* [PATCH] ARC: [*defconfigs] Enable hung tasks detection
@ 2016-07-21 14:52 Eugeniy Paltsev
2016-07-21 16:17 ` Vineet Gupta
0 siblings, 1 reply; 3+ messages in thread
From: Eugeniy Paltsev @ 2016-07-21 14:52 UTC (permalink / raw)
To: linux-snps-arc
Enable the kernel to detect "hung tasks",
which are bugs that cause the task to be stuck in
uninterruptible "D" state indefinitiley.
Note we're setting HUNG_TASK_TIMEOUT to 10 seconds instead of
default 120 to shorten time required for detection of hung task,
as it set in axs101, axs103 and axs103_smp boards defconfigs.
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev at synopsys.com>
Cc: Christian Ruppert <christian.ruppert at alitech.com>
Cc: Noam Camus <noamca at mellanox.com>
Cc: Vineet Gupta <vgupta at synopsys.com>
Cc: Alexey Brodkin <abrodkin at synopsys.com>
Cc: Zakharov Vlad <vzakhar at synopsys.com>
---
arch/arc/configs/nps_defconfig | 2 ++
arch/arc/configs/nsim_700_defconfig | 2 ++
arch/arc/configs/nsim_hs_defconfig | 2 ++
arch/arc/configs/nsim_hs_smp_defconfig | 2 ++
arch/arc/configs/nsimosci_defconfig | 2 ++
arch/arc/configs/nsimosci_hs_defconfig | 3 +++
arch/arc/configs/nsimosci_hs_smp_defconfig | 3 +++
arch/arc/configs/tb10x_defconfig | 1 +
8 files changed, 17 insertions(+)
diff --git a/arch/arc/configs/nps_defconfig b/arch/arc/configs/nps_defconfig
index ede625c..39ccacd 100644
--- a/arch/arc/configs/nps_defconfig
+++ b/arch/arc/configs/nps_defconfig
@@ -81,4 +81,6 @@ CONFIG_DEBUG_INFO=y
# CONFIG_ENABLE_MUST_CHECK is not set
CONFIG_MAGIC_SYSRQ=y
CONFIG_DEBUG_MEMORY_INIT=y
+CONFIG_DETECT_HUNG_TASK=y
+CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
CONFIG_ENABLE_DEFAULT_TRACERS=y
diff --git a/arch/arc/configs/nsim_700_defconfig b/arch/arc/configs/nsim_700_defconfig
index 7314f53..78c3070 100644
--- a/arch/arc/configs/nsim_700_defconfig
+++ b/arch/arc/configs/nsim_700_defconfig
@@ -61,4 +61,6 @@ CONFIG_TMPFS=y
CONFIG_NFS_FS=y
# CONFIG_ENABLE_WARN_DEPRECATED is not set
# CONFIG_ENABLE_MUST_CHECK is not set
+CONFIG_DETECT_HUNG_TASK=y
+CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
# CONFIG_DEBUG_PREEMPT is not set
diff --git a/arch/arc/configs/nsim_hs_defconfig b/arch/arc/configs/nsim_hs_defconfig
index a99dc7a..c6a0a30 100644
--- a/arch/arc/configs/nsim_hs_defconfig
+++ b/arch/arc/configs/nsim_hs_defconfig
@@ -59,4 +59,6 @@ CONFIG_TMPFS=y
CONFIG_NFS_FS=y
# CONFIG_ENABLE_WARN_DEPRECATED is not set
# CONFIG_ENABLE_MUST_CHECK is not set
+CONFIG_DETECT_HUNG_TASK=y
+CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
# CONFIG_DEBUG_PREEMPT is not set
diff --git a/arch/arc/configs/nsim_hs_smp_defconfig b/arch/arc/configs/nsim_hs_smp_defconfig
index 59f221f..10c5e5e 100644
--- a/arch/arc/configs/nsim_hs_smp_defconfig
+++ b/arch/arc/configs/nsim_hs_smp_defconfig
