* Copyright (C) 2009 The Regents of the University of California
* Written by Michael Vrable <mvrable@cs.ucsd.edu>
*
- * TODO: Licensing
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
*/
#include <stdint.h>
#include <glib.h>
#include <string.h>
-#include "bluesky.h"
+#include "bluesky-private.h"
/* Interaction with cloud storage. We expose very simple GET/PUT style
* interface, which different backends can implement. Available backends
- * (will) include Amazon S3 and a simple local store for testing purposes. */
+ * (will) include Amazon S3 and a simple local store for testing purposes.
+ * Operations may be performed asynchronously. */
-struct _BlueSkyStore {
+struct BlueSkyStore {
const BlueSkyStoreImplementation *impl;
gpointer handle;
+
+ GMutex *lock;
+ GCond *cond_idle;
+ int pending; /* Count of operations not yet complete. */
+
+ struct bluesky_stats *stats_get, *stats_put;
};
GHashTable *store_implementations;
+/* Thread pool for calling notifier functions when an operation completes.
+ * These are called in a separate thread for locking reasons: we want to call
+ * the notifiers without the lock on the async object held, but completion
+ * occurs when the lock is held--so we need some way to defer the call. This
+ * isn't really optimal from a cache-locality standpoint. */
+static GThreadPool *notifier_thread_pool;
+
void bluesky_store_register(const BlueSkyStoreImplementation *impl,
const gchar *name)
{
{
const BlueSkyStoreImplementation *impl;
- impl = g_hash_table_lookup(store_implementations, type);
- if (impl == NULL)
+ gchar *scheme, *path;
+ scheme = g_strdup(type);
+ path = strchr(scheme, ':');
+ if (path != NULL) {
+ *path = '\0';
+ path++;
+ }
+
+ impl = g_hash_table_lookup(store_implementations, scheme);
+ if (impl == NULL) {
+ g_free(scheme);
return NULL;
+ }
- gpointer handle = impl->create();
- if (handle == NULL)
+ gpointer handle = impl->create(path);
+ if (handle == NULL) {
+ g_free(scheme);
return NULL;
+ }
BlueSkyStore *store = g_new(BlueSkyStore, 1);
store->impl = impl;
store->handle = handle;
+ store->lock = g_mutex_new();
+ store->cond_idle = g_cond_new();
+ store->pending = 0;
+ store->stats_get = bluesky_stats_new(g_strdup_printf("Store[%s]: GETS",
+ type));
+ store->stats_put = bluesky_stats_new(g_strdup_printf("Store[%s]: PUTS",
+ type));
+ g_free(scheme);
return store;
}
g_free(store);
}
-BlueSkyRCStr *bluesky_store_get(BlueSkyStore *store, const gchar *key)
+char *bluesky_store_lookup_last(BlueSkyStore *store, const char *prefix)
{
- return store->impl->get(store->handle, key);
+ return store->impl->lookup_last(store->handle, prefix);
}
-void bluesky_store_put(BlueSkyStore *store,
- const gchar *key, BlueSkyRCStr *val)
+BlueSkyStoreAsync *bluesky_store_async_new(BlueSkyStore *store)
{
- store->impl->put(store->handle, key, val);
+ BlueSkyStoreAsync *async;
+
+ async = g_new(BlueSkyStoreAsync, 1);
+ async->store = store;
+ async->lock = g_mutex_new();
+ async->completion_cond = g_cond_new();
+ async->refcount = 1;
+ async->status = ASYNC_NEW;
+ async->op = STORE_OP_NONE;
+ async->key = NULL;
+ async->data = NULL;
+ async->start = async->len = 0;
+ async->range_done = FALSE;
+ async->result = -1;
+ async->notifiers = NULL;
+ async->notifier_count = 0;
+ async->barrier = NULL;
+ async->store_private = NULL;
+ async->profile = NULL;
+
+ return async;
