct scsi_cmnd *scp) { @@ -4043,10 +3983,6 @@ static int asc_execute_scsi_cmnd(struct scsi_cmnd *scp) "ASC_NOERROR\n"); break; case ASC_BUSY: - /* - * Caller will enqueue request on the target's waiting - * queue and retry later. - */ ASC_STATS(scp->device->host, exe_busy); break; case ASC_ERROR: @@ -4087,10 +4023,6 @@ static int asc_execute_scsi_cmnd(struct scsi_cmnd *scp) ASC_DBG(1, "asc_execute_scsi_cmnd: adv_build_req " "ASC_BUSY\n"); /* - * If busy is returned the request has not been - * enqueued. It will be enqueued by the caller on the - * target's waiting queue and retried later. - * * The asc_stats fields 'adv_build_noreq' and * 'adv_build_nosg' count wide board busy conditions. * They are updated in adv_build_req and @@ -4127,10 +4059,6 @@ static int asc_execute_scsi_cmnd(struct scsi_cmnd *scp) "ASC_NOERROR\n"); break; case ASC_BUSY: - /* - * Caller will enqueue request on the target's waiting - * queue and retry later. - */ ASC_STATS(scp->device->host, exe_busy); break; case ASC_ERROR: @@ -5005,39 +4933,6 @@ static void asc_enqueue(asc_queue_t *ascq, REQP reqp, int flag) } /* - * Return first queued 'REQP' on the specified queue for - * the specified target device. Clear the 'tidmask' bit for - * the device if no more commands are left queued for it. - * - * 'REQPNEXT(reqp)' returns reqp's next pointer. - */ -static REQP asc_dequeue(asc_queue_t *ascq, int tid) -{ - REQP reqp; - - ASC_DBG2(3, "asc_dequeue: ascq 0x%lx, tid %d\n", (ulong)ascq, tid); - ASC_ASSERT(tid >= 0 && tid <= ADV_MAX_TID); - if ((reqp = ascq->q_first[tid]) != NULL) { - ASC_ASSERT(ascq->q_tidmask & ADV_TID_TO_TIDMASK(tid)); - ascq->q_first[tid] = REQPNEXT(reqp); - /* If the queue is empty, clear its bit and the last pointer. */ - if (ascq->q_first[tid] == NULL) { - ascq->q_tidmask &= ~ADV_TID_TO_TIDMASK(tid); - ASC_ASSERT(ascq->q_last[tid] == reqp); - ascq->q_last[tid] = NULL; - } -#ifdef ADVANSYS_STATS - /* Maintain request queue statistics. */ - ascq->q_cur_cnt[tid]--; - ASC_ASSERT(ascq->q_cur_cnt[tid] >= 0); - REQTIMESTAT("asc_dequeue", ascq, reqp, tid); -#endif /* ADVANSYS_STATS */ - } - ASC_DBG1(3, "asc_dequeue: reqp 0x%lx\n", (ulong)reqp); - return reqp; -} - -/* * Return a pointer to a singly linked list of all the requests queued * for 'tid' on the 'asc_queue_t' pointed to by 'ascq'. * @@ -5202,45 +5097,6 @@ static int asc_rmqueue(asc_queue_t *ascq, REQP reqp) return ret; } -/* - * Execute as many queued requests as possible for the specified queue. - * - * Calls asc_execute_scsi_cmnd() to execute a REQP/struct scsi_cmnd. - */ -static void asc_execute_queue(asc_queue_t *ascq) -{ - ADV_SCSI_BIT_ID_TYPE scan_tidmask; - REQP reqp; - int i; - - ASC_DBG1(1, "asc_execute_queue: ascq 0x%lx\n", (ulong)ascq); - /* - * Execute queued commands for devices attached to - * the current board in round-robin fashion. - */ - scan_tidmask = ascq->q_tidmask; - do { - for (i = 0; i <= ADV_MAX_TID; i++) { - if (scan_tidmask & ADV_TID_TO_TIDMASK(i)) { - if ((reqp = asc_dequeue(ascq, i)) == NULL) { - scan_tidmask &= ~ADV_TID_TO_TIDMASK(i); - } else - if (asc_execute_scsi_cmnd - ((struct scsi_cmnd *)reqp) - == ASC_BUSY) { - scan_tidmask &= ~ADV_TID_TO_TIDMASK(i); - /* - * The request returned ASC_BUSY. Enqueue at the front of - * target's waiting list to maintain correct ordering. - */ - asc_enqueue(ascq, reqp, ASC_FRONT); - } - } - } - } while (scan_tidmask); - return; -} - #ifdef CONFIG_PROC_FS /* * asc_prt_board_devices() @@ -6723,7 +6579,6 @@ asc_prt_target_stats(struct Scsi_Host *shost, int tgt_id, char *cp, int cplen) ushort chip_scsi_id; asc_board_t *boardp; asc_queue_t *active; - asc_queue_t *waiting; leftlen = cplen; totlen = len = 0; @@ -6732,7 +6587,6 @@ asc_prt_target_stats(struct Scsi_Host *shost, int tgt_id, char *cp, int cplen) s = &boardp->asc_stats; active = &ASC_BOARDP(shost)->active; - waiting = &ASC_BOARDP(shost)->waiting; if (ASC_NARROW_BOARD(boardp)) { chip_scsi_id = boardp->dvc_cfg.asc_dvc_cfg.chip_scsi_id; @@ -6746,8 +6600,7 @@ asc_prt_target_stats(struct Scsi_Host *shost, int tgt_id, char *cp, int cplen) } do { - if (active->q_tot_cnt[tgt_id] > 0 - || waiting->q_tot_cnt[tgt_id] > 0) { + if (active->q_tot_cnt[tgt_id] > 0) { len = asc_prt_line(cp, leftlen, " target %d\n", tgt_id); ASC_PRT_NEXT(); @@ -6771,27 +6624,6 @@ asc_prt_target_stats(struct Scsi_Host *shost, int tgt_id, char *cp, int cplen) q_tot_cnt [tgt_id])); ASC_PRT_NEXT(); - - len = asc_prt_line(cp, leftlen, - " waiting: cnt [cur %d, max %d, tot %u], time [min %u, max %u, avg %lu.%01lu]\n", - waiting->q_cur_cnt[tgt_id], - waiting->q_max_cnt[tgt_id], - waiting->q_tot_cnt[tgt_id], - waiting->q_min_tim[tgt_id], - waiting->q_max_tim[tgt_id], - (waiting->q_tot_cnt[tgt_id] == - 0) ? 0 : (waiting-> - q_tot_tim[tgt_id] / - waiting-> - q_tot_cnt[tgt_id]), - (waiting->q_tot_cnt[tgt_id] == - 0) ? 0 : ASC_TENTHS(waiting-> - q_tot_tim - [tgt_id], - waiting-> - q_tot_cnt - [tgt_id])); - ASC_PRT_NEXT(); } } while (0); -- 1.8.2.3