@@ -58,3 +58,5 @@ CONFIG_TMPFS=y
CONFIG_NFS_FS=y
# CONFIG_ENABLE_WARN_DEPRECATED is not set
# CONFIG_ENABLE_MUST_CHECK is not set
+CONFIG_DETECT_HUNG_TASK=y
+CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
diff --git a/arch/arc/configs/nsimosci_defconfig b/arch/arc/configs/nsimosci_defconfig
index 42bafa5..973ce41 100644
--- a/arch/arc/configs/nsimosci_defconfig
+++ b/arch/arc/configs/nsimosci_defconfig
@@ -71,3 +71,5 @@ CONFIG_TMPFS=y
CONFIG_NFS_FS=y
# CONFIG_ENABLE_WARN_DEPRECATED is not set
# CONFIG_ENABLE_MUST_CHECK is not set
+CONFIG_DETECT_HUNG_TASK=y
+CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
diff --git a/arch/arc/configs/nsimosci_hs_defconfig b/arch/arc/configs/nsimosci_hs_defconfig
index 4bb60c1..c0b99d7 100644
--- a/arch/arc/configs/nsimosci_hs_defconfig
+++ b/arch/arc/configs/nsimosci_hs_defconfig
@@ -70,3 +70,6 @@ CONFIG_TMPFS=y
CONFIG_NFS_FS=y
# CONFIG_ENABLE_WARN_DEPRECATED is not set
# CONFIG_ENABLE_MUST_CHECK is not set
+CONFIG_DEBUG_KERNEL=y
+CONFIG_DETECT_HUNG_TASK=y
+CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
diff --git a/arch/arc/configs/nsimosci_hs_smp_defconfig b/arch/arc/configs/nsimosci_hs_smp_defconfig
index 7e88f4c..4012585 100644
--- a/arch/arc/configs/nsimosci_hs_smp_defconfig
+++ b/arch/arc/configs/nsimosci_hs_smp_defconfig
@@ -84,3 +84,6 @@ CONFIG_NFS_FS=y
# CONFIG_ENABLE_WARN_DEPRECATED is not set
# CONFIG_ENABLE_MUST_CHECK is not set
CONFIG_FTRACE=y
+CONFIG_DEBUG_KERNEL=y
+CONFIG_DETECT_HUNG_TASK=y
+CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
diff --git a/arch/arc/configs/tb10x_defconfig b/arch/arc/configs/tb10x_defconfig
index 4c51183..e8a96eb 100644
--- a/arch/arc/configs/tb10x_defconfig
+++ b/arch/arc/configs/tb10x_defconfig
@@ -104,6 +104,7 @@ CONFIG_MAGIC_SYSRQ=y
CONFIG_DEBUG_MEMORY_INIT=y
CONFIG_DEBUG_STACKOVERFLOW=y
CONFIG_DETECT_HUNG_TASK=y
+CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
CONFIG_SCHEDSTATS=y
CONFIG_TIMER_STATS=y
# CONFIG_CRYPTO_HW is not set
--
2.5.5
^ permalink raw reply related [flat|nested] 3+ messages in thread
* [PATCH] ARC: [*defconfigs] Enable hung tasks detection
2016-07-21 14:52 [PATCH] ARC: [*defconfigs] Enable hung tasks detection Eugeniy Paltsev
@ 2016-07-21 16:17 ` Vineet Gupta
2016-07-21 17:04 ` Eugeniy Paltsev
0 siblings, 1 reply; 3+ messages in thread
From: Vineet Gupta @ 2016-07-21 16:17 UTC (permalink / raw)
To: linux-snps-arc
On 07/21/2016 07:52 AM, Eugeniy Paltsev wrote:
> Enable the kernel to detect "hung tasks",
> which are bugs that cause the task to be stuck in
> uninterruptible "D" state indefinitiley.
spellos above
> Note we're setting HUNG_TASK_TIMEOUT to 10 seconds instead of
> default 120 to shorten time required for detection of hung task,
> as it set in axs101, axs103 and axs103_smp boards defconfigs.
