Describe and provide examples for 'print_handle' and 'print_stack'. Signed-off-by: Mauricio Faria de Oliveira --- Documentation/mm/page_owner.rst | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/Documentation/mm/page_owner.rst b/Documentation/mm/page_owner.rst index 3a45a20fc05a..fac14ff2e4a5 100644 --- a/Documentation/mm/page_owner.rst +++ b/Documentation/mm/page_owner.rst @@ -27,7 +27,10 @@ enabled. Other usages are more than welcome. It can also be used to show all the stacks and their current number of allocated base pages, which gives us a quick overview of where the memory is going without the need to screen through all the pages and match the -allocation and free operation. +allocation and free operation. It's also possible to show only a numeric +identifier of all the stacks (without stack traces) and their number of +allocated base pages (faster to read and parse, eg, for monitoring) that +can be matched with stacks later (options print_handle and print_stack). page owner is disabled by default. So, if you'd like to use it, you need to add "page_owner=on" to your boot cmdline. If the kernel is built @@ -95,6 +98,7 @@ Usage ... ... echo 7000 > /sys/kernel/debug/page_owner_stacks/count_threshold + echo 1 > /sys/kernel/debug/page_owner_stacks/print_handle cat /sys/kernel/debug/page_owner_stacks/show_stacks> stacks_7000.txt cat stacks_7000.txt post_alloc_hook+0x177/0x1a0 @@ -113,6 +117,15 @@ Usage __do_sys_finit_module+0x381/0x730 do_syscall_64+0x8d/0x150 entry_SYSCALL_64_after_hwframe+0x62/0x6a + handle: 42 + nr_base_pages: 20824 + ... + + echo 1 > /sys/kernel/debug/page_owner_stacks/print_handle + echo 0 > /sys/kernel/debug/page_owner_stacks/print_stack + cat /sys/kernel/debug/page_owner_stacks/show_stacks > handles_7000.txt + cat handles_7000.txt + handle: 42 nr_base_pages: 20824 ... -- 2.48.1