#include <errno.h>
#include <signal.h>
#include <assert.h>
+#include <fcntl.h>
#define STRINGIFY2(x) #x
#define STRINGIFY(x) STRINGIFY2(x)
int fd[2];
};
static struct pipe *pipes;
+static int backoff_fd = -1;
static void __attribute__((noreturn)) fail(const char *filename,
unsigned int line,
OP_TDB_TRAVERSE_START,
OP_TDB_TRAVERSE_END,
OP_TDB_TRAVERSE,
+ OP_TDB_TRAVERSE_END_EARLY,
OP_TDB_FIRSTKEY,
OP_TDB_NEXTKEY,
OP_TDB_FETCH,
};
struct op {
- unsigned int serial;
- enum op_type op;
+ unsigned int seqnum;
+ enum op_type type;
TDB_DATA key;
TDB_DATA data;
int ret;
union {
int flag; /* open and store */
- struct traverse *trav; /* traverse start */
struct { /* append */
TDB_DATA pre;
TDB_DATA post;
} append;
- unsigned int transaction_end; /* transaction start */
+ /* transaction/traverse start/chainlock */
+ unsigned int group_len;
};
};
+struct op_desc {
+ unsigned int file;
+ unsigned int op_num;
+};
+
static unsigned char hex_char(const char *filename, unsigned int line, char c)
{
c = toupper(c);
}
static void add_op(const char *filename, struct op **op, unsigned int i,
- unsigned int serial, enum op_type type)
+ unsigned int seqnum, enum op_type type)
{
struct op *new;
*op = talloc_realloc(NULL, *op, struct op, i+1);
new = (*op) + i;
- new->op = type;
- new->serial = serial;
+ new->type = type;
+ new->seqnum = seqnum;
new->ret = 0;
new->group_start = 0;
}
fail(filename, op_num+1, "Expected just a key");
op[op_num].key = make_tdb_data(op, filename, op_num+1, words[2]);
- if (op[op_num].op != OP_TDB_TRAVERSE)
- total_keys++;
+ total_keys++;
}
static void op_add_key_ret(const char *filename,
total_keys++;
}
-/* <serial> tdb_store <rec> <rec> <flag> = <ret> */
+/* We don't record the keys or data for a traverse, as we don't use them. */
+static void op_add_traverse(const char *filename,
+ struct op op[], unsigned int op_num, char *words[])
+{
+ if (!words[2] || !words[3] || !words[4] || words[5]
+ || !streq(words[3], "="))
+ fail(filename, op_num+1, "Expected <key> = <data>");
+ op[op_num].key = tdb_null;
+}
+
+/* Full traverse info is useful for debugging, but changing it to
+ * "traversefn" without the data makes the traces *much* smaller! */
+static void op_add_traversefn(const char *filename,
+ struct op op[], unsigned int op_num, char *words[])
+{
+ if (words[2])
+ fail(filename, op_num+1, "Expected no values");
+ op[op_num].key = tdb_null;
+}
+
+/* <seqnum> tdb_store <rec> <rec> <flag> = <ret> */
static void op_add_store(const char *filename,
struct op op[], unsigned int op_num, char *words[])
{
total_keys++;
}
-/* <serial> tdb_append <rec> <rec> = <rec> */
+/* <seqnum> tdb_append <rec> <rec> = <rec> */
static void op_add_append(const char *filename,
struct op op[], unsigned int op_num, char *words[])
{
total_keys++;
}
-/* <serial> tdb_get_seqnum = <ret> */
+/* <seqnum> tdb_get_seqnum = <ret> */
static void op_add_seqnum(const char *filename,
struct op op[], unsigned int op_num, char *words[])
{
op[op_num].ret = atoi(words[3]);
}
-static void op_add_traverse(const char *filename,
- struct op op[], unsigned int op_num, char *words[])
+static void op_add_traverse_start(const char *filename,
+ struct op op[],
+ unsigned int op_num, char *words[])
{
if (words[2])
fail(filename, op_num+1, "Expect no arguments");
op[op_num].key = tdb_null;
- op[op_num].trav = NULL;
+ op[op_num].group_len = 0;
}
static void op_add_transaction(const char *filename, struct op op[],
fail(filename, op_num+1, "Expect no arguments");
op[op_num].key = tdb_null;
- op[op_num].transaction_end = 0;
+ op[op_num].group_len = 0;
+}
+
+static void op_add_chainlock(const char *filename,
+ struct op op[], unsigned int op_num, char *words[])
+{
+ if (words[2] == NULL || words[3])
+ fail(filename, op_num+1, "Expected just a key");
+
+ /* A chainlock key isn't a key in the normal sense; it doesn't
+ * have to be in the db at all. Also, we don't want to hash this op. */
+ op[op_num].data = make_tdb_data(op, filename, op_num+1, words[2]);
+ op[op_num].key = tdb_null;
+ op[op_num].group_len = 0;
+}
+
+static void op_add_chainlock_ret(const char *filename,
+ struct op op[], unsigned int op_num,
+ char *words[])
+{
+ if (!words[2] || !words[3] || !words[4] || words[5]
+ || !streq(words[3], "="))
+ fail(filename, op_num+1, "Expected <key> = <ret>");
+ op[op_num].ret = atoi(words[4]);
+ op[op_num].data = make_tdb_data(op, filename, op_num+1, words[2]);
+ op[op_num].key = tdb_null;
+ op[op_num].group_len = 0;
+ total_keys++;
+}
+
+static int op_find_start(struct op op[], unsigned int op_num, enum op_type type)
+{
+ unsigned int i;
+
+ for (i = op_num-1; i > 0; i--) {
+ if (op[i].type == type && !op[i].group_len)
+ return i;
+ }
+ return 0;
}
static void op_analyze_transaction(const char *filename,
struct op op[], unsigned int op_num,
char *words[])
{
- int i, start;
+ unsigned int start, i;
op[op_num].key = tdb_null;
if (words[2])
fail(filename, op_num+1, "Expect no arguments");
- for (i = op_num-1; i >= 0; i--) {
- if (op[i].op == OP_TDB_TRANSACTION_START &&
- !op[i].transaction_end)
- break;
- }
-
- if (i < 0)
+ start = op_find_start(op, op_num, OP_TDB_TRANSACTION_START);
+ if (!start)
fail(filename, op_num+1, "no transaction start found");
- start = i;
- op[start].transaction_end = op_num;
+ op[start].group_len = op_num - start;
/* This rolls in nested transactions. I think that's right. */
- for (i++; i <= op_num; i++)
+ for (i = start; i <= op_num; i++)
op[i].group_start = start;
}
-struct traverse_hash {
- TDB_DATA key;
- unsigned int index;
-};
-
-/* A traverse is a hash of keys, each one associated with ops. */
-struct traverse {
- /* How many traversal callouts should I do? */
- unsigned int num;
+/* We treat chainlocks a lot like transactions, even though that's overkill */
+static void op_analyze_chainlock(const char *filename,
+ struct op op[], unsigned int op_num,
+ char *words[])
+{
+ unsigned int i, start;
- /* Where is traversal end op? */
- unsigned int end;
+ if (words[2] == NULL || words[3])
+ fail(filename, op_num+1, "Expected just a key");
- /* For trivial traversals. */
- struct traverse_hash *hash;
-};
+ op[op_num].data = make_tdb_data(op, filename, op_num+1, words[2]);
