1 files changed, 123 insertions, 75 deletions

diff --git a/net/sunrpc/xprtrdma/svc_rdma.c b/net/sunrpc/xprtrdma/svc_rdma.c
index 526da5d4710b..5bc20e9d09cd 100644
--- a/net/sunrpc/xprtrdma/svc_rdma.c
+++ b/net/sunrpc/xprtrdma/svc_rdma.c
@@ -62,51 +62,47 @@ 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;
 
-atomic_t rdma_stat_recv;
-atomic_t rdma_stat_read;
-atomic_t rdma_stat_write;
-atomic_t rdma_stat_sq_starve;
-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;
+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;
 
-/*
- * 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)
+enum {
+	SVCRDMA_COUNTER_BUFSIZ	= sizeof(unsigned long long),
+};
+
+static int svcrdma_counter_handler(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;
+	struct percpu_counter *stat = (struct percpu_counter *)table->data;
+	char tmp[SVCRDMA_COUNTER_BUFSIZ + 1];
+	int len;
+
+	if (write) {
+		percpu_counter_set(stat, 0);
+		return 0;
 	}
+
+	len = snprintf(tmp, SVCRDMA_COUNTER_BUFSIZ, "%lld\n",
+		       percpu_counter_sum_positive(stat));
+	if (len >= SVCRDMA_COUNTER_BUFSIZ)
+		return -EFAULT;
+	len = strlen(tmp);
+	if (*ppos > len) {
+		*lenp = 0;
+		return 0;
+	}
+	len -= *ppos;
+	if (len > *lenp)
+		len = *lenp;
+	if (len)
+		memcpy(buffer, tmp, len);
+	*lenp = len;
+	*ppos += len;
+
 	return 0;
 }
 
@@ -142,66 +138,76 @@ static struct ctl_table svcrdma_parm_table[] = {
 
 	{
 		.procname	= "rdma_stat_read",
-		.data		= &rdma_stat_read,
-		.maxlen		= sizeof(atomic_t),
+		.data		= &svcrdma_stat_read,
+		.maxlen		= SVCRDMA_COUNTER_BUFSIZ,
 		.mode		= 0644,
-		.proc_handler	= read_reset_stat,
+		.proc_handler	= svcrdma_counter_handler,
 	},
 	{
 		.procname	= "rdma_stat_recv",
-		.data		= &rdma_stat_recv,
-		.maxlen		= sizeof(atomic_t),
+		.data		= &svcrdma_stat_recv,
+		.maxlen		= SVCRDMA_COUNTER_BUFSIZ,
 		.mode		= 0644,
-		.proc_handler	= read_reset_stat,
+		.proc_handler	= svcrdma_counter_handler,
 	},
 	{
 		.procname	= "rdma_stat_write",
-		.data		= &rdma_stat_write,
-		.maxlen		= sizeof(atomic_t),
+		.data		= &svcrdma_stat_write,
+		.maxlen		= SVCRDMA_COUNTER_BUFSIZ,
 		.mode		= 0644,
-		.proc_handler	= read_reset_stat,
+		.proc_handler	= svcrdma_counter_handler,
 	},
 	{
 		.procname	= "rdma_stat_sq_starve",
-		.data		= &rdma_stat_sq_starve,
-		.maxlen		= sizeof(atomic_t),
+		.data		= &svcrdma_stat_sq_starve,
+		.maxlen		= SVCRDMA_COUNTER_BUFSIZ,
 		.mode		= 0644,
-		.proc_handler	= read_reset_stat,
+		.proc_handler	= svcrdma_counter_handler,
 	},
 	{
 		.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,
 	},
 	{ },
 };
@@ -224,27 +230,69 @@ static struct ctl_table svcrdma_root_table[] = {
 	{ },
 };
 
+static void svc_rdma_proc_cleanup(void)
+{
+	if (!svcrdma_table_header)
+		return;
+	unregister_sysctl_table(svcrdma_table_header);
+	svcrdma_table_header = NULL;
+
+	percpu_counter_destroy(&svcrdma_stat_write);
+	percpu_counter_destroy(&svcrdma_stat_sq_starve);
+	percpu_counter_destroy(&svcrdma_stat_recv);
+	percpu_counter_destroy(&svcrdma_stat_read);
+}
+
+static int svc_rdma_proc_init(void)
+{
+	int rc;
+
+	if (svcrdma_table_header)
+		return 0;
+
+	rc = percpu_counter_init(&svcrdma_stat_read, 0, GFP_KERNEL);
+	if (rc)
+		goto out_err;
+	rc = percpu_counter_init(&svcrdma_stat_recv, 0, GFP_KERNEL);
+	if (rc)
+		goto out_err;
+	rc = percpu_counter_init(&svcrdma_stat_sq_starve, 0, GFP_KERNEL);
+	if (rc)
+		goto out_err;
+	rc = percpu_counter_init(&svcrdma_stat_write, 0, GFP_KERNEL);
+	if (rc)
+		goto out_err;
+
+	svcrdma_table_header = register_sysctl_table(svcrdma_root_table);
+	return 0;
+
+out_err:
+	percpu_counter_destroy(&svcrdma_stat_sq_starve);
+	percpu_counter_destroy(&svcrdma_stat_recv);
+	percpu_counter_destroy(&svcrdma_stat_read);
+	return rc;
+}
+
 void svc_rdma_cleanup(void)
 {
 	dprintk("SVCRDMA Module Removed, deregister RPC RDMA transport\n");
-	if (svcrdma_table_header) {
-		unregister_sysctl_table(svcrdma_table_header);
-		svcrdma_table_header = NULL;
-	}
 	svc_unreg_xprt_class(&svc_rdma_class);
+	svc_rdma_proc_cleanup();
 }
 
 int svc_rdma_init(void)
 {
+	int rc;
+
 	dprintk("SVCRDMA Module Init, register RPC RDMA transport\n");
 	dprintk("\tsvcrdma_ord      : %d\n", svcrdma_ord);
 	dprintk("\tmax_requests     : %u\n", svcrdma_max_requests);
 	dprintk("\tmax_bc_requests  : %u\n", svcrdma_max_bc_requests);
 	dprintk("\tmax_inline       : %d\n", svcrdma_max_req_size);
 
-	if (!svcrdma_table_header)
-		svcrdma_table_header =
-			register_sysctl_table(svcrdma_root_table);
+	rc = svc_rdma_proc_init();
+	if (rc)
+		return rc;
 
 	/* Register RDMA with the SVC transport switch */
 	svc_reg_xprt_class(&svc_rdma_class);