[PATCH 16/17] cxlflash: Add hardware queues attribute
Uma Krishnan
ukrishn at linux.vnet.ibm.com
Thu Apr 13 05:15:53 AEST 2017
From: "Matthew R. Ochs" <mrochs at linux.vnet.ibm.com>
As staging for supporting multiple hardware queues, add an attribute to
show and set the current number of hardware queues for the host. Support
specifying a hard limit or a CPU affinitized value. This will allow the
number of hardware queues to be tuned by a system administrator.
Signed-off-by: Matthew R. Ochs <mrochs at linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn at linux.vnet.ibm.com>
---
drivers/scsi/cxlflash/common.h | 10 ++--
drivers/scsi/cxlflash/main.c | 112 ++++++++++++++++++++++++++++++++++++-----
2 files changed, 106 insertions(+), 16 deletions(-)
diff --git a/drivers/scsi/cxlflash/common.h b/drivers/scsi/cxlflash/common.h
index b5858ae..8fd7a1f 100644
--- a/drivers/scsi/cxlflash/common.h
+++ b/drivers/scsi/cxlflash/common.h
@@ -60,7 +60,9 @@ extern const struct file_operations cxlflash_cxl_fops;
/* SQ for master issued cmds */
#define NUM_SQ_ENTRY CXLFLASH_MAX_CMDS
-#define CXLFLASH_NUM_HWQS 1
+/* Hardware queue definitions */
+#define CXLFLASH_DEF_HWQS 1
+#define CXLFLASH_MAX_HWQS 8
#define PRIMARY_HWQ 0
@@ -201,7 +203,7 @@ struct hwq {
} __aligned(cache_line_size());
struct afu {
- struct hwq hwqs[CXLFLASH_NUM_HWQS];
+ struct hwq hwqs[CXLFLASH_MAX_HWQS];
int (*send_cmd)(struct afu *, struct afu_cmd *);
void (*context_reset)(struct afu_cmd *);
@@ -211,6 +213,8 @@ struct afu {
atomic_t cmds_active; /* Number of currently active AFU commands */
u64 hb;
u32 internal_lun; /* User-desired LUN mode for this AFU */
+ u32 num_hwqs; /* Number of hardware queues */
+ u32 desired_hwqs; /* Desired h/w queues, effective on AFU reset */
char version[16];
u64 interface_version;
@@ -221,7 +225,7 @@ struct afu {
static inline struct hwq *get_hwq(struct afu *afu, u32 index)
{
- WARN_ON(index >= CXLFLASH_NUM_HWQS);
+ WARN_ON(index >= CXLFLASH_MAX_HWQS);
return &afu->hwqs[index];
}
diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c
index 5d06869..113797a 100644
--- a/drivers/scsi/cxlflash/main.c
+++ b/drivers/scsi/cxlflash/main.c
@@ -566,7 +566,7 @@ static void stop_afu(struct cxlflash_cfg *cfg)
ssleep(1);
if (afu_is_irqpoll_enabled(afu)) {
- for (i = 0; i < CXLFLASH_NUM_HWQS; i++) {
+ for (i = 0; i < afu->num_hwqs; i++) {
hwq = get_hwq(afu, i);
irq_poll_disable(&hwq->irqpoll);
@@ -676,13 +676,13 @@ static void term_afu(struct cxlflash_cfg *cfg)
* 2) Unmap the problem state area
* 3) Stop each master context
*/
- for (k = CXLFLASH_NUM_HWQS - 1; k >= 0; k--)
+ for (k = cfg->afu->num_hwqs - 1; k >= 0; k--)
term_intr(cfg, UNMAP_THREE, k);
if (cfg->afu)
stop_afu(cfg);
- for (k = CXLFLASH_NUM_HWQS - 1; k >= 0; k--)
+ for (k = cfg->afu->num_hwqs - 1; k >= 0; k--)
term_mc(cfg, k);
dev_dbg(dev, "%s: returning\n", __func__);
@@ -823,6 +823,7 @@ static int alloc_mem(struct cxlflash_cfg *cfg)
goto out;
}
cfg->afu->parent = cfg;
+ cfg->afu->desired_hwqs = CXLFLASH_DEF_HWQS;
cfg->afu->afu_map = NULL;
out:
return rc;
