From 7c77c6a9bf9d71711dd3f89858bb0f5157a11919 Mon Sep 17 00:00:00 2001 From: Leon Romanovsky Date: Mon, 18 Feb 2019 22:25:48 +0200 Subject: RDMA/restrack: Prepare restrack_root to addition of extra fields per-type As a preparation to extension of rdma_restrack_root to provide software IDs, which will be per-type too. We convert the rdma_restrack_root from struct with arrays to array of structs. Such conversion allows us to drop rwsem lock in favour of internal XArray lock. Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe --- drivers/infiniband/core/nldev.c | 41 ++++++++++--------------- drivers/infiniband/core/restrack.c | 63 +++++++++++++++----------------------- drivers/infiniband/core/restrack.h | 17 ++-------- 3 files changed, 43 insertions(+), 78 deletions(-) (limited to 'drivers/infiniband/core') diff --git a/drivers/infiniband/core/nldev.c b/drivers/infiniband/core/nldev.c index 54312f9626a1..9b4f891771c4 100644 --- a/drivers/infiniband/core/nldev.c +++ b/drivers/infiniband/core/nldev.c @@ -1018,6 +1018,7 @@ static int res_get_common_dumpit(struct sk_buff *skb, const struct nldev_fill_res_entry *fe = &fill_entries[res_type]; struct nlattr *tb[RDMA_NLDEV_ATTR_MAX]; struct rdma_restrack_entry *res; + struct rdma_restrack_root *rt; int err, ret = 0, idx = 0; struct nlattr *table_attr; struct nlattr *entry_attr; @@ -1028,7 +1029,6 @@ static int res_get_common_dumpit(struct sk_buff *skb, unsigned long id; u32 index, port = 0; bool filled = false; - struct xarray *xa; err = nlmsg_parse(cb->nlh, 0, tb, RDMA_NLDEV_ATTR_MAX - 1, nldev_policy, NULL); @@ -1076,14 +1076,14 @@ static int res_get_common_dumpit(struct sk_buff *skb, has_cap_net_admin = netlink_capable(cb->skb, CAP_NET_ADMIN); - xa = &device->res->xa[res_type]; - down_read(&device->res->rwsem); + rt = &device->res[res_type]; + xa_lock(&rt->xa); /* * FIXME: if the skip ahead is something common this loop should * use xas_for_each & xas_pause to optimize, we can have a lot of * objects. */ - xa_for_each(xa, id, res) { + xa_for_each(&rt->xa, id, res) { if (idx < start) goto next; @@ -1091,45 +1091,37 @@ static int res_get_common_dumpit(struct sk_buff *skb, goto next; if (!rdma_restrack_get(res)) - /* - * Resource is under release now, but we are not - * relesing lock now, so it will be released in - * our next pass, once we will get ->next pointer. - */ goto next; + xa_unlock(&rt->xa); + filled = true; entry_attr = nla_nest_start(skb, fe->entry); if (!entry_attr) { ret = -EMSGSIZE; rdma_restrack_put(res); - up_read(&device->res->rwsem); - break; + goto msg_full; } - up_read(&device->res->rwsem); ret = fe->fill_res_func(skb, has_cap_net_admin, res, port); - down_read(&device->res->rwsem); - /* - * Return resource back, but it won't be released till - * the &device->res.rwsem will be released for write. - */ rdma_restrack_put(res); - if (ret) + if (ret) { nla_nest_cancel(skb, entry_attr); - if (ret == -EMSGSIZE) - break; - if (ret == -EAGAIN) - goto next; - if (ret) + if (ret == -EMSGSIZE) + goto msg_full; + if (ret == -EAGAIN) + goto again; goto res_err; + } nla_nest_end(skb, entry_attr); +again: xa_lock(&rt->xa); next: idx++; } - up_read(&device->res->rwsem); + xa_unlock(&rt->xa); +msg_full: nla_nest_end(skb, table_attr); nlmsg_end(skb, nlh); cb->args[0] = idx; @@ -1146,7 +1138,6 @@ next: idx++; res_err: nla_nest_cancel(skb, table_attr); - up_read(&device->res->rwsem); err: nlmsg_cancel(skb, nlh); diff --git a/drivers/infiniband/core/restrack.c b/drivers/infiniband/core/restrack.c index 6a4b76c66bcb..a5ea3988b4c3 100644 --- a/drivers/infiniband/core/restrack.c +++ b/drivers/infiniband/core/restrack.c @@ -9,7 +9,6 @@ #include #include #include -#include #include "cma_priv.h" #include "restrack.h" @@ -47,15 +46,14 @@ int rdma_restrack_init(struct ib_device *dev) struct rdma_restrack_root *rt; int i; - dev->res = kzalloc(sizeof(*rt), GFP_KERNEL); + dev->res = kcalloc(RDMA_RESTRACK_MAX, sizeof(*rt), GFP_KERNEL); if (!dev->res) return -ENOMEM; rt = dev->res; - for (i = 0 ; i < RDMA_RESTRACK_MAX; i++) - xa_init_flags(&rt->xa[i], XA_FLAGS_ALLOC); - init_rwsem(&rt->rwsem); + for (i = 0; i < RDMA_RESTRACK_MAX; i++) + xa_init_flags(&rt[i].xa, XA_FLAGS_ALLOC); return 0; } @@ -88,7 +86,7 @@ void