In some of the actual hang scenarios (on FPGA boards atleast) I was debugging, the
hung task seemed redundant actually as I was getting RCU stall msgs as well. Do
you not see something similar.
> Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev at synopsys.com>
>
> Cc: Christian Ruppert <christian.ruppert at alitech.com>
> Cc: Noam Camus <noamca at mellanox.com>
> Cc: Vineet Gupta <vgupta at synopsys.com>
> Cc: Alexey Brodkin <abrodkin at synopsys.com>
> Cc: Zakharov Vlad <vzakhar at synopsys.com>
> ---
> arch/arc/configs/nps_defconfig | 2 ++
> arch/arc/configs/nsim_700_defconfig | 2 ++
> arch/arc/configs/nsim_hs_defconfig | 2 ++
> arch/arc/configs/nsim_hs_smp_defconfig | 2 ++
> arch/arc/configs/nsimosci_defconfig | 2 ++
> arch/arc/configs/nsimosci_hs_defconfig | 3 +++
> arch/arc/configs/nsimosci_hs_smp_defconfig | 3 +++
> arch/arc/configs/tb10x_defconfig | 1 +
> 8 files changed, 17 insertions(+)
>
> diff --git a/arch/arc/configs/nps_defconfig b/arch/arc/configs/nps_defconfig
> index ede625c..39ccacd 100644
> --- a/arch/arc/configs/nps_defconfig
> +++ b/arch/arc/configs/nps_defconfig
> @@ -81,4 +81,6 @@ CONFIG_DEBUG_INFO=y
> # CONFIG_ENABLE_MUST_CHECK is not set
> CONFIG_MAGIC_SYSRQ=y
> CONFIG_DEBUG_MEMORY_INIT=y
> +CONFIG_DETECT_HUNG_TASK=y
> +CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
> CONFIG_ENABLE_DEFAULT_TRACERS=y
> diff --git a/arch/arc/configs/nsim_700_defconfig b/arch/arc/configs/nsim_700_defconfig
> index 7314f53..78c3070 100644
> --- a/arch/arc/configs/nsim_700_defconfig
> +++ b/arch/arc/configs/nsim_700_defconfig
> @@ -61,4 +61,6 @@ CONFIG_TMPFS=y
> CONFIG_NFS_FS=y
> # CONFIG_ENABLE_WARN_DEPRECATED is not set
> # CONFIG_ENABLE_MUST_CHECK is not set
> +CONFIG_DETECT_HUNG_TASK=y
> +CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
> # CONFIG_DEBUG_PREEMPT is not set
> diff --git a/arch/arc/configs/nsim_hs_defconfig b/arch/arc/configs/nsim_hs_defconfig
> index a99dc7a..c6a0a30 100644
> --- a/arch/arc/configs/nsim_hs_defconfig
> +++ b/arch/arc/configs/nsim_hs_defconfig
> @@ -59,4 +59,6 @@ CONFIG_TMPFS=y
> CONFIG_NFS_FS=y
> # CONFIG_ENABLE_WARN_DEPRECATED is not set
> # CONFIG_ENABLE_MUST_CHECK is not set
> +CONFIG_DETECT_HUNG_TASK=y
> +CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
> # CONFIG_DEBUG_PREEMPT is not set
> diff --git a/arch/arc/configs/nsim_hs_smp_defconfig b/arch/arc/configs/nsim_hs_smp_defconfig
> index 59f221f..10c5e5e 100644
> --- a/arch/arc/configs/nsim_hs_smp_defconfig
> +++ b/arch/arc/configs/nsim_hs_smp_defconfig
> @@ -58,3 +58,5 @@ CONFIG_TMPFS=y
> CONFIG_NFS_FS=y
> # CONFIG_ENABLE_WARN_DEPRECATED is not set
> # CONFIG_ENABLE_MUST_CHECK is not set
> +CONFIG_DETECT_HUNG_TASK=y