}
-/* Create and return a new reference-counted string. The reference count is
- * initially one. The newly-returned string takes ownership of the memory
- * pointed at by data, and will call g_free on it when the reference count
- * drops to zero. */
-BlueSkyRCStr *bluesky_string_new(gpointer data, gsize len)
+gpointer bluesky_store_async_get_handle(BlueSkyStoreAsync *async)
{
- BlueSkyRCStr *string = g_new(BlueSkyRCStr, 1);
- string->data = data;
- string->len = len;
- g_atomic_int_set(&string->refcount, 1);
- return string;
+ return async->store->handle;
}
-void bluesky_string_ref(BlueSkyRCStr *string)
+void bluesky_store_async_ref(BlueSkyStoreAsync *async)
{
- if (string == NULL)
+ if (async == NULL)
return;
- g_atomic_int_inc(&string->refcount);
+ g_return_if_fail(g_atomic_int_get(&async->refcount) > 0);
+
+ g_atomic_int_inc(&async->refcount);
}
-void bluesky_string_unref(BlueSkyRCStr *string)
+void bluesky_store_async_unref(BlueSkyStoreAsync *async)
{
- if (string == NULL)
+ if (async == NULL)
return;
- if (g_atomic_int_dec_and_test(&string->refcount)) {
- g_free(string->data);
- g_free(string);
+ if (g_atomic_int_dec_and_test(&async->refcount)) {
+ async->store->impl->cleanup(async->store->handle, async);
+ g_mutex_free(async->lock);
+ g_cond_free(async->completion_cond);
+ g_free(async->key);
+ bluesky_string_unref(async->data);
+ g_free(async);
}
}
-/* Duplicate and return a new reference-counted string, containing a copy of
- * the original data, with a reference count of 1. As an optimization, if the
- * passed-in string already has a reference count of 1, the original is
- * returned. Can be used to make a mutable copy of a shared string. For this
- * to truly be safe, it is probably needed that there be some type of lock
- * protecting access to the string. */
-BlueSkyRCStr *bluesky_string_dup(BlueSkyRCStr *string)
+/* Block until the given operation has completed. */
+void bluesky_store_async_wait(BlueSkyStoreAsync *async)
{
- if (string == NULL)
- return NULL;
+ g_return_if_fail(async != NULL);
+ g_mutex_lock(async->lock);
- if (g_atomic_int_dec_and_test(&string->refcount)) {
- /* There are no other shared copies, so return this one. */
- g_atomic_int_inc(&string->refcount);
- return string;
+ if (async->status == ASYNC_NEW) {
+ g_error("bluesky_store_async_wait on a new async object!\n");
+ g_mutex_unlock(async->lock);
+ return;
+ }
+
+ while (async->status != ASYNC_COMPLETE
+ || g_atomic_int_get(&async->notifier_count) > 0) {
+ g_cond_wait(async->completion_cond, async->lock);
+ }
+
+ g_mutex_unlock(async->lock);
+}
+
+/* Add a notifier function to be called when the operation completes. */
+void bluesky_store_async_add_notifier(BlueSkyStoreAsync *async,
+ GFunc func, gpointer user_data)
+{
+ struct BlueSkyNotifierList *nl = g_new(struct BlueSkyNotifierList, 1);
+ g_mutex_lock(async->lock);
+ nl->next = async->notifiers;
+ nl->func = func;
+ nl->async = async; bluesky_store_async_ref(async);
+ nl->user_data = user_data;
+ g_atomic_int_inc(&async->notifier_count);
+ if (async->status == ASYNC_COMPLETE) {
+ g_thread_pool_push(notifier_thread_pool, nl, NULL);
} else {
- return bluesky_string_new(g_memdup(string->data, string->len),
- string->len);
+ async->notifiers = nl;
+ }
+ g_mutex_unlock(async->lock);
+}
+
+static void op_complete(gpointer a, gpointer b)
+{