rdma_restrack_clean(struct ib_device *dev) int i; for (i = 0 ; i < RDMA_RESTRACK_MAX; i++) { - struct xarray *xa = &dev->res->xa[i]; + struct xarray *xa = &dev->res[i].xa; if (!xa_empty(xa)) { unsigned long index; @@ -134,19 +132,19 @@ void rdma_restrack_clean(struct ib_device *dev) int rdma_restrack_count(struct ib_device *dev, enum rdma_restrack_type type, struct pid_namespace *ns) { - struct xarray *xa = &dev->res->xa[type]; + struct rdma_restrack_root *rt = &dev->res[type]; struct rdma_restrack_entry *e; - unsigned long index = 0; + XA_STATE(xas, &rt->xa, 0); u32 cnt = 0; - down_read(&dev->res->rwsem); - xa_for_each(xa, index, e) { + xa_lock(&rt->xa); + xas_for_each(&xas, e, U32_MAX) { if (ns == &init_pid_ns || (!rdma_is_kernel_res(e) && ns == task_active_pid_ns(e->task))) cnt++; } - up_read(&dev->res->rwsem); + xa_unlock(&rt->xa); return cnt; } EXPORT_SYMBOL(rdma_restrack_count); @@ -218,18 +216,16 @@ static void rdma_restrack_add(struct rdma_restrack_entry *res) { struct ib_device *dev = res_to_dev(res); struct rdma_restrack_root *rt; - struct xarray *xa; int ret; if (!dev) return; - rt = dev->res; - xa = &dev->res->xa[res->type]; + rt = &dev->res[res->type]; kref_init(&res->kref); init_completion(&res->comp); - ret = rt_xa_alloc_cyclic(xa, &res->id, res, &rt->next_id[res->type]); + ret = rt_xa_alloc_cyclic(&rt->xa, &res->id, res, &rt->next_id); if (!ret) res->valid = true; } @@ -283,14 +279,14 @@ struct rdma_restrack_entry * rdma_restrack_get_byid(struct ib_device *dev, enum rdma_restrack_type type, u32 id) { - struct xarray *xa = &dev->res->xa[type]; + struct rdma_restrack_root *rt = &dev->res[type]; struct rdma_restrack_entry *res; - down_read(&dev->res->rwsem); - res = xa_load(xa, id); + xa_lock(&rt->xa); + res = xa_load(&rt->xa, id); if (!res || !rdma_restrack_get(res)) res = ERR_PTR(-ENOENT); - up_read(&dev->res->rwsem); + xa_unlock(&rt->xa); return res; } @@ -312,33 +308,22 @@ EXPORT_SYMBOL(rdma_restrack_put); void rdma_restrack_del(struct rdma_restrack_entry *res) { - struct ib_device *dev = res_to_dev(res); - struct xarray *xa; + struct rdma_restrack_entry *old; + struct rdma_restrack_root *rt; + struct ib_device *dev; if (!res->valid) goto out; - /* - * All objects except CM_ID set valid device immediately - * after new object is created, it means that for not valid - * objects will still have "dev". - * - * It is not the case for CM_ID, newly created object has - * this field set to NULL and it is set in _cma_attach_to_dev() - * only. - * - * Because we don't want to add any conditions on call - * to rdma_restrack_del(), the check below protects from - * NULL-dereference. - */ - if (!dev) + dev = res_to_dev(res); + if (WARN_ON(!dev)) return; - xa = &dev->res->xa[res->type]; - down_write(&dev->res->rwsem); - xa_erase(xa, res->id); + rt = &dev->res[res->type]; + + old = xa_erase(&rt->xa, res->id); + WARN_ON(old != res); res->valid = false; - up_write(&dev->res->rwsem); rdma_restrack_put(res); wait_for_completion(&res->comp); diff --git a/drivers/infiniband/core/restrack.h b/drivers/infiniband/core/restrack.h index cf89ef0b8ed5..09a1fbdf578e 100644 --- a/drivers/infiniband/core/restrack.h +++ b/drivers/infiniband/core/restrack.h @@ -7,33 +7,22 @@ #define _RDMA_CORE_RESTRACK_H_ #include -#include /** * struct rdma_restrack_root - main resource tracking management * entity, per-device */ struct rdma_restrack_root { - /* - * @rwsem: Read/write lock to protect erase of entry. - * Lists and insertions are protected by XArray internal lock. - */ - struct rw_semaphore rwsem; /** - * @xa: Array of XArray structures to hold restrack entries. - * We want to use array of XArrays because insertion is type - * dependent. For types with xisiting unique ID (like QPN), - * we will insert to that unique index. For other types, - * we insert based on pointers and auto-allocate unique index. + * @xa: Array of XArray structure to hold restrack entries. */ - struct xarray xa[RDMA_RESTRACK_MAX]; + struct xarray xa; /** * @next_id: Next ID to support cyclic allocation */ - u32 next_id[RDMA_RESTRACK_MAX]; + u32 next_id; }; - int rdma_restrack_init(struct ib_device *dev); void rdma_restrack_clean(struct ib_device *dev); #endif /* _RDMA_CORE_RESTRACK_H_ */ -- cgit v1.2.3-59-g8ed1b