+ op[op_num].key = tdb_null;
+ total_keys++;
-/* A trivial traversal is one which doesn't terminate early and only
- * plays with its own record. We can reliably replay these even if
- * traverse order changes. */
-static bool is_trivial_traverse(struct op op[], unsigned int end)
-{
-#if 0
- unsigned int i;
- TDB_DATA cur = tdb_null;
+ start = op_find_start(op, op_num, OP_TDB_CHAINLOCK);
+ if (!start)
+ start = op_find_start(op, op_num, OP_TDB_CHAINLOCK_READ);
+ if (!start)
+ fail(filename, op_num+1, "no initial chainlock found");
- if (op[end].ret != 0)
- return false;
+ /* FIXME: We'd have to do something clever to make this work
+ * vs. deadlock. */
+ if (!key_eq(op[start].data, op[op_num].data))
+ fail(filename, op_num+1, "nested chainlock calls?");
- for (i = 0; i < end; i++) {
- if (!op[i].key.dptr)
- continue;
- if (op[i].op == OP_TDB_TRAVERSE)
- cur = op[i].key;
- if (!key_eq(cur, op[i].key))
- return false;
- }
- return true;
-#endif
- /* With multiple things happening at once, no traverse is trivial. */
- return false;
+ op[start].group_len = op_num - start;
+ for (i = start; i <= op_num; i++)
+ op[i].group_start = start;
}
static void op_analyze_traverse(const char *filename,
char *words[])
{
int i, start;
- struct traverse *trav = talloc(op, struct traverse);
op[op_num].key = tdb_null;
} else
op[op_num].ret = 0;
- trav->num = 0;
- trav->end = op_num;
- for (i = op_num-1; i >= 0; i--) {
- if (op[i].op == OP_TDB_TRAVERSE)
- trav->num++;
- if (op[i].op != OP_TDB_TRAVERSE_READ_START
- && op[i].op != OP_TDB_TRAVERSE_START)
- continue;
- if (op[i].trav)
- continue;
- break;
- }
-
- if (i < 0)
+ start = op_find_start(op, op_num, OP_TDB_TRAVERSE_START);
+ if (!start)
+ start = op_find_start(op, op_num, OP_TDB_TRAVERSE_READ_START);
+ if (!start)
fail(filename, op_num+1, "no traversal start found");
- start = i;
- op[start].trav = trav;
+ op[start].group_len = op_num - start;
+ /* Don't roll in nested traverse/chainlock */
for (i = start; i <= op_num; i++)
- op[i].group_start = start;
-
- if (is_trivial_traverse(op+i, op_num-i)) {
- /* Fill in a plentiful hash table. */
- op[start].trav->hash = talloc_zero_array(op[i].trav,
- struct traverse_hash,
- trav->num * 2);
- for (i = start; i < op_num; i++) {
- unsigned int h;
- if (op[i].op != OP_TDB_TRAVERSE)
- continue;
- h = hash_key(&op[i].key) % (trav->num * 2);
- while (trav->hash[h].index)
- h = (h + 1) % (trav->num * 2);
- trav->hash[h].index = i+1;
- trav->hash[h].key = op[i].key;
- }
- } else
- trav->hash = NULL;
+ if (!op[i].group_start)
+ op[i].group_start = start;
}
/* Keep -Wmissing-declarations happy: */
/* We can have more than one */
struct list_node pre_list;
struct list_node post_list;
- unsigned int needs_file;
- unsigned int needs_opnum;
- unsigned int satisfies_file;
- unsigned int satisfies_opnum;
+ struct op_desc needs;
+ struct op_desc prereq;
};
static void check_deps(const char *filename, struct op op[], unsigned int num)
#endif
}
-static void dump_pre(char *filename[], unsigned int file,
- struct op op[], unsigned int i)
+static void dump_pre(char *filename[], struct op *op[],
+ unsigned int file, unsigned int i)
{
struct depend *dep;
- printf("%s:%u still waiting for:\n", filename[file], i+1);
- list_for_each(&op[i].pre, dep, pre_list)
- printf(" %s:%u\n",
- filename[dep->satisfies_file], dep->satisfies_opnum+1);
- check_deps(filename[file], op, i);
+ printf("%s:%u (%u) still waiting for:\n", filename[file], i+1,
+ op[file][i].seqnum);
+ list_for_each(&op[file][i].pre, dep, pre_list)
+ printf(" %s:%u (%u)\n",
+ filename[dep->prereq.file], dep->prereq.op_num+1,
+ op[dep->prereq.file][dep->prereq.op_num].seqnum);
+ check_deps(filename[file], op[file], i);
}
/* We simply read/write pointers, since we all are children. */
-static void do_pre(char *filename[], unsigned int file, int pre_fd,
- struct op op[], unsigned int i)
+static bool do_pre(struct tdb_context *tdb,
+ char *filename[], struct op *op[],
+ unsigned int file, int pre_fd, unsigned int i,
+ bool backoff)
{
- while (!list_empty(&op[i].pre)) {
+ while (!list_empty(&op[file][i].pre)) {
struct depend *dep;
#if DEBUG_DEPS
printf("%s:%u:waiting for pre\n", filename[file], i+1);
fflush(stdout);
#endif
- alarm(10);
+ if (backoff)
+ alarm(2);
+ else
+ alarm(10);
while (read(pre_fd, &dep, sizeof(dep)) != sizeof(dep)) {
if (errno == EINTR) {
- dump_pre(filename, file, op, i);
+ if (backoff) {
+ struct op_desc desc = { file,i };
+ warnx("%s:%u:avoiding deadlock",
+ filename[file], i+1);
+ if (write(backoff_fd, &desc,
+ sizeof(desc)) != sizeof(desc))
+ err(1, "writing backoff_fd");
+ return false;
+ }
+ dump_pre(filename, op, file, i);
exit(1);
} else
errx(1, "Reading from pipe");
#if DEBUG_DEPS
printf("%s:%u:got pre %u from %s:%u\n", filename[file], i+1,
- dep->needs_op, dep->satisfies_file, dep->satisfies_op+1);
+ dep->needs.op_num+1, filename[dep->prereq.file],
+ dep->prereq.op_num+1);
fflush(stdout);
#endif
/* This could be any op, not just this one. */
talloc_free(dep);
}
+ return true;
}
-static void do_post(char *filename[], unsigned int file,
- const struct op op[], unsigned int i)
+static void do_post(char *filename[], struct op *op[],
+ unsigned int file, unsigned int i)
{
struct depend *dep;
- list_for_each(&op[i].post, dep, post_list) {
+ list_for_each(&op[file][i].post, dep, post_list) {
#if DEBUG_DEPS
printf("%s:%u:sending to file %s:%u\n", filename[file], i+1,
- filename[dep->needs_file], dep->needs_opnum+1);
+ filename[dep->needs.file], dep->needs.op_num+1);
#endif
- if (write(pipes[dep->needs_file].fd[1], &dep, sizeof(dep))
+ if (write(pipes[dep->needs.file].fd[1], &dep, sizeof(dep))
!= sizeof(dep))
err(1, "%s:%u failed to tell file %s",
- filename[file], i+1, filename[dep->needs_file]);
+ filename[file], i+1, filename[dep->needs.file]);
}
}
static unsigned run_ops(struct tdb_context *tdb,
int pre_fd,
char *filename[],
+ struct op *op[],
unsigned int file,
- struct op op[],
- unsigned int start, unsigned int stop);
+ unsigned int start, unsigned int stop,
+ bool backoff);
struct traverse_info {
- struct op *op;
+ struct op **op;
char **filename;
