-/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
- * vim:expandtab:shiftwidth=8:tabstop=8:
- *
+/*
* GPL HEADER START
*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
* GPL HEADER END
*/
/*
- * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
+ * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
* Use is subject to license terms.
+ *
+ * Copyright (c) 2012, Intel Corporation.
*/
/*
* This file is part of Lustre, http://www.lustre.org/
*/
#define DEBUG_SUBSYSTEM S_CLASS
-#ifndef EXPORT_SYMTAB
-# define EXPORT_SYMTAB
-#endif
-
-#ifdef __KERNEL__
-# include <libcfs/libcfs.h>
-#else
-# include <liblustre.h>
-#endif
+#include <libcfs/libcfs.h>
#include <obd.h>
#include <obd_class.h>
#include <obd_support.h>
#ifdef USE_LU_REF
-struct lu_ref_link {
- struct lu_ref *ll_ref;
- struct list_head ll_linkage;
- const char *ll_scope;
- const void *ll_source;
-};
+/**
+ * Asserts a condition for a given lu_ref. Must be called with
+ * lu_ref::lf_guard held.
+ */
+#define REFASSERT(ref, expr) do { \
+ struct lu_ref *__tmp = (ref); \
+ \
+ if (unlikely(!(expr))) { \
+ lu_ref_print(__tmp); \
+ spin_unlock(&__tmp->lf_guard); \
+ lu_ref_print_all(); \
+ LASSERT(0); \
+ spin_lock(&__tmp->lf_guard); \
+ } \
+} while (0)
-static cfs_mem_cache_t *lu_ref_link_kmem;
+static struct kmem_cache *lu_ref_link_kmem;
static struct lu_kmem_descr lu_ref_caches[] = {
{
}
};
+/**
+ * Global list of active (initialized, but not finalized) lu_ref's.
+ *
+ * Protected by lu_ref_refs_guard.
+ */
+static struct list_head lu_ref_refs;
+static spinlock_t lu_ref_refs_guard;
+static struct lu_ref lu_ref_marker = {
+ .lf_guard = __SPIN_LOCK_UNLOCKED(lu_ref_marker.lf_guard),
+ .lf_list = LIST_HEAD_INIT(lu_ref_marker.lf_list),
+ .lf_linkage = LIST_HEAD_INIT(lu_ref_marker.lf_linkage)
+};
+
void lu_ref_print(const struct lu_ref *ref)
{
struct lu_ref_link *link;
- CERROR("lu_ref: %p %d\n", ref, ref->lf_failed);
- list_for_each_entry(link, &ref->lf_list, ll_linkage) {
+ CERROR("lu_ref: %p %d %d %s:%d\n",
+ ref, ref->lf_refs, ref->lf_failed, ref->lf_func, ref->lf_line);
+ list_for_each_entry(link, &ref->lf_list, ll_linkage) {
CERROR(" link: %s %p\n", link->ll_scope, link->ll_source);
}
}
EXPORT_SYMBOL(lu_ref_print);
-void lu_ref_init(struct lu_ref *ref)
+static int lu_ref_is_marker(const struct lu_ref *ref)
+{
+ return (ref == &lu_ref_marker);
+}
+
+void lu_ref_print_all(void)
+{
+ struct lu_ref *ref;
+
+ spin_lock(&lu_ref_refs_guard);
+ list_for_each_entry(ref, &lu_ref_refs, lf_linkage) {
+ if (lu_ref_is_marker(ref))
+ continue;
+
+ spin_lock(&ref->lf_guard);
+ lu_ref_print(ref);
+ spin_unlock(&ref->lf_guard);
+ }
+ spin_unlock(&lu_ref_refs_guard);
+}
+EXPORT_SYMBOL(lu_ref_print_all);
+
+void lu_ref_init_loc(struct lu_ref *ref, const char *func, const int line)
{
- spin_lock_init(&ref->lf_guard);
- CFS_INIT_LIST_HEAD(&ref->lf_list);
+ ref->lf_refs = 0;
+ ref->lf_func = func;
+ ref->lf_line = line;
+ spin_lock_init(&ref->lf_guard);
+ INIT_LIST_HEAD(&ref->lf_list);
+ spin_lock(&lu_ref_refs_guard);
+ list_add(&ref->lf_linkage, &lu_ref_refs);
+ spin_unlock(&lu_ref_refs_guard);
}
-EXPORT_SYMBOL(lu_ref_init);
+EXPORT_SYMBOL(lu_ref_init_loc);
void lu_ref_fini(struct lu_ref *ref)
{
- if (!list_empty(&ref->lf_list)) {
- spin_lock(&ref->lf_guard);
- lu_ref_print(ref);
- spin_unlock(&ref->lf_guard);
- }
- LASSERT(list_empty(&ref->lf_list));
+ REFASSERT(ref, list_empty(&ref->lf_list));
+ REFASSERT(ref, ref->lf_refs == 0);
+ spin_lock(&lu_ref_refs_guard);
+ list_del_init(&ref->lf_linkage);
+ spin_unlock(&lu_ref_refs_guard);
}
EXPORT_SYMBOL(lu_ref_fini);
-int lu_ref_global_init(void);
static struct lu_ref_link *lu_ref_add_context(struct lu_ref *ref,
- enum cfs_alloc_flags flags,
+ int flags,
const char *scope,
const void *source)
{
struct lu_ref_link *link;
- /* this can be called so early in lustre initialization, that
- * lu_ref_link_kmem slab is not yet created. */
- lu_ref_global_init();
-
link = NULL;
if (lu_ref_link_kmem != NULL) {
- OBD_SLAB_ALLOC(link, lu_ref_link_kmem, flags, sizeof(*link));
+ OBD_SLAB_ALLOC_PTR_GFP(link, lu_ref_link_kmem, flags);
if (link != NULL) {
link->ll_ref = ref;
link->ll_scope = scope;
link->ll_source = source;
- spin_lock(&ref->lf_guard);
- list_add_tail(&link->ll_linkage, &ref->lf_list);
- spin_unlock(&ref->lf_guard);
- }
- }
+ spin_lock(&ref->lf_guard);
+ list_add_tail(&link->ll_linkage, &ref->lf_list);
+ ref->lf_refs++;
+ spin_unlock(&ref->lf_guard);
+ }
+ }
- if (link == NULL) {
- spin_lock(&ref->lf_guard);
- ref->lf_failed++;
- spin_unlock(&ref->lf_guard);
- link = ERR_PTR(-ENOMEM);
- }
- return link;
+ if (link == NULL) {
+ spin_lock(&ref->lf_guard);
+ ref->lf_failed++;
+ spin_unlock(&ref->lf_guard);
+ link = ERR_PTR(-ENOMEM);
+ }
+
+ return link;
}
-struct lu_ref_link *lu_ref_add(struct lu_ref *ref, const char *scope,
- const void *source)
+void lu_ref_add(struct lu_ref *ref, const char *scope, const void *source)
{
- might_sleep();
- return lu_ref_add_context(ref, CFS_ALLOC_STD, scope, source);
+ might_sleep();
+ lu_ref_add_context(ref, GFP_IOFS, scope, source);
}
EXPORT_SYMBOL(lu_ref_add);
+void lu_ref_add_at(struct lu_ref *ref, struct lu_ref_link *link,
+ const char *scope, const void *source)
+{
+ link->ll_ref = ref;
+ link->ll_scope = scope;
+ link->ll_source = source;
+ spin_lock(&ref->lf_guard);
+ list_add_tail(&link->ll_linkage, &ref->lf_list);
+ ref->lf_refs++;
+ spin_unlock(&ref->lf_guard);
+}
+EXPORT_SYMBOL(lu_ref_add_at);
+
/**
* Version of lu_ref_add() to be used in non-blockable contexts.
*/
-struct lu_ref_link *lu_ref_add_atomic(struct lu_ref *ref, const char *scope,
- const void *source)
+void lu_ref_add_atomic(struct lu_ref *ref, const char *scope,
+ const void *source)
{
- return lu_ref_add_context(ref, CFS_ALLOC_ATOMIC, scope, source);
+ lu_ref_add_context(ref, GFP_ATOMIC, scope, source);
}
EXPORT_SYMBOL(lu_ref_add_atomic);
unsigned iterations;
iterations = 0;
- list_for_each_entry(link, &ref->lf_list, ll_linkage) {
+ list_for_each_entry(link, &ref->lf_list, ll_linkage) {
++iterations;
if (lu_ref_link_eq(link, scope, source)) {
if (iterations > lu_ref_chain_max_length) {
- CWARN("Long lu_ref chain %i \"%s\":%p\n",
+ CWARN("Long lu_ref chain %d \"%s\":%p\n",
iterations, scope, source);
lu_ref_chain_max_length = iterations * 3 / 2;
}
void lu_ref_del(struct lu_ref *ref, const char *scope, const void *source)
{
- struct lu_ref_link *link;
+ struct lu_ref_link *link;
- spin_lock(&ref->lf_guard);
- link = lu_ref_find(ref, scope, source);
- if (link != NULL) {
- list_del(&link->ll_linkage);
- spin_unlock(&ref->lf_guard);
- OBD_SLAB_FREE(link, lu_ref_link_kmem, sizeof(*link));
- } else {
- LASSERT(ref->lf_failed > 0);
- ref->lf_failed--;
- spin_unlock(&ref->lf_guard);
- }
+ spin_lock(&ref->lf_guard);
+ link = lu_ref_find(ref, scope, source);
+ if (link != NULL) {
+ list_del(&link->ll_linkage);
+ ref->lf_refs--;
+ spin_unlock(&ref->lf_guard);
+ OBD_SLAB_FREE(link, lu_ref_link_kmem, sizeof(*link));
+ } else {
+ REFASSERT(ref, ref->lf_failed > 0);
+ ref->lf_failed--;
+ spin_unlock(&ref->lf_guard);
+ }
}
EXPORT_SYMBOL(lu_ref_del);
void lu_ref_set_at(struct lu_ref *ref, struct lu_ref_link *link,
- const char *scope,
- const void *source0, const void *source1)
+ const char *scope,
+ const void *source0, const void *source1)
{
- spin_lock(&ref->lf_guard);
- if (link != ERR_PTR(-ENOMEM)) {
- LASSERT(link->ll_ref == ref);
- LASSERT(lu_ref_link_eq(link, scope, source0));
- link->ll_source = source1;
- } else {
- LASSERT(ref->lf_failed > 0);
- }
- spin_unlock(&ref->lf_guard);
+ REFASSERT(ref, link != NULL && !IS_ERR(link));
+
+ spin_lock(&ref->lf_guard);
+ REFASSERT(ref, link->ll_ref == ref);
+ REFASSERT(ref, lu_ref_link_eq(link, scope, source0));
+ link->ll_source = source1;
+ spin_unlock(&ref->lf_guard);
}
EXPORT_SYMBOL(lu_ref_set_at);
void lu_ref_del_at(struct lu_ref *ref, struct lu_ref_link *link,
- const char *scope, const void *source)
+ const char *scope, const void *source)
+{
+ REFASSERT(ref, link != NULL && !IS_ERR(link));
+ spin_lock(&ref->lf_guard);
+ REFASSERT(ref, link->ll_ref == ref);
+ REFASSERT(ref, lu_ref_link_eq(link, scope, source));
+ list_del(&link->ll_linkage);
+ ref->lf_refs--;
+ spin_unlock(&ref->lf_guard);
+}
+EXPORT_SYMBOL(lu_ref_del_at);
+
+#ifdef LPROCFS
+
+static void *lu_ref_seq_start(struct seq_file *seq, loff_t *pos)
{
- if (link != ERR_PTR(-ENOMEM)) {
- LASSERT(link->ll_ref == ref);
- LASSERT(lu_ref_link_eq(link, scope, source));
- spin_lock(&ref->lf_guard);
- list_del(&link->ll_linkage);
- spin_unlock(&ref->lf_guard);
- OBD_SLAB_FREE(link, lu_ref_link_kmem, sizeof(*link));
+ struct lu_ref *ref = seq->private;
+
+ spin_lock(&lu_ref_refs_guard);
+ if (list_empty(&ref->lf_linkage))
+ ref = NULL;
+ spin_unlock(&lu_ref_refs_guard);
+
+ return ref;
+}
+
+static void *lu_ref_seq_next(struct seq_file *seq, void *p, loff_t *pos)
+{
+ struct lu_ref *ref = p;
+ struct lu_ref *next;
+
+ LASSERT(seq->private == p);
+ LASSERT(!list_empty(&ref->lf_linkage));
+
+ spin_lock(&lu_ref_refs_guard);
+ next = list_entry(ref->lf_linkage.next, struct lu_ref, lf_linkage);
+ if (&next->lf_linkage == &lu_ref_refs) {
+ p = NULL;
+ } else {
+ (*pos)++;
+ list_move(&ref->lf_linkage, &next->lf_linkage);
+ }
+ spin_unlock(&lu_ref_refs_guard);
+ return p;
+}
+
+static void lu_ref_seq_stop(struct seq_file *seq, void *p)
+{
+ /* Nothing to do */
+}
+
+
+static int lu_ref_seq_show(struct seq_file *seq, void *p)
+{
+ struct lu_ref *ref = p;
+ struct lu_ref *next;
+
+ spin_lock(&lu_ref_refs_guard);
+ next = list_entry(ref->lf_linkage.next, struct lu_ref, lf_linkage);
+ if ((&next->lf_linkage == &lu_ref_refs) || lu_ref_is_marker(next)) {
+ spin_unlock(&lu_ref_refs_guard);
+ return 0;
+ }
+
+ /* print the entry */
+ spin_lock(&next->lf_guard);
+ seq_printf(seq, "lu_ref: %p %d %d %s:%d\n",
+ next, next->lf_refs, next->lf_failed,
+ next->lf_func, next->lf_line);
+ if (next->lf_refs > 64) {
+ seq_printf(seq, " too many references, skip\n");
} else {
- LASSERT(ref->lf_failed > 0);
- spin_lock(&ref->lf_guard);
- ref->lf_failed--;
- spin_unlock(&ref->lf_guard);
+ struct lu_ref_link *link;
+ int i = 0;
+
+ list_for_each_entry(link, &next->lf_list, ll_linkage)
+ seq_printf(seq, " #%d link: %s %p\n",
+ i++, link->ll_scope, link->ll_source);
}
+ spin_unlock(&next->lf_guard);
+ spin_unlock(&lu_ref_refs_guard);
+
+ return 0;
}
-EXPORT_SYMBOL(lu_ref_del_at);
-static int lu_ref_initialized = 0;
+static struct seq_operations lu_ref_seq_ops = {
+ .start = lu_ref_seq_start,
+ .stop = lu_ref_seq_stop,
+ .next = lu_ref_seq_next,
+ .show = lu_ref_seq_show
+};
+
+static int lu_ref_seq_open(struct inode *inode, struct file *file)
+{
+ struct lu_ref *marker = &lu_ref_marker;
+ int result = 0;
+
+ result = seq_open(file, &lu_ref_seq_ops);
+ if (result == 0) {
+ spin_lock(&lu_ref_refs_guard);
+ if (!list_empty(&marker->lf_linkage))
+ result = -EAGAIN;
+ else
+ list_add(&marker->lf_linkage, &lu_ref_refs);
+ spin_unlock(&lu_ref_refs_guard);
+
+ if (result == 0) {
+ struct seq_file *f = file->private_data;
+ f->private = marker;
+ } else {
+ seq_release(inode, file);
+ }
+ }
+
+ return result;
+}
+
+static int lu_ref_seq_release(struct inode *inode, struct file *file)
+{
+ struct lu_ref *ref = ((struct seq_file *)file->private_data)->private;
+
+ spin_lock(&lu_ref_refs_guard);
+ list_del_init(&ref->lf_linkage);
+ spin_unlock(&lu_ref_refs_guard);
+
+ return seq_release(inode, file);
+}
+
+static struct file_operations lu_ref_dump_fops = {
+ .owner = THIS_MODULE,
+ .open = lu_ref_seq_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = lu_ref_seq_release
+};
+
+#endif /* LPROCFS */
+
int lu_ref_global_init(void)
{
- int result;
-
- if (lu_ref_initialized == 0) {
- lu_ref_initialized = 1;
- CDEBUG(D_CONSOLE,
- "lu_ref tracking is enabled. Performance isn't.\n");
- result = lu_kmem_init(lu_ref_caches);
- } else
- result = 0;
+ int result;
+
+ CDEBUG(D_CONSOLE,
+ "lu_ref tracking is enabled. Performance isn't.\n");
+
+ INIT_LIST_HEAD(&lu_ref_refs);
+ spin_lock_init(&lu_ref_refs_guard);
+ result = lu_kmem_init(lu_ref_caches);
+
+#ifdef LPROCFS
+ if (result == 0) {
+ result = lprocfs_seq_create(proc_lustre_root, "lu_refs",
+ 0444, &lu_ref_dump_fops, NULL);
+ if (result)
+ lu_kmem_fini(lu_ref_caches);
+ }
+#endif /* LPROCFS */
+
return result;
}
void lu_ref_global_fini(void)
{
+#ifdef LPROCFS
+ lprocfs_remove_proc_entry("lu_refs", proc_lustre_root);
+#endif /* LPROCFS */
lu_kmem_fini(lu_ref_caches);
}