+ BlueSkyStoreAsync *barrier = (BlueSkyStoreAsync *)b;
+
+ bluesky_store_async_ref(barrier);
+ g_mutex_lock(barrier->lock);
+ barrier->store_private
+ = GINT_TO_POINTER(GPOINTER_TO_INT(barrier->store_private) - 1);
+ if (GPOINTER_TO_INT(barrier->store_private) == 0
+ && barrier->status != ASYNC_NEW) {
+ bluesky_store_async_mark_complete(barrier);
+ }
+ g_mutex_unlock(barrier->lock);
+ bluesky_store_async_unref(barrier);
+}
+
+/* Mark an asynchronous operation as complete. This should only be called by
+ * the store implementations. The lock should be held when calling this
+ * function. Any notifier functions will be called, but in a separate thread
+ * and without the lock held. */
+void bluesky_store_async_mark_complete(BlueSkyStoreAsync *async)
+{
+ g_return_if_fail(async->status != ASYNC_COMPLETE);
+
+ bluesky_time_hires elapsed = bluesky_now_hires() - async->start_time;
+ bluesky_time_hires latency = bluesky_now_hires() - async->exec_time;
+
+ if (async->op != STORE_OP_BARRIER) {
+ g_mutex_lock(async->store->lock);
+ async->store->pending--;
+ if (async->store->pending == 0)
+ g_cond_broadcast(async->store->cond_idle);
+ g_mutex_unlock(async->store->lock);
+ }
+
+ /* If the request was a range request but the backend read the entire
+ * object, select out the appropriate bytes. */
+ if (async->op == STORE_OP_GET
+ && !async->range_done
+ && async->result == 0
+ && async->data != NULL) {
+ if (async->start != 0 || async->len != 0) {
+ /* If the caller requesteda read outside the object, return an
+ * error. */
+ if (async->start + async->len > async->data->len) {
+ g_warning("Range request outside object boundaries!\n");
+ async->result = -1;
+ } else {
+ if (async->len == 0)
+ async->len = async->data->len - async->start;
+ BlueSkyRCStr *newstr = bluesky_string_new(g_memdup(&async->data->data[async->start], async->len), async->len);
+ bluesky_string_unref(async->data);
+ async->data = newstr;
+ async->range_done = TRUE;
+ }
+ }
+ }
+
+ async->status = ASYNC_COMPLETE;
+ g_cond_broadcast(async->completion_cond);
+
+ if (async->barrier != NULL && async->notifiers == NULL)
+ op_complete(async, async->barrier);
+
+ while (async->notifiers != NULL) {
+ struct BlueSkyNotifierList *nl = async->notifiers;
+ async->notifiers = nl->next;
+ g_thread_pool_push(notifier_thread_pool, nl, NULL);
+ }
+
+ if (async->profile) {
+ bluesky_profile_add_event(
+ async->profile,
+ g_strdup_printf("%s for %s complete",
+ async->op == STORE_OP_GET ? "GET"
+ : async->op == STORE_OP_PUT ? "PUT"
+ : async->op == STORE_OP_DELETE ? "DELETE"
+ : async->op == STORE_OP_BARRIER ? "BARRIER" : "???",
+ async->key)
+ );
+ }
+
+ if (bluesky_verbose) {
+ g_log("bluesky/store", G_LOG_LEVEL_DEBUG,
+ "[%p] complete: elapsed = %"PRIi64" ns, latency = %"PRIi64" ns",
+ async, elapsed, latency);
+ }
+
+ if (async->data) {
+ if (async->op == STORE_OP_GET) {
+ bluesky_stats_add(async->store->stats_get, async->data->len);
+ } else if (async->op == STORE_OP_PUT) {
+ bluesky_stats_add(async->store->stats_put, async->data->len);
+ }
+ }
+}
+
+void bluesky_store_async_submit(BlueSkyStoreAsync *async)
+{
+ BlueSkyStore *store = async->store;
+
+ async->start_time = bluesky_now_hires();
+
+ // Backends should fill this in with a better estimate of the actual time
+ // processing was started, if there could be a delay from submission time.
