diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Kconfig.debug | 5 | ||||
| -rw-r--r-- | lib/kobject_uevent.c | 4 | ||||
| -rw-r--r-- | lib/radix-tree.c | 68 | ||||
| -rw-r--r-- | lib/raid6/.gitignore | 4 |
4 files changed, 62 insertions, 19 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 9e06b7f5ecf1..1b4afd2e6ca0 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -994,13 +994,16 @@ config FAULT_INJECTION_STACKTRACE_FILTER config LATENCYTOP bool "Latency measuring infrastructure" + depends on HAVE_LATENCYTOP_SUPPORT + depends on DEBUG_KERNEL + depends on STACKTRACE_SUPPORT + depends on PROC_FS select FRAME_POINTER if !MIPS && !PPC && !S390 && !MICROBLAZE select KALLSYMS select KALLSYMS_ALL select STACKTRACE select SCHEDSTATS select SCHED_DEBUG - depends on HAVE_LATENCYTOP_SUPPORT help Enable this option if you want to use the LatencyTOP tool to find out which userspace is blocking on what kernel operations. diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c index b93579504dfa..70af0a7f97c0 100644 --- a/lib/kobject_uevent.c +++ b/lib/kobject_uevent.c @@ -123,7 +123,7 @@ static int kobj_usermode_filter(struct kobject *kobj) * @kobj: struct kobject that the action is happening to * @envp_ext: pointer to environmental data * - * Returns 0 if kobject_uevent() is completed with success or the + * Returns 0 if kobject_uevent_env() is completed with success or the * corresponding error when it fails. */ int kobject_uevent_env(struct kobject *kobj, enum kobject_action action, @@ -317,7 +317,7 @@ exit: EXPORT_SYMBOL_GPL(kobject_uevent_env); /** - * kobject_uevent - notify userspace by ending an uevent + * kobject_uevent - notify userspace by sending an uevent * * @action: action that is happening * @kobj: struct kobject that the action is happening to diff --git a/lib/radix-tree.c b/lib/radix-tree.c index e907858498a6..efd16fa80b1c 100644 --- a/lib/radix-tree.c +++ b/lib/radix-tree.c @@ -174,14 +174,16 @@ static void radix_tree_node_rcu_free(struct rcu_head *head) { struct radix_tree_node *node = container_of(head, struct radix_tree_node, rcu_head); + int i; /* * must only free zeroed nodes into the slab. radix_tree_shrink * can leave us with a non-NULL entry in the first slot, so clear * that here to make sure. */ - tag_clear(node, 0, 0); - tag_clear(node, 1, 0); + for (i = 0; i < RADIX_TREE_MAX_TAGS; i++) + tag_clear(node, i, 0); + node->slots[0] = NULL; node->count = 0; @@ -623,17 +625,30 @@ EXPORT_SYMBOL(radix_tree_tag_get); * also settag. The function stops either after tagging nr_to_tag items or * after reaching last_index. * + * The tags must be set from the leaf level only and propagated back up the + * path to the root. We must do this so that we resolve the full path before + * setting any tags on intermediate nodes. If we set tags as we descend, then + * we can get to the leaf node and find that the index that has the iftag + * set is outside the range we are scanning. This reults in dangling tags and + * can lead to problems with later tag operations (e.g. livelocks on lookups). + * * The function returns number of leaves where the tag was set and sets * *first_indexp to the first unscanned index. + * WARNING! *first_indexp can wrap if last_index is ULONG_MAX. Caller must + * be prepared to handle that. */ unsigned long radix_tree_range_tag_if_tagged(struct radix_tree_root *root, unsigned long *first_indexp, unsigned long last_index, unsigned long nr_to_tag, unsigned int iftag, unsigned int settag) { - unsigned int height = root->height, shift; - unsigned long tagged = 0, index = *first_indexp; - struct radix_tree_node *open_slots[height], *slot; + unsigned int height = root->height; + struct radix_tree_path path[height]; + struct radix_tree_path *pathp = path; + struct radix_tree_node *slot; + unsigned int shift; + unsigned long tagged = 0; + unsigned long index = *first_indexp; last_index = min(last_index, radix_tree_maxindex(height)); if (index > last_index) @@ -653,6 +668,13 @@ unsigned long radix_tree_range_tag_if_tagged(struct radix_tree_root *root, shift = (height - 1) * RADIX_TREE_MAP_SHIFT; slot = radix_tree_indirect_to_ptr(root->rnode); + /* + * we fill the path from (root->height - 2) to 0, leaving the index at + * (root->height - 1) as a terminator. Zero the node in the terminator + * so that we can use this to end walk loops back up the path. + */ + path[height - 1].node = NULL; + for (;;) { int offset; @@ -661,21 +683,35 @@ unsigned long radix_tree_range_tag_if_tagged(struct radix_tree_root *root, goto next; if (!tag_get(slot, iftag, offset)) goto next; + if (height > 1) { + /* Go down one level */ + height--; + shift -= RADIX_TREE_MAP_SHIFT; + path[height - 1].node = slot; + path[height - 1].offset = offset; + slot = slot->slots[offset]; + continue; + } + + /* tag the leaf */ + tagged++; tag_set(slot, settag, offset); - if (height == 1) { - tagged++; - goto next; + + /* walk back up the path tagging interior nodes */ + pathp = &path[0]; + while (pathp->node) { + /* stop if we find a node with the tag already set */ + if (tag_get(pathp->node, settag, pathp->offset)) + break; + tag_set(pathp->node, settag, pathp->offset); + pathp++; } - /* Go down one level */ - height--; - shift -= RADIX_TREE_MAP_SHIFT; - open_slots[height] = slot; - slot = slot->slots[offset]; - continue; + next: /* Go to next item at level determined by 'shift' */ index = ((index >> shift) + 1) << shift; - if (index > last_index) + /* Overflow can happen when last_index is ~0UL... */ + if (index > last_index || !index) break; if (tagged >= nr_to_tag) break; @@ -685,7 +721,7 @@ next: * last_index is guaranteed to be in the tree, what * we do below cannot wander astray. */ - slot = open_slots[height]; + slot = path[height - 1].node; height++; shift += RADIX_TREE_MAP_SHIFT; } diff --git a/lib/raid6/.gitignore b/lib/raid6/.gitignore new file mode 100644 index 000000000000..162becacf97c --- /dev/null +++ b/lib/raid6/.gitignore @@ -0,0 +1,4 @@ +mktables +altivec*.c +int*.c +tables.c |