* [PATCH 1/1] rcutorture: fixes for printing message buffer
@ 2014-07-11 20:30 Pranith Kumar
2014-07-11 20:37 ` Joe Perches
0 siblings, 1 reply; 6+ messages in thread
From: Pranith Kumar @ 2014-07-11 20:30 UTC (permalink / raw)
To: Josh Triplett, Paul E. McKenney, Steven Rostedt,
Mathieu Desnoyers, Lai Jiangshan, Iulia Manda, open list
Cc: Joe Perches
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 <bobby.prani@gmail.com>
cc: Joe Perches <joe@perches.com>
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
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH 1/1] rcutorture: fixes for printing message buffer
2014-07-11 20:30 [PATCH 1/1] rcutorture: fixes for printing message buffer Pranith Kumar
@ 2014-07-11 20:37 ` Joe Perches
2014-07-11 21:09 ` Pranith Kumar
2014-07-14 13:26 ` Pranith Kumar
0 siblings, 2 replies; 6+ messages in thread
From: Joe Perches @ 2014-07-11 20:37 UTC (permalink / raw)
To: Pranith Kumar
Cc: Josh Triplett, Paul E. McKenney, Steven Rostedt,
Mathieu Desnoyers, Lai Jiangshan, Iulia Manda, open list
On Fri, 2014-07-11 at 16:30 -0400, Pranith Kumar wrote:
> 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:
Did you see the patch I sent you?
https://lkml.org/lkml/2014/6/20/604
It doesn't need a vmalloc.
What is wrong with that approach?
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 1/1] rcutorture: fixes for printing message buffer
2014-07-11 20:37 ` Joe Perches
@ 2014-07-11 21:09 ` Pranith Kumar
2014-07-11 21:14 ` Joe Perches
2014-07-14 13:26 ` Pranith Kumar
1 sibling, 1 reply; 6+ messages in thread
From: Pranith Kumar @ 2014-07-11 21:09 UTC (permalink / raw)
To: Joe Perches
Cc: Josh Triplett, Paul E. McKenney, Steven Rostedt,
Mathieu Desnoyers, Lai Jiangshan, Iulia Manda, open list
On Fri, Jul 11, 2014 at 4:37 PM, Joe Perches <joe@perches.com> wrote:
> On Fri, 2014-07-11 at 16:30 -0400, Pranith Kumar wrote:
>> 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:
>
> Did you see the patch I sent you?
> https://lkml.org/lkml/2014/6/20/604
>
> It doesn't need a vmalloc.
> What is wrong with that approach?
>
>
I was trying to stay as close to the original code as possible by
using a buffer instead of using pr_alert/pr_cont throughout the code.
I see nothing wrong with what you proposed, but I like having one
pr_alert instead of lots sprinkled. Also avoiding vmalloc/vfree using
your approach seems like a win.
I will let Paul decide.
--
Pranith
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 1/1] rcutorture: fixes for printing message buffer
2014-07-11 21:09 ` Pranith Kumar
@ 2014-07-11 21:14 ` Joe Perches
0 siblings, 0 replies; 6+ messages in thread
From: Joe Perches @ 2014-07-11 21:14 UTC (permalink / raw)
To: Pranith Kumar
Cc: Josh Triplett, Paul E. McKenney, Steven Rostedt,
Mathieu Desnoyers, Lai Jiangshan, Iulia Manda, open list
On Fri, 2014-07-11 at 17:09 -0400, Pranith Kumar wrote:
> On Fri, Jul 11, 2014 at 4:37 PM, Joe Perches <joe@perches.com> wrote:
> > On Fri, 2014-07-11 at 16:30 -0400, Pranith Kumar wrote:
> >> 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.
[]
> > Did you see the patch I sent you?
> > https://lkml.org/lkml/2014/6/20/604
> >
> > It doesn't need a vmalloc.
> > What is wrong with that approach?
[]
> I see nothing wrong with what you proposed, but I like having one
> pr_alert instead of lots sprinkled. Also avoiding vmalloc/vfree using
> your approach seems like a win.
