lib: stackdepot: add support to disable stack depot
authorVijayanand Jitta <vjitta@codeaurora.org>
Fri, 26 Feb 2021 01:21:27 +0000 (17:21 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 26 Feb 2021 17:41:04 +0000 (09:41 -0800)
commite1fdc403349c64fa58f4c163f4bf9b860b4db808
tree18d2e4c6908552dccc5069f3aa393e39f0ca9655
parentd262093656a0eec6d6114a3178a9d887fddd0ded
lib: stackdepot: add support to disable stack depot

Add a kernel parameter stack_depot_disable to disable stack depot.  So
that stack hash table doesn't consume any memory when stack depot is
disabled.

The use case is CONFIG_PAGE_OWNER without page_owner=on.  Without this
patch, stackdepot will consume the memory for the hashtable.  By default,
it's 8M which is never trivial.

With this option, in CONFIG_PAGE_OWNER configured system, page_owner=off,
stack_depot_disable in kernel command line, we could save the wasted
memory for the hashtable.

[akpm@linux-foundation.org: fix CONFIG_STACKDEPOT=n build]

Link: https://lkml.kernel.org/r/1611749198-24316-2-git-send-email-vjitta@codeaurora.org
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
Signed-off-by: Vijayanand Jitta <vjitta@codeaurora.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Yogesh Lal <ylal@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Documentation/admin-guide/kernel-parameters.txt
include/linux/stackdepot.h
init/main.c
lib/stackdepot.c