From: "Liam R. Howlett" Subject: radix tree test suite: add pr_err define Patch series "Introducing the Maple Tree". The maple tree is an RCU-safe range based B-tree designed to use modern processor cache efficiently. There are a number of places in the kernel that a non-overlapping range-based tree would be beneficial, especially one with a simple interface. The first user that is covered in this patch set is the vm_area_struct, where three data structures are replaced by the maple tree: the augmented rbtree, the vma cache, and the linked list of VMAs in the mm_struct. The long term goal is to reduce or remove the mmap_lock contention. The tree has a branching factor of 10 for non-leaf nodes and 16 for leaf nodes. With the increased branching factor, it is significantly shorter than the rbtree so it has fewer cache misses. The removal of the linked list between subsequent entries also reduces the cache misses and the need to pull in the previous and next VMA during many tree alterations. This patch (of 70): define pr_err to printk Link: https://lkml.kernel.org/r/20220404143501.2016403-2-Liam.Howlett@oracle.com Link: https://lkml.kernel.org/r/20220426150616.3937571-2-Liam.Howlett@oracle.com Signed-off-by: Liam R. Howlett Signed-off-by: Andrew Morton Cc: Catalin Marinas Cc: David Howells Cc: "Matthew Wilcox (Oracle)" Cc: Vlastimil Babka Cc: Will Deacon Cc: Yu Zhao Signed-off-by: Andrew Morton --- tools/testing/radix-tree/linux/kernel.h | 1 + 1 file changed, 1 insertion(+) --- a/tools/testing/radix-tree/linux/kernel.h~radix-tree-test-suite-add-pr_err-define +++ a/tools/testing/radix-tree/linux/kernel.h @@ -14,6 +14,7 @@ #include "../../../include/linux/kconfig.h" #define printk printf +#define pr_err printk #define pr_info printk #define pr_debug printk #define pr_cont printk _