Using any alloc an an intermediate buffer for logging
messages is very unusual.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 1/1] rcutorture: fixes for printing message buffer
2014-07-11 20:37 ` Joe Perches
2014-07-11 21:09 ` Pranith Kumar
@ 2014-07-14 13:26 ` Pranith Kumar
2014-08-13 21:17 ` Paul E. McKenney
1 sibling, 1 reply; 6+ messages in thread
From: Pranith Kumar @ 2014-07-14 13:26 UTC (permalink / raw)
To: Joe Perches
Cc: Josh Triplett, Paul E. McKenney, Steven Rostedt,
Mathieu Desnoyers, Lai Jiangshan, Iulia Manda, open list
On 07/11/2014 04:37 PM, Joe Perches wrote:
> On Fri, 2014-07-11 at 16:30 -0400, Pranith Kumar wrote:
>> 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:
>
> Did you see the patch I sent you?
> https://lkml.org/lkml/2014/6/20/604
>
> It doesn't need a vmalloc.
> What is wrong with that approach?
>
>
Hi Paul,
Please find an alternative patch as suggested by Joe.
>From 0a3050d5ac910cb5f488e0a0dfe44cde06af1259 Mon Sep 17 00:00:00 2001
From: Pranith Kumar <bobby.prani@gmail.com>
Date: Mon, 14 Jul 2014 09:16:15 -0400
Subject: [PATCH 1/1] 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 Percesh <joe@perches.com>
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
---
include/linux/torture.h | 2 +-
kernel/rcu/rcutorture.c | 127 +++++++++++++++++++++---------------------------
kernel/torture.c | 16 +++---
3 files changed, 64 insertions(+), 81 deletions(-)
diff --git a/include/linux/torture.h b/include/linux/torture.h
index 5ca58fc..fec46f8 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);
+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 5ec0452..3e35f1b 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);
+ 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;
@@ -1109,10 +1119,9 @@ 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();
}
@@ -1120,30 +1129,6 @@ rcu_torture_printk(char *page)
}
/*
- * 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
--- 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);
--
2.0.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH 1/1] rcutorture: fixes for printing message buffer
2014-07-14 13:26 ` Pranith Kumar
@ 2014-08-13 21:17 ` Paul E. McKenney
0 siblings, 0 replies; 6+ messages in thread
From: Paul E. McKenney @ 2014-08-13 21:17 UTC (permalink / raw)
To: Pranith Kumar
Cc: Joe Perches, Josh Triplett, Steven Rostedt, Mathieu Desnoyers,
Lai Jiangshan, Iulia Manda, open list
On Mon, Jul 14, 2014 at 09:26:32AM -0400, Pranith Kumar wrote:
> On 07/11/2014 04:37 PM, Joe Perches wrote:
> > On Fri, 2014-07-11 at 16:30 -0400, Pranith Kumar wrote:
> >> 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:
> >
> > Did you see the patch I sent you?
> > https://lkml.org/lkml/2014/6/20/604
> >
> > It doesn't need a vmalloc.
> > What is wrong with that approach?
> >
> >
>
> Hi Paul,
>
> Please find an alternative patch as suggested by Joe.
Queued for 3.18, thank you both!
Thanx, Paul
> >From 0a3050d5ac910cb5f488e0a0dfe44cde06af1259 Mon Sep 17 00:00:00 2001
> From: Pranith Kumar <bobby.prani@gmail.com>
> Date: Mon, 14 Jul 2014 09:16:15 -0400
> Subject: [PATCH 1/1] 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 Percesh <joe@perches.com>
> Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
> ---
> include/linux/torture.h | 2 +-
> kernel/rcu/rcutorture.c | 127 +++++++++++++++++++++---------------------------
> kernel/torture.c | 16 +++---
> 3 files changed, 64 insertions(+), 81 deletions(-)
>
> diff --git a/include/linux/torture.h b/include/linux/torture.h
> index 5ca58fc..fec46f8 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);
> +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 5ec0452..3e35f1b 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);
> + 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;
> @@ -1109,10 +1119,9 @@ 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();
> }
> @@ -1120,30 +1129,6 @@ rcu_torture_printk(char *page)
> }
>
> /*
> - * 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
> --- 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);
>
> --
> 2.0.1
>
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2014-08-13 21:17 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
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2014-07-11 20:30 [PATCH 1/1] rcutorture: fixes for printing message buffer Pranith Kumar
2014-07-11 20:37 ` Joe Perches
2014-07-11 21:09 ` Pranith Kumar
2014-07-11 21:14 ` Joe Perches
2014-07-14 13:26 ` Pranith Kumar
2014-08-13 21:17 ` Paul E. McKenney
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