svn commit: r277583 - stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs

[Xin LI]

Author: delphij
Date: Fri Jan 23 18:23:19 2015
New Revision: 277583
URL: https://svnweb.freebsd.org/changeset/base/277583

Log:
  MFC r275748: MFV r247174:
  
  Expose arc_meta_limit, et al via kstats.
  
  Note that as a result, vfs.zfs.arc_meta_used is removed.
  The existing vfs.zfs.arc_meta_limit sysctl/tunable is retained
  with a SYSCTL_PROC wrapper.
  
  Illumos ZFS issues:
      3561 arc_meta_limit should be exposed via kstats
  
  Relnotes:	yes

Modified:
  stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c
Directory Properties:
  stable/10/   (props changed)

Modified: stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c
==============================================================================
--- stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c	Fri Jan 23 18:16:36 2015	(r277582)
+++ stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c	Fri Jan 23 18:23:19 2015	(r277583)
@@ -205,6 +205,7 @@ uint64_t zfs_arc_average_blocksize = 8 *
 u_int zfs_arc_free_target = 0;
 
 static int sysctl_vfs_zfs_arc_free_target(SYSCTL_HANDLER_ARGS);
+static int sysctl_vfs_zfs_arc_meta_limit(SYSCTL_HANDLER_ARGS);
 
 #ifdef _KERNEL
 static void
@@ -262,6 +263,15 @@ sysctl_vfs_zfs_arc_free_target(SYSCTL_HA
 
 	return (0);
 }
+
+/*
+ * Must be declared here, before the definition of corresponding kstat
+ * macro which uses the same names will confuse the compiler.
+ */
+SYSCTL_PROC(_vfs_zfs, OID_AUTO, arc_meta_limit,
+    CTLTYPE_U64 | CTLFLAG_MPSAFE | CTLFLAG_RW, 0, sizeof(uint64_t),
+    sysctl_vfs_zfs_arc_meta_limit, "QU",
+    "ARC metadata limit");
 #endif
 
 /*
@@ -416,6 +426,9 @@ typedef struct arc_stats {
 	kstat_named_t arcstat_duplicate_buffers;
 	kstat_named_t arcstat_duplicate_buffers_size;
 	kstat_named_t arcstat_duplicate_reads;
+	kstat_named_t arcstat_meta_used;
+	kstat_named_t arcstat_meta_limit;
+	kstat_named_t arcstat_meta_max;
 } arc_stats_t;
 
 static arc_stats_t arc_stats = {
@@ -493,7 +506,10 @@ static arc_stats_t arc_stats = {
 	{ "memory_throttle_count",	KSTAT_DATA_UINT64 },
 	{ "duplicate_buffers",		KSTAT_DATA_UINT64 },
 	{ "duplicate_buffers_size",	KSTAT_DATA_UINT64 },
-	{ "duplicate_reads",		KSTAT_DATA_UINT64 }
+	{ "duplicate_reads",		KSTAT_DATA_UINT64 },
+	{ "arc_meta_used",		KSTAT_DATA_UINT64 },
+	{ "arc_meta_limit",		KSTAT_DATA_UINT64 },
+	{ "arc_meta_max",		KSTAT_DATA_UINT64 }
 };
 
 #define	ARCSTAT(stat)	(arc_stats.stat.value.ui64)
@@ -555,6 +571,9 @@ static arc_state_t	*arc_l2c_only;
 #define	arc_c		ARCSTAT(arcstat_c)	/* target size of cache */
 #define	arc_c_min	ARCSTAT(arcstat_c_min)	/* min target cache size */
 #define	arc_c_max	ARCSTAT(arcstat_c_max)	/* max target cache size */
+#define	arc_meta_limit	ARCSTAT(arcstat_meta_limit) /* max size for metadata */
+#define	arc_meta_used	ARCSTAT(arcstat_meta_used) /* size of metadata */
+#define	arc_meta_max	ARCSTAT(arcstat_meta_max) /* max size of metadata */
 
 #define	L2ARC_IS_VALID_COMPRESS(_c_) \
 	((_c_) == ZIO_COMPRESS_LZ4 || (_c_) == ZIO_COMPRESS_EMPTY)
@@ -562,13 +581,6 @@ static arc_state_t	*arc_l2c_only;
 static int		arc_no_grow;	/* Don't try to grow cache size */
 static uint64_t		arc_tempreserve;
 static uint64_t		arc_loaned_bytes;
-static uint64_t		arc_meta_used;
-static uint64_t		arc_meta_limit;
-static uint64_t		arc_meta_max = 0;
-SYSCTL_UQUAD(_vfs_zfs, OID_AUTO, arc_meta_used, CTLFLAG_RD, &arc_meta_used, 0,
-    "ARC metadata used");
-SYSCTL_UQUAD(_vfs_zfs, OID_AUTO, arc_meta_limit, CTLFLAG_RW, &arc_meta_limit, 0,
-    "ARC metadata limit");
 
 typedef struct l2arc_buf_hdr l2arc_buf_hdr_t;
 
@@ -629,6 +641,26 @@ struct arc_buf_hdr {
 	list_node_t		b_l2node;
 };
 
+#ifdef _KERNEL
+static int
+sysctl_vfs_zfs_arc_meta_limit(SYSCTL_HANDLER_ARGS)
+{
+	uint64_t val;
+	int err;
+
+	val = arc_meta_limit;
+	err = sysctl_handle_64(oidp, &val, 0, req);
+	if (err != 0 || req->newptr == NULL)
+		return (err);
+
+        if (val <= 0 || val > arc_c_max)
+		return (EINVAL);
+
+	arc_meta_limit = val;
+	return (0);
+}
+#endif
+
 static arc_buf_t *arc_eviction_list;
 static kmutex_t arc_eviction_mtx;
 static arc_buf_hdr_t arc_eviction_hdr;
@@ -1482,7 +1514,7 @@ arc_space_consume(uint64_t space, arc_sp
 		break;
 	}
 
-	atomic_add_64(&arc_meta_used, space);
+	ARCSTAT_INCR(arcstat_meta_used, space);
 	atomic_add_64(&arc_size, space);
 }
 
@@ -1509,7 +1541,7 @@ arc_space_return(uint64_t space, arc_spa
 	ASSERT(arc_meta_used >= space);
 	if (arc_meta_max < arc_meta_used)
 		arc_meta_max = arc_meta_used;
-	atomic_add_64(&arc_meta_used, -space);
+	ARCSTAT_INCR(arcstat_meta_used, -space);
 	ASSERT(arc_size >= space);
 	atomic_add_64(&arc_size, -space);
 }