Adding module parameters to configure max sectors per request & # of cmds per lun.
Signed-off-by: Bo Yang <[email protected]>
---
drivers/scsi/megaraid/megaraid_sas.c | 94 ++++++++++++++++++++++++-
drivers/scsi/megaraid/megaraid_sas.h | 2
2 files changed, 94 insertions(+), 2 deletions(-)
diff -uprN linux-2.6.22_orig/drivers/scsi/megaraid/megaraid_sas.c linux-2.6.22_new/drivers/scsi/megaraid/megaraid_sas.c
--- linux-2.6.22_orig/drivers/scsi/megaraid/megaraid_sas.c 2007-09-26 13:30:36.000000000 -0700
+++ linux-2.6.22_new/drivers/scsi/megaraid/megaraid_sas.c 2007-09-27 20:37:11.000000000 -0700
@@ -62,6 +62,23 @@ MODULE_PARM_DESC(fast_load,
"megasas: Faster loading of the driver, skips physical devices! \
(default = 0)");
+/*
+ * Number of sectors per IO command will be set in megasas_init_mfi
+ * if user does not provide
+ */
+static unsigned int max_sectors;
+module_param_named(max_sectors, max_sectors, int, 0);
+MODULE_PARM_DESC(max_sectors,
+ "Maximum number of sectors per IO command");
+
+/*
+ * Number of cmds per logical unit
+ */
+static unsigned int cmd_per_lun = MEGASAS_DEFAULT_CMD_PER_LUN;
+module_param_named(cmd_per_lun, cmd_per_lun, int, 0);
+MODULE_PARM_DESC(cmd_per_lun,
+ "Maximum number of commands per logical unit (default=128)");
+
MODULE_LICENSE("GPL");
MODULE_VERSION(MEGASAS_VERSION);
MODULE_AUTHOR("[email protected]");
@@ -2301,6 +2318,31 @@ static int megasas_start_aen(struct mega
class_locale.word);
}
+static ssize_t
+sysfs_max_sectors_read(struct kobject *kobj,
+ struct bin_attribute *bin_attr,
+ char *buf, loff_t off, size_t count)
+{
+ struct Scsi_Host *host = class_to_shost(container_of(kobj,
+ struct class_device, kobj));
+ struct megasas_instance *instance =
+ (struct megasas_instance *)host->hostdata;
+
+ count = sprintf(buf, "%u\n", instance->max_sectors_per_req);
+
+ return count+1;
+}
+
+static struct bin_attribute sysfs_max_sectors_attr = {
+ .attr = {
+ .name = "max_sectors",
+ .mode = S_IRUSR|S_IRGRP|S_IROTH,
+ .owner = THIS_MODULE,
+ },
+ .size = 7,
+ .read = sysfs_max_sectors_read,
+};
+
/**
* megasas_io_attach - Attaches this driver to SCSI mid-layer
* @instance: Adapter soft state
@@ -2308,17 +2350,48 @@ static int megasas_start_aen(struct mega
static int megasas_io_attach(struct megasas_instance *instance)
{
struct Scsi_Host *host = instance->host;
+ int error;
/*
- * Export parameters required by SCSI mid-layer
+ * Export host parameters required by SCSI
+ * mid-layer
*/
host->irq = instance->pdev->irq;
host->unique_id = instance->unique_id;
host->can_queue = instance->max_fw_cmds - MEGASAS_INT_CMDS;
host->this_id = instance->init_id;
host->sg_tablesize = instance->max_num_sge;
+
+ /*
