fork: Dynamic Kernel Stack accounting
Add an accounting of amount of stack pages that has been faulted is
currently in use.
Example use case:
$ cat /proc/vmstat | grep stack
nr_kernel_stack 18684
nr_dynamic_stacks_faults 156
The above shows that the kernel stacks use total 18684KiB, out of which
156KiB were faulted in.
Given that the pre-allocated stacks are 4KiB, we can determine the total
number of tasks:
tasks = (nr_kernel_stack - nr_dynamic_stacks_faults) / 4 = 4632.
The amount of kernel stack memory without dynamic stack on this machine
woud be:
4632 * 16 KiB = 74,112 KiB
Therefore, in this example dynamic stacks save: 55,428 KiB
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Link: https://lore.kernel.org/20240311164638.2015063-15-pasha.tatashin@soleen.com
[Rebased]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
3 files changed