unsigned file;
int pre_fd;
unsigned int i;
};
-/* Trivial case: do whatever they did for this key. */
-static int trivial_traverse(struct tdb_context *tdb,
- TDB_DATA key, TDB_DATA data,
- void *_tinfo)
-{
- struct traverse_info *tinfo = _tinfo;
- struct traverse *trav = tinfo->op[tinfo->start].trav;
- unsigned int h = hash_key(&key) % (trav->num * 2);
-
- while (trav->hash[h].index) {
- if (key_eq(trav->hash[h].key, key)) {
- run_ops(tdb, tinfo->pre_fd, tinfo->filename,
- tinfo->file, tinfo->op, trav->hash[h].index,
- trav->end);
- tinfo->i++;
- return 0;
- }
- h = (h + 1) % (trav->num * 2);
- }
- fail(tinfo->filename[tinfo->file], tinfo->start + 1,
- "unexpected traverse key");
-}
-
/* More complex. Just do whatever's they did at the n'th entry. */
static int nontrivial_traverse(struct tdb_context *tdb,
TDB_DATA key, TDB_DATA data,
void *_tinfo)
{
struct traverse_info *tinfo = _tinfo;
- struct traverse *trav = tinfo->op[tinfo->start].trav;
+ unsigned int trav_len = tinfo->op[tinfo->file][tinfo->start].group_len;
+ bool avoid_deadlock = false;
- if (tinfo->i == trav->end) {
+ if (tinfo->i == tinfo->start + trav_len) {
/* This can happen if traverse expects to be empty. */
- if (tinfo->start + 1 == trav->end)
+ if (trav_len == 1)
return 1;
fail(tinfo->filename[tinfo->file], tinfo->start + 1,
"traverse did not terminate");
}
- if (tinfo->op[tinfo->i].op != OP_TDB_TRAVERSE)
+ if (tinfo->op[tinfo->file][tinfo->i].type != OP_TDB_TRAVERSE)
fail(tinfo->filename[tinfo->file], tinfo->start + 1,
"%s:%u:traverse terminated early");
+#if TRAVERSALS_TAKE_TRANSACTION_LOCK
+ avoid_deadlock = true;
+#endif
+
/* Run any normal ops. */
- tinfo->i = run_ops(tdb, tinfo->pre_fd, tinfo->filename, tinfo->file,
- tinfo->op, tinfo->i+1, trav->end);
+ tinfo->i = run_ops(tdb, tinfo->pre_fd, tinfo->filename, tinfo->op,
+ tinfo->file, tinfo->i+1, tinfo->start + trav_len,
+ avoid_deadlock);
- if (tinfo->i == trav->end)
+ /* We backed off, or we hit OP_TDB_TRAVERSE_END/EARLY. */
+ if (tinfo->op[tinfo->file][tinfo->i].type != OP_TDB_TRAVERSE)
return 1;
return 0;
unsigned int file,
int (*traversefn)(struct tdb_context *,
tdb_traverse_func, void *),
- struct op op[],
+ struct op *op[],
unsigned int start)
{
- struct traverse *trav = op[start].trav;
struct traverse_info tinfo = { op, filename, file, pre_fd,
start, start+1 };
- /* Trivial case. */
- if (trav->hash) {
- int ret = traversefn(tdb, trivial_traverse, &tinfo);
- if (ret != trav->num)
- fail(filename[file], start+1,
- "short traversal %i", ret);
- return trav->end;
- }
-
traversefn(tdb, nontrivial_traverse, &tinfo);
/* Traversing in wrong order can have strange effects: eg. if
* original traverse went A (delete A), B, we might do B
* (delete A). So if we have ops left over, we do it now. */
- while (tinfo.i != trav->end) {
- if (op[tinfo.i].op == OP_TDB_TRAVERSE)
+ while (tinfo.i != start + op[file][start].group_len) {
+ if (op[file][tinfo.i].type == OP_TDB_TRAVERSE
+ || op[file][tinfo.i].type == OP_TDB_TRAVERSE_END_EARLY)
tinfo.i++;
else
- tinfo.i = run_ops(tdb, pre_fd, filename, file, op,
- tinfo.i, trav->end);
+ tinfo.i = run_ops(tdb, pre_fd, filename, op, file,
+ tinfo.i,
+ start + op[file][start].group_len,
+ false);
}
- return trav->end;
+ return tinfo.i;
}
static void break_out(int sig)
unsigned run_ops(struct tdb_context *tdb,
int pre_fd,
char *filename[],
+ struct op *op[],
unsigned int file,
- struct op op[], unsigned int start, unsigned int stop)
+ unsigned int start, unsigned int stop,
+ bool backoff)
{
unsigned int i;
struct sigaction sa;
sigaction(SIGALRM, &sa, NULL);
for (i = start; i < stop; i++) {
- do_pre(filename, file, pre_fd, op, i);
+ if (!do_pre(tdb, filename, op, file, pre_fd, i, backoff))
+ return i;
- switch (op[i].op) {
+ switch (op[file][i].type) {
case OP_TDB_LOCKALL:
- try(tdb_lockall(tdb), op[i].ret);
+ try(tdb_lockall(tdb), op[file][i].ret);
break;
case OP_TDB_LOCKALL_MARK:
- try(tdb_lockall_mark(tdb), op[i].ret);
+ try(tdb_lockall_mark(tdb), op[file][i].ret);
break;
case OP_TDB_LOCKALL_UNMARK:
- try(tdb_lockall_unmark(tdb), op[i].ret);
+ try(tdb_lockall_unmark(tdb), op[file][i].ret);
break;
case OP_TDB_LOCKALL_NONBLOCK:
- unreliable(tdb_lockall_nonblock(tdb), op[i].ret,
+ unreliable(tdb_lockall_nonblock(tdb), op[file][i].ret,
tdb_lockall(tdb), tdb_unlockall(tdb));
break;
case OP_TDB_UNLOCKALL:
- try(tdb_unlockall(tdb), op[i].ret);
+ try(tdb_unlockall(tdb), op[file][i].ret);
break;
case OP_TDB_LOCKALL_READ:
- try(tdb_lockall_read(tdb), op[i].ret);
+ try(tdb_lockall_read(tdb), op[file][i].ret);
break;
case OP_TDB_LOCKALL_READ_NONBLOCK:
- unreliable(tdb_lockall_read_nonblock(tdb), op[i].ret,
+ unreliable(tdb_lockall_read_nonblock(tdb),
+ op[file][i].ret,
tdb_lockall_read(tdb),
tdb_unlockall_read(tdb));
break;
case OP_TDB_UNLOCKALL_READ:
- try(tdb_unlockall_read(tdb), op[i].ret);
+ try(tdb_unlockall_read(tdb), op[file][i].ret);
break;
case OP_TDB_CHAINLOCK:
- try(tdb_chainlock(tdb, op[i].key), op[i].ret);
+ try(tdb_chainlock(tdb, op[file][i].key),
+ op[file][i].ret);
break;
case OP_TDB_CHAINLOCK_NONBLOCK:
- unreliable(tdb_chainlock_nonblock(tdb, op[i].key),
- op[i].ret,
- tdb_chainlock(tdb, op[i].key),
- tdb_chainunlock(tdb, op[i].key));
+ unreliable(tdb_chainlock_nonblock(tdb, op[file][i].key),
+ op[file][i].ret,
+ tdb_chainlock(tdb, op[file][i].key),
+ tdb_chainunlock(tdb, op[file][i].key));
break;
case OP_TDB_CHAINLOCK_MARK:
- try(tdb_chainlock_mark(tdb, op[i].key), op[i].ret);
+ try(tdb_chainlock_mark(tdb, op[file][i].key),
+ op[file][i].ret);
break;
case OP_TDB_CHAINLOCK_UNMARK:
- try(tdb_chainlock_unmark(tdb, op[i].key), op[i].ret);
+ try(tdb_chainlock_unmark(tdb, op[file][i].key),
+ op[file][i].ret);
break;
case OP_TDB_CHAINUNLOCK:
- try(tdb_chainunlock(tdb, op[i].key), op[i].ret);
+ try(tdb_chainunlock(tdb, op[file][i].key),
+ op[file][i].ret);
break;
case OP_TDB_CHAINLOCK_READ:
- try(tdb_chainlock_read(tdb, op[i].key), op[i].ret);
+ try(tdb_chainlock_read(tdb, op[file][i].key),
+ op[file][i].ret);
break;
case OP_TDB_CHAINUNLOCK_READ:
- try(tdb_chainunlock_read(tdb, op[i].key), op[i].ret);
+ try(tdb_chainunlock_read(tdb, op[file][i].key),
+ op[file][i].ret);
