--- /dev/null
+/*
+ * GPL HEADER START
+ *
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 only,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License version 2 for more details (a copy is included
+ * in the LICENSE file that accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License
+ * version 2 along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA
+ *
+ * GPL HEADER END
+ */
+/* Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2011, 2012, Whamcloud, Inc.
+ */
+/*
+ * This file is part of Lustre, http://www.lustre.org/
+ * Lustre is a trademark of Sun Microsystems, Inc.
+ *
+ * Author: liang@whamcloud.com
+ */
+
+#ifndef EXPORT_SYMTAB
+# define EXPORT_SYMTAB
+#endif
+#define DEBUG_SUBSYSTEM S_LNET
+
+#include <libcfs/libcfs.h>
+
+#ifdef __KERNEL__
+
+/** destroy cpu-partition lock, see libcfs_private.h for more detail */
+void
+cfs_percpt_lock_free(struct cfs_percpt_lock *pcl)
+{
+ LASSERT(pcl->pcl_locks != NULL);
+ LASSERT(!pcl->pcl_locked);
+
+ cfs_percpt_free(pcl->pcl_locks);
+ LIBCFS_FREE(pcl, sizeof(*pcl));
+}
+CFS_EXPORT_SYMBOL(cfs_percpt_lock_free);
+
+/**
+ * create cpu-partition lock, see libcfs_private.h for more detail.
+ *
+ * cpu-partition lock is designed for large-scale SMP system, so we need to
+ * reduce cacheline conflict as possible as we can, that's the
+ * reason we always allocate cacheline-aligned memory block.
+ */
+struct cfs_percpt_lock *
+cfs_percpt_lock_alloc(struct cfs_cpt_table *cptab)
+{
+ struct cfs_percpt_lock *pcl;
+ cfs_spinlock_t *lock;
+ int i;
+
+ /* NB: cptab can be NULL, pcl will be for HW CPUs on that case */
+ LIBCFS_ALLOC(pcl, sizeof(*pcl));
+ if (pcl == NULL)
+ return NULL;
+
+ pcl->pcl_cptab = cptab;
+ pcl->pcl_locks = cfs_percpt_alloc(cptab, sizeof(*lock));
+ if (pcl->pcl_locks == NULL) {
+ LIBCFS_FREE(pcl, sizeof(*pcl));
+ return NULL;
+ }
+
+ cfs_percpt_for_each(lock, i, pcl->pcl_locks)
+ cfs_spin_lock_init(lock);
+
+ return pcl;
+}
+CFS_EXPORT_SYMBOL(cfs_percpt_lock_alloc);
+
+/**
+ * lock a CPU partition
+ *
+ * \a index != CFS_PERCPT_LOCK_EX
+ * hold private lock indexed by \a index
+ *
+ * \a index == CFS_PERCPT_LOCK_EX
+ * exclusively lock @pcl and nobody can take private lock
+ */
+void
+cfs_percpt_lock(struct cfs_percpt_lock *pcl, int index)
+{
+ int ncpt = cfs_cpt_number(pcl->pcl_cptab);
+ int i;
+
+ LASSERT(index >= CFS_PERCPT_LOCK_EX && index < ncpt);
+
+ if (ncpt == 1) {
+ index = 0;
+ } else { /* serialize with exclusive lock */
+ while (pcl->pcl_locked)
+ cpu_relax();
+ }
+
+ if (likely(index != CFS_PERCPT_LOCK_EX)) {
+ cfs_spin_lock(pcl->pcl_locks[index]);
+ return;
+ }
+
+ /* exclusive lock request */
+ for (i = 0; i < ncpt; i++) {
+ cfs_spin_lock(pcl->pcl_locks[i]);
+ if (i == 0) {
+ LASSERT(!pcl->pcl_locked);
+ /* nobody should take private lock after this
