Commit 536e8b9b authored by Paul E. McKenney's avatar Paul E. McKenney Committed by Boqun Feng
Browse files

srcu: Add FORCE_NEED_SRCU_NMI_SAFE Kconfig for testing 



The srcu_read_lock_nmisafe() and srcu_read_unlock_nmisafe() functions
map to __srcu_read_lock() and __srcu_read_unlock() on systems like x86
that have NMI-safe this_cpu_inc() operations.  This makes the underlying
__srcu_read_lock_nmisafe() and __srcu_read_unlock_nmisafe() functions
difficult to test on (for example) x86 systems, allowing bugs to creep in.

This commit therefore creates a FORCE_NEED_SRCU_NMI_SAFE Kconfig that
forces those underlying functions to be used even on systems where they
are not needed, thus providing better testing coverage.

Signed-off-by: default avatarPaul E. McKenney <paulmck@kernel.org>
Signed-off-by: default avatarBoqun Feng <boqun.feng@gmail.com>
parent 38b43eca

kernel/rcu/Kconfig

+11 −0
Original line number Diff line number Diff line
@@ -65,6 +65,17 @@ config TREE_SRCU 
	help

	  This option selects the full-fledged version of SRCU.



config FORCE_NEED_SRCU_NMI_SAFE

	bool "Force selection of NEED_SRCU_NMI_SAFE"

	depends on !TINY_SRCU

	select NEED_SRCU_NMI_SAFE

	default n

	help

	  This option forces selection of the NEED_SRCU_NMI_SAFE

	  Kconfig option, allowing testing of srcu_read_lock_nmisafe()

	  and srcu_read_unlock_nmisafe() on architectures (like x86)

	  that select the ARCH_HAS_NMI_SAFE_THIS_CPU_OPS Kconfig option.



config NEED_SRCU_NMI_SAFE

	def_bool HAVE_NMI && !ARCH_HAS_NMI_SAFE_THIS_CPU_OPS && !TINY_SRCU