break;
case OP_TDB_PARSE_RECORD:
- try(tdb_parse_record(tdb, op[i].key, get_len, NULL),
- op[i].ret);
+ try(tdb_parse_record(tdb, op[file][i].key, get_len,
+ NULL),
+ op[file][i].ret);
break;
case OP_TDB_EXISTS:
- try(tdb_exists(tdb, op[i].key), op[i].ret);
+ try(tdb_exists(tdb, op[file][i].key), op[file][i].ret);
break;
case OP_TDB_STORE:
- try(tdb_store(tdb, op[i].key, op[i].data, op[i].flag),
- op[i].ret);
+ try(tdb_store(tdb, op[file][i].key, op[file][i].data,
+ op[file][i].flag),
+ op[file][i].ret);
break;
case OP_TDB_APPEND:
- try(tdb_append(tdb, op[i].key, op[i].data), op[i].ret);
+ try(tdb_append(tdb, op[file][i].key, op[file][i].data),
+ op[file][i].ret);
break;
case OP_TDB_GET_SEQNUM:
- try(tdb_get_seqnum(tdb), op[i].ret);
+ try(tdb_get_seqnum(tdb), op[file][i].ret);
break;
case OP_TDB_WIPE_ALL:
- try(tdb_wipe_all(tdb), op[i].ret);
+ try(tdb_wipe_all(tdb), op[file][i].ret);
break;
case OP_TDB_TRANSACTION_START:
- try(tdb_transaction_start(tdb), op[i].ret);
+ try(tdb_transaction_start(tdb), op[file][i].ret);
break;
case OP_TDB_TRANSACTION_CANCEL:
- try(tdb_transaction_cancel(tdb), op[i].ret);
+ try(tdb_transaction_cancel(tdb), op[file][i].ret);
break;
case OP_TDB_TRANSACTION_COMMIT:
- try(tdb_transaction_commit(tdb), op[i].ret);
+ try(tdb_transaction_commit(tdb), op[file][i].ret);
break;
case OP_TDB_TRAVERSE_READ_START:
i = op_traverse(tdb, pre_fd, filename, file,
tdb_traverse, op, i);
break;
case OP_TDB_TRAVERSE:
+ case OP_TDB_TRAVERSE_END_EARLY:
/* Terminate: we're in a traverse, and we've
* done our ops. */
return i;
case OP_TDB_TRAVERSE_END:
- fail(filename[file], i+1, "unepxected end traverse");
+ fail(filename[file], i+1, "unexpected end traverse");
/* FIXME: These must be treated like traverse. */
case OP_TDB_FIRSTKEY:
- if (!key_eq(tdb_firstkey(tdb), op[i].data))
+ if (!key_eq(tdb_firstkey(tdb), op[file][i].data))
fail(filename[file], i+1, "bad firstkey");
break;
case OP_TDB_NEXTKEY:
- if (!key_eq(tdb_nextkey(tdb, op[i].key), op[i].data))
+ if (!key_eq(tdb_nextkey(tdb, op[file][i].key),
+ op[file][i].data))
fail(filename[file], i+1, "bad nextkey");
break;
case OP_TDB_FETCH: {
- TDB_DATA f = tdb_fetch(tdb, op[i].key);
- if (!key_eq(f, op[i].data))
+ TDB_DATA f = tdb_fetch(tdb, op[file][i].key);
+ if (!key_eq(f, op[file][i].data))
fail(filename[file], i+1, "bad fetch %u",
f.dsize);
break;
}
case OP_TDB_DELETE:
- try(tdb_delete(tdb, op[i].key), op[i].ret);
+ try(tdb_delete(tdb, op[file][i].key), op[file][i].ret);
break;
}
- do_post(filename, file, op, i);
+ do_post(filename, op, file, i);
}
return i;
}
+/* tdbtorture, in particular, can do a tdb_close with a transaction in
+ * progress. */
+static struct op *maybe_cancel_transaction(const char *filename,
+ struct op *op, unsigned int *num)
+{
+ unsigned int start = op_find_start(op, *num, OP_TDB_TRANSACTION_START);
+
+ if (start) {
+ char *words[] = { "<unknown>", "tdb_close", NULL };
+ add_op(filename, &op, *num, op[start].seqnum,
+ OP_TDB_TRANSACTION_CANCEL);
+ op_analyze_transaction(filename, op, *num, words);
+ (*num)++;
+ }
+ return op;
+}
+
static struct op *load_tracefile(const char *filename, unsigned int *num,
unsigned int *hashsize,
unsigned int *tdb_flags,
words = strsplit(lines, lines[i], " ", NULL);
if (!words[0] || !words[1])
- fail(filename, i+1, "Expected serial number and op");
+ fail(filename, i+1, "Expected seqnum number and op");
opt = find_keyword(words[1], strlen(words[1]));
if (!opt) {
"lines after tdb_close");
*num = i;
talloc_free(lines);
- return op;
+ return maybe_cancel_transaction(filename,
+ op, num);
}
fail(filename, i+1, "Unknown operation '%s'", words[1]);
}
filename, i);
talloc_free(lines);
*num = i - 1;
- return op;
+ return maybe_cancel_transaction(filename, op, num);
}
/* We remember all the keys we've ever seen, and who has them. */
-struct key_user {
- unsigned int file;
- unsigned int op_num;
-};
-
struct keyinfo {
TDB_DATA key;
unsigned int num_users;
- struct key_user *user;
+ struct op_desc *user;
};
static const TDB_DATA must_not_exist;
* not exist, otherwise the data it needs. */
static const TDB_DATA *needs(const struct op *op)
{
- switch (op->op) {
+ switch (op->type) {
/* FIXME: Pull forward deps, since we can deadlock */
case OP_TDB_CHAINLOCK:
case OP_TDB_CHAINLOCK_NONBLOCK:
return &must_exist;
default:
- errx(1, "Unexpected op %i", op->op);
+ errx(1, "Unexpected op type %i", op->type);
}
}
+static bool starts_transaction(const struct op *op)
+{
+ return op->type == OP_TDB_TRANSACTION_START;
+}
+
+static bool in_transaction(const struct op op[], unsigned int i)
+{
+ return op[i].group_start && starts_transaction(&op[op[i].group_start]);
+}
+
+static bool successful_transaction(const struct op *op)
+{
+ return starts_transaction(op)
+ && op[op->group_len].type == OP_TDB_TRANSACTION_COMMIT;
+}
+
+static bool starts_traverse(const struct op *op)
+{
+ return op->type == OP_TDB_TRAVERSE_START
+ || op->type == OP_TDB_TRAVERSE_READ_START;
+}
+
+static bool in_traverse(const struct op op[], unsigned int i)
+{
+ return op[i].group_start && starts_traverse(&op[op[i].group_start]);
+}
+
+static bool starts_chainlock(const struct op *op)
+{
+ return op->type == OP_TDB_CHAINLOCK_READ
+ || op->type == OP_TDB_CHAINLOCK;
+}
+
+static bool in_chainlock(const struct op op[], unsigned int i)
+{
+ return op[i].group_start && starts_chainlock(&op[op[i].group_start]);
+}
+
/* What's the data after this op? pre if nothing changed. */
-static const TDB_DATA *gives(const struct op *op, const TDB_DATA *pre)
+static const TDB_DATA *gives(const TDB_DATA *key, const TDB_DATA *pre,
+ const struct op *op)
{
+ if (starts_transaction(op) || starts_chainlock(op)) {
+ unsigned int i;
+
+ /* Cancelled transactions don't change anything. */
+ if (op[op->group_len].type == OP_TDB_TRANSACTION_CANCEL)
+ return pre;
+ assert(op[op->group_len].type == OP_TDB_TRANSACTION_COMMIT
+ || op[op->group_len].type == OP_TDB_CHAINUNLOCK_READ
+ || op[op->group_len].type == OP_TDB_CHAINUNLOCK);
+
+ for (i = 1; i < op->group_len; i++) {
+ /* This skips nested transactions, too */
+ if (key_eq(op[i].key, *key))
+ pre = gives(key, pre, &op[i]);
+ }
+ return pre;
