Use snprintf() instead of sprintf() for writing to the message buffer. Also use vmalloc() for the allocation of the message buffer. Since pr_alert() is limited to print LOG_LINE_MAX characters at a time, we print the buffer in a loop one line at a time.
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: Pranith Kumar <[email protected]> cc: Joe Perches <[email protected]> Link: https://lkml.org/lkml/2014/6/18/604 --- include/linux/torture.h | 2 +- kernel/rcu/rcutorture.c | 95 +++++++++++++++++++++++++++++++------------------ kernel/torture.c | 7 ++-- 3 files changed, 66 insertions(+), 38 deletions(-) diff --git a/include/linux/torture.h b/include/linux/torture.h index 5ca58fc..1e47ec7 100644 --- 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); +int torture_onoff_stats(char *page, int size); bool torture_onoff_failures(void); /* Low-rider random number generator. */ diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index 5ec0452..ab2cfbd 100644 --- 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); + int (*stats)(char *page, int size); int irq_capable; int can_boost; const char *name; @@ -525,21 +525,23 @@ static void srcu_torture_barrier(void) srcu_barrier(&srcu_ctl); } -static void srcu_torture_stats(char *page) +static int srcu_torture_stats(char *page, int size) { - int cpu; + int cpu, used; int idx = srcu_ctl.completed & 0x1; - page += sprintf(page, "%s%s per-CPU(idx=%d):", + used = snprintf(page, size, "%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); + used += snprintf(page + used, size - used, + " %d(%ld,%ld)", cpu, c0, c1); } - sprintf(page, "\n"); + used += snprintf(page + used, size - used, "\n"); + return used; } static void srcu_torture_synchronize_expedited(void) @@ -1033,10 +1035,10 @@ rcu_torture_reader(void *arg) /* * Create an RCU-torture statistics message in the specified buffer. */ -static void -rcu_torture_printk(char *page) +static int +rcu_torture_printk(char *page, int size) { - int cpu; + int cpu, used = 0; int i; long pipesummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; long batchsummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; @@ -1052,8 +1054,9 @@ rcu_torture_printk(char *page) if (pipesummary[i] != 0) break; } - page += sprintf(page, "%s%s ", torture_type, TORTURE_FLAG); - page += sprintf(page, + used += snprintf(page + used, size - used, + "%s%s ", torture_type, TORTURE_FLAG); + used += snprintf(page + used, size - used, "rtc: %p ver: %lu tfle: %d rta: %d rtaf: %d rtf: %d ", rcu_torture_current, rcu_torture_current_version, @@ -1061,46 +1064,54 @@ rcu_torture_printk(char *page) 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 ", + used += snprintf(page + used, size - used, + "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 ", + used += snprintf(page + used, size - used, + "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", + used += torture_onoff_stats(page + used, size - used); + used += snprintf(page + used, size - used, + "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); + used += snprintf(page + used, size - used, + "\n%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, "!!! "); + used += snprintf(page + used, size - used, "!!! "); atomic_inc(&n_rcu_torture_error); WARN_ON_ONCE(1); } - page += sprintf(page, "Reader Pipe: "); + used += snprintf(page + used, size - used, "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: "); + used += snprintf(page + used, size - used, + " %ld", pipesummary[i]); + used += snprintf(page + used, size - used, + "\n%s%s ", torture_type, TORTURE_FLAG); + used += snprintf(page + used, size - used, "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: "); + used += snprintf(page + used, size - used, + " %ld", batchsummary[i]); + used += snprintf(page + used, size - used, + "\n%s%s ", torture_type, TORTURE_FLAG); + used += snprintf(page + used, size - used, "Free-Block Circulation: "); for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { - page += sprintf(page, " %d", + used += snprintf(page + used, size - used, " %d", atomic_read(&rcu_torture_wcount[i])); } - page += sprintf(page, "\n"); + used += snprintf(page + used, size - used, "\n"); if (cur_ops->stats) - cur_ops->stats(page); + used += cur_ops->stats(page + used, size - used); if (rtcv_snap == rcu_torture_current_version && rcu_torture_current != NULL) { int __maybe_unused flags; @@ -1109,7 +1120,7 @@ rcu_torture_printk(char *page) rcutorture_get_gp_data(cur_ops->ttype, &flags, &gpnum, &completed); - page += sprintf(page, + used += snprintf(page + used, size - used, "??? Writer stall state %d g%lu c%lu f%#x\n", rcu_torture_writer_state, gpnum, completed, flags); @@ -1117,6 +1128,8 @@ rcu_torture_printk(char *page) rcutorture_trace_dump(); } rtcv_snap = rcu_torture_current_version; + + return used; } /* @@ -1130,17 +1143,31 @@ rcu_torture_printk(char *page) static void rcu_torture_stats_print(void) { - int size = nr_cpu_ids * 200 + 8192; - char *buf; + int size = nr_cpu_ids * 200 + 8192, used, marker; + char *buf, *tmpbuf, c; - buf = kmalloc(size, GFP_KERNEL); + buf = vmalloc(size); if (!buf) { pr_err("rcu-torture: Out of memory, need: %d", size); return; } - rcu_torture_printk(buf); - pr_alert("%s", buf); - kfree(buf); + used = rcu_torture_printk(buf, size); + + tmpbuf = buf; + + /* printk() can print only LOG_LINE_MAX chars at a time + * so print the buffer in a loop, one line at a time + */ + while (used > 0) { + marker = strcspn(tmpbuf, "\n") + 1; + c = tmpbuf[marker]; + tmpbuf[marker] = '\0'; + pr_alert("%s", tmpbuf); + tmpbuf[marker] = c; + used -= marker; + tmpbuf += marker; + } + vfree(buf); } /* diff --git a/kernel/torture.c b/kernel/torture.c index d600af2..83de502 100644 --- a/kernel/torture.c +++ b/kernel/torture.c @@ -211,10 +211,11 @@ EXPORT_SYMBOL_GPL(torture_onoff_cleanup); /* * Print online/offline testing statistics. */ -char *torture_onoff_stats(char *page) +int torture_onoff_stats(char *page, int size) { + int used = 0; #ifdef CONFIG_HOTPLUG_CPU - page += sprintf(page, + used = snprintf(page, size, "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, @@ -222,7 +223,7 @@ char *torture_onoff_stats(char *page) min_offline, max_offline, sum_online, sum_offline, HZ); #endif /* #ifdef CONFIG_HOTPLUG_CPU */ - return page; + return used; } EXPORT_SYMBOL_GPL(torture_onoff_stats); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