> +CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
> diff --git a/arch/arc/configs/nsimosci_defconfig b/arch/arc/configs/nsimosci_defconfig
> index 42bafa5..973ce41 100644
> --- a/arch/arc/configs/nsimosci_defconfig
> +++ b/arch/arc/configs/nsimosci_defconfig
> @@ -71,3 +71,5 @@ CONFIG_TMPFS=y
> CONFIG_NFS_FS=y
> # CONFIG_ENABLE_WARN_DEPRECATED is not set
> # CONFIG_ENABLE_MUST_CHECK is not set
> +CONFIG_DETECT_HUNG_TASK=y
> +CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
> diff --git a/arch/arc/configs/nsimosci_hs_defconfig b/arch/arc/configs/nsimosci_hs_defconfig
> index 4bb60c1..c0b99d7 100644
> --- a/arch/arc/configs/nsimosci_hs_defconfig
> +++ b/arch/arc/configs/nsimosci_hs_defconfig
> @@ -70,3 +70,6 @@ CONFIG_TMPFS=y
> CONFIG_NFS_FS=y
> # CONFIG_ENABLE_WARN_DEPRECATED is not set
> # CONFIG_ENABLE_MUST_CHECK is not set
> +CONFIG_DEBUG_KERNEL=y
> +CONFIG_DETECT_HUNG_TASK=y
> +CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
> diff --git a/arch/arc/configs/nsimosci_hs_smp_defconfig b/arch/arc/configs/nsimosci_hs_smp_defconfig
> index 7e88f4c..4012585 100644
> --- a/arch/arc/configs/nsimosci_hs_smp_defconfig
> +++ b/arch/arc/configs/nsimosci_hs_smp_defconfig
> @@ -84,3 +84,6 @@ CONFIG_NFS_FS=y
> # CONFIG_ENABLE_WARN_DEPRECATED is not set
> # CONFIG_ENABLE_MUST_CHECK is not set
> CONFIG_FTRACE=y
> +CONFIG_DEBUG_KERNEL=y
> +CONFIG_DETECT_HUNG_TASK=y
> +CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
> diff --git a/arch/arc/configs/tb10x_defconfig b/arch/arc/configs/tb10x_defconfig
> index 4c51183..e8a96eb 100644
> --- a/arch/arc/configs/tb10x_defconfig
> +++ b/arch/arc/configs/tb10x_defconfig
> @@ -104,6 +104,7 @@ CONFIG_MAGIC_SYSRQ=y
> CONFIG_DEBUG_MEMORY_INIT=y
> CONFIG_DEBUG_STACKOVERFLOW=y
> CONFIG_DETECT_HUNG_TASK=y
> +CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
> CONFIG_SCHEDSTATS=y
> CONFIG_TIMER_STATS=y
> # CONFIG_CRYPTO_HW is not set
>
^ permalink raw reply [flat|nested] 3+ messages in thread
* [PATCH] ARC: [*defconfigs] Enable hung tasks detection
2016-07-21 16:17 ` Vineet Gupta
@ 2016-07-21 17:04 ` Eugeniy Paltsev
0 siblings, 0 replies; 3+ messages in thread
From: Eugeniy Paltsev @ 2016-07-21 17:04 UTC (permalink / raw)
To: linux-snps-arc
Hi,
Not every time. For example, last time I debug mmap3?LTP's test, which?
stuck in "D" state, I didn't recieve any messages until I enabled this
option.?This happends on nsim 700.
On Thu, 2016-07-21@09:17 -0700, Vineet Gupta wrote:
> On 07/21/2016 07:52 AM, Eugeniy Paltsev wrote:
> >
> > Enable the kernel to detect "hung tasks",
> > which are bugs that cause the task to be stuck in
> > uninterruptible "D" state indefinitiley.