+ }
+
/* Failed ops don't change state of db. */
if (op->ret < 0)
return pre;
- if (op->op == OP_TDB_DELETE || op->op == OP_TDB_WIPE_ALL)
+ if (op->type == OP_TDB_DELETE || op->type == OP_TDB_WIPE_ALL)
return &tdb_null;
- if (op->op == OP_TDB_APPEND)
+ if (op->type == OP_TDB_APPEND)
return &op->append.post;
- if (op->op == OP_TDB_STORE)
+ if (op->type == OP_TDB_STORE)
return &op->data;
return pre;
if (!op[i][j].key.dptr)
continue;
- /* We don't wait for traverse keys */
- /* FIXME: We should, for trivial traversals. */
- if (op[i][j].op == OP_TDB_TRAVERSE)
- continue;
-
h = hash_key(&op[i][j].key) % (total_keys * 2);
while (!key_eq(hash[h].key, op[i][j].key)) {
if (!hash[h].key.dptr) {
op[i][j].key.dptr = hash[h].key.dptr;
}
hash[h].user = talloc_realloc(hash, hash[h].user,
- struct key_user,
+ struct op_desc,
hash[h].num_users+1);
- hash[h].user[hash[h].num_users].op_num = j;
+
+ /* If it's in a transaction, it's the transaction which
+ * matters from an analysis POV. */
+ if (in_transaction(op[i], j)
+ || in_chainlock(op[i], j)) {
+ unsigned start = op[i][j].group_start;
+
+ /* Don't include twice. */
+ if (hash[h].num_users
+ && hash[h].user[hash[h].num_users-1].file
+ == i
+ && hash[h].user[hash[h].num_users-1].op_num
+ == start)
+ continue;
+
+ hash[h].user[hash[h].num_users].op_num = start;
+ } else
+ hash[h].user[hash[h].num_users].op_num = j;
hash[h].user[hash[h].num_users].file = i;
hash[h].num_users++;
}
return hash;
}
-static bool satisfies(const TDB_DATA *data, const TDB_DATA *need)
+static bool satisfies(const TDB_DATA *key, const TDB_DATA *data,
+ const struct op *op)
{
+ const TDB_DATA *need = NULL;
+
+ if (starts_transaction(op) || starts_chainlock(op)) {
+ unsigned int i;
+
+ /* Look through for an op in this transaction which
+ * needs this key. */
+ for (i = 1; i < op->group_len; i++) {
+ if (key_eq(op[i].key, *key)) {
+ need = needs(&op[i]);
+ /* tdb_exists() is special: there might be
+ * something in the transaction with more
+ * specific requirements. Other ops don't have
+ * specific requirements (eg. store or delete),
+ * but they change the value so we can't get
+ * more information from future ops. */
+ if (op[i].type != OP_TDB_EXISTS)
+ break;
+ }
+ }
+ } else
+ need = needs(op);
+
/* Don't need anything? Cool. */
if (!need)
return true;
assert(data != &must_not_exist);
assert(data != ¬_exists_or_empty);
- /* must_not_exist == must_not_exist, must_exist == must_exist, or
- not_exists_or_empty == not_exists_or_empty. */
- if (data->dsize == need->dsize && data->dptr == need->dptr)
- return true;
-
/* Must not exist? data must not exist. */
if (need == &must_not_exist)
- return data->dptr == NULL;
+ return data == &tdb_null;
/* Must exist? */
if (need == &must_exist)
- return data->dptr != NULL;
+ return data != &tdb_null;
/* Either noexist or empty. */
if (need == ¬_exists_or_empty)
return key_eq(*data, *need);
}
+static void move_to_front(struct op_desc res[], unsigned off, unsigned elem)
+{
+ if (elem != off) {
+ struct op_desc tmp = res[elem];
+ memmove(res + off + 1, res + off, (elem - off)*sizeof(res[0]));
+ res[off] = tmp;
+ }
+}
+
+static void restore_to_pos(struct op_desc res[], unsigned off, unsigned elem)
+{
+ if (elem != off) {
+ struct op_desc tmp = res[off];
+ memmove(res + off, res + off + 1, (elem - off)*sizeof(res[0]));
+ res[elem] = tmp;
+ }
+}
+
static bool sort_deps(char *filename[], struct op *op[],
- struct key_user res[], unsigned num,
- const TDB_DATA *data)
+ struct op_desc res[],
+ unsigned off, unsigned num,
+ const TDB_DATA *key, const TDB_DATA *data,
+ unsigned num_files, unsigned fuzz)
{
- unsigned int i;
+ unsigned int i, files_done;
+ struct op *this_op;
+ bool done[num_files];
- /* Nothing left? We're sorted. */
- if (num == 0)
+ /* None left? We're sorted. */
+ if (off == num)
return true;
- for (i = 0; i < num; i++) {
- struct op *this_op = &op[res[i].file][res[i].op_num];
+ /* Does this make sequence number go backwards? Allow a little fuzz. */
+ if (off > 0) {
+ int seqnum1 = op[res[off-1].file][res[off-1].op_num].seqnum;
+ int seqnum2 = op[res[off].file][res[off].op_num].seqnum;
+
+ if (seqnum1 - seqnum2 > (int)fuzz) {
+#if DEBUG_DEPS
+ printf("Seqnum jump too far (%u -> %u)\n",
+ seqnum1, seqnum2);
+#endif
+ return false;
+ }
+ }
+
+ memset(done, 0, sizeof(done));
+
+ /* Since ops within a trace file are ordered, we just need to figure
+ * out which file to try next. Since we don't take into account
+ * inter-key relationships (which exist by virtue of trace file order),
+ * we minimize the chance of harm by trying to keep in seqnum order. */
+ for (files_done = 0, i = off; i < num && files_done < num_files; i++) {
+ if (done[res[i].file])
+ continue;
+
+ this_op = &op[res[i].file][res[i].op_num];
/* Is what we have good enough for this op? */
- if (satisfies(data, needs(this_op))) {
- /* Try this one next. */
- struct key_user tmp = res[0];
- res[0] = res[i];
- res[i] = tmp;
- if (sort_deps(filename, op, res+1, num-1,
- gives(this_op, data)))
+ if (satisfies(key, data, this_op)) {
+ move_to_front(res, off, i);
+ if (sort_deps(filename, op, res, off+1, num,
+ key, gives(key, data, this_op),
+ num_files, fuzz))
return true;
+ restore_to_pos(res, off, i);
}
+ done[res[i].file] = true;
+ files_done++;
}
+
/* No combination worked. */
return false;
}
-/* All these ops have the same serial number. Which comes first?
+static void check_dep_sorting(struct op_desc user[], unsigned num_users,
+ unsigned num_files)
+{
+#if DEBUG_DEPS
+ unsigned int i;
+ unsigned minima[num_files];
+
+ memset(minima, 0, sizeof(minima));
+ for (i = 0; i < num_users; i++) {
+ assert(minima[user[i].file] < user[i].op_num);
+ minima[user[i].file] = user[i].op_num;
+ }
+#endif
+}
+
+/* All these ops happen on the same key. Which comes first?
*
* This can happen both because read ops or failed write ops don't
- * change serial number, and also due to race since we access the
+ * change sequence number, and also due to race since we access the
* number unlocked (the race can cause less detectable ordering problems,
* in which case we'll deadlock and report: fix manually in that case).