@@ -1116,7 +1117,7 @@ static void afu_err_intr_init(struct afu *afu)
/* IOARRIN yet), so there is nothing to clear. */
/* set LISN#, it is always sent to the context that wrote IOARRIN */
- for (i = 0; i < CXLFLASH_NUM_HWQS; i++) {
+ for (i = 0; i < afu->num_hwqs; i++) {
hwq = get_hwq(afu, i);
writeq_be(SISL_MSI_SYNC_ERROR, &hwq->host_map->ctx_ctrl);
@@ -1551,7 +1552,7 @@ static void init_pcr(struct cxlflash_cfg *cfg)
}
/* Copy frequently used fields into hwq */
- for (i = 0; i < CXLFLASH_NUM_HWQS; i++) {
+ for (i = 0; i < afu->num_hwqs; i++) {
hwq = get_hwq(afu, i);
hwq->ctx_hndl = (u16) cxl_process_element(hwq->ctx);
@@ -1586,7 +1587,7 @@ static int init_global(struct cxlflash_cfg *cfg)
}
/* Set up RRQ and SQ in HWQ for master issued cmds */
- for (i = 0; i < CXLFLASH_NUM_HWQS; i++) {
+ for (i = 0; i < afu->num_hwqs; i++) {
hwq = get_hwq(afu, i);
hmap = hwq->host_map;
@@ -1640,7 +1641,7 @@ static int init_global(struct cxlflash_cfg *cfg)
/* Set up master's own CTX_CAP to allow real mode, host translation */
/* tables, afu cmds and read/write GSCSI cmds. */
/* First, unlock ctx_cap write by reading mbox */
- for (i = 0; i < CXLFLASH_NUM_HWQS; i++) {
+ for (i = 0; i < afu->num_hwqs; i++) {
hwq = get_hwq(afu, i);
(void)readq_be(&hwq->ctrl_map->mbox_r); /* unlock ctx_cap */
@@ -1670,7 +1671,7 @@ static int start_afu(struct cxlflash_cfg *cfg)
init_pcr(cfg);
/* Initialize each HWQ */
- for (i = 0; i < CXLFLASH_NUM_HWQS; i++) {
+ for (i = 0; i < afu->num_hwqs; i++) {
hwq = get_hwq(afu, i);
/* After an AFU reset, RRQ entries are stale, clear them */
@@ -1888,7 +1889,8 @@ static int init_afu(struct cxlflash_cfg *cfg)
cxl_perst_reloads_same_image(cfg->cxl_afu, true);
- for (i = 0; i < CXLFLASH_NUM_HWQS; i++) {
+ afu->num_hwqs = afu->desired_hwqs;
+ for (i = 0; i < afu->num_hwqs; i++) {
rc = init_mc(cfg, i);
if (rc) {
dev_err(dev, "%s: init_mc failed rc=%d index=%d\n",
@@ -1939,7 +1941,7 @@ static int init_afu(struct cxlflash_cfg *cfg)
}
afu_err_intr_init(cfg->afu);
- for (i = 0; i < CXLFLASH_NUM_HWQS; i++) {
+ for (i = 0; i < afu->num_hwqs; i++) {
hwq = get_hwq(afu, i);
spin_lock_init(&hwq->rrin_slock);
@@ -1953,7 +1955,7 @@ static int init_afu(struct cxlflash_cfg *cfg)
return rc;
err1:
- for (i = CXLFLASH_NUM_HWQS - 1; i >= 0; i--) {
+ for (i = afu->num_hwqs - 1; i >= 0; i--) {
term_intr(cfg, UNMAP_THREE, i);
term_mc(cfg, i);
}
@@ -2550,7 +2552,7 @@ static ssize_t irqpoll_weight_store(struct device *dev,
}
if (afu_is_irqpoll_enabled(afu)) {
- for (i = 0; i < CXLFLASH_NUM_HWQS; i++) {
+ for (i = 0; i < afu->num_hwqs; i++) {
hwq = get_hwq(afu, i);
irq_poll_disable(&hwq->irqpoll);
@@ -2560,7 +2562,7 @@ static ssize_t irqpoll_weight_store(struct device *dev,
afu->irqpoll_weight = weight;
if (weight > 0) {
- for (i = 0; i < CXLFLASH_NUM_HWQS; i++) {
+ for (i = 0; i < afu->num_hwqs; i++) {
hwq = get_hwq(afu, i);
irq_poll_init(&hwq->irqpoll, weight, cxlflash_irqpoll);
@@ -2571,6 +2573,88 @@ static ssize_t irqpoll_weight_store(struct device *dev,
}
/**
+ * num_hwqs_show() - presents the number of hardware queues for the host
+ * @dev: Generic device associated with the host.
