nfsstat: Obviate and remove copy_stats().

	Rather than copying stats during --sleep, instead introduce a few
pointers and rearrange them to avoid the copy.  Will be useful with
--since, too.

Signed-off-by: David M. Richter <richterd@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>

diff --git a/utils/nfsstat/nfsstat.c b/utils/nfsstat/nfsstat.c
index ada099e7dae9285c4e2163121fd8207e1223393e..6201f28df8646ab15cbe977ff6409ad7a9fa54f4 100644 (file)
--- a/utils/nfsstat/nfsstat.c
+++ b/utils/nfsstat/nfsstat.c
@@ -164,7 +164,6 @@ static int          mounts(const char *);
 
 static void            get_stats(const char *, statinfo *, int *, int, const char *);
 static int             has_stats(const unsigned int *);
-static void            copy_stats(statinfo *, statinfo *);
 static void            diff_stats(statinfo *, statinfo *);
 static void            unpause(int);
 
@@ -243,6 +242,11 @@ main(int argc, char **argv)
        int             c;
        char           *progname;
 
+       struct statinfo *serverinfo = srvinfo,
+                       *serverinfo_tmp = srvinfo_old,
+                       *clientinfo = cltinfo,
+                       *clientinfo_tmp = cltinfo_old;
+
        struct sigaction act = {
                .sa_handler = unpause,
                .sa_flags = SA_ONESHOT,
@@ -341,31 +345,34 @@ main(int argc, char **argv)
                        "server.\n");
        }
 
+       if (opt_sleep) {
+               serverinfo = srvinfo_old;
+               serverinfo_tmp = srvinfo;
+               clientinfo = cltinfo_old;
+               clientinfo_tmp = cltinfo;
+       }
+
        if (opt_srv)
-               get_stats(NFSSRVSTAT, srvinfo, &opt_srv, opt_clt, "Server");
+               get_stats(NFSSRVSTAT, serverinfo, &opt_srv, opt_clt, "Server");
        if (opt_clt)
-               get_stats(NFSCLTSTAT, cltinfo, &opt_clt, opt_srv, "Client");
+               get_stats(NFSCLTSTAT, clientinfo, &opt_clt, opt_srv, "Client");
 
        /* save stat snapshots; wait for signal; then diff current and saved stats */
        if (opt_sleep) {
                starttime = time(NULL);
                printf("Collecting statistics; press CTRL-C to view results from interval (i.e., from pause to CTRL-C).\n");
-               if (opt_srv)
-                       copy_stats(srvinfo_old, srvinfo);
-               if (opt_clt)
-                       copy_stats(cltinfo_old, cltinfo);
                if (sigaction(SIGINT, &act, NULL) != 0) {
                        fprintf(stderr, "Error: couldn't register for signal and pause.\n");
                        return 1;
                }
                pause();
                if (opt_srv) {
-                       get_stats(NFSSRVSTAT, srvinfo, &opt_srv, opt_clt, "Server");
-                       diff_stats(srvinfo, srvinfo_old);
+                       get_stats(NFSSRVSTAT, serverinfo_tmp, &opt_srv, opt_clt, "Server");
+                       diff_stats(serverinfo_tmp, serverinfo);
                }
                if (opt_clt) {
-                       get_stats(NFSCLTSTAT, cltinfo, &opt_clt, opt_srv, "Client");
-                       diff_stats(cltinfo, cltinfo_old);
+                       get_stats(NFSCLTSTAT, clientinfo_tmp, &opt_clt, opt_srv, "Client");
+                       diff_stats(clientinfo_tmp, clientinfo);
                }
        }
 
@@ -650,20 +657,6 @@ has_stats(const unsigned int *info)
        return (info[0] && info[info[0] + 1] > info[0]);
 }
 
-/* clone 'src' to 'dest' */
-static void
-copy_stats(struct statinfo *dest, struct statinfo *src)
-{
-       int i, j;
-
-       for (i = 0; src[i].tag; i++) {
-               dest[i].tag = src[i].tag;
-               dest[i].nrvals = src[i].nrvals;
-               for (j = 0; j < dest[i].nrvals; j++)
-                       dest[i].valptr[j] = src[i].valptr[j];
-       }
-}
-
 /*
  * take the difference of each individual stat value in 'new' and 'old'
  * and store the results back into 'new'