From 8a8338f6aa79e90e12f6a19aef48c82e3fc55eeb Mon Sep 17 00:00:00 2001 From: Minchan Kim Date: Mon, 11 Mar 2019 11:56:57 +0900 Subject: [PATCH] Revert "mm: introduce CONFIG_SPECULATIVE_PAGE_FAULT" This reverts commit f783633cc8170788da1ce4e2dba6efa35e6147ca. Bug: 128240262 Change-Id: I2d5961521043932a767f828432f28e3418d7a77f Signed-off-by: Minchan Kim [dereference23: Forward port to msm-5.4] Signed-off-by: Alexander Winkowski --- mm/Kconfig | 23 ----------------------- 1 file changed, 23 deletions(-) diff --git a/mm/Kconfig b/mm/Kconfig index b1dc1e321d49..9f2aa4be3595 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -766,29 +766,6 @@ config HAVE_USERSPACE_LOW_MEMORY_KILLER when the OOM killer and userspace memory killer both have the potential to run). -config ARCH_SUPPORTS_SPECULATIVE_PAGE_FAULT - def_bool n - -config SPECULATIVE_PAGE_FAULT - bool "Speculative page faults" - default y - depends on ARCH_SUPPORTS_SPECULATIVE_PAGE_FAULT - depends on MMU && SMP - depends on QGKI - help - Try to handle user space page faults without holding the mmap_sem. - - This should allow better concurrency for massively threaded process - since the page fault handler will not wait for other threads memory - layout change to be done, assuming that this change is done in another - part of the process's memory space. This type of page fault is named - speculative page fault. - - If the speculative page fault fails because of a concurrency is - detected or because underlying PMD or PTE tables are not yet - allocating, it is failing its processing and a classic page fault - is then tried. - config GUP_BENCHMARK bool "Enable infrastructure for get_user_pages_fast() benchmarking" help