rcu: Use pr_alert/pr_cont for printing logs

User pr_alert/pr_cont for printing the logs from rcutorture module directly
instead of writing it to a buffer and then printing it. This allows us from not
having to allocate such buffers. Also remove a resulting empty function.

I tested this using the parse-torture.sh script as follows:

$ dmesg | grep torture > log.txt
$ bash parse-torture.sh log.txt test
$

There were no warnings which means that parsing went fine.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

diff --git a/include/linux/torture.h b/include/linux/torture.h
index 5ca58fc..fec46f8 100644 (file)
--- a/include/linux/torture.h
+++ b/include/linux/torture.h
@@ -51,7 +51,7 @@
 
 /* Definitions for online/offline exerciser. */
 int torture_onoff_init(long ooholdoff, long oointerval);
-char *torture_onoff_stats(char *page);
+void torture_onoff_stats(void);
 bool torture_onoff_failures(void);
 
 /* Low-rider random number generator. */

diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 7e67711..ff4f0c7 100644 (file)
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -242,7 +242,7 @@ struct rcu_torture_ops {
        void (*call)(struct rcu_head *head, void (*func)(struct rcu_head *rcu));
        void (*cb_barrier)(void);
        void (*fqs)(void);
-       void (*stats)(char *page);
+       void (*stats)(void);
        int irq_capable;
        int can_boost;
        const char *name;
@@ -525,21 +525,21 @@ static void srcu_torture_barrier(void)
        srcu_barrier(&srcu_ctl);
 }
 
-static void srcu_torture_stats(char *page)
+static void srcu_torture_stats(void)
 {
        int cpu;
        int idx = srcu_ctl.completed & 0x1;
 
-       page += sprintf(page, "%s%s per-CPU(idx=%d):",
-                      torture_type, TORTURE_FLAG, idx);
+       pr_alert("%s%s per-CPU(idx=%d):",
+                torture_type, TORTURE_FLAG, idx);
        for_each_possible_cpu(cpu) {
                long c0, c1;
 
                c0 = (long)per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[!idx];
                c1 = (long)per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[idx];
-               page += sprintf(page, " %d(%ld,%ld)", cpu, c0, c1);
+               pr_cont(" %d(%ld,%ld)", cpu, c0, c1);
        }
-       sprintf(page, "\n");
+       pr_cont("\n");
 }
 
 static void srcu_torture_synchronize_expedited(void)
@@ -1031,10 +1031,15 @@ rcu_torture_reader(void *arg)
 }
 
 /*
- * Create an RCU-torture statistics message in the specified buffer.
+ * Print torture statistics.  Caller must ensure that there is only
+ * one call to this function at a given time!!!  This is normally
+ * accomplished by relying on the module system to only have one copy
+ * of the module loaded, and then by giving the rcu_torture_stats
+ * kthread full control (or the init/cleanup functions when rcu_torture_stats
+ * thread is not running).
  */
 static void
-rcu_torture_printk(char *page)
+rcu_torture_stats_print(void)
 {
        int cpu;
        int i;
@@ -1052,55 +1057,60 @@ rcu_torture_printk(char *page)
                if (pipesummary[i] != 0)
                        break;
        }
-       page += sprintf(page, "%s%s ", torture_type, TORTURE_FLAG);
-       page += sprintf(page,
-                      "rtc: %p ver: %lu tfle: %d rta: %d rtaf: %d rtf: %d ",
-                      rcu_torture_current,
-                      rcu_torture_current_version,
-                      list_empty(&rcu_torture_freelist),
-                      atomic_read(&n_rcu_torture_alloc),
-                      atomic_read(&n_rcu_torture_alloc_fail),
-                      atomic_read(&n_rcu_torture_free));
-       page += sprintf(page, "rtmbe: %d rtbke: %ld rtbre: %ld ",
-                      atomic_read(&n_rcu_torture_mberror),
-                      n_rcu_torture_boost_ktrerror,
-                      n_rcu_torture_boost_rterror);
-       page += sprintf(page, "rtbf: %ld rtb: %ld nt: %ld ",
-                      n_rcu_torture_boost_failure,
-                      n_rcu_torture_boosts,
-                      n_rcu_torture_timers);
-       page = torture_onoff_stats(page);
-       page += sprintf(page, "barrier: %ld/%ld:%ld",
-                      n_barrier_successes,
-                      n_barrier_attempts,
-                      n_rcu_torture_barrier_error);
-       page += sprintf(page, "\n%s%s ", torture_type, TORTURE_FLAG);
+
+       pr_alert("%s%s ", torture_type, TORTURE_FLAG);
+       pr_cont("rtc: %p ver: %lu tfle: %d rta: %d rtaf: %d rtf: %d ",
+               rcu_torture_current,
+               rcu_torture_current_version,
+               list_empty(&rcu_torture_freelist),
+               atomic_read(&n_rcu_torture_alloc),
+               atomic_read(&n_rcu_torture_alloc_fail),
+               atomic_read(&n_rcu_torture_free));
+       pr_cont("rtmbe: %d rtbke: %ld rtbre: %ld ",
+               atomic_read(&n_rcu_torture_mberror),
+               n_rcu_torture_boost_ktrerror,
+               n_rcu_torture_boost_rterror);
+       pr_cont("rtbf: %ld rtb: %ld nt: %ld ",
+               n_rcu_torture_boost_failure,
+               n_rcu_torture_boosts,
+               n_rcu_torture_timers);
+       torture_onoff_stats();
+       pr_cont("barrier: %ld/%ld:%ld\n",
+               n_barrier_successes,
+               n_barrier_attempts,
+               n_rcu_torture_barrier_error);
+
+       pr_alert("%s%s ", torture_type, TORTURE_FLAG);
        if (atomic_read(&n_rcu_torture_mberror) != 0 ||
            n_rcu_torture_barrier_error != 0 ||
            n_rcu_torture_boost_ktrerror != 0 ||
            n_rcu_torture_boost_rterror != 0 ||
            n_rcu_torture_boost_failure != 0 ||
            i > 1) {
-               page += sprintf(page, "!!! ");
+               pr_cont("%s", "!!! ");
                atomic_inc(&n_rcu_torture_error);
                WARN_ON_ONCE(1);
        }
-       page += sprintf(page, "Reader Pipe: ");
+       pr_cont("Reader Pipe: ");
        for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++)
-               page += sprintf(page, " %ld", pipesummary[i]);
-       page += sprintf(page, "\n%s%s ", torture_type, TORTURE_FLAG);
-       page += sprintf(page, "Reader Batch: ");
+               pr_cont(" %ld", pipesummary[i]);
+       pr_cont("\n");
+
+       pr_alert("%s%s ", torture_type, TORTURE_FLAG);
+       pr_cont("Reader Batch: ");
        for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++)
-               page += sprintf(page, " %ld", batchsummary[i]);
-       page += sprintf(page, "\n%s%s ", torture_type, TORTURE_FLAG);
-       page += sprintf(page, "Free-Block Circulation: ");
+               pr_cont(" %ld", batchsummary[i]);
+       pr_cont("\n");
+
+       pr_alert("%s%s ", torture_type, TORTURE_FLAG);
+       pr_cont("Free-Block Circulation: ");
        for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) {
-               page += sprintf(page, " %d",
-                              atomic_read(&rcu_torture_wcount[i]));
+               pr_cont(" %d", atomic_read(&rcu_torture_wcount[i]));
        }
-       page += sprintf(page, "\n");
+       pr_cont("\n");
+
        if (cur_ops->stats)
-               cur_ops->stats(page);
+               cur_ops->stats();
        if (rtcv_snap == rcu_torture_current_version &&
            rcu_torture_current != NULL) {
                int __maybe_unused flags;
@@ -1109,40 +1119,15 @@ rcu_torture_printk(char *page)
 
