Both graphics and serial consoles are exposed to hard lockups
when handling a large amount of messaging. The kernel watchdog_thresh
parameter up to now has not been available to be set on the kernel line for
early boot.
This patch allows the setting of watchdog_thresh to be increased
when needed to avoid the hard lockups in the console code.
Signed-off-by: Laurence Oberman <[email protected]>
---
Documentation/admin-guide/kernel-parameters.txt | 8 ++++++++
init/main.c | 9 +++++++++
2 files changed, 17 insertions(+)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 4cdcd1a..cd8d588 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -4932,6 +4932,14 @@
or other driver-specific files in the
Documentation/watchdog/ directory.
+ watchdog_thresh=
+ This parameter is now available as a kernel line
+ parameter. Use watchdog_thresh=30 as example
+ This will allow early boot changes of the current
+ default of 10s to be increased when needed to
+ avoid hard lockups.
+ Default: 10
+
workqueue.watchdog_thresh=
If CONFIG_WQ_WATCHDOG is configured, workqueue can
warn stall conditions and dump internal state to
diff --git a/init/main.c b/init/main.c
index 1c3f902..88cbed9 100644
--- a/init/main.c
+++ b/init/main.c
@@ -1038,6 +1038,15 @@ static int __init set_debug_rodata(char *str)
__setup("rodata=", set_debug_rodata);
#endif
+static int __init
+is_watchdog_thresh_setup(char *str)
+{
+ get_option(&str, &watchdog_thresh);
+ return 1;
+}
+__setup("watchdog_thresh=", is_watchdog_thresh_setup);
+
+
#ifdef CONFIG_STRICT_KERNEL_RWX
static void mark_readonly(void)
{
--
1.8.3.1
On 10/24/18 9:53 AM, Laurence Oberman wrote:
> Both graphics and serial consoles are exposed to hard lockups
> when handling a large amount of messaging. The kernel watchdog_thresh
> parameter up to now has not been available to be set on the kernel line for
> early boot.
> This patch allows the setting of watchdog_thresh to be increased
> when needed to avoid the hard lockups in the console code.
>
> Signed-off-by: Laurence Oberman <[email protected]>
> ---
> Documentation/admin-guide/kernel-parameters.txt | 8 ++++++++
> init/main.c | 9 +++++++++
> 2 files changed, 17 insertions(+)
>
> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
> index 4cdcd1a..cd8d588 100644
> --- a/Documentation/admin-guide/kernel-parameters.txt
> +++ b/Documentation/admin-guide/kernel-parameters.txt
> @@ -4932,6 +4932,14 @@
> or other driver-specific files in the
> Documentation/watchdog/ directory.
>
> + watchdog_thresh=
> + This parameter is now available as a kernel line
> + parameter. Use watchdog_thresh=30 as example
> + This will allow early boot changes of the current
> + default of 10s to be increased when needed to
> + avoid hard lockups.
> + Default: 10
> +
The first sentence isn't needed. and s/10s/10 seconds/
How about this?
This parameter allows early boot to change the default
value of the watchdog timeout threshold from the default
of 10 seconds to avoid hard lockups. Example:
watchdog_thresh=30
> workqueue.watchdog_thresh=
> If CONFIG_WQ_WATCHDOG is configured, workqueue can
> warn stall conditions and dump internal state to
> diff --git a/init/main.c b/init/main.c
> index 1c3f902..88cbed9 100644
> --- a/init/main.c
> +++ b/init/main.c
> @@ -1038,6 +1038,15 @@ static int __init set_debug_rodata(char *str)
> __setup("rodata=", set_debug_rodata);
> #endif
>
> +static int __init
> +is_watchdog_thresh_setup(char *str)
No need to split that into 2 lines; just join them, please.
> +{
> + get_option(&str, &watchdog_thresh);
> + return 1;
> +}
> +__setup("watchdog_thresh=", is_watchdog_thresh_setup);
> +
> +
> #ifdef CONFIG_STRICT_KERNEL_RWX
> static void mark_readonly(void)
> {
>
--
~Randy
Hi Laurence,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on linux-sof-driver/master]
[also build test ERROR on v4.19 next-20181019]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Laurence-Oberman/V3-init-main-c-Enable-watchdog_thresh-control-from-kernel-line/20181025-015902
base: https://github.com/thesofproject/linux master
config: i386-tinyconfig (attached as .config)
compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
reproduce:
# save the attached .config to linux build tree
make ARCH=i386
All errors (new ones prefixed by >>):
init/main.c: In function 'is_watchdog_thresh_setup':
>> init/main.c:1037:20: error: 'watchdog_thresh' undeclared (first use in this function); did you mean 'proc_watchdog_thresh'?