*/
static void figure_deps(char *filename[], struct op *op[],
- struct key_user user[], unsigned start, unsigned end)
+ const TDB_DATA *key, struct op_desc user[],
+ unsigned num_users, unsigned num_files)
{
- unsigned int i;
/* We assume database starts empty. */
const struct TDB_DATA *data = &tdb_null;
+ unsigned int fuzz;
- /* What do we have to start with? */
- for (i = 0; i < start; i++)
- data = gives(&op[user[i].file][user[i].op_num], data);
+ /* We prefer to keep strict seqnum order if possible: it's the
+ * most likely. We get more lax if that fails. */
+ for (fuzz = 0; fuzz < 100; fuzz = (fuzz + 1)*2) {
+ if (sort_deps(filename, op, user, 0, num_users, key, data,
+ num_files, fuzz))
+ break;
+ }
- if (!sort_deps(filename, op, user + start, end - start, data))
- fail(filename[user[start].file], user[start].op_num+1,
+ if (fuzz >= 100)
+ fail(filename[user[0].file], user[0].op_num+1,
"Could not resolve inter-dependencies");
+
+ check_dep_sorting(user, num_users, num_files);
}
-static void sort_ops(struct keyinfo hash[], char *filename[], struct op *op[])
+static void sort_ops(struct keyinfo hash[], char *filename[], struct op *op[],
+ unsigned int num)
{
unsigned int h;
/* Gcc nexted function extension. How cool is this? */
- int compare_serial(const void *_a, const void *_b)
+ int compare_seqnum(const void *_a, const void *_b)
{
- const struct key_user *a = _a, *b = _b;
- return op[a->file][a->op_num].serial
- - op[b->file][b->op_num].serial;
+ const struct op_desc *a = _a, *b = _b;
+
+ /* First, maintain order within any trace file. */
+ if (a->file == b->file)
+ return a->op_num - b->op_num;
+
+ /* Otherwise, arrange by seqnum order. */
+ if (op[a->file][a->op_num].seqnum !=
+ op[b->file][b->op_num].seqnum)
+ return op[a->file][a->op_num].seqnum
+ - op[b->file][b->op_num].seqnum;
+
+ /* Cancelled transactions are assumed to happen first. */
+ if (starts_transaction(&op[a->file][a->op_num])
+ && !successful_transaction(&op[a->file][a->op_num]))
+ return -1;
+ if (starts_transaction(&op[b->file][b->op_num])
+ && !successful_transaction(&op[b->file][b->op_num]))
+ return 1;
+
+ /* No idea. */
+ return 0;
}
/* Now sort into seqnum order. */
for (h = 0; h < total_keys * 2; h++) {
- unsigned int i, same;
- struct key_user *user = hash[h].user;
-
- qsort(user, hash[h].num_users, sizeof(user[0]), compare_serial);
+ struct op_desc *user = hash[h].user;
- /* Try to deal with same serial numbers. */
- for (i = 1, same = 0; i < hash[h].num_users; i++) {
- if (op[user[i].file][user[i].op_num].serial
- == op[user[i-1].file][user[i-1].op_num].serial) {
- same++;
- continue;
- }
-
- if (same) {
- figure_deps(filename, op, user, i-same-1, i);
- same = 0;
- }
- }
- if (same)
- figure_deps(filename, op, user, i-same-1, i);
+ qsort(user, hash[h].num_users, sizeof(user[0]), compare_seqnum);
+ figure_deps(filename, op, &hash[h].key, user, hash[h].num_users,
+ num);
}
}
return 0;
}
-static unsigned int dep_count;
static void add_dependency(void *ctx,
struct op *op[],
char *filename[],
- unsigned int needs_file,
- unsigned int needs_opnum,
- unsigned int satisfies_file,
- unsigned int satisfies_opnum)
+ const struct op_desc *needs,
+ const struct op_desc *prereq)
{
struct depend *dep;
- unsigned int needs_start, sat_start;
/* We don't depend on ourselves. */
- if (needs_file == satisfies_file)
+ if (needs->file == prereq->file) {
+ assert(prereq->op_num < needs->op_num);
return;
+ }
#if DEBUG_DEPS
printf("%s:%u: depends on %s:%u\n",
- filename[needs_file], needs_opnum+1,
- filename[satisfies_file], satisfies_opnum+1);
+ filename[needs->file], needs->op_num+1,
+ filename[prereq->file], prereq->op_num+1);
#endif
- needs_start = op[needs_file][needs_opnum].group_start;
- sat_start = op[satisfies_file][satisfies_opnum].group_start;
+ dep = talloc(ctx, struct depend);
+ dep->needs = *needs;
+ dep->prereq = *prereq;
- /* If needs is in a transaction, we need it before start. */
- if (needs_start) {
- switch (op[needs_file][needs_start].op) {
- case OP_TDB_TRANSACTION_START:
- needs_opnum = needs_start;
-#ifdef DEBUG_DEPS
- printf(" -> Back to %u\n", needs_start+1);
- fflush(stdout);
-#endif
- break;
- default:
- break;
- }
+#if TRAVERSALS_TAKE_TRANSACTION_LOCK
+ /* If something in a traverse depends on something in another
+ * traverse/transaction, it creates a dependency between the
+ * two groups. */
+ if ((in_traverse(op[prereq->file], prereq->op_num)
+ && (starts_transaction(&op[needs->file][needs->op_num])
+ || starts_traverse(&op[needs->file][needs->op_num])))
+ || (in_traverse(op[needs->file], needs->op_num)
+ && (starts_transaction(&op[prereq->file][prereq->op_num])
+ || starts_traverse(&op[prereq->file][prereq->op_num])))) {
+ unsigned int start;
+
+ /* We are satisfied by end of group. */
+ start = op[prereq->file][prereq->op_num].group_start;
+ dep->prereq.op_num = start + op[prereq->file][start].group_len;
+ /* And we need that done by start of our group. */
+ dep->needs.op_num = op[needs->file][needs->op_num].group_start;
}
- /* If satisfies is in a transaction, we wait until after commit. */
- /* FIXME: If transaction is cancelled, don't need dependency. */
- if (sat_start) {
- if (op[satisfies_file][sat_start].op
- == OP_TDB_TRANSACTION_START) {
- satisfies_opnum
- = op[satisfies_file][sat_start].transaction_end;
-#ifdef DEBUG_DEPS
- printf(" -> Depends on %u\n", satisfies_opnum+1);
- fflush(stdout);
-#endif
+ /* There is also this case:
+ * <traverse> <read foo> ...
+ * <transaction> ... </transaction> <create foo>
+ * Where if we start the traverse then wait, we could block
+ * the transaction and deadlock.
+ *
+ * We try to address this by ensuring that where seqnum indicates it's
+ * possible, we wait for <create foo> before *starting* traverse.
+ */
+ else if (in_traverse(op[needs->file], needs->op_num)) {
+ struct op *need = &op[needs->file][needs->op_num];
+ if (op[needs->file][need->group_start].seqnum >
+ op[prereq->file][prereq->op_num].seqnum) {
+ dep->needs.op_num = need->group_start;
}
}
+#endif
- dep = talloc(ctx, struct depend);
- dep->needs_file = needs_file;
- dep->needs_opnum = needs_opnum;
- dep->satisfies_file = satisfies_file;
- dep->satisfies_opnum = satisfies_opnum;
- list_add(&op[satisfies_file][satisfies_opnum].post, &dep->post_list);
- list_add(&op[needs_file][needs_opnum].pre, &dep->pre_list);
+ /* If you depend on a transaction or chainlock, you actually
+ * depend on it ending. */
+ if (starts_transaction(&op[prereq->file][dep->prereq.op_num])
+ || starts_chainlock(&op[prereq->file][dep->prereq.op_num])) {
+ dep->prereq.op_num
+ += op[dep->prereq.file][dep->prereq.op_num].group_len;
+#if DEBUG_DEPS
+ printf("-> Actually end of transaction %s:%u\n",
+ filename[dep->prereq->file], dep->prereq->op_num+1);
+#endif
+ } else
+ /* We should never create a dependency from middle of
+ * a transaction. */
+ assert(!in_transaction(op[prereq->file], dep->prereq.op_num)
+ || op[prereq->file][dep->prereq.op_num].type
+ == OP_TDB_TRANSACTION_COMMIT
+ || op[prereq->file][dep->prereq.op_num].type
+ == OP_TDB_TRANSACTION_CANCEL);
+
+ list_add(&op[dep->prereq.file][dep->prereq.op_num].post,
+ &dep->post_list);
+ list_add(&op[dep->needs.file][dep->needs.op_num].pre,
+ &dep->pre_list);
talloc_set_destructor(dep, destroy_depend);
+}
- dep_count++;
+static bool changes_db(const TDB_DATA *key, const struct op *op)
+{
+ return gives(key, NULL, op) != NULL;
}
-#if TRAVERSALS_TAKE_TRANSACTION_LOCK
-struct traverse_dep {
- unsigned int file;
- unsigned int op_num;
- const struct op *op;
-};
+static void depend_on_previous(struct op *op[],
+ char *filename[],
+ unsigned int num,
+ struct op_desc user[],
+ unsigned int i,
+ int prev)
+{
+ bool deps[num];
+ int j;
-/* Sort by which one runs first. */
-static int compare_traverse_dep(const void *_a, const void *_b)
+ if (i == 0)
+ return;
+
+ if (prev == i - 1) {
+ /* Just depend on previous. */
+ add_dependency(NULL, op, filename, &user[i], &user[prev]);
+ return;
+ }
+
+ /* We have to wait for the readers. Find last one in *each* file. */
+ memset(deps, 0, sizeof(deps));
+ deps[user[i].file] = true;
+ for (j = i - 1; j > prev; j--) {
+ if (!deps[user[j].file]) {
+ add_dependency(NULL, op, filename, &user[i], &user[j]);
+ deps[user[j].file] = true;
+ }
+ }
+}
+
+/* This is simple, but not complete. We don't take into account
+ * indirect dependencies. */
+static void optimize_dependencies(struct op *op[], unsigned int num_ops[],
+ unsigned int num)
{
- const struct traverse_dep *a = _a, *b = _b;
- const struct traverse *trava = a->op->trav, *travb = b->op->trav;
+ unsigned int i, j;
+
+ /* There can only be one real dependency on each file */
+ for (i = 0; i < num; i++) {
+ for (j = 1; j < num_ops[i]; j++) {
+ struct depend *dep, *next;
+ struct depend *prev[num];
+
+ memset(prev, 0, sizeof(prev));
- if (a->op->serial != b->op->serial)
- return a->op->serial - b->op->serial;
+ list_for_each_safe(&op[i][j].pre, dep, next, pre_list) {
+ if (!prev[dep->prereq.file]) {
+ prev[dep->prereq.file] = dep;
+ continue;
+ }
+ if (prev[dep->prereq.file]->prereq.op_num
+ < dep->prereq.op_num) {
+ talloc_free(prev[dep->prereq.file]);
+ prev[dep->prereq.file] = dep;
+ } else
+ talloc_free(dep);
+ }
+ }
+ }
+
+ for (i = 0; i < num; i++) {
+ int deps[num];
- /* If they have same serial, it means one didn't make any changes.
