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| author | Xie Yongji <xieyongji@bytedance.com> | 2023-03-23 06:30:43 +0100 |
|---|---|---|
| committer | Michael S. Tsirkin <mst@redhat.com> | 2023-04-21 09:02:32 +0200 |
| commit | b774f93d87e198481680873b22c2a443e10c3f93 (patch) | |
| tree | 1f31b126eecb92c1cb4efacb7f6e38dd5992bb58 /drivers/vdpa | |
| parent | vduse: Delay iova domain creation (diff) | |
| download | linux-b774f93d87e198481680873b22c2a443e10c3f93.tar.xz linux-b774f93d87e198481680873b22c2a443e10c3f93.zip | |
vduse: Support specifying bounce buffer size via sysfs
As discussed in [1], this adds sysfs interface to support
specifying bounce buffer size in virtio-vdpa case. It would
be a performance tuning parameter for high throughput workloads.
[1] https://lore.kernel.org/netdev/e8f25a35-9d45-69f9-795d-bdbbb90337a3@redhat.com/
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20230323053043.35-12-xieyongji@bytedance.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'drivers/vdpa')
| -rw-r--r-- | drivers/vdpa/vdpa_user/vduse_dev.c | 45 |
1 files changed, 44 insertions, 1 deletions
diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c index ccca84d51a28..34eebdf030af 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -37,8 +37,11 @@ #define DRV_LICENSE "GPL v2" #define VDUSE_DEV_MAX (1U << MINORBITS) +#define VDUSE_MAX_BOUNCE_SIZE (1024 * 1024 * 1024) +#define VDUSE_MIN_BOUNCE_SIZE (1024 * 1024) #define VDUSE_BOUNCE_SIZE (64 * 1024 * 1024) -#define VDUSE_IOVA_SIZE (128 * 1024 * 1024) +/* 128 MB reserved for virtqueue creation */ +#define VDUSE_IOVA_SIZE (VDUSE_MAX_BOUNCE_SIZE + 128 * 1024 * 1024) #define VDUSE_MSG_DEFAULT_TIMEOUT 30 #define IRQ_UNBOUND -1 @@ -1715,8 +1718,48 @@ static ssize_t msg_timeout_store(struct device *device, static DEVICE_ATTR_RW(msg_timeout); +static ssize_t bounce_size_show(struct device *device, + struct device_attribute *attr, char *buf) +{ + struct vduse_dev *dev = dev_get_drvdata(device); + + return sysfs_emit(buf, "%u\n", dev->bounce_size); +} + +static ssize_t bounce_size_store(struct device *device, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct vduse_dev *dev = dev_get_drvdata(device); + unsigned int bounce_size; + int ret; + + ret = -EPERM; + mutex_lock(&dev->domain_lock); + if (dev->domain) + goto unlock; + + ret = kstrtouint(buf, 10, &bounce_size); + if (ret < 0) + goto unlock; + + ret = -EINVAL; + if (bounce_size > VDUSE_MAX_BOUNCE_SIZE || + bounce_size < VDUSE_MIN_BOUNCE_SIZE) + goto unlock; + + dev->bounce_size = bounce_size & PAGE_MASK; + ret = count; +unlock: + mutex_unlock(&dev->domain_lock); + return ret; +} + +static DEVICE_ATTR_RW(bounce_size); + static struct attribute *vduse_dev_attrs[] = { &dev_attr_msg_timeout.attr, + &dev_attr_bounce_size.attr, NULL }; |