1 files changed, 140 insertions, 0 deletions
diff --git a/fs/nfsd/stats.h b/fs/nfsd/stats.h
new file mode 100644
index 000000000..aabfbb1a9
--- /dev/null
+++ b/fs/nfsd/stats.h
@@ -0,0 +1,140 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Statistics for NFS server.
+ *
+ * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
+ */
+#ifndef _NFSD_STATS_H
+#define _NFSD_STATS_H
+
+#include <uapi/linux/nfsd/stats.h>
+#include <linux/percpu_counter.h>
+
+#include "export.h"
+#include "netns.h"
+
+struct proc_dir_entry *nfsd_proc_stat_init(struct net *net);
+void nfsd_proc_stat_shutdown(struct net *net);
+
+/**
+ * nfsd_stats_rc_hits_inc - Count a duplicate reply cache hit
+ * @nn: target network namespace
+ *
+ * These reply cache counters are updated once per RPC. Readers use
+ * percpu_counter_sum_positive(), so local batching does not affect
+ * read accuracy.
+ */
+static inline void nfsd_stats_rc_hits_inc(struct nfsd_net *nn)
+{
+	percpu_counter_add_local(&nn->counter[NFSD_STATS_RC_HITS], 1);
+}
+
+/**
+ * nfsd_stats_rc_misses_inc - Count a duplicate reply cache miss
+ * @nn: target network namespace
+ *
+ * See nfsd_stats_rc_hits_inc() for batching rationale.
+ */
+static inline void nfsd_stats_rc_misses_inc(struct nfsd_net *nn)
+{
+	percpu_counter_add_local(&nn->counter[NFSD_STATS_RC_MISSES], 1);
+}
+
+/**
+ * nfsd_stats_rc_nocache_inc - Count a request not cached in the reply cache
+ * @nn: target network namespace
+ *
+ * See nfsd_stats_rc_hits_inc() for batching rationale.
+ */
+static inline void nfsd_stats_rc_nocache_inc(struct nfsd_net *nn)
+{
+	percpu_counter_add_local(&nn->counter[NFSD_STATS_RC_NOCACHE], 1);
+}
+
+static inline void nfsd_stats_fh_stale_inc(struct nfsd_net *nn,
+					   struct svc_export *exp)
+{
+	percpu_counter_inc(&nn->counter[NFSD_STATS_FH_STALE]);
+	if (exp && exp->ex_stats)
+		percpu_counter_inc(&exp->ex_stats->counter[EXP_STATS_FH_STALE]);
+}
+
+/**
+ * nfsd_stats_io_read_add - Count number of bytes for an NFS READ
+ * @nn: target network namespace
+ * @exp: target export
+ * @amount: byte count
+ *
+ * These counters are updated on every READ request. Readers use
+ * percpu_counter_sum_positive(), so local batching does not affect
+ * read accuracy.
+ */
+static inline void nfsd_stats_io_read_add(struct nfsd_net *nn,
+					  struct svc_export *exp, s64 amount)
+{
+	percpu_counter_add_local(&nn->counter[NFSD_STATS_IO_READ], amount);
+	if (exp && exp->ex_stats)
+		percpu_counter_add_local(&exp->ex_stats->counter[EXP_STATS_IO_READ],
+					 amount);
+}
+
+/**
+ * nfsd_stats_io_write_add - Count number of bytes for an NFS WRITE
+ * @nn: target network namespace
+ * @exp: target export
+ * @amount: byte count
+ *
+ * These counters are updated on every WRITE request. Readers use
+ * percpu_counter_sum_positive(), so local batching does not affect
+ * read accuracy.
+ */
+static inline void nfsd_stats_io_write_add(struct nfsd_net *nn,
+					   struct svc_export *exp, s64 amount)
+{
+	percpu_counter_add_local(&nn->counter[NFSD_STATS_IO_WRITE], amount);
+	if (exp && exp->ex_stats)
+		percpu_counter_add_local(&exp->ex_stats->counter[EXP_STATS_IO_WRITE],
+					 amount);
+}
+
+static inline void nfsd_stats_payload_misses_inc(struct nfsd_net *nn)
+{
+	percpu_counter_inc(&nn->counter[NFSD_STATS_PAYLOAD_MISSES]);
+}
+
+/**
+ * nfsd_stats_drc_mem_usage_add - Add memory used by a cache item
+ * @nn: target network namespace
+ * @amount: byte count
+ *
+ * percpu_counter_add_local() keeps updates on the per-CPU fast
+ * path. The sole reader, percpu_counter_sum_positive(), sums the
+ * per-CPU deltas, so batching locally does not lose accuracy.
+ */
+static inline void nfsd_stats_drc_mem_usage_add(struct nfsd_net *nn, s64 amount)
+{
+	percpu_counter_add_local(&nn->counter[NFSD_STATS_DRC_MEM_USAGE],
+				 amount);
+}
+
+/**
+ * nfsd_stats_drc_mem_usage_sub - Subtract memory used by a cache item
+ * @nn: target network namespace
+ * @amount: byte count
+ *
+ * See nfsd_stats_drc_mem_usage_add() for batching rationale.
+ */
+static inline void nfsd_stats_drc_mem_usage_sub(struct nfsd_net *nn, s64 amount)
+{
+	percpu_counter_sub_local(&nn->counter[NFSD_STATS_DRC_MEM_USAGE],
+				 amount);
+}
+
+#ifdef CONFIG_NFSD_V4
+static inline void nfsd_stats_cb_op_inc(struct nfsd_net *nn, u32 opcode)
+{
+	if (opcode >= OP_CB_GETATTR && opcode <= OP_CB_OFFLOAD)
+		percpu_counter_inc(&nn->cb_counter[opcode]);
+}
+#endif
+#endif /* _NFSD_STATS_H */