                rcutorture_get_gp_data(cur_ops->ttype,
                                       &flags, &gpnum, &completed);
-               page += sprintf(page,
-                               "??? Writer stall state %d g%lu c%lu f%#x\n",
-                               rcu_torture_writer_state,
-                               gpnum, completed, flags);
+               pr_alert("??? Writer stall state %d g%lu c%lu f%#x\n",
+                        rcu_torture_writer_state,
+                        gpnum, completed, flags);
                show_rcu_gp_kthreads();
                rcutorture_trace_dump();
        }
        rtcv_snap = rcu_torture_current_version;
 }
 
-/*
- * Print torture statistics.  Caller must ensure that there is only
- * one call to this function at a given time!!!  This is normally
- * accomplished by relying on the module system to only have one copy
- * of the module loaded, and then by giving the rcu_torture_stats
- * kthread full control (or the init/cleanup functions when rcu_torture_stats
- * thread is not running).
- */
-static void
-rcu_torture_stats_print(void)
-{
-       int size = nr_cpu_ids * 200 + 8192;
-       char *buf;
-
-       buf = kmalloc(size, GFP_KERNEL);
-       if (!buf) {
-               pr_err("rcu-torture: Out of memory, need: %d", size);
-               return;
-       }
-       rcu_torture_printk(buf);
-       pr_alert("%s", buf);
-       kfree(buf);
-}
-
 /*
  * Periodically prints torture statistics, if periodic statistics printing
  * was specified via the stat_interval module parameter.

diff --git a/kernel/torture.c b/kernel/torture.c
index d600af2..ede8b25 100644 (file)
--- a/kernel/torture.c
+++ b/kernel/torture.c
@@ -211,18 +211,16 @@ EXPORT_SYMBOL_GPL(torture_onoff_cleanup);
 /*
  * Print online/offline testing statistics.
  */
-char *torture_onoff_stats(char *page)
+void torture_onoff_stats(void)
 {
 #ifdef CONFIG_HOTPLUG_CPU
-       page += sprintf(page,
-                      "onoff: %ld/%ld:%ld/%ld %d,%d:%d,%d %lu:%lu (HZ=%d) ",
-                      n_online_successes, n_online_attempts,
-                      n_offline_successes, n_offline_attempts,
-                      min_online, max_online,
-                      min_offline, max_offline,
-                      sum_online, sum_offline, HZ);
+       pr_cont("onoff: %ld/%ld:%ld/%ld %d,%d:%d,%d %lu:%lu (HZ=%d) ",
+               n_online_successes, n_online_attempts,
+               n_offline_successes, n_offline_attempts,
+               min_online, max_online,
+               min_offline, max_offline,
+               sum_online, sum_offline, HZ);
 #endif /* #ifdef CONFIG_HOTPLUG_CPU */
-       return page;
 }
 EXPORT_SYMBOL_GPL(torture_onoff_stats);