> spellos above
>
> >
> > Note we're setting HUNG_TASK_TIMEOUT to 10 seconds instead of
> > default 120 to shorten time required for detection of hung task,
> > as it set in axs101, axs103 and axs103_smp boards defconfigs.
> In some of the actual hang scenarios (on FPGA boards atleast) I was
> debugging, the
> hung task seemed redundant actually as I was getting RCU stall msgs
> as well. Do
> you not see something similar.
>
>
> >
> > Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev at synopsys.com>
> >
> > Cc: Christian Ruppert <christian.ruppert at alitech.com>
> > Cc: Noam Camus <noamca at mellanox.com>
> > Cc: Vineet Gupta <vgupta at synopsys.com>
> > Cc: Alexey Brodkin <abrodkin at synopsys.com>
> > Cc: Zakharov Vlad??<vzakhar at synopsys.com>
> > ---
> > ?arch/arc/configs/nps_defconfig?????????????| 2 ++
> > ?arch/arc/configs/nsim_700_defconfig????????| 2 ++
> > ?arch/arc/configs/nsim_hs_defconfig?????????| 2 ++
> > ?arch/arc/configs/nsim_hs_smp_defconfig?????| 2 ++
> > ?arch/arc/configs/nsimosci_defconfig????????| 2 ++
> > ?arch/arc/configs/nsimosci_hs_defconfig?????| 3 +++
> > ?arch/arc/configs/nsimosci_hs_smp_defconfig | 3 +++
> > ?arch/arc/configs/tb10x_defconfig???????????| 1 +
> > ?8 files changed, 17 insertions(+)
> >
> > diff --git a/arch/arc/configs/nps_defconfig
> > b/arch/arc/configs/nps_defconfig
> > index ede625c..39ccacd 100644
> > --- a/arch/arc/configs/nps_defconfig
> > +++ b/arch/arc/configs/nps_defconfig
> > @@ -81,4 +81,6 @@ CONFIG_DEBUG_INFO=y
> > ?# CONFIG_ENABLE_MUST_CHECK is not set
> > ?CONFIG_MAGIC_SYSRQ=y
> > ?CONFIG_DEBUG_MEMORY_INIT=y
> > +CONFIG_DETECT_HUNG_TASK=y
> > +CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
> > ?CONFIG_ENABLE_DEFAULT_TRACERS=y
> > diff --git a/arch/arc/configs/nsim_700_defconfig
> > b/arch/arc/configs/nsim_700_defconfig
> > index 7314f53..78c3070 100644
> > --- a/arch/arc/configs/nsim_700_defconfig
> > +++ b/arch/arc/configs/nsim_700_defconfig
> > @@ -61,4 +61,6 @@ CONFIG_TMPFS=y
> > ?CONFIG_NFS_FS=y
> > ?# CONFIG_ENABLE_WARN_DEPRECATED is not set
> > ?# CONFIG_ENABLE_MUST_CHECK is not set
> > +CONFIG_DETECT_HUNG_TASK=y
> > +CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
> > ?# CONFIG_DEBUG_PREEMPT is not set
> > diff --git a/arch/arc/configs/nsim_hs_defconfig
> > b/arch/arc/configs/nsim_hs_defconfig
> > index a99dc7a..c6a0a30 100644
> > --- a/arch/arc/configs/nsim_hs_defconfig
> > +++ b/arch/arc/configs/nsim_hs_defconfig
> > @@ -59,4 +59,6 @@ CONFIG_TMPFS=y
> > ?CONFIG_NFS_FS=y
> > ?# CONFIG_ENABLE_WARN_DEPRECATED is not set
> > ?# CONFIG_ENABLE_MUST_CHECK is not set
> > +CONFIG_DETECT_HUNG_TASK=y
> > +CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
> > ?# CONFIG_DEBUG_PREEMPT is not set
