diff options
| -rw-r--r-- | lib/Kconfig | 9 | ||||
| -rw-r--r-- | lib/stackdepot.c | 59 |
2 files changed, 49 insertions, 19 deletions
diff --git a/lib/Kconfig b/lib/Kconfig index eaaad4d85bf2..986ea474836c 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -685,15 +685,6 @@ config STACKDEPOT_ALWAYS_INIT bool select STACKDEPOT -config STACK_HASH_ORDER - int "stack depot hash size (12 => 4KB, 20 => 1024KB)" - range 12 20 - default 20 - depends on STACKDEPOT - help - Select the hash size as a power of 2 for the stackdepot hash table. - Choose a lower value to reduce the memory impact. - config REF_TRACKER bool depends on STACKTRACE_SUPPORT diff --git a/lib/stackdepot.c b/lib/stackdepot.c index 5ca0d086ef4a..e73fda23388d 100644 --- a/lib/stackdepot.c +++ b/lib/stackdepot.c @@ -32,6 +32,7 @@ #include <linux/string.h> #include <linux/types.h> #include <linux/memblock.h> +#include <linux/kasan-enabled.h> #define DEPOT_STACK_BITS (sizeof(depot_stack_handle_t) * 8) @@ -145,10 +146,16 @@ depot_alloc_stack(unsigned long *entries, int size, u32 hash, void **prealloc) return stack; } -#define STACK_HASH_SIZE (1L << CONFIG_STACK_HASH_ORDER) -#define STACK_HASH_MASK (STACK_HASH_SIZE - 1) +/* one hash table bucket entry per 16kB of memory */ +#define STACK_HASH_SCALE 14 +/* limited between 4k and 1M buckets */ +#define STACK_HASH_ORDER_MIN 12 +#define STACK_HASH_ORDER_MAX 20 #define STACK_HASH_SEED 0x9747b28c +static unsigned int stack_hash_order; +static unsigned int stack_hash_mask; + static bool stack_depot_disable; static struct stack_record **stack_table; @@ -175,7 +182,7 @@ void __init stack_depot_want_early_init(void) int __init stack_depot_early_init(void) { - size_t size; + unsigned long entries = 0; /* This is supposed to be called only once, from mm_init() */ if (WARN_ON(__stack_depot_early_init_passed)) @@ -183,13 +190,23 @@ int __init stack_depot_early_init(void) __stack_depot_early_init_passed = true; + if (kasan_enabled() && !stack_hash_order) + stack_hash_order = STACK_HASH_ORDER_MAX; + if (!__stack_depot_want_early_init || stack_depot_disable) return 0; - size = (STACK_HASH_SIZE * sizeof(struct stack_record *)); - pr_info("Stack Depot early init allocating hash table with memblock_alloc, %zu bytes\n", - size); - stack_table = memblock_alloc(size, SMP_CACHE_BYTES); + if (stack_hash_order) + entries = 1UL << stack_hash_order; + stack_table = alloc_large_system_hash("stackdepot", + sizeof(struct stack_record *), + entries, + STACK_HASH_SCALE, + HASH_EARLY | HASH_ZERO, + NULL, + &stack_hash_mask, + 1UL << STACK_HASH_ORDER_MIN, + 1UL << STACK_HASH_ORDER_MAX); if (!stack_table) { pr_err("Stack Depot hash table allocation failed, disabling\n"); @@ -207,13 +224,35 @@ int stack_depot_init(void) mutex_lock(&stack_depot_init_mutex); if (!stack_depot_disable && !stack_table) { - pr_info("Stack Depot allocating hash table with kvcalloc\n"); - stack_table = kvcalloc(STACK_HASH_SIZE, sizeof(struct stack_record *), GFP_KERNEL); + unsigned long entries; + int scale = STACK_HASH_SCALE; + + if (stack_hash_order) { + entries = 1UL << stack_hash_order; + } else { + entries = nr_free_buffer_pages(); + entries = roundup_pow_of_two(entries); + + if (scale > PAGE_SHIFT) + entries >>= (scale - PAGE_SHIFT); + else + entries <<= (PAGE_SHIFT - scale); + } + + if (entries < 1UL << STACK_HASH_ORDER_MIN) + entries = 1UL << STACK_HASH_ORDER_MIN; + if (entries > 1UL << STACK_HASH_ORDER_MAX) + entries = 1UL << STACK_HASH_ORDER_MAX; + + pr_info("Stack Depot allocating hash table of %lu entries with kvcalloc\n", + entries); + stack_table = kvcalloc(entries, sizeof(struct stack_record *), GFP_KERNEL); if (!stack_table) { pr_err("Stack Depot hash table allocation failed, disabling\n"); stack_depot_disable = true; ret = -ENOMEM; } + stack_hash_mask = entries - 1; } mutex_unlock(&stack_depot_init_mutex); return ret; @@ -386,7 +425,7 @@ depot_stack_handle_t __stack_depot_save(unsigned long *entries, goto fast_exit; hash = hash_stack(entries, nr_entries); - bucket = &stack_table[hash & STACK_HASH_MASK]; + bucket = &stack_table[hash & stack_hash_mask]; /* * Fast path: look the stack trace up without locking. |