[PATCH 3/3] riscv: Adjust mmap base address at a third of task size

Alexandre Ghiti
2018-12-10T06:25:33Z

This ratio is the most used among all other architectures and make
icache_hygiene libhugetlbfs test pass: this test mmap lots of
hugepages whose addresses, without this patch, reach the end of
the process user address space.

Signed-off-by: Alexandre Ghiti <aghiti@upmem.com>
---
arch/riscv/include/asm/processor.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h
index 0531f49af5c3..ce70bceb8872 100644
--- a/arch/riscv/include/asm/processor.h
+++ b/arch/riscv/include/asm/processor.h
@@ -22,7 +22,7 @@
* This decides where the kernel will search for a free chunk of vm
* space during mmap's.
*/
-#define TASK_UNMAPPED_BASE PAGE_ALIGN(TASK_SIZE >> 1)
+#define TASK_UNMAPPED_BASE PAGE_ALIGN(TASK_SIZE / 3)

#define STACK_TOP TASK_SIZE
#define STACK_TOP_MAX STACK_TOP
--
2.16.2