diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-07-19 00:32:33 +0300 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-07-19 00:32:33 +0300 |
commit | 6860c981b9672324cb53b883cfda8d2ea1445ff1 (patch) | |
tree | d97a47712479bc2f886012d7f2da8b00ac504f3a /net/sunrpc/xprtmultipath.c | |
parent | 0570bc8b7c9b41deba6f61ac218922e7168ad648 (diff) | |
parent | d5b9216fd5114be4ed98ca9c1ecc5f164cd8cf5e (diff) | |
download | linux-6860c981b9672324cb53b883cfda8d2ea1445ff1.tar.xz |
Merge tag 'nfs-for-5.3-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
Stable fixes:
- SUNRPC: Ensure bvecs are re-synced when we re-encode the RPC
request
- Fix an Oops in ff_layout_track_ds_error due to a PTR_ERR()
dereference
- Revert buggy NFS readdirplus optimisation
- NFSv4: Handle the special Linux file open access mode
- pnfs: Fix a problem where we gratuitously start doing I/O through
the MDS
Features:
- Allow NFS client to set up multiple TCP connections to the server
using a new 'nconnect=X' mount option. Queue length is used to
balance load.
- Enhance statistics reporting to report on all transports when using
multiple connections.
- Speed up SUNRPC by removing bh-safe spinlocks
- Add a mechanism to allow NFSv4 to request that containers set a
unique per-host identifier for when the hostname is not set.
- Ensure NFSv4 updates the lease_time after a clientid update
Bugfixes and cleanup:
- Fix use-after-free in rpcrdma_post_recvs
- Fix a memory leak when nfs_match_client() is interrupted
- Fix buggy file access checking in NFSv4 open for execute
- disable unsupported client side deduplication
- Fix spurious client disconnections
- Fix occasional RDMA transport deadlock
- Various RDMA cleanups
- Various tracepoint fixes
- Fix the TCP callback channel to guarantee the server can actually
send the number of callback requests that was negotiated at mount
time"
* tag 'nfs-for-5.3-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (68 commits)
pnfs/flexfiles: Add tracepoints for detecting pnfs fallback to MDS
pnfs: Fix a problem where we gratuitously start doing I/O through the MDS
SUNRPC: Optimise transport balancing code
SUNRPC: Ensure the bvecs are reset when we re-encode the RPC request
pnfs/flexfiles: Fix PTR_ERR() dereferences in ff_layout_track_ds_error
NFSv4: Don't use the zero stateid with layoutget
SUNRPC: Fix up backchannel slot table accounting
SUNRPC: Fix initialisation of struct rpc_xprt_switch
SUNRPC: Skip zero-refcount transports
SUNRPC: Replace division by multiplication in calculation of queue length
NFSv4: Validate the stateid before applying it to state recovery
nfs4.0: Refetch lease_time after clientid update
nfs4: Rename nfs41_setup_state_renewal
nfs4: Make nfs4_proc_get_lease_time available for nfs4.0
nfs: Fix copy-and-paste error in debug message
NFS: Replace 16 seq_printf() calls by seq_puts()
NFS: Use seq_putc() in nfs_show_stats()
Revert "NFS: readdirplus optimization by cache mechanism" (memleak)
SUNRPC: Fix transport accounting when caller specifies an rpc_xprt
NFS: Record task, client ID, and XID in xdr_status trace points
...
Diffstat (limited to 'net/sunrpc/xprtmultipath.c')
-rw-r--r-- | net/sunrpc/xprtmultipath.c | 89 |
1 files changed, 67 insertions, 22 deletions
diff --git a/net/sunrpc/xprtmultipath.c b/net/sunrpc/xprtmultipath.c index 8394124126f8..78c075a68c04 100644 --- a/net/sunrpc/xprtmultipath.c +++ b/net/sunrpc/xprtmultipath.c @@ -19,7 +19,7 @@ #include <linux/sunrpc/addr.h> #include <linux/sunrpc/xprtmultipath.h> -typedef struct rpc_xprt *(*xprt_switch_find_xprt_t)(struct list_head *head, +typedef struct rpc_xprt *(*xprt_switch_find_xprt_t)(struct rpc_xprt_switch *xps, const struct rpc_xprt *cur); static const struct rpc_xprt_iter_ops rpc_xprt_iter_singular; @@ -36,6 +36,7 @@ static void xprt_switch_add_xprt_locked(struct rpc_xprt_switch *xps, if (xps->xps_nxprts == 0) xps->xps_net = xprt->xprt_net; xps->xps_nxprts++; + xps->xps_nactive++; } /** @@ -51,8 +52,7 @@ void rpc_xprt_switch_add_xprt(struct rpc_xprt_switch *xps, if (xprt == NULL) return; spin_lock(&xps->xps_lock); - if ((xps->xps_net == xprt->xprt_net || xps->xps_net == NULL) && - !rpc_xprt_switch_has_addr(xps, (struct sockaddr *)&xprt->addr)) + if (xps->xps_net == xprt->xprt_net || xps->xps_net == NULL) xprt_switch_add_xprt_locked(xps, xprt); spin_unlock(&xps->xps_lock); } @@ -62,6 +62,7 @@ static void xprt_switch_remove_xprt_locked(struct rpc_xprt_switch *xps, { if (unlikely(xprt == NULL)) return; + xps->xps_nactive--; xps->xps_nxprts--; if (xps->xps_nxprts == 0) xps->xps_net = NULL; @@ -102,7 +103,9 @@ struct rpc_xprt_switch *xprt_switch_alloc(struct rpc_xprt *xprt, if (xps != NULL) { spin_lock_init(&xps->xps_lock); kref_init(&xps->xps_kref); - xps->xps_nxprts = 0; + xps->xps_nxprts = xps->xps_nactive = 0; + atomic_long_set(&xps->xps_queuelen, 0); + xps->xps_net = NULL; INIT_LIST_HEAD(&xps->xps_xprt_list); xps->xps_iter_ops = &rpc_xprt_iter_singular; xprt_switch_add_xprt_locked(xps, xprt); @@ -193,9 +196,21 @@ void xprt_iter_default_rewind(struct rpc_xprt_iter *xpi) } static +bool xprt_is_active(const struct rpc_xprt *xprt) +{ + return kref_read(&xprt->kref) != 0; +} + +static struct rpc_xprt *xprt_switch_find_first_entry(struct list_head *head) { - return list_first_or_null_rcu(head, struct rpc_xprt, xprt_switch); + struct rpc_xprt *pos; + + list_for_each_entry_rcu(pos, head, xprt_switch) { + if (xprt_is_active(pos)) + return pos; + } + return NULL; } static @@ -213,9 +228,12 @@ struct rpc_xprt *xprt_switch_find_current_entry(struct list_head *head, const struct rpc_xprt *cur) { struct rpc_xprt *pos; + bool found = false; list_for_each_entry_rcu(pos, head, xprt_switch) { if (cur == pos) + found = true; + if (found && xprt_is_active(pos)) return pos; } return NULL; @@ -260,9 +278,12 @@ struct rpc_xprt *xprt_switch_find_next_entry(struct list_head *head, const struct rpc_xprt *cur) { struct rpc_xprt *pos, *prev = NULL; + bool found = false; list_for_each_entry_rcu(pos, head, xprt_switch) { if (cur == prev) + found = true; + if (found && xprt_is_active(pos)) return pos; prev = pos; } @@ -270,22 +291,15 @@ struct rpc_xprt *xprt_switch_find_next_entry(struct list_head *head, } static -struct rpc_xprt *xprt_switch_set_next_cursor(struct list_head *head, +struct rpc_xprt *xprt_switch_set_next_cursor(struct rpc_xprt_switch *xps, struct rpc_xprt **cursor, xprt_switch_find_xprt_t find_next) { - struct rpc_xprt *cur, *pos, *old; + struct rpc_xprt *pos, *old; - cur = READ_ONCE(*cursor); - for (;;) { - old = cur; - pos = find_next(head, old); - if (pos == NULL) - break; - cur = cmpxchg_relaxed(cursor, old, pos); - if (cur == old) - break; - } + old = smp_load_acquire(cursor); + pos = find_next(xps, old); + smp_store_release(cursor, pos); return pos; } @@ -297,13 +311,11 @@ struct rpc_xprt *xprt_iter_next_entry_multiple(struct rpc_xprt_iter *xpi, if (xps == NULL) return NULL; - return xprt_switch_set_next_cursor(&xps->xps_xprt_list, - &xpi->xpi_cursor, - find_next); + return xprt_switch_set_next_cursor(xps, &xpi->xpi_cursor, find_next); } static -struct rpc_xprt *xprt_switch_find_next_entry_roundrobin(struct list_head *head, +struct rpc_xprt *__xprt_switch_find_next_entry_roundrobin(struct list_head *head, const struct rpc_xprt *cur) { struct rpc_xprt *ret; @@ -315,6 +327,31 @@ struct rpc_xprt *xprt_switch_find_next_entry_roundrobin(struct list_head *head, } static +struct rpc_xprt *xprt_switch_find_next_entry_roundrobin(struct rpc_xprt_switch *xps, + const struct rpc_xprt *cur) +{ + struct list_head *head = &xps->xps_xprt_list; + struct rpc_xprt *xprt; + unsigned int nactive; + + for (;;) { + unsigned long xprt_queuelen, xps_queuelen; + + xprt = __xprt_switch_find_next_entry_roundrobin(head, cur); + if (!xprt) + break; + xprt_queuelen = atomic_long_read(&xprt->queuelen); + xps_queuelen = atomic_long_read(&xps->xps_queuelen); + nactive = READ_ONCE(xps->xps_nactive); + /* Exit loop if xprt_queuelen <= average queue length */ + if (xprt_queuelen * nactive <= xps_queuelen) + break; + cur = xprt; + } + return xprt; +} + +static struct rpc_xprt *xprt_iter_next_entry_roundrobin(struct rpc_xprt_iter *xpi) { return xprt_iter_next_entry_multiple(xpi, @@ -322,9 +359,17 @@ struct rpc_xprt *xprt_iter_next_entry_roundrobin(struct rpc_xprt_iter *xpi) } static +struct rpc_xprt *xprt_switch_find_next_entry_all(struct rpc_xprt_switch *xps, + const struct rpc_xprt *cur) +{ + return xprt_switch_find_next_entry(&xps->xps_xprt_list, cur); +} + +static struct rpc_xprt *xprt_iter_next_entry_all(struct rpc_xprt_iter *xpi) { - return xprt_iter_next_entry_multiple(xpi, xprt_switch_find_next_entry); + return xprt_iter_next_entry_multiple(xpi, + xprt_switch_find_next_entry_all); } /* |