From 8eb510db2125ab471967819d1f8749162588bba9 Mon Sep 17 00:00:00 2001 From: "Uladzislau Rezki (Sony)" Date: Tue, 7 Jun 2022 11:34:45 +0200 Subject: [PATCH] mm/vmalloc: make link_va()/unlink_va() common to different rb_root Patch series "Reduce a vmalloc internal lock contention preparation work". This small serias is preparation work to implement per-cpu vmalloc allocation in order to reduce a high internal lock contention. This series does not introduce any functional changes, it is only about preparation. This patch (of 5): Currently link_va() and unlik_va(), in order to figure out a tree type, compares a passed root value with a global free_vmap_area_root variable to distinguish the augmented rb-tree from a regular one. It is hard coded since such functions can manipulate only with specific "free_vmap_area_root" tree that represents a global free vmap space. Make it common by introducing "_augment" versions of both internal functions, so it is possible to deal with different trees. There is no functional change as a result of this patch. Link: https://lkml.kernel.org/r/20220607093449.3100-1-urezki@gmail.com Link: https://lkml.kernel.org/r/20220607093449.3100-2-urezki@gmail.com Signed-off-by: Uladzislau Rezki (Sony) Reviewed-by: Baoquan He Cc: Christoph Hellwig Cc: Matthew Wilcox Cc: Nicholas Piggin Cc: Oleksiy Avramchenko Signed-off-by: Andrew Morton --- mm/vmalloc.c | 60 +++++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 48 insertions(+), 12 deletions(-) diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 37939f96d2f4..2504c83814fe 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -910,8 +910,9 @@ get_va_next_sibling(struct rb_node *parent, struct rb_node **link) } static __always_inline void -link_va(struct vmap_area *va, struct rb_root *root, - struct rb_node *parent, struct rb_node **link, struct list_head *head) +__link_va(struct vmap_area *va, struct rb_root *root, + struct rb_node *parent, struct rb_node **link, + struct list_head *head, bool augment) { /* * VA is still not in the list, but we can @@ -925,7 +926,7 @@ link_va(struct vmap_area *va, struct rb_root *root, /* Insert to the rb-tree */ rb_link_node(&va->rb_node, parent, link); - if (root == &free_vmap_area_root) { + if (augment) { /* * Some explanation here. Just perform simple insertion * to the tree. We do not set va->subtree_max_size to @@ -949,12 +950,28 @@ link_va(struct vmap_area *va, struct rb_root *root, } static __always_inline void -unlink_va(struct vmap_area *va, struct rb_root *root) +link_va(struct vmap_area *va, struct rb_root *root, + struct rb_node *parent, struct rb_node **link, + struct list_head *head) +{ + __link_va(va, root, parent, link, head, false); +} + +static __always_inline void +link_va_augment(struct vmap_area *va, struct rb_root *root, + struct rb_node *parent, struct rb_node **link, + struct list_head *head) +{ + __link_va(va, root, parent, link, head, true); +} + +static __always_inline void +__unlink_va(struct vmap_area *va, struct rb_root *root, bool augment) { if (WARN_ON(RB_EMPTY_NODE(&va->rb_node))) return; - if (root == &free_vmap_area_root) + if (augment) rb_erase_augmented(&va->rb_node, root, &free_vmap_area_rb_augment_cb); else @@ -964,6 +981,18 @@ unlink_va(struct vmap_area *va, struct rb_root *root) RB_CLEAR_NODE(&va->rb_node); } +static __always_inline void +unlink_va(struct vmap_area *va, struct rb_root *root) +{ + __unlink_va(va, root, false); +} + +static __always_inline void +unlink_va_augment(struct vmap_area *va, struct rb_root *root) +{ + __unlink_va(va, root, true); +} + #if DEBUG_AUGMENT_PROPAGATE_CHECK /* * Gets called when remove the node and rotate. @@ -1059,7 +1088,7 @@ insert_vmap_area_augment(struct vmap_area *va, link = find_va_links(va, root, NULL, &parent); if (link) { - link_va(va, root, parent, link, head); + link_va_augment(va, root, parent, link, head); augment_tree_propagate_from(va); } } @@ -1076,8 +1105,8 @@ insert_vmap_area_augment(struct vmap_area *va, * ongoing. */ static __always_inline struct vmap_area * -merge_or_add_vmap_area(struct vmap_area *va, - struct rb_root *root, struct list_head *head) +__merge_or_add_vmap_area(struct vmap_area *va, + struct rb_root *root, struct list_head *head, bool augment) { struct vmap_area *sibling; struct list_head *next; @@ -1139,7 +1168,7 @@ merge_or_add_vmap_area(struct vmap_area *va, * "normalized" because of rotation operations. */ if (merged) - unlink_va(va, root); + __unlink_va(va, root, augment); sibling->va_end = va->va_end; @@ -1154,16 +1183,23 @@ merge_or_add_vmap_area(struct vmap_area *va, insert: if (!merged) - link_va(va, root, parent, link, head); + __link_va(va, root, parent, link, head, augment); return va; } +static __always_inline struct vmap_area * +merge_or_add_vmap_area(struct vmap_area *va, + struct rb_root *root, struct list_head *head) +{ + return __merge_or_add_vmap_area(va, root, head, false); +} + static __always_inline struct vmap_area * merge_or_add_vmap_area_augment(struct vmap_area *va, struct rb_root *root, struct list_head *head) { - va = merge_or_add_vmap_area(va, root, head); + va = __merge_or_add_vmap_area(va, root, head, true); if (va) augment_tree_propagate_from(va); @@ -1347,7 +1383,7 @@ adjust_va_to_fit_type(struct vmap_area *va, * V NVA V * |---------------| */ - unlink_va(va, &free_vmap_area_root); + unlink_va_augment(va, &free_vmap_area_root); kmem_cache_free(vmap_area_cachep, va); } else if (type == LE_FIT_TYPE) { /*