+ * Check if the module parameter value for max_sectors can be used
+ */
+ if (max_sectors && max_sectors <= instance->max_sectors_per_req)
+ instance->max_sectors_per_req = max_sectors;
+ else {
+ if (max_sectors)
+ printk(KERN_INFO
+ "megasas: max_sectors should be > 0 and"
+ "<= %d\n",
+ instance->max_sectors_per_req);
+ }
+
host->max_sectors = instance->max_sectors_per_req;
- host->cmd_per_lun = 128;
+
+ /*
+ * Check if the module parameter value for cmd_per_lun can be used
+ */
+ instance->cmd_per_lun = MEGASAS_DEFAULT_CMD_PER_LUN;
+ if (cmd_per_lun && cmd_per_lun <= MEGASAS_DEFAULT_CMD_PER_LUN)
+ instance->cmd_per_lun = cmd_per_lun;
+ else
+ printk(KERN_INFO "megasas: cmd_per_lun should be > 0 and"
+ "<= %d\n", MEGASAS_DEFAULT_CMD_PER_LUN);
+
+ host->cmd_per_lun = instance->cmd_per_lun;
+
+ printk(KERN_DEBUG "megasas: max_sectors : 0x%x, cmd_per_lun : 0x%x\n",
+ instance->max_sectors_per_req, instance->cmd_per_lun);
+
host->max_channel = MEGASAS_MAX_CHANNELS - 1;
host->max_id = MEGASAS_MAX_DEV_PER_CHANNEL;
host->max_lun = MEGASAS_MAX_LUN;
@@ -2333,10 +2406,25 @@ static int megasas_io_attach(struct mega
}
/*
+ * Create sysfs entries for module paramaters
+ */
+ error = sysfs_create_bin_file(&instance->host->shost_classdev.kobj,
+ &sysfs_max_sectors_attr);
+ if (error) {
+ printk(KERN_INFO "megasas: Error in creating the sysfs entry"
+ " max_sectors.\n");
+ goto out_remove_host;
+ }
+
+ /*
* Trigger SCSI to scan our drives
*/
scsi_scan_host(host);
return 0;
+
+out_remove_host:
+ scsi_remove_host(host);
+ return error;
}
static int
@@ -2750,6 +2838,8 @@ static void megasas_detach_one(struct pc
instance = pci_get_drvdata(pdev);
host = instance->host;
+ sysfs_remove_bin_file(&host->shost_classdev.kobj,
+ &sysfs_max_sectors_attr);
scsi_remove_host(instance->host);
megasas_flush_cache(instance);
megasas_shutdown_controller(instance, MR_DCMD_CTRL_SHUTDOWN);
diff -uprN linux-2.6.22_orig/drivers/scsi/megaraid/megaraid_sas.h linux-2.6.22_new/drivers/scsi/megaraid/megaraid_sas.h
--- linux-2.6.22_orig/drivers/scsi/megaraid/megaraid_sas.h 2007-09-26 13:27:59.000000000 -0700
+++ linux-2.6.22_new/drivers/scsi/megaraid/megaraid_sas.h 2007-09-26 13:27:31.000000000 -0700
@@ -537,6 +537,7 @@ struct megasas_ctrl_info {
#define MEGASAS_DEFAULT_INIT_ID -1
#define MEGASAS_MAX_LUN 8
#define MEGASAS_MAX_LD 64
+#define MEGASAS_DEFAULT_CMD_PER_LUN 128
#define MEGASAS_DBG_LVL 1
@@ -1080,6 +1081,7 @@ struct megasas_instance {
u16 max_num_sge;
u16 max_fw_cmds;
u32 max_sectors_per_req;
+ u32 cmd_per_lun;
struct megasas_cmd **cmd_list;
struct list_head cmd_pool;
On Wed, 26 Sep 2007 11:27:50 -0400 bo yang wrote:
> Adding module parameters to configure max sectors per request & # of cmds per lun.