get_option(&str, &watchdog_thresh);
^~~~~~~~~~~~~~~
proc_watchdog_thresh
init/main.c:1037:20: note: each undeclared identifier is reported only once for each function it appears in
vim +1037 init/main.c
1033
1034 static int __init
1035 is_watchdog_thresh_setup(char *str)
1036 {
> 1037 get_option(&str, &watchdog_thresh);
1038 return 1;
1039 }
1040 __setup("watchdog_thresh=", is_watchdog_thresh_setup);
1041
1042
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
On Thu, 2018-10-25 at 02:23 +0800, kbuild test robot wrote:
> Hi Laurence,
>
> Thank you for the patch! Yet something to improve:
>
> [auto build test ERROR on linux-sof-driver/master]
> [also build test ERROR on v4.19 next-20181019]
> [if your patch is applied to the wrong git tree, please drop us a
> note to help improve the system]
>
> url: https://github.com/0day-ci/linux/commits/Laurence-Oberman/V3-
> init-main-c-Enable-watchdog_thresh-control-from-kernel-line/20181025-
> 015902
> base: https://github.com/thesofproject/linux master
> config: i386-tinyconfig (attached as .config)
> compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
> reproduce:
> # save the attached .config to linux build tree
> make ARCH=i386
>
> All errors (new ones prefixed by >>):
>
> init/main.c: In function 'is_watchdog_thresh_setup':
> > > init/main.c:1037:20: error: 'watchdog_thresh' undeclared (first
> > > use in this function); did you mean 'proc_watchdog_thresh'?
>
> get_option(&str, &watchdog_thresh);
> ^~~~~~~~~~~~~~~
> proc_watchdog_thresh
> init/main.c:1037:20: note: each undeclared identifier is reported
> only once for each function it appears in
>
> vim +1037 init/main.c
>
> 1033
> 1034 static int __init
> 1035 is_watchdog_thresh_setup(char *str)
> 1036 {
> > 1037 get_option(&str, &watchdog_thresh);
>
> 1038 return 1;
> 1039 }
> 1040 __setup("watchdog_thresh=", is_watchdog_thresh_setup);
> 1041
> 1042
>
> ---
> 0-DAY kernel test infrastructure Open Source
> Technology Center
> https://lists.01.org/pipermail/kbuild-all Intel
> Corporation
Hello Randy
So I have tested this with no issues, it built clean multiple times
no errors and I was able to set the parameter and I have been using it
for days.
BOOT_IMAGE=(hd0,msdos1)/vmlinuz-4.18.x86_64
root=/dev/mapper/rhel_segstorage3-root ro crashkernel=512M@64M
resume=/dev/mapper/rhel_segstorage3-swap
rd.lvm.lv=rhel_segstorage3/root rd.lvm.lv=rhel_segstorage3/swap
memmap=128G!385G watchdog_thresh=60
[root@segstorage3 ~]# cd /proc/sys/kernel
[root@segstorage3 kernel]# cat watchdog_thresh
60
Do I maybe need the below to avoid the warning
extern int watchdog_thresh;
Thanks
Laurence
Hi Laurence,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on linux-sof-driver/master]
[also build test ERROR on v4.19 next-20181019]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Laurence-Oberman/V3-init-main-c-Enable-watchdog_thresh-control-from-kernel-line/20181025-015902
base: https://github.com/thesofproject/linux master
config: i386-randconfig-s1-201842 (attached as .config)
compiler: gcc-6 (Debian 6.4.0-9) 6.4.0 20171026
reproduce:
# save the attached .config to linux build tree
make ARCH=i386
All errors (new ones prefixed by >>):
init/main.c: In function 'is_watchdog_thresh_setup':
>> init/main.c:1037:20: error: 'watchdog_thresh' undeclared (first use in this function)
get_option(&str, &watchdog_thresh);
^~~~~~~~~~~~~~~
init/main.c:1037:20: note: each undeclared identifier is reported only once for each function it appears in
vim +/watchdog_thresh +1037 init/main.c
1033
1034 static int __init
1035 is_watchdog_thresh_setup(char *str)
1036 {
> 1037 get_option(&str, &watchdog_thresh);
1038 return 1;
1039 }
1040 __setup("watchdog_thresh=", is_watchdog_thresh_setup);
1041
1042
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation