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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /kernel/locking/lockdep_internals.h
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'kernel/locking/lockdep_internals.h')
-rw-r--r--kernel/locking/lockdep_internals.h187
1 files changed, 187 insertions, 0 deletions
diff --git a/kernel/locking/lockdep_internals.h b/kernel/locking/lockdep_internals.h
new file mode 100644
index 000000000..d459d624b
--- /dev/null
+++ b/kernel/locking/lockdep_internals.h
@@ -0,0 +1,187 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * kernel/lockdep_internals.h
+ *
+ * Runtime locking correctness validator
+ *
+ * lockdep subsystem internal functions and variables.
+ */
+
+/*
+ * Lock-class usage-state bits:
+ */
+enum lock_usage_bit {
+#define LOCKDEP_STATE(__STATE) \
+ LOCK_USED_IN_##__STATE, \
+ LOCK_USED_IN_##__STATE##_READ, \
+ LOCK_ENABLED_##__STATE, \
+ LOCK_ENABLED_##__STATE##_READ,
+#include "lockdep_states.h"
+#undef LOCKDEP_STATE
+ LOCK_USED,
+ LOCK_USAGE_STATES
+};
+
+/*
+ * Usage-state bitmasks:
+ */
+#define __LOCKF(__STATE) LOCKF_##__STATE = (1 << LOCK_##__STATE),
+
+enum {
+#define LOCKDEP_STATE(__STATE) \
+ __LOCKF(USED_IN_##__STATE) \
+ __LOCKF(USED_IN_##__STATE##_READ) \
+ __LOCKF(ENABLED_##__STATE) \
+ __LOCKF(ENABLED_##__STATE##_READ)
+#include "lockdep_states.h"
+#undef LOCKDEP_STATE
+ __LOCKF(USED)
+};
+
+#define LOCKF_ENABLED_IRQ (LOCKF_ENABLED_HARDIRQ | LOCKF_ENABLED_SOFTIRQ)
+#define LOCKF_USED_IN_IRQ (LOCKF_USED_IN_HARDIRQ | LOCKF_USED_IN_SOFTIRQ)
+
+#define LOCKF_ENABLED_IRQ_READ \
+ (LOCKF_ENABLED_HARDIRQ_READ | LOCKF_ENABLED_SOFTIRQ_READ)
+#define LOCKF_USED_IN_IRQ_READ \
+ (LOCKF_USED_IN_HARDIRQ_READ | LOCKF_USED_IN_SOFTIRQ_READ)
+
+/*
+ * CONFIG_LOCKDEP_SMALL is defined for sparc. Sparc requires .text,
+ * .data and .bss to fit in required 32MB limit for the kernel. With
+ * CONFIG_LOCKDEP we could go over this limit and cause system boot-up problems.
+ * So, reduce the static allocations for lockdeps related structures so that
+ * everything fits in current required size limit.
+ */
+#ifdef CONFIG_LOCKDEP_SMALL
+/*
+ * MAX_LOCKDEP_ENTRIES is the maximum number of lock dependencies
+ * we track.
+ *
+ * We use the per-lock dependency maps in two ways: we grow it by adding
+ * every to-be-taken lock to all currently held lock's own dependency
+ * table (if it's not there yet), and we check it for lock order
+ * conflicts and deadlocks.
+ */
+#define MAX_LOCKDEP_ENTRIES 16384UL
+#define MAX_LOCKDEP_CHAINS_BITS 15
+#define MAX_STACK_TRACE_ENTRIES 262144UL
+#else
+#define MAX_LOCKDEP_ENTRIES 32768UL
+
+#define MAX_LOCKDEP_CHAINS_BITS 16
+
+/*
+ * Stack-trace: tightly packed array of stack backtrace
+ * addresses. Protected by the hash_lock.