>
> Signed-off-by: Bo Yang <[email protected]>
>
> ---
> drivers/scsi/megaraid/megaraid_sas.c | 94 ++++++++++++++++++++++++-
> drivers/scsi/megaraid/megaraid_sas.h | 2
> 2 files changed, 94 insertions(+), 2 deletions(-)
>
> diff -uprN linux-2.6.22_orig/drivers/scsi/megaraid/megaraid_sas.c linux-2.6.22_new/drivers/scsi/megaraid/megaraid_sas.c
> --- linux-2.6.22_orig/drivers/scsi/megaraid/megaraid_sas.c 2007-09-26 13:30:36.000000000 -0700
> +++ linux-2.6.22_new/drivers/scsi/megaraid/megaraid_sas.c 2007-09-27 20:37:11.000000000 -0700
> @@ -2301,6 +2318,31 @@ static int megasas_start_aen(struct mega
> class_locale.word);
> }
>
> +static ssize_t
> +sysfs_max_sectors_read(struct kobject *kobj,
> + struct bin_attribute *bin_attr,
> + char *buf, loff_t off, size_t count)
> +{
> + struct Scsi_Host *host = class_to_shost(container_of(kobj,
> + struct class_device, kobj));
> + struct megasas_instance *instance =
> + (struct megasas_instance *)host->hostdata;
> +
> + count = sprintf(buf, "%u\n", instance->max_sectors_per_req);
> +
> + return count+1;
What's the +1 for?
> +}
> +
> +static struct bin_attribute sysfs_max_sectors_attr = {
> + .attr = {
> + .name = "max_sectors",
> + .mode = S_IRUSR|S_IRGRP|S_IROTH,
> + .owner = THIS_MODULE,
> + },
> + .size = 7,
> + .read = sysfs_max_sectors_read,
> +};
> +
> /**
> * megasas_io_attach - Attaches this driver to SCSI mid-layer
> * @instance: Adapter soft state
> @@ -2308,17 +2350,48 @@ static int megasas_start_aen(struct mega
> static int megasas_io_attach(struct megasas_instance *instance)
> {
> struct Scsi_Host *host = instance->host;
> + int error;
>
> /*
> - * Export parameters required by SCSI mid-layer
> + * Export host parameters required by SCSI
> + * mid-layer
> */
> host->irq = instance->pdev->irq;
> host->unique_id = instance->unique_id;
> host->can_queue = instance->max_fw_cmds - MEGASAS_INT_CMDS;
> host->this_id = instance->init_id;
> host->sg_tablesize = instance->max_num_sge;
> +
> + /*
> + * Check if the module parameter value for max_sectors can be used
> + */
> + if (max_sectors && max_sectors <= instance->max_sectors_per_req)
> + instance->max_sectors_per_req = max_sectors;
> + else {
> + if (max_sectors)
> + printk(KERN_INFO
> + "megasas: max_sectors should be > 0 and"
Need a space after "and" above or before "<=" below here.
> + "<= %d\n",
> + instance->max_sectors_per_req);
> + }
> +
> host->max_sectors = instance->max_sectors_per_req;
> - host->cmd_per_lun = 128;
> +
> + /*
> + * Check if the module parameter value for cmd_per_lun can be used
> + */
> + instance->cmd_per_lun = MEGASAS_DEFAULT_CMD_PER_LUN;
> + if (cmd_per_lun && cmd_per_lun <= MEGASAS_DEFAULT_CMD_PER_LUN)
> + instance->cmd_per_lun = cmd_per_lun;
> + else
> + printk(KERN_INFO "megasas: cmd_per_lun should be > 0 and"
Same comment as above.
> + "<= %d\n", MEGASAS_DEFAULT_CMD_PER_LUN);
> +
> + host->cmd_per_lun = instance->cmd_per_lun;
> +
> + printk(KERN_DEBUG "megasas: max_sectors : 0x%x, cmd_per_lun : 0x%x\n",
> + instance->max_sectors_per_req, instance->cmd_per_lun);
> +
> host->max_channel = MEGASAS_MAX_CHANNELS - 1;
> host->max_id = MEGASAS_MAX_DEV_PER_CHANNEL;
> host->max_lun = MEGASAS_MAX_LUN;
---
~Randy
Phaedrus says that Quality is about caring.
