summaryrefslogtreecommitdiff
path: root/Documentation/admin-guide/sysctl
diff options
context:
space:
mode:
authorFeng Tang <feng.tang@intel.com>2024-02-02 16:20:42 +0300
committerAndrew Morton <akpm@linux-foundation.org>2024-02-23 02:38:55 +0300
commit2e3fc6ca521499a985a1829a21759ac25359c0f3 (patch)
tree52552999d8a198094d755328291be4cd13464c0e /Documentation/admin-guide/sysctl
parentac4db926e17a669c788efc89b81a4a0f40648445 (diff)
downloadlinux-2e3fc6ca521499a985a1829a21759ac25359c0f3.tar.xz
panic: add option to dump blocked tasks in panic_print
For debugging kernel panics and other bugs, there is already an option of panic_print to dump all tasks' call stacks. On today's large servers running many containers, there could be thousands of tasks or more, and this will print out huge amount of call stacks, taking a lot of time (for serial console which is main target user case of panic_print). And in many cases, only those several tasks being blocked are key for the panic, so add an option to only dump blocked tasks' call stacks. [akpm@linux-foundation.org: clarify documentation a little] Link: https://lkml.kernel.org/r/20240202132042.3609657-1-feng.tang@intel.com Signed-off-by: Feng Tang <feng.tang@intel.com> Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Josh Poimboeuf <jpoimboe@kernel.org> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'Documentation/admin-guide/sysctl')
-rw-r--r--Documentation/admin-guide/sysctl/kernel.rst1
1 files changed, 1 insertions, 0 deletions
diff --git a/Documentation/admin-guide/sysctl/kernel.rst b/Documentation/admin-guide/sysctl/kernel.rst
index bc578663619d..a9b71190399d 100644
--- a/Documentation/admin-guide/sysctl/kernel.rst
+++ b/Documentation/admin-guide/sysctl/kernel.rst
@@ -853,6 +853,7 @@ bit 3 print locks info if ``CONFIG_LOCKDEP`` is on
bit 4 print ftrace buffer
bit 5 print all printk messages in buffer
bit 6 print all CPUs backtrace (if available in the arch)
+bit 7 print only tasks in uninterruptible (blocked) state
===== ============================================
So for example to print tasks and memory info on panic, user can::