Remove 'statslock' from dnssec-signzone

Silence Coverity CID 468757 and 468767 (DATA RACE read not locked)
by converting dnssec-signzone to use atomics for statistics counters
rather than using a lock.  This should be marginally faster than
using the lock as well when statistics are requested.

diff --git a/bin/dnssec/dnssec-signzone.c b/bin/dnssec/dnssec-signzone.c
index 1dc09d57bc57fc16ac7fbbc5543b7592eb46b256..84a9574952c3738f2b432d73299da8005fad5652 100644 (file)
--- a/bin/dnssec/dnssec-signzone.c
+++ b/bin/dnssec/dnssec-signzone.c
@@ -140,10 +140,10 @@ static dns_masterformat_t inputformat = dns_masterformat_text;
 static dns_masterformat_t outputformat = dns_masterformat_text;
 static uint32_t rawversion = 1, serialnum = 0;
 static bool snset = false;
-static unsigned int nsigned = 0, nretained = 0, ndropped = 0;
-static unsigned int nverified = 0, nverifyfailed = 0;
+static atomic_uint_fast32_t nsigned = 0, nretained = 0, ndropped = 0;
+static atomic_uint_fast32_t nverified = 0, nverifyfailed = 0;
 static const char *directory = NULL, *dsdir = NULL;
-static isc_mutex_t namelock, statslock;
+static isc_mutex_t namelock;
 static isc_nm_t *netmgr = NULL;
 static isc_loopmgr_t *loopmgr = NULL;
 static dns_db_t *gdb;            /* The database */
@@ -182,11 +182,9 @@ static dns_ttl_t maxttl = 0;
 static bool no_max_check = false;
 static const char *sync_records = "cdnskey,cds:sha-256";
 
-#define INCSTAT(counter)            \
-       if (printstats) {           \
-               LOCK(&statslock);   \
-               counter++;          \
-               UNLOCK(&statslock); \
+#define INCSTAT(counter)                               \
+       if (printstats) {                              \
+               atomic_fetch_add_relaxed(&counter, 1); \
        }
 
 /*%
@@ -3309,21 +3307,24 @@ print_stats(isc_time_t *timer_start, isc_time_t *timer_finish,
        uint64_t sig_ms;  /* Signatures per millisecond */
        FILE *out = output_stdout ? stderr : stdout;
 
-       fprintf(out, "Signatures generated:               %10u\n", nsigned);
-       fprintf(out, "Signatures retained:                %10u\n", nretained);
-       fprintf(out, "Signatures dropped:                 %10u\n", ndropped);
-       fprintf(out, "Signatures successfully verified:   %10u\n", nverified);
-       fprintf(out,
-               "Signatures unsuccessfully "
-               "verified: %10u\n",
-               nverifyfailed);
+       fprintf(out, "Signatures generated:               %10" PRIuFAST32 "\n",
+               atomic_load(&nsigned));
+       fprintf(out, "Signatures retained:                %10" PRIuFAST32 "\n",
+               atomic_load(&nretained));
+       fprintf(out, "Signatures dropped:                 %10" PRIuFAST32 "\n",
+               atomic_load(&ndropped));
+       fprintf(out, "Signatures successfully verified:   %10" PRIuFAST32 "\n",
+               atomic_load(&nverified));
+       fprintf(out, "Signatures unsuccessfully verified: %10" PRIuFAST32 "\n",
+               atomic_load(&nverifyfailed));
 
        time_us = isc_time_microdiff(sign_finish, sign_start);
        time_ms = time_us / 1000;
        fprintf(out, "Signing time in seconds:           %7u.%03u\n",
                (unsigned int)(time_ms / 1000), (unsigned int)(time_ms % 1000));
        if (time_us > 0) {
-               sig_ms = ((uint64_t)nsigned * 1000000000) / time_us;
+               sig_ms = ((uint64_t)atomic_load(&nsigned) * 1000000000) /
+                        time_us;
                fprintf(out, "Signatures per second:             %7u.%03u\n",
                        (unsigned int)sig_ms / 1000,
                        (unsigned int)sig_ms % 1000);
@@ -4026,10 +4027,6 @@ main(int argc, char *argv[]) {
 
        isc_mutex_init(&namelock);
 
-       if (printstats) {
-               isc_mutex_init(&statslock);
-       }
-
        presign();
        sign_start = isc_time_now();
        signapex();
@@ -4134,7 +4131,6 @@ main(int argc, char *argv[]) {
                timer_finish = isc_time_now();
                print_stats(&timer_start, &timer_finish, &sign_start,
                            &sign_finish);
-               isc_mutex_destroy(&statslock);
        }
        isc_mutex_destroy(&namelock);