| Message ID | 20240825130716.9506-2-mgurtovoy@nvidia.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v1,1/2] virtio_fs: introduce virtio_fs_put_locked helper | expand |
Cc: "Eugenio Pérez" <eperezma@redhat.com> On Sun, Aug 25, 2024 at 04:07:16PM +0300, Max Gurtovoy wrote: > Introduce sysfs entries to provide visibility to the multiple queues > used by the Virtio FS device. This enhancement allows users to query > information about these queues. > > Specifically, add two sysfs entries: > 1. Queue name: Provides the name of each queue (e.g. hiprio/requests.8). > 2. CPU list: Shows the list of CPUs that can process requests for each > queue. > > The CPU list feature is inspired by similar functionality in the block > MQ layer, which provides analogous sysfs entries for block devices. > > These new sysfs entries will improve observability and aid in debugging > and performance tuning of Virtio FS devices. > > Reviewed-by: Idan Zach <izach@nvidia.com> > Reviewed-by: Shai Malin <smalin@nvidia.com> > Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com> > --- > fs/fuse/virtio_fs.c | 147 +++++++++++++++++++++++++++++++++++++++++--- > 1 file changed, 139 insertions(+), 8 deletions(-) > > diff --git a/fs/fuse/virtio_fs.c b/fs/fuse/virtio_fs.c > index 43f7be1d7887..78f579463cca 100644 > --- a/fs/fuse/virtio_fs.c > +++ b/fs/fuse/virtio_fs.c > @@ -56,12 +56,14 @@ struct virtio_fs_vq { > bool connected; > long in_flight; > struct completion in_flight_zero; /* No inflight requests */ > + struct kobject *kobj; > char name[VQ_NAME_LEN]; > } ____cacheline_aligned_in_smp; > > /* A virtio-fs device instance */ > struct virtio_fs { > struct kobject kobj; > + struct kobject *mqs_kobj; > struct list_head list; /* on virtio_fs_instances */ > char *tag; > struct virtio_fs_vq *vqs; > @@ -200,6 +202,74 @@ static const struct kobj_type virtio_fs_ktype = { > .default_groups = virtio_fs_groups, > }; > > +static struct virtio_fs_vq *virtio_fs_kobj_to_vq(struct virtio_fs *fs, > + struct kobject *kobj) > +{ > + int i; > + > + for (i = 0; i < fs->nvqs; i++) { > + if (kobj == fs->vqs[i].kobj) > + return &fs->vqs[i]; > + } > + return NULL; > +} > + > +static ssize_t name_show(struct kobject *kobj, > + struct kobj_attribute *attr, char *buf) > +{ > + struct virtio_fs *fs = container_of(kobj->parent->parent, struct virtio_fs, kobj); > + struct virtio_fs_vq *fsvq = virtio_fs_kobj_to_vq(fs, kobj); > + > + if (!fsvq) > + return -EINVAL; > + return sysfs_emit(buf, "%s\n", fsvq->name); > +} > + > +static struct kobj_attribute virtio_fs_vq_name_attr = __ATTR_RO(name); > + > +static ssize_t cpu_list_show(struct kobject *kobj, > + struct kobj_attribute *attr, char *buf) > +{ > + struct virtio_fs *fs = container_of(kobj->parent->parent, struct virtio_fs, kobj); > + struct virtio_fs_vq *fsvq = virtio_fs_kobj_to_vq(fs, kobj); > + unsigned int cpu, qid; > + const size_t size = PAGE_SIZE - 1; > + bool first = true; > + int ret = 0, pos = 0; > + > + if (!fsvq) > + return -EINVAL; > + > + qid = fsvq->vq->index; > + for (cpu = 0; cpu < nr_cpu_ids; cpu++) { > + if (qid < VQ_REQUEST || (fs->mq_map[cpu] == qid - VQ_REQUEST)) { > + if (first) > + ret = snprintf(buf + pos, size - pos, "%u", cpu); > + else > + ret = snprintf(buf + pos, size - pos, ", %u", cpu); > + > + if (ret >= size - pos) > + break; > + first = false; > + pos += ret; > + } > + } > + ret = snprintf(buf + pos, size + 1 - pos, "\n"); > + return pos + ret; > +} > + > +static struct kobj_attribute virtio_fs_vq_cpu_list_attr = __ATTR_RO(cpu_list); > + > +static struct attribute *virtio_fs_vq_attrs[] = { > + &virtio_fs_vq_name_attr.attr, > + &virtio_fs_vq_cpu_list_attr.attr, > + NULL > +}; > + > +static struct attribute_group virtio_fs_vq_attr_group = { > + .attrs = virtio_fs_vq_attrs, > +}; > + > /* Make sure virtiofs_mutex is held */ > static void virtio_fs_put_locked(struct