- * Thus sort by end in that case. */
- return a->op[trava->end - a->op_num].serial
- - b->op[travb->end - b->op_num].serial;
+ for (j = 0; j < num; j++)
+ deps[j] = -1;
+
+ for (j = 1; j < num_ops[i]; j++) {
+ struct depend *dep, *next;
+
+ list_for_each_safe(&op[i][j].pre, dep, next, pre_list) {
+ if (deps[dep->prereq.file]
+ >= (int)dep->prereq.op_num)
+ talloc_free(dep);
+ else
+ deps[dep->prereq.file]
+ = dep->prereq.op_num;
+ }
+ }
+ }
}
-/* Traversals can deadlock against each other. Force order. */
+#if TRAVERSALS_TAKE_TRANSACTION_LOCK
+/* Force an order among the traversals, so they don't deadlock (as much) */
static void make_traverse_depends(char *filename[],
struct op *op[], unsigned int num_ops[],
unsigned int num)
{
- unsigned int i, j, num_traversals = 0;
- struct traverse_dep *dep;
+ unsigned int i, num_traversals = 0;
+ int j;
+ struct op_desc *desc;
+
+ /* Sort by which one runs first. */
+ int compare_traverse_desc(const void *_a, const void *_b)
+ {
+ const struct op_desc *da = _a, *db = _b;
+ const struct op *a = &op[da->file][da->op_num],
+ *b = &op[db->file][db->op_num];
+
+ if (a->seqnum != b->seqnum)
+ return a->seqnum - b->seqnum;
+
+ /* If they have same seqnum, it means one didn't make any
+ * changes. Thus sort by end in that case. */
+ return a[a->group_len].seqnum - b[b->group_len].seqnum;
+ }
- dep = talloc_array(NULL, struct traverse_dep, 1);
+ desc = talloc_array(NULL, struct op_desc, 1);
/* Count them. */
for (i = 0; i < num; i++) {
- for (j = 0; j < num_ops[i]; j++) {
- if (op[i][j].op == OP_TDB_TRAVERSE_START
- || op[i][j].op == OP_TDB_TRAVERSE_READ_START) {
- dep = talloc_realloc(NULL, dep,
- struct traverse_dep,
- num_traversals+1);
- dep[num_traversals].file = i;
- dep[num_traversals].op_num = j;
- dep[num_traversals].op = &op[i][j];
+ for (j = 1; j < num_ops[i]; j++) {
+ /* Traverse start (ignore those in
+ * transactions; they're already covered by
+ * transaction dependencies). */
+ if (starts_traverse(&op[i][j])
+ && !in_transaction(op[i], j)) {
+ desc = talloc_realloc(NULL, desc,
+ struct op_desc,
+ num_traversals+1);
+ desc[num_traversals].file = i;
+ desc[num_traversals].op_num = j;
num_traversals++;
}
}
}
- qsort(dep, num_traversals, sizeof(dep[0]), compare_traverse_dep);
+ qsort(desc, num_traversals, sizeof(desc[0]), compare_traverse_desc);
+
for (i = 1; i < num_traversals; i++) {
- /* i depends on end of traverse i-1. */
- add_dependency(NULL, op, filename, dep[i].file, dep[i].op_num,
- dep[i-1].file, dep[i-1].op->trav->end);
+ const struct op *prev = &op[desc[i-1].file][desc[i-1].op_num];
+ const struct op *curr = &op[desc[i].file][desc[i].op_num];
+
+ /* Read traverses don't depend on each other (read lock). */
+ if (prev->type == OP_TDB_TRAVERSE_READ_START
+ && curr->type == OP_TDB_TRAVERSE_READ_START)
+ continue;
+
+ /* Only make dependency if it's clear. */
+ if (compare_traverse_desc(&desc[i], &desc[i-1])) {
+ /* i depends on end of traverse i-1. */
+ struct op_desc end = desc[i-1];
+ end.op_num += prev->group_len;
+ add_dependency(NULL, op, filename, &desc[i], &end);
+ }
}
- talloc_free(dep);
- printf("Dep count after traverses: %u\n", dep_count);
+ talloc_free(desc);
}
-#endif /* TRAVERSALS_TAKE_TRANSACTION_LOCK */
-static bool changes_db(const struct op *op)
+static void set_nonblock(int fd)
{
- return gives(op, NULL) != NULL;
+ if (fcntl(fd, F_SETFL, fcntl(fd, F_GETFL)|O_NONBLOCK) != 0)
+ err(1, "Setting pipe nonblocking");
}
-static void depend_on_previous(struct op *op[],
- char *filename[],
- unsigned int num,
- struct key_user user[],
- unsigned int i,
- int prev)
+static bool handle_backoff(struct op *op[], int fd)
{
- bool deps[num];
- int j;
-
- if (i == 0)
- return;
-
- if (prev == i - 1) {
- /* Just depend on previous. */
- add_dependency(NULL, op, filename,
- user[i].file, user[i].op_num,
- user[prev].file, user[prev].op_num);
- return;
- }
-
- /* We have to wait for the readers. Find last one in *each* file. */
- memset(deps, 0, sizeof(deps));
- deps[user[i].file] = true;
- for (j = i - 1; j > prev; j--) {
- if (!deps[user[j].file]) {
- add_dependency(NULL, op, filename,
- user[i].file, user[i].op_num,
- user[j].file, user[j].op_num);
- deps[user[j].file] = true;
+ struct op_desc desc;
+ bool handled = false;
+
+ /* Sloppy coding: we assume PIPEBUF never fills. */
+ while (read(fd, &desc, sizeof(desc)) != -1) {
+ unsigned int i;
+ handled = true;
+ for (i = desc.op_num; i > 0; i--) {
+ if (op[desc.file][i].type == OP_TDB_TRAVERSE) {
+ /* We insert a fake end here. */
+ op[desc.file][i].type
+ = OP_TDB_TRAVERSE_END_EARLY;
+ break;
+ } else if (starts_traverse(&op[desc.file][i])) {
+ unsigned int start = i;
+ struct op tmp = op[desc.file][i];
+ /* Move the ops outside traverse. */
+ memmove(&op[desc.file][i],
+ &op[desc.file][i+1],
+ (desc.op_num-i-1) * sizeof(op[0][0]));
+ op[desc.file][desc.op_num] = tmp;
+ while (op[desc.file][i].group_start == start) {
+ op[desc.file][i++].group_start
+ = desc.op_num;
+ }
+ break;
+ }
}
}
+ return handled;
+}
+
+#else /* !TRAVERSALS_TAKE_TRANSACTION_LOCK */
+static bool handle_backoff(struct op *op[], int fd)
+{
+ return false;
}
+#endif
static void derive_dependencies(char *filename[],
struct op *op[], unsigned int num_ops[],
/* Create hash table for faster key lookup. */
