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| author | Trond Myklebust <trond.myklebust@primarydata.com> | 2017-04-28 10:52:42 -0400 |
|---|---|---|
| committer | Trond Myklebust <trond.myklebust@hammerspace.com> | 2019-07-06 14:54:49 -0400 |
| commit | 21f0ffaff510b0530bfdf77da7133c0b99dee2fe (patch) | |
| tree | 0302c053444f3a371d7c188a33f9834fb7cbc31e /net/sunrpc/clnt.c | |
| parent | 44942b4e457beda00981f616402a1a791e8c616e (diff) | |
| download | lwn-21f0ffaff510b0530bfdf77da7133c0b99dee2fe.tar.gz lwn-21f0ffaff510b0530bfdf77da7133c0b99dee2fe.zip | |
SUNRPC: Add basic load balancing to the transport switch
For now, just count the queue length. It is less accurate than counting
number of bytes queued, but easier to implement.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Diffstat (limited to 'net/sunrpc/clnt.c')
| -rw-r--r-- | net/sunrpc/clnt.c | 40 |
1 files changed, 37 insertions, 3 deletions
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c index b03bfa055c08..976eab68bb5d 100644 --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -968,13 +968,47 @@ out: } EXPORT_SYMBOL_GPL(rpc_bind_new_program); +static struct rpc_xprt * +rpc_task_get_xprt(struct rpc_clnt *clnt) +{ + struct rpc_xprt_switch *xps; + struct rpc_xprt *xprt= xprt_iter_get_next(&clnt->cl_xpi); + + if (!xprt) + return NULL; + rcu_read_lock(); + xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); + atomic_long_inc(&xps->xps_queuelen); + rcu_read_unlock(); + atomic_long_inc(&xprt->queuelen); + + return xprt; +} + +static void +rpc_task_release_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt) +{ + struct rpc_xprt_switch *xps; + + atomic_long_dec(&xprt->queuelen); + rcu_read_lock(); + xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); + atomic_long_dec(&xps->xps_queuelen); + rcu_read_unlock(); + + xprt_put(xprt); +} + void rpc_task_release_transport(struct rpc_task *task) { struct rpc_xprt *xprt = task->tk_xprt; if (xprt) { task->tk_xprt = NULL; - xprt_put(xprt); + if (task->tk_client) + rpc_task_release_xprt(task->tk_client, xprt); + else + xprt_put(xprt); } } EXPORT_SYMBOL_GPL(rpc_task_release_transport); @@ -983,6 +1017,7 @@ void rpc_task_release_client(struct rpc_task *task) { struct rpc_clnt *clnt = task->tk_client; + rpc_task_release_transport(task); if (clnt != NULL) { /* Remove from client task list */ spin_lock(&clnt->cl_lock); @@ -992,14 +1027,13 @@ void rpc_task_release_client(struct rpc_task *task) rpc_release_client(clnt); } - rpc_task_release_transport(task); } static void rpc_task_set_transport(struct rpc_task *task, struct rpc_clnt *clnt) { if (!task->tk_xprt) - task->tk_xprt = xprt_iter_get_next(&clnt->cl_xpi); + task->tk_xprt = rpc_task_get_xprt(clnt); } static |