> > diff --git a/arch/arc/configs/nsim_hs_smp_defconfig
> > b/arch/arc/configs/nsim_hs_smp_defconfig
> > index 59f221f..10c5e5e 100644
> > --- a/arch/arc/configs/nsim_hs_smp_defconfig
> > +++ b/arch/arc/configs/nsim_hs_smp_defconfig
> > @@ -58,3 +58,5 @@ CONFIG_TMPFS=y
> > ?CONFIG_NFS_FS=y
> > ?# CONFIG_ENABLE_WARN_DEPRECATED is not set
> > ?# CONFIG_ENABLE_MUST_CHECK is not set
> > +CONFIG_DETECT_HUNG_TASK=y
> > +CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
> > diff --git a/arch/arc/configs/nsimosci_defconfig
> > b/arch/arc/configs/nsimosci_defconfig
> > index 42bafa5..973ce41 100644
> > --- a/arch/arc/configs/nsimosci_defconfig
> > +++ b/arch/arc/configs/nsimosci_defconfig
> > @@ -71,3 +71,5 @@ CONFIG_TMPFS=y
> > ?CONFIG_NFS_FS=y
> > ?# CONFIG_ENABLE_WARN_DEPRECATED is not set
> > ?# CONFIG_ENABLE_MUST_CHECK is not set
> > +CONFIG_DETECT_HUNG_TASK=y
> > +CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
> > diff --git a/arch/arc/configs/nsimosci_hs_defconfig
> > b/arch/arc/configs/nsimosci_hs_defconfig
> > index 4bb60c1..c0b99d7 100644
> > --- a/arch/arc/configs/nsimosci_hs_defconfig
> > +++ b/arch/arc/configs/nsimosci_hs_defconfig
> > @@ -70,3 +70,6 @@ CONFIG_TMPFS=y
> > ?CONFIG_NFS_FS=y
> > ?# CONFIG_ENABLE_WARN_DEPRECATED is not set
> > ?# CONFIG_ENABLE_MUST_CHECK is not set
> > +CONFIG_DEBUG_KERNEL=y
> > +CONFIG_DETECT_HUNG_TASK=y
> > +CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
> > diff --git a/arch/arc/configs/nsimosci_hs_smp_defconfig
> > b/arch/arc/configs/nsimosci_hs_smp_defconfig
> > index 7e88f4c..4012585 100644
> > --- a/arch/arc/configs/nsimosci_hs_smp_defconfig
> > +++ b/arch/arc/configs/nsimosci_hs_smp_defconfig
> > @@ -84,3 +84,6 @@ CONFIG_NFS_FS=y
> > ?# CONFIG_ENABLE_WARN_DEPRECATED is not set
> > ?# CONFIG_ENABLE_MUST_CHECK is not set
> > ?CONFIG_FTRACE=y
> > +CONFIG_DEBUG_KERNEL=y
> > +CONFIG_DETECT_HUNG_TASK=y
> > +CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
> > diff --git a/arch/arc/configs/tb10x_defconfig
> > b/arch/arc/configs/tb10x_defconfig
> > index 4c51183..e8a96eb 100644
> > --- a/arch/arc/configs/tb10x_defconfig
> > +++ b/arch/arc/configs/tb10x_defconfig
> > @@ -104,6 +104,7 @@ CONFIG_MAGIC_SYSRQ=y
> > ?CONFIG_DEBUG_MEMORY_INIT=y
> > ?CONFIG_DEBUG_STACKOVERFLOW=y
> > ?CONFIG_DETECT_HUNG_TASK=y
> > +CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
> > ?CONFIG_SCHEDSTATS=y
> > ?CONFIG_TIMER_STATS=y
> > ?# CONFIG_CRYPTO_HW is not set
> >
^ permalink raw reply [flat|nested] 3+ messages in thread
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2016-07-21 14:52 [PATCH] ARC: [*defconfigs] Enable hung tasks detection Eugeniy Paltsev
2016-07-21 16:17 ` Vineet Gupta
2016-07-21 17:04 ` Eugeniy Paltsev
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