+ * so I wouldn't starve for too long time */
+ pcl->pcl_locked = 1;
+ }
+ }
+}
+CFS_EXPORT_SYMBOL(cfs_percpt_lock);
+
+/** unlock a CPU partition */
+void
+cfs_percpt_unlock(struct cfs_percpt_lock *pcl, int index)
+{
+ int ncpt = cfs_cpt_number(pcl->pcl_cptab);
+ int i;
+
+ index = ncpt == 1 ? 0 : index;
+
+ if (likely(index != CFS_PERCPT_LOCK_EX)) {
+ cfs_spin_unlock(pcl->pcl_locks[index]);
+ return;
+ }
+
+ for (i = ncpt - 1; i >= 0; i--) {
+ if (i == 0) {
+ LASSERT(pcl->pcl_locked);
+ pcl->pcl_locked = 0;
+ }
+ cfs_spin_unlock(pcl->pcl_locks[i]);
+ }
+}
+CFS_EXPORT_SYMBOL(cfs_percpt_unlock);
+
+#else /* !__KERNEL__ */
+# ifdef HAVE_LIBPTHREAD
+
+struct cfs_percpt_lock *
+cfs_percpt_lock_alloc(struct cfs_cpt_table *cptab)
+{
+ struct cfs_percpt_lock *pcl;
+
+ CFS_ALLOC_PTR(pcl);
+ if (pcl != NULL)
+ pthread_mutex_init(&pcl->pcl_mutex, NULL);
+
+ return pcl;
+}
+
+void
+cfs_percpt_lock_free(struct cfs_percpt_lock *pcl)
+{
+ pthread_mutex_destroy(&pcl->pcl_mutex);
+ CFS_FREE_PTR(pcl);
+}
+
+void
+cfs_percpt_lock(struct cfs_percpt_lock *pcl, int lock)
+{
+ pthread_mutex_lock(&(pcl)->pcl_mutex);
+}
+
+void
+cfs_percpt_unlock(struct cfs_percpt_lock *pcl, int lock)
+{
+ pthread_mutex_unlock(&(pcl)->pcl_mutex);
+}
+
+# else /* !HAVE_LIBPTHREAD */
+
+struct cfs_percpt_lock *
+cfs_percpt_lock_alloc(struct cfs_cpt_table *cptab)
+{
+ return (struct cfs_percpt_lock *)CFS_PERCPT_LOCK_MAGIC;
+}
+
+void
+cfs_percpt_lock_free(struct cfs_percpt_lock *pcl)
+{
+ LASSERT(pcl == (struct cfs_percpt_lock *)CFS_PERCPT_LOCK_MAGIC);
+}
+
+void
+cfs_percpt_lock(struct cfs_percpt_lock *pcl, int index)
+{
+ LASSERT(pcl == (struct cfs_percpt_lock *)CFS_PERCPT_LOCK_MAGIC);
+}
+
+void
+cfs_percpt_unlock(struct cfs_percpt_lock *pcl, int index)
+{
+ LASSERT(pcl == (struct cfs_percpt_lock *)CFS_PERCPT_LOCK_MAGIC);
+}
+
+# endif /* HAVE_LIBPTHREAD */
+#endif /* __KERNEL__ */
+
+/** free cpu-partition refcount */
+void
+cfs_percpt_atomic_free(cfs_atomic_t **refs)
+{
+ cfs_percpt_free(refs);
+}
+CFS_EXPORT_SYMBOL(cfs_percpt_atomic_free);
+
+/** allocate cpu-partition refcount with initial value @init_val */
+cfs_atomic_t **
+cfs_percpt_atomic_alloc(struct cfs_cpt_table *cptab, int init_val)
+{
+ cfs_atomic_t **refs;
+ cfs_atomic_t *ref;
+ int i;
+
+ refs = cfs_percpt_alloc(cptab, sizeof(*ref));
+ if (refs == NULL)
+ return NULL;
+
+ cfs_percpt_for_each(ref, i, refs)
+ cfs_atomic_set(ref, init_val);
+ return refs;
+}
+CFS_EXPORT_SYMBOL(cfs_percpt_atomic_alloc);
+
+/** return sum of cpu-partition refs */
+int
+cfs_percpt_atomic_summary(cfs_atomic_t **refs)
+{
+ cfs_atomic_t *ref;
+ int i;
+ int val = 0;
+
+ cfs_percpt_for_each(ref, i, refs)
+ val += cfs_atomic_read(ref);
+
+ return val;
+}
+CFS_EXPORT_SYMBOL(cfs_percpt_atomic_summary);
git://git.whamcloud.com / fs / lustre-release.git / blobdiff