bo yang wrote:
> +static ssize_t
> +sysfs_max_sectors_read(struct kobject *kobj,
> + struct bin_attribute *bin_attr,
> + char *buf, loff_t off, size_t count)
> +{
> + struct Scsi_Host *host = class_to_shost(container_of(kobj,
> + struct class_device, kobj));
> + struct megasas_instance *instance =
> + (struct megasas_instance *)host->hostdata;
> +
> + count = sprintf(buf, "%u\n", instance->max_sectors_per_req);
> +
> + return count+1;
> +}
> +
> +static struct bin_attribute sysfs_max_sectors_attr = {
> + .attr = {
> + .name = "max_sectors",
> + .mode = S_IRUSR|S_IRGRP|S_IROTH,
> + .owner = THIS_MODULE,
> + },
> + .size = 7,
> + .read = sysfs_max_sectors_read,
> +};
Why is this implemented as a binary sysfs attribute? Also, can you use
the existing shost_attrs infrastructure that's in the scsi_host_template
like megaraid_mbox uses?
> +
> + /*
> + * Check if the module parameter value for max_sectors can be used
> + */
> + if (max_sectors && max_sectors <= instance->max_sectors_per_req)
> + instance->max_sectors_per_req = max_sectors;
> + else {
> + if (max_sectors)
> + printk(KERN_INFO
> + "megasas: max_sectors should be > 0 and"
> + "<= %d\n",
> + instance->max_sectors_per_req);
> + }
Could be simplified to an else if, which would remove one indent level...
-Brian
--
Brian King
Linux on Power Virtualization
IBM Linux Technology Center
Yang, Bo wrote:
> Brian,
>
> Thanks for your review. What is your objection to the current
> implementation by using bin_attribute?
Binary attributes are generally used for data which cannot
be parsed by the user. Since this attribute is simply a
single decimal value, it makes most sense to just use a regular
class_device_attribute. Additionally, if you use the
existing shost_attrs infrastructure in the scsi_host_template,
you can simplify your code, since you don't need to manually
create and destroy the sysfs files as scsi core will do this for
you.
-Brian
>
> Bo Yang
>
> ------------------------------------------------------------------------
> *From:* Brian King [mailto:[email protected]]
> *Sent:* Fri 9/28/2007 3:30 PM
> *To:* Yang, Bo
> *Cc:* [email protected]; [email protected];
> [email protected]; [email protected]; Patro, Sumant
> *Subject:* Re: [PATCH 3/8] scsi: megaraid_sas - add module param
> max_sectors, cmd_per_lun
>
> bo yang wrote:
>
>> +static ssize_t
>> +sysfs_max_sectors_read(struct kobject *kobj,
>> + struct bin_attribute *bin_attr,
>> + char *buf, loff_t off, size_t count)
>> +{
>> + struct Scsi_Host *host = class_to_shost(container_of(kobj,
>> + struct class_device, kobj));
>> + struct megasas_instance *instance =
>> + (struct megasas_instance *)host->hostdata;
>> +
>> + count = sprintf(buf, "%u\n", instance->max_sectors_per_req);
>> +
>> + return count+1;
>> +}
>> +
>> +static struct bin_attribute sysfs_max_sectors_attr = {
>> + .attr = {
>> + .name = "max_sectors",
>> + .mode = S_IRUSR|S_IRGRP|S_IROTH,
>> + .owner = THIS_MODULE,
>> + },
>> + .size = 7,
>> + .read = sysfs_max_sectors_read,
>> +};
>
> Why is this implemented as a binary sysfs attribute? Also, can you use
> the existing shost_attrs infrastructure that's in the scsi_host_template
> like megaraid_mbox uses?
>
>
>> +
>> + /*
>> + * Check if the module parameter value for max_sectors can be used
>> + */
>> + if (max_sectors && max_sectors <= instance->max_sectors_per_req)
>> + instance->max_sectors_per_req = max_sectors;
>> + else {
>> + if (max_sectors)
>> + printk(KERN_INFO
>> + "megasas: max_sectors should be > 0 and"
>> + "<= %d\n",
>> + instance->max_sectors_per_req);
>> + }
>
> Could be simplified to an else if, which would remove one indent level...
>
> -Brian
>
> --
> Brian King
> Linux on Power Virtualization
> IBM Linux Technology Center
>
--
Brian King
Linux on Power Virtualization
IBM Linux Technology Center