From 7e135add24911a9302d9e73fe0456318ce8169fa Mon Sep 17 00:00:00 2001 From: Rui Salvaterra Date: Sun, 22 Aug 2021 14:50:07 +0100 Subject: kernel: disable CONFIG_RCU_EXPERT and friends Based on the existing documentation [1][2], I dare anyone to demonstrate that we need to fine-tune these RCU parameters. The (performance) breakage potential for doing so is immense, so let's just please put down this loaded footgun. Disable CONFIG_RCU_EXPERT and its dependent symbols. Additionally, remove the CONFIG_RCU_EXPERT symbol from the target kconfigs which contain it. [1] https://www.kernel.org/doc/Documentation/RCU/Design/Data-Structures/Data-Structures.html [2] https://lwn.net/Articles/777214/ Signed-off-by: Rui Salvaterra --- target/linux/rockchip/armv8/config-5.10 | 1 - target/linux/rockchip/armv8/config-5.4 | 1 - 2 files changed, 2 deletions(-) (limited to 'target/linux/rockchip') diff --git a/target/linux/rockchip/armv8/config-5.10 b/target/linux/rockchip/armv8/config-5.10 index 3b03333af0..36a3cefaf1 100644 --- a/target/linux/rockchip/armv8/config-5.10 +++ b/target/linux/rockchip/armv8/config-5.10 @@ -483,7 +483,6 @@ CONFIG_RAS=y CONFIG_RATIONAL=y # CONFIG_RAVE_SP_CORE is not set CONFIG_RCU_CPU_STALL_TIMEOUT=21 -# CONFIG_RCU_EXPERT is not set CONFIG_RCU_NEED_SEGCBLIST=y CONFIG_RCU_STALL_COMMON=y CONFIG_RCU_TRACE=y diff --git a/target/linux/rockchip/armv8/config-5.4 b/target/linux/rockchip/armv8/config-5.4 index d3c2cd985a..0a2575adbf 100644 --- a/target/linux/rockchip/armv8/config-5.4 +++ b/target/linux/rockchip/armv8/config-5.4 @@ -463,7 +463,6 @@ CONFIG_RAS=y CONFIG_RATIONAL=y # CONFIG_RAVE_SP_CORE is not set CONFIG_RCU_CPU_STALL_TIMEOUT=21 -# CONFIG_RCU_EXPERT is not set CONFIG_RCU_NEED_SEGCBLIST=y CONFIG_RCU_STALL_COMMON=y CONFIG_RCU_TRACE=y -- cgit v1.2.3