+ async->exec_time = bluesky_now_hires();
+
+ if (async->profile) {
+ bluesky_profile_add_event(
+ async->profile,
+ g_strdup_printf("Start %s for %s",
+ async->op == STORE_OP_GET ? "GET"
+ : async->op == STORE_OP_PUT ? "PUT"
+ : async->op == STORE_OP_DELETE ? "DELETE"
+ : async->op == STORE_OP_BARRIER ? "BARRIER" : "???",
+ async->key)
+ );
+ }
+
+ if (bluesky_verbose) {
+ g_log("bluesky/store", G_LOG_LEVEL_DEBUG, "[%p] submit: %s %s",
+ async,
+ async->op == STORE_OP_GET ? "GET"
+ : async->op == STORE_OP_PUT ? "PUT"
+ : async->op == STORE_OP_DELETE ? "DELETE"
+ : async->op == STORE_OP_BARRIER ? "BARRIER" : "???",
+ async->key);
+ }
+
+ /* Barriers are handled specially, and not handed down the storage
+ * implementation layer. */
+ if (async->op == STORE_OP_BARRIER) {
+ async->status = ASYNC_RUNNING;
+ if (GPOINTER_TO_INT(async->store_private) == 0)
+ bluesky_store_async_mark_complete(async);
+ return;
+ }
+
+ g_mutex_lock(async->store->lock);
+ async->store->pending++;
+ g_mutex_unlock(async->store->lock);
+
+ store->impl->submit(store->handle, async);
+
+ if (bluesky_options.synchronous_stores)
+ bluesky_store_async_wait(async);
+}
+
+/* Add the given operation to the barrier. The barrier will not complete until
+ * all operations added to it have completed. */
+void bluesky_store_add_barrier(BlueSkyStoreAsync *barrier,
+ BlueSkyStoreAsync *async)
+{
+ g_return_if_fail(barrier->op == STORE_OP_BARRIER);
+
+ g_mutex_lock(barrier->lock);
+ barrier->store_private
+ = GINT_TO_POINTER(GPOINTER_TO_INT(barrier->store_private) + 1);
+ g_mutex_unlock(barrier->lock);
+
+ g_mutex_lock(async->lock);
+ if (async->barrier == NULL && async->status != ASYNC_COMPLETE) {
+ async->barrier = barrier;
+ g_mutex_unlock(async->lock);
+ } else {
+ if (async->barrier != NULL)
+ g_warning("Adding async to more than one barrier!\n");
+ g_mutex_unlock(async->lock);
+ bluesky_store_async_add_notifier(async, op_complete, barrier);
+ }
+}
+
+static void notifier_task(gpointer n, gpointer s)
+{
+ struct BlueSkyNotifierList *notifier = (struct BlueSkyNotifierList *)n;
+
+ notifier->func(notifier->async, notifier->user_data);
+ if (g_atomic_int_dec_and_test(¬ifier->async->notifier_count)) {
+ g_mutex_lock(notifier->async->lock);
+ if (notifier->async->barrier != NULL)
+ op_complete(notifier->async, notifier->async->barrier);
+ g_cond_broadcast(notifier->async->completion_cond);
+ g_mutex_unlock(notifier->async->lock);
+ }
+ bluesky_store_async_unref(notifier->async);
+ g_free(notifier);
+}
+
+void bluesky_store_sync(BlueSkyStore *store)
+{
+ g_mutex_lock(store->lock);
+ if (bluesky_verbose) {
+ g_log("bluesky/store", G_LOG_LEVEL_DEBUG,
+ "Waiting for pending store operations to complete...");
+ }
+ while (store->pending > 0) {
+ g_cond_wait(store->cond_idle, store->lock);
+ }
+ g_mutex_unlock(store->lock);
+ if (bluesky_verbose) {
+ g_log("bluesky/store", G_LOG_LEVEL_DEBUG, "Operations are complete.");
}
}
+/* Convenience wrappers that perform a single operation synchronously. */
+BlueSkyRCStr *bluesky_store_get(BlueSkyStore *store, const gchar *key)
+{
+ BlueSkyStoreAsync *async = bluesky_store_async_new(store);
+ async->op = STORE_OP_GET;
+ async->key = g_strdup(key);
+ bluesky_store_async_submit(async);
+
+ bluesky_store_async_wait(async);
+
+ BlueSkyRCStr *data = async->data;
+ bluesky_string_ref(data);
+ bluesky_store_async_unref(async);
+ return data;
+}
+
+void bluesky_store_put(BlueSkyStore *store,
+ const gchar *key, BlueSkyRCStr *val)
+{
+ BlueSkyStoreAsync *async = bluesky_store_async_new(store);
+ async->op = STORE_OP_PUT;
+ async->key = g_strdup(key);
+ bluesky_string_ref(val);
+ async->data = val;
+ bluesky_store_async_submit(async);
+
+ bluesky_store_async_wait(async);
+ bluesky_store_async_unref(async);
+}
+
/* Simple in-memory data store for test purposes. */
typedef struct {
GMutex *lock;
GHashTable *store;
} MemStore;
-static gpointer memstore_create()
