svcrdma: Deprecate stat variables that are no longer used

Clean up. We are not permitted to remove old proc files. Instead,
convert these variables to stubs that are only ever allowed to
display a value of zero.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

1 files changed, 27 insertions, 57 deletions

diff --git a/net/sunrpc/xprtrdma/svc_rdma.c b/net/sunrpc/xprtrdma/svc_rdma.c
index c8336df7a142..5bc20e9d09cd 100644
--- a/net/sunrpc/xprtrdma/svc_rdma.c
+++ b/net/sunrpc/xprtrdma/svc_rdma.c
@@ -62,53 +62,13 @@ static unsigned int max_max_requests = 16384;
 unsigned int svcrdma_max_req_size = RPCRDMA_DEF_INLINE_THRESH;
 static unsigned int min_max_inline = RPCRDMA_DEF_INLINE_THRESH;
 static unsigned int max_max_inline = RPCRDMA_MAX_INLINE_THRESH;
+static unsigned int svcrdma_stat_unused;
+static unsigned int zero;
 
 struct percpu_counter svcrdma_stat_read;
 struct percpu_counter svcrdma_stat_recv;
 struct percpu_counter svcrdma_stat_sq_starve;
 struct percpu_counter svcrdma_stat_write;
-atomic_t rdma_stat_rq_starve;
-atomic_t rdma_stat_rq_poll;
-atomic_t rdma_stat_rq_prod;
-atomic_t rdma_stat_sq_poll;
-atomic_t rdma_stat_sq_prod;
-
-/*
- * This function implements reading and resetting an atomic_t stat
- * variable through read/write to a proc file. Any write to the file
- * resets the associated statistic to zero. Any read returns it's
- * current value.
- */
-static int read_reset_stat(struct ctl_table *table, int write,
-			   void *buffer, size_t *lenp, loff_t *ppos)
-{
-	atomic_t *stat = (atomic_t *)table->data;
-
-	if (!stat)
-		return -EINVAL;
-
-	if (write)
-		atomic_set(stat, 0);
-	else {
-		char str_buf[32];
-		int len = snprintf(str_buf, 32, "%d\n", atomic_read(stat));
-		if (len >= 32)
-			return -EFAULT;
-		len = strlen(str_buf);
-		if (*ppos > len) {
-			*lenp = 0;
-			return 0;
-		}
-		len -= *ppos;
-		if (len > *lenp)
-			len = *lenp;
-		if (len)
-			memcpy(buffer, str_buf, len);
-		*lenp = len;
-		*ppos += len;
-	}
-	return 0;
-}
 
 enum {
 	SVCRDMA_COUNTER_BUFSIZ	= sizeof(unsigned long long),
@@ -206,38 +166,48 @@ static struct ctl_table svcrdma_parm_table[] = {
 	},
 	{
 		.procname	= "rdma_stat_rq_starve",
-		.data		= &rdma_stat_rq_starve,
-		.maxlen		= sizeof(atomic_t),
+		.data		= &svcrdma_stat_unused,
+		.maxlen		= sizeof(unsigned int),
 		.mode		= 0644,
-		.proc_handler	= read_reset_stat,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &zero,
+		.extra2		= &zero,
 	},
 	{
 		.procname	= "rdma_stat_rq_poll",
-		.data		= &rdma_stat_rq_poll,
-		.maxlen		= sizeof(atomic_t),
+		.data		= &svcrdma_stat_unused,
+		.maxlen		= sizeof(unsigned int),
 		.mode		= 0644,
-		.proc_handler	= read_reset_stat,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &zero,
+		.extra2		= &zero,
 	},
 	{
 		.procname	= "rdma_stat_rq_prod",
-		.data		= &rdma_stat_rq_prod,
-		.maxlen		= sizeof(atomic_t),
+		.data		= &svcrdma_stat_unused,
+		.maxlen		= sizeof(unsigned int),
 		.mode		= 0644,
-		.proc_handler	= read_reset_stat,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &zero,
+		.extra2		= &zero,
 	},
 	{
 		.procname	= "rdma_stat_sq_poll",
-		.data		= &rdma_stat_sq_poll,
-		.maxlen		= sizeof(atomic_t),
+		.data		= &svcrdma_stat_unused,
+		.maxlen		= sizeof(unsigned int),
 		.mode		= 0644,
-		.proc_handler	= read_reset_stat,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &zero,
+		.extra2		= &zero,
 	},
 	{
 		.procname	= "rdma_stat_sq_prod",
-		.data		= &rdma_stat_sq_prod,
-		.maxlen		= sizeof(atomic_t),
+		.data		= &svcrdma_stat_unused,
+		.maxlen		= sizeof(unsigned int),
 		.mode		= 0644,
-		.proc_handler	= read_reset_stat,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &zero,
+		.extra2		= &zero,
 	},
 	{ },
 };