virtio_fs *fs) > { > @@ -280,6 +350,50 @@ static void virtio_fs_start_all_queues(struct virtio_fs *fs) > } > } > > +static void virtio_fs_delete_queues_sysfs(struct virtio_fs *fs) > +{ > + struct virtio_fs_vq *fsvq; > + int i; > + > + for (i = 0; i < fs->nvqs; i++) { > + fsvq = &fs->vqs[i]; > + kobject_put(fsvq->kobj); > + } > +} > + > +static int virtio_fs_add_queues_sysfs(struct virtio_fs *fs) > +{ > + struct virtio_fs_vq *fsvq; > + char buff[12]; > + int i, j, ret; > + > + for (i = 0; i < fs->nvqs; i++) { > + fsvq = &fs->vqs[i]; > + > + sprintf(buff, "%d", i); > + fsvq->kobj = kobject_create_and_add(buff, fs->mqs_kobj); > + if (!fs->mqs_kobj) { > + ret = -ENOMEM; > + goto out_del; > + } > + > + ret = sysfs_create_group(fsvq->kobj, &virtio_fs_vq_attr_group); > + if (ret) { > + kobject_put(fsvq->kobj); > + goto out_del; > + } > + } > + > + return 0; > + > +out_del: > + for (j = 0; j < i; j++) { > + fsvq = &fs->vqs[j]; > + kobject_put(fsvq->kobj); > + } > + return ret; > +} > + > /* Add a new instance to the list or return -EEXIST if tag name exists*/ > static int virtio_fs_add_instance(struct virtio_device *vdev, > struct virtio_fs *fs) > @@ -303,17 +417,22 @@ static int virtio_fs_add_instance(struct virtio_device *vdev, > */ > fs->kobj.kset = virtio_fs_kset; > ret = kobject_add(&fs->kobj, NULL, "%d", vdev->index); > - if (ret < 0) { > - mutex_unlock(&virtio_fs_mutex); > - return ret; > + if (ret < 0) > + goto out_unlock; > + > + fs->mqs_kobj = kobject_create_and_add("mqs", &fs->kobj); > + if (!fs->mqs_kobj) { > + ret = -ENOMEM; > + goto out_del; > } > > ret = sysfs_create_link(&fs->kobj, &vdev->dev.kobj, "device"); > - if (ret < 0) { > - kobject_del(&fs->kobj); > - mutex_unlock(&virtio_fs_mutex); > - return ret; > - } > + if (ret < 0) > + goto out_put; > + > + ret = virtio_fs_add_queues_sysfs(fs); > + if (ret) > + goto out_remove; > > list_add_tail(&fs->list, &virtio_fs_instances); > > @@ -322,6 +441,16 @@ static int virtio_fs_add_instance(struct virtio_device *vdev, > kobject_uevent(&fs->kobj, KOBJ_ADD); > > return 0; > + > +out_remove: > + sysfs_remove_link(&fs->kobj, "device"); > +out_put: > + kobject_put(fs->mqs_kobj); > +out_del: > + kobject_del(&fs->kobj); > +out_unlock: > + mutex_unlock(&virtio_fs_mutex); > + return ret; > } > > /* Return the virtio_fs with a given tag, or NULL */ > @@ -1050,7 +1179,9 @@ static void virtio_fs_remove(struct virtio_device *vdev) > mutex_lock(&virtio_fs_mutex); > /* This device is going away. No one should get new reference */ > list_del_init(&fs->list); > + virtio_fs_delete_queues_sysfs(fs); > sysfs_remove_link(&fs->kobj, "device"); > + kobject_put(fs->mqs_kobj); > kobject_del(&fs->kobj); > virtio_fs_stop_all_queues(fs); > virtio_fs_drain_all_queues_locked(fs); > -- > 2.18.1
diff --git a/fs/fuse/virtio_fs.c b/fs/fuse/virtio_fs.c index 43f7be1d7887..78f579463cca 100644 --- a/fs/fuse/virtio_fs.c +++ b/fs/fuse/virtio_fs.c @@ -56,12 +56,14 @@ struct virtio_fs_vq { bool connected; long in_flight; struct completion in_flight_zero; /* No inflight requests */ + struct kobject *kobj; char name[VQ_NAME_LEN]; } ____cacheline_aligned_in_smp; /* A virtio-fs device instance */ struct virtio_fs { struct kobject kobj; + struct kobject *mqs_kobj; struct list_head list; /* on virtio_fs_instances */ char *tag; struct virtio_fs_vq *vqs; @@ -200,6 +202,74 @@ static const struct kobj_type virtio_fs_ktype = { .default_groups = virtio_fs_groups, }; +static struct virtio_fs_vq *virtio_fs_kobj_to_vq(struct virtio_fs *fs, + struct kobject *kobj) +{ + int i; + + for (i = 0; i < fs->nvqs; i++) { + if (kobj == fs->vqs[i].kobj) + return &fs->vqs[i]; + } + return NULL; +} + +static ssize_t name_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct virtio_fs *fs = container_of(kobj->parent->parent, struct virtio_fs, kobj); + struct virtio_fs_vq *fsvq = virtio_fs_kobj_to_vq(fs, kobj); + + if (!fsvq) + return -EINVAL; + return sysfs_emit(buf, "%s\n", fsvq->name); +} + +static struct kobj_attribute virtio_fs_vq_name_attr = __ATTR_RO(name); + +static ssize_t cpu_list_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct virtio_fs *fs = container_of(kobj->parent->parent, struct virtio_fs, kobj); + struct virtio_fs_vq *fsvq = virtio_fs_kobj_to_vq(fs, kobj); + unsigned int cpu, qid; + const size_t size = PAGE_SIZE - 1; + bool first = true; + int ret = 0, pos = 0; + + if (!fsvq) + return -EINVAL; + + qid = fsvq->vq->index; + for (cpu = 0; cpu < nr_cpu_ids; cpu++) { + if (qid < VQ_REQUEST || (fs->mq_map[cpu] == qid - VQ_REQUEST)) { + if (first) + ret = snprintf(buf + pos, size - pos, "%u", cpu); + else + ret = snprintf(buf + pos, size - pos, ", %u", cpu); + + if (ret >= size - pos) + break; + first = false; + pos += ret; + } + } + ret = snprintf(buf + pos, size + 1 - pos, "\n"); + return pos + ret; +} + +static struct kobj_attribute virtio_fs_vq_cpu_list_attr = __ATTR_RO(cpu_list); + +static struct attribute *virtio_fs_vq_attrs[] = { + &virtio_fs_vq_name_attr.attr, + &virtio_fs_vq_cpu_list_attr.attr, + NULL +}; + +static struct attribute_group virtio_fs_vq_attr_group = { + .attrs = virtio_fs_vq_attrs, +}; + /* Make sure virtiofs_mutex is held */ static void virtio_fs_put_locked(struct virtio_fs *fs) { @@ -280,6 +350,50 @@ static void virtio_fs_start_all_queues(struct virtio_fs *fs) } } +static void virtio_fs_delete_queues_sysfs(struct virtio_fs *fs) +{ + struct virtio_fs_vq *fsvq; + int i; + + for (i = 0; i < fs->nvqs; i++) { + fsvq = &fs->vqs[i]; + kobject_put(fsvq->kobj); + } +} + +static int virtio_fs_add_queues_sysfs(struct virtio_fs *fs) +{ + struct virtio_fs_vq *fsvq; + char buff[12]; + int i, j, ret; + + for (i = 0; i < fs->nvqs; i++) { + fsvq = &fs->vqs[i]; + + sprintf(buff, "%d", i); + fsvq->kobj = kobject_create_and_add(buff, fs->mqs_kobj); + if (!fs->mqs_kobj) { + ret = -ENOMEM; + goto out_del; + } + + ret = sysfs_create_group(fsvq->kobj, &virtio_fs_vq_attr_group); + if (ret) { + kobject_put(fsvq->kobj); + goto out_del; + } + } + + return 0; + +out_del: + for (j = 0; j < i; j++) { + fsvq = &fs->vqs[j]; + kobject_put(fsvq->kobj); + } + return ret; +} + /* Add a new instance to the list or return -EEXIST if tag name exists*/ static int virtio_fs_add_instance(struct virtio_device *vdev, struct virtio_fs *fs) @@ -303,17 +417,22 @@ static int virtio_fs_add_instance(struct virtio_device *vdev, */ fs->kobj.kset = virtio_fs_kset; ret = kobject_add(&fs->kobj, NULL, "%d", vdev->index); - if (ret < 0) { - mutex_unlock(&virtio_fs_mutex); - return ret; + if (ret < 0) + goto out_unlock; + + fs->mqs_kobj = kobject_create_and_add("mqs", &fs->kobj); + if (!fs->mqs_kobj) { + ret = -ENOMEM; + goto out_del; } ret = sysfs_create_link(&fs->kobj, &vdev->dev.kobj, "device"); - if (ret < 0) { - kobject_del(&fs->kobj); - mutex_unlock(&virtio_fs_mutex); - return ret; - } + if (ret < 0) + goto out_put; + + ret = virtio_fs_add_queues_sysfs(fs); + if (ret) + goto out_remove; list_add_tail(&fs->list, &virtio_fs_instances); @@ -322,6 +441,16 @@ static int virtio_fs_add_instance(struct virtio_device *vdev, kobject_uevent(&fs->kobj, KOBJ_ADD); return 0; + +out_remove: + sysfs_remove_link(&fs->kobj, "device"); +out_put: + kobject_put(fs->mqs_kobj); +out_del: + kobject_del(&fs->kobj); +out_unlock: + mutex_unlock(&virtio_fs_mutex); + return ret; } /* Return the virtio_fs with a given tag, or NULL */ @@ -1050,7 +1179,9 @@ static void virtio_fs_remove(struct virtio_device *vdev) mutex_lock(&virtio_fs_mutex); /* This device is going away. No one should get new reference */ list_del_init(&fs->list); + virtio_fs_delete_queues_sysfs(fs); sysfs_remove_link(&fs->kobj, "device"); + kobject_put(fs->mqs_kobj); kobject_del(&fs->kobj); virtio_fs_stop_all_queues(fs); virtio_fs_drain_all_queues_locked(fs);