+static gpointer memstore_create(const gchar *path)
{
MemStore *store = g_new(MemStore, 1);
store->lock = g_mutex_new();
g_hash_table_insert(store->store, g_strdup(key), val);
}
+static void memstore_submit(gpointer s, BlueSkyStoreAsync *async)
+{
+ g_return_if_fail(async->status == ASYNC_NEW);
+ g_return_if_fail(async->op != STORE_OP_NONE);
+
+ switch (async->op) {
+ case STORE_OP_GET:
+ async->data = memstore_get(s, async->key);
+ break;
+
+ case STORE_OP_PUT:
+ memstore_put(s, async->key, async->data);
+ break;
+
+ default:
+ g_warning("Uknown operation type for MemStore: %d\n", async->op);
+ return;
+ }
+
+ bluesky_store_async_mark_complete(async);
+}
+
+static void memstore_cleanup(gpointer store, BlueSkyStoreAsync *async)
+{
+}
+
static BlueSkyStoreImplementation memstore_impl = {
.create = memstore_create,
.destroy = memstore_destroy,
- .get = memstore_get,
- .put = memstore_put,
+ .submit = memstore_submit,
+ .cleanup = memstore_cleanup,
};
/* Store implementation which writes data as files to disk. */
-static gpointer filestore_create()
+static gpointer filestore_create(const gchar *path)
{
return GINT_TO_POINTER(1);
}
{
}
-static BlueSkyRCStr *filestore_get(gpointer s, const gchar *key)
+static BlueSkyRCStr *filestore_get(const gchar *key)
{
gchar *contents = NULL;
gsize length;
return bluesky_string_new(contents, length);
}
-static void filestore_put(gpointer s, const gchar *key, BlueSkyRCStr *val)
+static void filestore_put(const gchar *key, BlueSkyRCStr *val)
{
g_file_set_contents(key, val->data, val->len, NULL);
}
+static void filestore_submit(gpointer s, BlueSkyStoreAsync *async)
+{
+ g_return_if_fail(async->status == ASYNC_NEW);
+ g_return_if_fail(async->op != STORE_OP_NONE);
+
+ switch (async->op) {
+ case STORE_OP_GET:
+ async->data = filestore_get(async->key);
+ async->result = 0;
+ break;
+
+ case STORE_OP_PUT:
+ filestore_put(async->key, async->data);
+ async->result = 0;
+ break;
+
+ default:
+ g_warning("Uknown operation type for FileStore: %d\n", async->op);
+ return;
+ }
+
+ bluesky_store_async_mark_complete(async);
+}
+
+static void filestore_cleanup(gpointer store, BlueSkyStoreAsync *async)
+{
+}
+
+static char *filestore_lookup_last(gpointer store, const char *prefix)
+{
+ char *last = NULL;
+ GDir *dir = g_dir_open(".", 0, NULL);
+ if (dir == NULL) {
+ g_warning("Unable to open directory for listing");
+ return NULL;
+ }
+
+ const gchar *file;
+ while ((file = g_dir_read_name(dir)) != NULL) {
+ if (strncmp(file, prefix, strlen(prefix)) == 0) {
+ if (last == NULL || strcmp(file, last) > 0) {
+ g_free(last);
+ last = g_strdup(file);
+ }
+ }
+ }
+ g_dir_close(dir);
+
+ return last;
+}
+
static BlueSkyStoreImplementation filestore_impl = {
.create = filestore_create,
.destroy = filestore_destroy,
- .get = filestore_get,
- .put = filestore_put,
+ .submit = filestore_submit,
+ .cleanup = filestore_cleanup,
+ .lookup_last = filestore_lookup_last,
+};
+
+/* A store implementation which simply discards all data, for testing. */
+static gpointer nullstore_create(const gchar *path)
+{
+ return (gpointer)nullstore_create;
+}
+
+static void nullstore_destroy(gpointer store)
+{
+}
+
+static void nullstore_submit(gpointer s, BlueSkyStoreAsync *async)
+{
+ bluesky_store_async_mark_complete(async);
+}
+
+static void nullstore_cleanup(gpointer store, BlueSkyStoreAsync *async)
+{
+}
+
+static BlueSkyStoreImplementation nullstore_impl = {
+ .create = nullstore_create,
+ .destroy = nullstore_destroy,
+ .submit = nullstore_submit,
+ .cleanup = nullstore_cleanup,
};
void bluesky_store_init()
{
store_implementations = g_hash_table_new(g_str_hash, g_str_equal);
+ notifier_thread_pool = g_thread_pool_new(notifier_task, NULL,
+ bluesky_max_threads, FALSE, NULL);
bluesky_store_register(&memstore_impl, "mem");
bluesky_store_register(&filestore_impl, "file");
+ bluesky_store_register(&nullstore_impl, "null");
}
projects / bluesky.git / blobdiff