Add a new line to top that provides a brief summary of the ZFS ARC memory

usage on hosts using ZFS.  The new line displays the total amount of RAM
used by the ARC along with the size of MFU, MRU, anonymous (in flight),
headers, and other (miscellaneous) sub-categories.  The line is not
displayed on systems that are not using ZFS.

Reviewed by:	avg, fs@
MFC after:	3 days

1 files changed, 45 insertions, 0 deletions

diff --git a/contrib/top/display.c b/contrib/top/display.c
index 89795c0..e65ae24 100644
--- a/contrib/top/display.c
+++ b/contrib/top/display.c
@@ -66,6 +66,7 @@ char *screenbuf = NULL;
 static char **procstate_names;
 static char **cpustate_names;
 static char **memory_names;
+static char **arc_names;
 static char **swap_names;
 
 static int num_procstates;
@@ -100,6 +101,8 @@ int  x_brkdn =		15;
 int  y_brkdn =		1;
 int  x_mem =		5;
 int  y_mem =		3;
+int  x_arc =		5;
+int  y_arc =		4;
 int  x_swap =		6;
 int  y_swap =		4;
 int  y_message =	5;
@@ -216,6 +219,8 @@ struct statics *statics;
 	num_memory = string_count(memory_names);
 	lmemory = (int *)malloc(num_memory * sizeof(int));
 
+	arc_names = statics->arc_names;
+	
 	/* calculate starting columns where needed */
 	cpustate_total_length = 0;
 	pp = cpustate_names;
@@ -627,6 +632,46 @@ int *stats;
 }
 
 /*
+ *  *_arc(stats) - print "ARC: " followed by the ARC summary string
+ *
+ *  Assumptions:  cursor is on "lastline"
+ *                for i_arc ONLY: cursor is on the previous line
+ */
+char arc_buffer[MAX_COLS];
+
+i_arc(stats)
+
+int *stats;
+
+{
+    if (arc_names == NULL)
+	return (0);
+
+    fputs("\nARC: ", stdout);
+    lastline++;
+
+    /* format and print the memory summary */
+    summary_format(arc_buffer, stats, arc_names);
+    fputs(arc_buffer, stdout);
+}
+
+u_arc(stats)
+
+int *stats;
+
+{
+    static char new[MAX_COLS];
+
+    if (arc_names == NULL)
+	return (0);
+
+    /* format the new line */
+    summary_format(new, stats, arc_names);
+    line_update(arc_buffer, new, x_arc, y_arc);
+}
+
+ 
+/*
  *  *_swap(stats) - print "Swap: " followed by the swap summary string
  *
  *  Assumptions:  cursor is on "lastline"