+ */
+#define MAX_STACK_TRACE_ENTRIES 524288UL
+#endif
+
+#define MAX_LOCKDEP_CHAINS (1UL << MAX_LOCKDEP_CHAINS_BITS)
+
+#define MAX_LOCKDEP_CHAIN_HLOCKS (MAX_LOCKDEP_CHAINS*5)
+
+extern struct list_head all_lock_classes;
+extern struct lock_chain lock_chains[];
+
+#define LOCK_USAGE_CHARS (1+LOCK_USAGE_STATES/2)
+
+extern void get_usage_chars(struct lock_class *class,
+ char usage[LOCK_USAGE_CHARS]);
+
+extern const char * __get_key_name(struct lockdep_subclass_key *key, char *str);
+
+struct lock_class *lock_chain_get_class(struct lock_chain *chain, int i);
+
+extern unsigned long nr_lock_classes;
+extern unsigned long nr_list_entries;
+extern unsigned long nr_lock_chains;
+extern int nr_chain_hlocks;
+extern unsigned long nr_stack_trace_entries;
+
+extern unsigned int nr_hardirq_chains;
+extern unsigned int nr_softirq_chains;
+extern unsigned int nr_process_chains;
+extern unsigned int max_lockdep_depth;
+extern unsigned int max_recursion_depth;
+
+extern unsigned int max_bfs_queue_depth;
+
+#ifdef CONFIG_PROVE_LOCKING
+extern unsigned long lockdep_count_forward_deps(struct lock_class *);
+extern unsigned long lockdep_count_backward_deps(struct lock_class *);
+#else
+static inline unsigned long
+lockdep_count_forward_deps(struct lock_class *class)
+{
+ return 0;
+}
+static inline unsigned long
+lockdep_count_backward_deps(struct lock_class *class)
+{
+ return 0;
+}
+#endif
+
+#ifdef CONFIG_DEBUG_LOCKDEP
+
+#include <asm/local.h>
+/*
+ * Various lockdep statistics.
+ * We want them per cpu as they are often accessed in fast path
+ * and we want to avoid too much cache bouncing.
+ */
+struct lockdep_stats {
+ int chain_lookup_hits;
+ int chain_lookup_misses;
+ int hardirqs_on_events;
+ int hardirqs_off_events;
+ int redundant_hardirqs_on;
+ int redundant_hardirqs_off;
+ int softirqs_on_events;
+ int softirqs_off_events;
+ int redundant_softirqs_on;
+ int redundant_softirqs_off;
+ int nr_unused_locks;
+ int nr_redundant_checks;
+ int nr_redundant;
+ int nr_cyclic_checks;
+ int nr_cyclic_check_recursions;
+ int nr_find_usage_forwards_checks;
+ int nr_find_usage_forwards_recursions;
+ int nr_find_usage_backwards_checks;
+ int nr_find_usage_backwards_recursions;
+};
+
+DECLARE_PER_CPU(struct lockdep_stats, lockdep_stats);
+
+#define __debug_atomic_inc(ptr) \
+ this_cpu_inc(lockdep_stats.ptr);
+
+#define debug_atomic_inc(ptr) { \
+ WARN_ON_ONCE(!irqs_disabled()); \
+ __this_cpu_inc(lockdep_stats.ptr); \
+}
+
+#define debug_atomic_dec(ptr) { \
+ WARN_ON_ONCE(!irqs_disabled()); \
+ __this_cpu_dec(lockdep_stats.ptr); \
+}
+
+#define debug_atomic_read(ptr) ({ \
+ struct lockdep_stats *__cpu_lockdep_stats; \
+ unsigned long long __total = 0; \
+ int __cpu; \
+ for_each_possible_cpu(__cpu) { \
+ __cpu_lockdep_stats = &per_cpu(lockdep_stats, __cpu); \
+ __total += __cpu_lockdep_stats->ptr; \
+ } \
+ __total; \
+})
+#else
+# define __debug_atomic_inc(ptr) do { } while (0)
+# define debug_atomic_inc(ptr) do { } while (0)
+# define debug_atomic_dec(ptr) do { } while (0)
+# define debug_atomic_read(ptr) 0
+#endif