From b00884802043d9102ecc2abfdc37a7b35b30e52a Mon Sep 17 00:00:00 2001 From: Kevin Hilman Date: Thu, 28 Mar 2013 22:54:40 +0100 Subject: ARM: 7688/1: add support for context tracking subsystem commit 91d1aa43 (context_tracking: New context tracking susbsystem) generalized parts of the RCU userspace extended quiescent state into the context tracking subsystem. Context tracking is then used to implement adaptive tickless (a.k.a extended nohz) To support the new context tracking subsystem on ARM, the user/kernel boundary transtions need to be instrumented. For exceptions and IRQs in usermode, the existing usr_entry macro is used to instrument the user->kernel transition. For the return to usermode path, the ret_to_user* path is instrumented. Using the usr_entry macro, this covers interrupts in userspace, data abort and prefetch abort exceptions in userspace as well as undefined exceptions in userspace (which is where FP emulation and VFP are handled.) For syscalls, the slow return path is covered by instrumenting the ret_to_user path. In addition, the syscall entry point is instrumented which covers the user->kernel transition for both fast and slow syscalls, and an additional instrumentation point is added for the fast syscall return path (ret_fast_syscall). Cc: Mats Liljegren Cc: Frederic Weisbecker Signed-off-by: Kevin Hilman Signed-off-by: Russell King --- arch/arm/Kconfig | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/arm/Kconfig') diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 5b714695b01b..7dc4cabc34d7 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -59,6 +59,7 @@ config ARM select CLONE_BACKWARDS select OLD_SIGSUSPEND3 select OLD_SIGACTION + select HAVE_CONTEXT_TRACKING help The ARM series is a line of low-power-consumption RISC chip designs licensed by ARM Ltd and targeted at embedded applications and -- cgit v1.2.3