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authorDave Jiang <dave.jiang@intel.com>2021-06-04 00:57:35 +0300
committerVinod Koul <vkoul@kernel.org>2021-07-14 09:50:56 +0300
commite753a64bee753136087dfd70b37fdd199e942ea9 (patch)
tree277d9f5bd9500c2ee8d69b417802574b366f4515 /drivers/dma/idxd
parent0dcfe41e9a4ca759ccc87a48e3bb9cc3b08ff1e8 (diff)
downloadlinux-e753a64bee753136087dfd70b37fdd199e942ea9.tar.xz
dmaengine: idxd: Add wq occupancy information to sysfs attribute
Add occupancy information to wq sysfs attribute. Attribute will show wq occupancy data if "WQ Occupancy Support" field in WQCAP is 1. It displays the number of entries currently in this WQ. This is provided as an estimate and should not be relied on to determine whether there is space in the WQ. The data is to provide information to user apps for flow control. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/162275745546.1857062.8765615879420582018.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/dma/idxd')
-rw-r--r--drivers/dma/idxd/registers.h3
-rw-r--r--drivers/dma/idxd/sysfs.c19
2 files changed, 22 insertions, 0 deletions
diff --git a/drivers/dma/idxd/registers.h b/drivers/dma/idxd/registers.h
index c970c3f025f0..7343a8f48819 100644
--- a/drivers/dma/idxd/registers.h
+++ b/drivers/dma/idxd/registers.h
@@ -349,6 +349,9 @@ union wqcfg {
} __packed;
#define WQCFG_PASID_IDX 2
+#define WQCFG_OCCUP_IDX 6
+
+#define WQCFG_OCCUP_MASK 0xffff
/*
* This macro calculates the offset into the WQCFG register
diff --git a/drivers/dma/idxd/sysfs.c b/drivers/dma/idxd/sysfs.c
index 71cd73fefec6..a193de32536d 100644
--- a/drivers/dma/idxd/sysfs.c
+++ b/drivers/dma/idxd/sysfs.c
@@ -1246,6 +1246,24 @@ static ssize_t wq_ats_disable_store(struct device *dev, struct device_attribute
static struct device_attribute dev_attr_wq_ats_disable =
__ATTR(ats_disable, 0644, wq_ats_disable_show, wq_ats_disable_store);
+static ssize_t wq_occupancy_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct idxd_wq *wq = confdev_to_wq(dev);
+ struct idxd_device *idxd = wq->idxd;
+ u32 occup, offset;
+
+ if (!idxd->hw.wq_cap.occupancy)
+ return -EOPNOTSUPP;
+
+ offset = WQCFG_OFFSET(idxd, wq->id, WQCFG_OCCUP_IDX);
+ occup = ioread32(idxd->reg_base + offset) & WQCFG_OCCUP_MASK;
+
+ return sysfs_emit(buf, "%u\n", occup);
+}
+
+static struct device_attribute dev_attr_wq_occupancy =
+ __ATTR(occupancy, 0444, wq_occupancy_show, NULL);
+
static struct attribute *idxd_wq_attributes[] = {
&dev_attr_wq_clients.attr,
&dev_attr_wq_state.attr,
@@ -1261,6 +1279,7 @@ static struct attribute *idxd_wq_attributes[] = {
&dev_attr_wq_max_transfer_size.attr,
&dev_attr_wq_max_batch_size.attr,
&dev_attr_wq_ats_disable.attr,
+ &dev_attr_wq_occupancy.attr,
NULL,
};