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Commit | Line | Data |
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1 | From: Mike Reed <mdr@sgi.com> | |
2 | Subject: qla2xxx: Conditionally disable queue_full tracking | |
3 | References: bnc#449386 | |
4 | ||
5 | Changing a lun's queue depth (/sys/block/sdX/device/queue_depth) isn't | |
6 | sticky when the device is connected via a QLogic fibre channel adapter. | |
7 | ||
8 | The QLogic qla2xxx fibre channel driver dynamically adjusts a lun's queue | |
9 | depth. If a user has a specific need to limit the number of commands issued | |
10 | to a lun (say a tape drive, or a shared raid where the total commands issued | |
11 | to all luns is limited at the controller level, for example) and writes a | |
12 | limiting value to /sys/block/sdXX/device/queue_depth, the qla2xxx driver will | |
13 | silently and gradually increase the queue depth back to the driver limit | |
14 | of ql2xmaxqdepth. While reducing this value (module parameter) or increasing | |
15 | the interval between ramp ups (ql2xqfullrampup) offers the potential for a | |
16 | work around it would be better to have the option of just disabling the | |
17 | dynamic adjustment of queue depth. | |
18 | ||
19 | This patch implements an "off switch" as a module parameter. Applies to | |
20 | 2.6.28-rc6-git1. | |
21 | ||
22 | Signed-off-by: Michael Reed <mdr@sgi.com> | |
23 | Signed-off-by: Hannes Reinecke <hare@suse.de> | |
24 | ||
25 | --- | |
26 | drivers/scsi/qla2xxx/qla_gbl.h | 1 + | |
27 | drivers/scsi/qla2xxx/qla_isr.c | 10 ++++++++++ | |
28 | drivers/scsi/qla2xxx/qla_os.c | 8 ++++++++ | |
29 | 3 files changed, 19 insertions(+) | |
30 | ||
31 | --- a/drivers/scsi/qla2xxx/qla_gbl.h | |
32 | +++ b/drivers/scsi/qla2xxx/qla_gbl.h | |
33 | @@ -63,6 +63,7 @@ extern int ql2xallocfwdump; | |
34 | extern int ql2xextended_error_logging; | |
35 | extern int ql2xqfullrampup; | |
36 | extern int ql2xiidmaenable; | |
37 | +extern int ql2xqfulltracking; | |
38 | ||
39 | extern int qla2x00_loop_reset(scsi_qla_host_t *); | |
40 | extern void qla2x00_abort_all_cmds(scsi_qla_host_t *, int); | |
41 | --- a/drivers/scsi/qla2xxx/qla_isr.c | |
42 | +++ b/drivers/scsi/qla2xxx/qla_isr.c | |
43 | @@ -691,6 +691,9 @@ qla2x00_adjust_sdev_qdepth_up(struct scs | |
44 | { | |
45 | fc_port_t *fcport = data; | |
46 | ||
47 | + if (!ql2xqfulltracking) | |
48 | + return; | |
49 | + | |
50 | if (fcport->ha->max_q_depth <= sdev->queue_depth) | |
51 | return; | |
52 | ||
53 | @@ -729,6 +732,9 @@ qla2x00_ramp_up_queue_depth(scsi_qla_hos | |
54 | fc_port_t *fcport; | |
55 | struct scsi_device *sdev; | |
56 | ||
57 | + if (!ql2xqfulltracking) | |
58 | + return; | |
59 | + | |
60 | sdev = sp->cmd->device; | |
61 | if (sdev->queue_depth >= ha->max_q_depth) | |
62 | return; | |
63 | @@ -1043,6 +1049,8 @@ qla2x00_status_entry(scsi_qla_host_t *ha | |
64 | scsi_status)); | |
65 | ||
66 | /* Adjust queue depth for all luns on the port. */ | |
67 | + if (!ql2xqfulltracking) | |
68 | + break; | |
69 | fcport->last_queue_full = jiffies; | |
70 | starget_for_each_device(cp->device->sdev_target, | |
71 | fcport, qla2x00_adjust_sdev_qdepth_down); | |
72 | @@ -1102,6 +1110,8 @@ qla2x00_status_entry(scsi_qla_host_t *ha | |
73 | * Adjust queue depth for all luns on the | |
74 | * port. | |
75 | */ | |
76 | + if (!ql2xqfulltracking) | |
77 | + break; | |
78 | fcport->last_queue_full = jiffies; | |
79 | starget_for_each_device( | |
80 | cp->device->sdev_target, fcport, | |
81 | --- a/drivers/scsi/qla2xxx/qla_os.c | |
82 | +++ b/drivers/scsi/qla2xxx/qla_os.c | |
83 | @@ -79,6 +79,14 @@ module_param(ql2xmaxqdepth, int, S_IRUGO | |
84 | MODULE_PARM_DESC(ql2xmaxqdepth, | |
85 | "Maximum queue depth to report for target devices."); | |
86 | ||
87 | +int ql2xqfulltracking = 1; | |
88 | +module_param(ql2xqfulltracking, int, S_IRUGO|S_IWUSR); | |
89 | +MODULE_PARM_DESC(ql2xqfulltracking, | |
90 | + "Controls whether the driver tracks queue full status " | |
91 | + "returns and dynamically adjusts a scsi device's queue " | |
92 | + "depth. Default is 1, perform tracking. Set to 0 to " | |
93 | + "disable dynamic tracking and adjustment of queue depth."); | |
94 | + | |
95 | int ql2xqfullrampup = 120; | |
96 | module_param(ql2xqfullrampup, int, S_IRUGO|S_IWUSR); | |
97 | MODULE_PARM_DESC(ql2xqfullrampup, |