+ * @attr: Device attribute representing the number of hardware queues.
+ * @buf: Buffer of length PAGE_SIZE to report back the number of hardware
+ * queues in ASCII.
+ *
+ * Return: The size of the ASCII string returned in @buf.
+ */
+static ssize_t num_hwqs_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct cxlflash_cfg *cfg = shost_priv(class_to_shost(dev));
+ struct afu *afu = cfg->afu;
+
+ return scnprintf(buf, PAGE_SIZE, "%u\n", afu->num_hwqs);
+}
+
+/**
+ * num_hwqs_store() - sets the number of hardware queues for the host
+ * @dev: Generic device associated with the host.
+ * @attr: Device attribute representing the number of hardware queues.
+ * @buf: Buffer of length PAGE_SIZE containing the number of hardware
+ * queues in ASCII.
+ * @count: Length of data resizing in @buf.
+ *
+ * n > 0: num_hwqs = n
+ * n = 0: num_hwqs = num_online_cpus()
+ * n < 0: num_online_cpus() / abs(n)
+ *
+ * Return: The size of the ASCII string returned in @buf.
+ */
+static ssize_t num_hwqs_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct cxlflash_cfg *cfg = shost_priv(class_to_shost(dev));
+ struct afu *afu = cfg->afu;
+ int rc;
+ int nhwqs, num_hwqs;
+
+ rc = kstrtoint(buf, 10, &nhwqs);
+ if (rc)
+ return -EINVAL;
+
+ if (nhwqs >= 1)
+ num_hwqs = nhwqs;
+ else if (nhwqs == 0)
+ num_hwqs = num_online_cpus();
+ else
+ num_hwqs = num_online_cpus() / abs(nhwqs);
+
+ afu->desired_hwqs = min(num_hwqs, CXLFLASH_MAX_HWQS);
+ WARN_ON_ONCE(afu->desired_hwqs == 0);
+
+retry:
+ switch (cfg->state) {
+ case STATE_NORMAL:
+ cfg->state = STATE_RESET;
+ drain_ioctls(cfg);
+ cxlflash_mark_contexts_error(cfg);
+ rc = afu_reset(cfg);
+ if (rc)
+ cfg->state = STATE_FAILTERM;
+ else
+ cfg->state = STATE_NORMAL;
+ wake_up_all(&cfg->reset_waitq);
+ break;
+ case STATE_RESET:
+ wait_event(cfg->reset_waitq, cfg->state != STATE_RESET);
+ if (cfg->state == STATE_NORMAL)
+ goto retry;
+ default:
+ /* Ideally should not happen */
+ dev_err(dev, "%s: Device is not ready, state=%d\n",
+ __func__, cfg->state);
+ break;
+ }
+
+ return count;
+}
+
+/**
* mode_show() - presents the current mode of the device
* @dev: Generic device associated with the device.
* @attr: Device attribute representing the device mode.
@@ -2601,6 +2685,7 @@ static DEVICE_ATTR_RO(port1_lun_table);
static DEVICE_ATTR_RO(port2_lun_table);
static DEVICE_ATTR_RO(port3_lun_table);
static DEVICE_ATTR_RW(irqpoll_weight);
+static DEVICE_ATTR_RW(num_hwqs);
static struct device_attribute *cxlflash_host_attrs[] = {
&dev_attr_port0,
@@ -2614,6 +2699,7 @@ static struct device_attribute *cxlflash_host_attrs[] = {
&dev_attr_port2_lun_table,
&dev_attr_port3_lun_table,
&dev_attr_irqpoll_weight,
+ &dev_attr_num_hwqs,
NULL
};
--
2.1.0
More information about the Linuxppc-dev
mailing list