From 2a06bf3e95cd93e3640d431960181b8e47415f33 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Sat, 30 Jan 2021 23:08:40 +1000 Subject: powerpc/64: context tracking remove _TIF_NOHZ Add context tracking to the system call handler explicitly, and remove _TIF_NOHZ. This improves system call performance when nohz_full is enabled. On a POWER9, gettid scv system call cost on a nohz_full CPU improves from 1129 cycles to 1004 cycles and on a housekeeping CPU from 550 cycles to 430 cycles. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210130130852.2952424-31-npiggin@gmail.com --- arch/powerpc/Kconfig | 1 - 1 file changed, 1 deletion(-) (limited to 'arch/powerpc/Kconfig') diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index ef64d96bf316..686829dd1c66 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -196,7 +196,6 @@ config PPC select HAVE_STACKPROTECTOR if PPC64 && $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=r13) select HAVE_STACKPROTECTOR if PPC32 && $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=r2) select HAVE_CONTEXT_TRACKING if PPC64 - select HAVE_TIF_NOHZ if PPC64 select HAVE_DEBUG_KMEMLEAK select HAVE_DEBUG_STACKOVERFLOW select HAVE_DYNAMIC_FTRACE -- cgit v1.2.3