Give existing errors priority over the generation of Task
Set Full (TSF) errors. So that max_queue is not exceeded,
existing errors may be sent back in the invocation thread.
This is done so errors like Unit Attentions are not hidden
and lost by either max_queue exceeded or real/injected
TSFs.
Signed-off-by: Douglas Gilbert dgilb...@interlog.com
---
drivers/scsi/scsi_debug.c | 67 +++
1 file changed, 33 insertions(+), 34 deletions(-)
diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 07d224a..693f2fa 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -3006,7 +3006,7 @@ schedule_resp(struct scsi_cmnd *cmnd, struct sdebug_dev_info *devip,
int scsi_result, int delta_jiff)
{
unsigned long iflags;
- int k, num_in_q, tsf, qdepth, inject;
+ int k, num_in_q, qdepth, inject;
struct sdebug_queued_cmd *sqcp = NULL;
struct scsi_device *sdp = cmnd-device;
@@ -3019,55 +3019,48 @@ schedule_resp(struct scsi_cmnd *cmnd, struct sdebug_dev_info *devip,
if ((scsi_result) (SCSI_DEBUG_OPT_NOISE scsi_debug_opts))
sdev_printk(KERN_INFO, sdp, %s: non-zero result=0x%x\n,
__func__, scsi_result);
- if (delta_jiff == 0) {
- /* using same thread to call back mid-layer */
- cmnd-result = scsi_result;
- cmnd-scsi_done(cmnd);
- return 0;
- }
+ if (delta_jiff == 0)
+ goto respond_in_thread;
- /* deferred response cases */
+ /* schedule the response at a later time if resources permit */
spin_lock_irqsave(queued_arr_lock, iflags);
num_in_q = atomic_read(devip-num_in_q);
qdepth = cmnd-device-queue_depth;
- k = find_first_zero_bit(queued_in_use_bm, scsi_debug_max_queue);
- tsf = 0;
inject = 0;
- if ((qdepth 0) (num_in_q = qdepth))
- tsf = 1;
- else if ((scsi_debug_every_nth != 0)
- (SCSI_DEBUG_OPT_RARE_TSF scsi_debug_opts)) {
+ if ((qdepth 0) (num_in_q = qdepth)) {
+ if (scsi_result) {
+ spin_unlock_irqrestore(queued_arr_lock, iflags);
+ goto respond_in_thread;
+ } else
+ scsi_result = device_qfull_result;
+ } else if ((scsi_debug_every_nth != 0)
+ (SCSI_DEBUG_OPT_RARE_TSF scsi_debug_opts)
+ (scsi_result == 0)) {
if ((num_in_q == (qdepth - 1))
(atomic_inc_return(sdebug_a_tsf) =
abs(scsi_debug_every_nth))) {
atomic_set(sdebug_a_tsf, 0);
inject = 1;
- tsf = 1;
+ scsi_result = device_qfull_result;
}
}
- /* if (tsf) simulate device reporting SCSI status of TASK SET FULL.
- * Might override existing CHECK CONDITION. */
- if (tsf)
- scsi_result = device_qfull_result;
+ k = find_first_zero_bit(queued_in_use_bm, scsi_debug_max_queue);
if (k = scsi_debug_max_queue) {
- if (SCSI_DEBUG_OPT_ALL_TSF scsi_debug_opts)
- tsf = 1;
spin_unlock_irqrestore(queued_arr_lock, iflags);
+ if (scsi_result)
+ goto respond_in_thread;
+ else if (SCSI_DEBUG_OPT_ALL_TSF scsi_debug_opts)
+ scsi_result = device_qfull_result;
if (SCSI_DEBUG_OPT_Q_NOISE scsi_debug_opts)
sdev_printk(KERN_INFO, sdp,
-%s: num_in_q=%d, bypass q, %s%s\n,
-__func__, num_in_q,
-(inject ? inject : ),
-(tsf ? status: TASK SET FULL :
- report: host busy));
- if (tsf) {
- /* queued_arr full so respond in same thread */
- cmnd-result = scsi_result;
- cmnd-scsi_done(cmnd);
- /* As scsi_done() is called inline must return 0 */
- return 0;
- } else
+%s: max_queue=%d exceeded, %s\n,
+__func__, scsi_debug_max_queue,
+(scsi_result ? status: TASK SET FULL :
+ report: host busy));
+ if (scsi_result)
+ goto respond_in_thread;
+ else
return SCSI_MLQUEUE_HOST_BUSY;
}
__set_bit(k, queued_in_use_bm);
@@ -3117,12 +3110,18 @@ schedule_resp(struct scsi_cmnd *cmnd, struct sdebug_dev_info *devip,
else
tasklet_schedule(sqcp-tletp);
}
- if (tsf (SCSI_DEBUG_OPT_Q_NOISE scsi_debug_opts))
+ if ((SCSI_DEBUG_OPT_Q_NOISE scsi_debug_opts)
+ (scsi_result == device_qfull_result))
sdev_printk(KERN_INFO, sdp,
%s: num_in_q=%d +1, %s%s\n, __func__,
num_in_q, (inject ? inject : ),
status: TASK SET FULL);
return 0;
+
+respond_in_thread: /* call back to mid-layer using invocation thread */
+ cmnd-result = scsi_result;
+ cmnd-scsi_done(cmnd);
+ return 0;
}
/* Note: The following macros create attribute files in the
--
1.9.1
