[PATCH 3/3] kernel/hung_task convert hung_task_panic boot parameter to sysctl
From: Vlastimil Babka <hidden>
Date: 2020-03-30 11:56:06
Also in:
linux-mm, lkml
Subsystem:
documentation, filesystems (vfs and infrastructure), hung task detector, proc filesystem, proc sysctl, the rest · Maintainers:
Jonathan Corbet, Alexander Viro, Christian Brauner, Andrew Morton, Lance Yang, Kees Cook, Joel Granados, Linus Torvalds
We can now handle sysctl parameters on kernel command line and have infrastructure to convert legacy command line options that duplicate sysctl to become a sysctl alias. This patch converts the hung_task_panic parameter. Note that the sysctl handler is more strict and allows only 0 and 1, while the legacy parameter allowed any non-zero value. But there is little reason anyone would not be using 1. Signed-off-by: Vlastimil Babka <redacted> --- Documentation/admin-guide/kernel-parameters.txt | 2 +- fs/proc/proc_sysctl.c | 1 + kernel/hung_task.c | 10 ---------- 3 files changed, 2 insertions(+), 11 deletions(-)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 81ff626fc700..e0b8840404a1 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt@@ -1457,7 +1457,7 @@ [KNL] Should the hung task detector generate panics. Format: <integer> - A nonzero value instructs the kernel to panic when a + A value of 1 instructs the kernel to panic when a hung task is detected. The default value is controlled by the CONFIG_BOOTPARAM_HUNG_TASK_PANIC build-time option. The value selected by this boot parameter can
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index 97eb0b552bf8..77b1b844b02b 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c@@ -1743,6 +1743,7 @@ struct sysctl_alias { */ static const struct sysctl_alias sysctl_aliases[] = { {"numa_zonelist_order", "vm.numa_zonelist_order" }, + {"hung_task_panic", "kernel.hung_task_panic" }, { } };
diff --git a/kernel/hung_task.c b/kernel/hung_task.c
index 14a625c16cb3..b22b5eeab3cb 100644
--- a/kernel/hung_task.c
+++ b/kernel/hung_task.c@@ -63,16 +63,6 @@ static struct task_struct *watchdog_task; unsigned int __read_mostly sysctl_hung_task_panic = CONFIG_BOOTPARAM_HUNG_TASK_PANIC_VALUE; -static int __init hung_task_panic_setup(char *str) -{ - int rc = kstrtouint(str, 0, &sysctl_hung_task_panic); - - if (rc) - return rc; - return 1; -} -__setup("hung_task_panic=", hung_task_panic_setup); - static int hung_task_panic(struct notifier_block *this, unsigned long event, void *ptr) {
--
2.25.1