mm: send one IPI per CPU to TLB flush all entries after unmapping pages

[cascardo/linux.git] / init / Kconfig

diff --git a/init/Kconfig b/init/Kconfig
index 161acd8..cf7e482 100644 (file)
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -882,6 +882,16 @@ config GENERIC_SCHED_CLOCK
 config ARCH_SUPPORTS_NUMA_BALANCING
        bool
 
+#
+# For architectures that prefer to flush all TLBs after a number of pages
+# are unmapped instead of sending one IPI per page to flush. The architecture
+# must provide guarantees on what happens if a clean TLB cache entry is
+# written after the unmap. Details are in mm/rmap.c near the check for
+# should_defer_flush. The architecture should also consider if the full flush
+# and the refill costs are offset by the savings of sending fewer IPIs.
+config ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
+       bool
+
 #
 # For architectures that know their GCC __int128 support is sound
 #