Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
stackdepot: Enable context analysis
Enable context analysis for stackdepot.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20251219154418.3592607-32-elver@google.com
authored by
Marco Elver
and committed by
Peter Zijlstra
c3d3023f
0eaa911f
+15
-6
+1
lib/Makefile
+1
lib/Makefile
···
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# Prevent the compiler from calling builtins like memcmp() or bcmp() from this
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# file.
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CFLAGS_stackdepot.o += -fno-builtin
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CONTEXT_ANALYSIS_stackdepot.o := y
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obj-$(CONFIG_STACKDEPOT) += stackdepot.o
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KASAN_SANITIZE_stackdepot.o := n
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# In particular, instrumenting stackdepot.c with KMSAN will result in infinite
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-6
lib/stackdepot.c
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-6
lib/stackdepot.c
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/* Hash mask for indexing the table. */
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static unsigned int stack_hash_mask;
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/* The lock must be held when performing pool or freelist modifications. */
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static DEFINE_RAW_SPINLOCK(pool_lock);
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/* Array of memory regions that store stack records. */
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static void **stack_pools;
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static void **stack_pools __pt_guarded_by(&pool_lock);
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/* Newly allocated pool that is not yet added to stack_pools. */
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static void *new_pool;
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/* Number of pools in stack_pools. */
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static int pools_num;
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/* Offset to the unused space in the currently used pool. */
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static size_t pool_offset = DEPOT_POOL_SIZE;
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static size_t pool_offset __guarded_by(&pool_lock) = DEPOT_POOL_SIZE;
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/* Freelist of stack records within stack_pools. */
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static LIST_HEAD(free_stacks);
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/* The lock must be held when performing pool or freelist modifications. */
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static DEFINE_RAW_SPINLOCK(pool_lock);
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static __guarded_by(&pool_lock) LIST_HEAD(free_stacks);
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/* Statistics counters for debugfs. */
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enum depot_counter_id {
···
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* Initializes new stack pool, and updates the list of pools.
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*/
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static bool depot_init_pool(void **prealloc)
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__must_hold(&pool_lock)
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{
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lockdep_assert_held(&pool_lock);
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···
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/* Keeps the preallocated memory to be used for a new stack depot pool. */
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static void depot_keep_new_pool(void **prealloc)
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__must_hold(&pool_lock)
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{
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lockdep_assert_held(&pool_lock);
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···
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* the current pre-allocation.
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*/
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static struct stack_record *depot_pop_free_pool(void **prealloc, size_t size)
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__must_hold(&pool_lock)
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{
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struct stack_record *stack;
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void *current_pool;
···
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/* Try to find next free usable entry from the freelist. */
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static struct stack_record *depot_pop_free(void)
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__must_hold(&pool_lock)
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{
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struct stack_record *stack;
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···
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/* Allocates a new stack in a stack depot pool. */
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static struct stack_record *
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depot_alloc_stack(unsigned long *entries, unsigned int nr_entries, u32 hash, depot_flags_t flags, void **prealloc)
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__must_hold(&pool_lock)
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{
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struct stack_record *stack = NULL;
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size_t record_size;
···
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}
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static struct stack_record *depot_fetch_stack(depot_stack_handle_t handle)
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__must_not_hold(&pool_lock)
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{
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const int pools_num_cached = READ_ONCE(pools_num);
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union handle_parts parts = { .handle = handle };
···
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return NULL;
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}
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-
pool = stack_pools[pool_index];
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/* @pool_index either valid, or user passed in corrupted value. */
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pool = context_unsafe(stack_pools[pool_index]);
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if (WARN_ON(!pool))
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return NULL;
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···
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/* Links stack into the freelist. */
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static void depot_free_stack(struct stack_record *stack)
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__must_not_hold(&pool_lock)
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{
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unsigned long flags;
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