hash = hash_ops(op, num_ops, num);
- /* Now handle the hard cases: same serial number. */
- sort_ops(hash, filename, op);
+ /* Sort them by sequence number. */
+ sort_ops(hash, filename, op, num);
/* Create dependencies back to the last change, rather than
* creating false dependencies by naively making each one
continue;
for (i = 0; i < hash[h].num_users; i++) {
- if (changes_db(&op[hash[h].user[i].file]
+ if (changes_db(&hash[h].key, &op[hash[h].user[i].file]
[hash[h].user[i].op_num])) {
depend_on_previous(op, filename, num,
hash[h].user, i, prev);
prev = i;
} else if (prev >= 0)
add_dependency(hash, op, filename,
- hash[h].user[i].file,
- hash[h].user[i].op_num,
- hash[h].user[prev].file,
- hash[h].user[prev].op_num);
+ &hash[h].user[i],
+ &hash[h].user[prev]);
}
}
- printf("Dep count after deriving: %u\n", dep_count);
#if TRAVERSALS_TAKE_TRANSACTION_LOCK
make_traverse_depends(filename, op, num_ops, num);
#endif
+
+ optimize_dependencies(op, num_ops, num);
}
-int main(int argc, char *argv[])
+static struct timeval run_test(char *argv[],
+ unsigned int num_ops[],
+ unsigned int hashsize[],
+ unsigned int tdb_flags[],
+ unsigned int open_flags[],
+ struct op *op[],
+ int fds[2])
{
- struct timeval start, end;
- unsigned int i, num_ops[argc], hashsize[argc], tdb_flags[argc], open_flags[argc];
- struct op *op[argc];
- int fds[2];
- char c;
+ unsigned int i;
+ struct timeval start, end, diff;
bool ok = true;
- if (argc < 3)
- errx(1, "Usage: %s <tdbfile> <tracefile>...", argv[0]);
-
- pipes = talloc_array(NULL, struct pipe, argc - 2);
- for (i = 0; i < argc - 2; i++) {
- printf("Loading tracefile %s...", argv[2+i]);
- fflush(stdout);
- op[i] = load_tracefile(argv[2+i], &num_ops[i], &hashsize[i],
- &tdb_flags[i], &open_flags[i]);
- if (pipe(pipes[i].fd) != 0)
- err(1, "creating pipe");
- printf("done\n");
- }
-
- printf("Calculating inter-dependencies...");
- fflush(stdout);
- derive_dependencies(argv+2, op, num_ops, i);
- printf("done\n");
-
- /* Don't fork for single arg case: simple debugging. */
- if (argc == 3) {
- struct tdb_context *tdb;
- tdb = tdb_open_ex(argv[1], hashsize[0], tdb_flags[0],
- open_flags[0], 0600,
- NULL, hash_key);
- printf("Single threaded run...");
- fflush(stdout);
-
- run_ops(tdb, pipes[0].fd[0], argv+2, 0, op[0], 1, num_ops[0]);
- check_deps(argv[2], op[0], num_ops[0]);
-
- printf("done\n");
- exit(0);
- }
-
- if (pipe(fds) != 0)
- err(1, "creating pipe");
-
- for (i = 0; i < argc - 2; i++) {
+ for (i = 0; argv[i+2]; i++) {
struct tdb_context *tdb;
+ char c;
switch (fork()) {
case -1:
err(1, "fork failed");
case 0:
close(fds[1]);
- tdb = tdb_open_ex(argv[1], hashsize[i], tdb_flags[i],
- open_flags[i], 0600,
- NULL, hash_key);
+ tdb = tdb_open_ex(argv[1], hashsize[i],
+ tdb_flags[i]|TDB_NOSYNC,
+ open_flags[i], 0600, NULL, hash_key);
if (!tdb)
err(1, "Opening tdb %s", argv[1]);
/* This catches parent exiting. */
if (read(fds[0], &c, 1) != 1)
exit(1);
- run_ops(tdb, pipes[i].fd[0], argv+2, i, op[i], 1,
- num_ops[i]);
+ run_ops(tdb, pipes[i].fd[0], argv+2, op, i, 1,
+ num_ops[i], false);
check_deps(argv[2+i], op[i], num_ops[i]);
exit(0);
default:
if (write(fds[1], hashsize, i) != i)
err(1, "Writing to wakeup pipe");
- for (i = 0; i < argc - 2; i++) {
+ for (i = 0; argv[i + 2]; i++) {
int status;
wait(&status);
if (!WIFEXITED(status)) {
gettimeofday(&end, NULL);
printf("done\n");
- end.tv_sec -= start.tv_sec;
+ if (end.tv_usec < start.tv_usec) {
+ end.tv_usec += 1000000;
+ end.tv_sec--;
+ }
+ diff.tv_sec = end.tv_sec - start.tv_sec;
+ diff.tv_usec = end.tv_usec - start.tv_usec;
+ return diff;
+}
+
+int main(int argc, char *argv[])
+{
+ struct timeval diff;
+ unsigned int i, num_ops[argc], hashsize[argc], tdb_flags[argc], open_flags[argc];
+ struct op *op[argc];
+ int fds[2];
+
+ if (argc < 3)
+ errx(1, "Usage: %s <tdbfile> <tracefile>...", argv[0]);
+
+ pipes = talloc_array(NULL, struct pipe, argc - 1);
+ for (i = 0; i < argc - 2; i++) {
+ printf("Loading tracefile %s...", argv[2+i]);
+ fflush(stdout);
+ op[i] = load_tracefile(argv[2+i], &num_ops[i], &hashsize[i],
+ &tdb_flags[i], &open_flags[i]);
+ if (pipe(pipes[i].fd) != 0)
+ err(1, "creating pipe");
+ printf("done\n");
+ }
+
+ printf("Calculating inter-dependencies...");
+ fflush(stdout);
+ derive_dependencies(argv+2, op, num_ops, i);
+ printf("done\n");
+
+ /* Don't fork for single arg case: simple debugging. */
+ if (argc == 3) {
+ struct tdb_context *tdb;
+ tdb = tdb_open_ex(argv[1], hashsize[0], tdb_flags[0]|TDB_NOSYNC,
+ open_flags[0], 0600, NULL, hash_key);
+ printf("Single threaded run...");
+ fflush(stdout);
+
+ run_ops(tdb, pipes[0].fd[0], argv+2, op, 0, 1, num_ops[0],
+ false);
+ check_deps(argv[2], op[0], num_ops[0]);
+
+ printf("done\n");
+ exit(0);
+ }
+
+ if (pipe(fds) != 0)
+ err(1, "creating pipe");
+
+#if TRAVERSALS_TAKE_TRANSACTION_LOCK
+ if (pipe(pipes[argc-2].fd) != 0)
+ err(1, "creating pipe");
+ backoff_fd = pipes[argc-2].fd[1];
+ set_nonblock(pipes[argc-2].fd[1]);
+ set_nonblock(pipes[argc-2].fd[0]);
+#endif
+
+ do {
+ diff = run_test(argv, num_ops, hashsize, tdb_flags, open_flags,
+ op, fds);
+ } while (handle_backoff(op, pipes[argc-2].fd[0]));
+
printf("Time replaying: %lu usec\n",
- end.tv_sec * 1000000UL + (end.tv_usec - start.tv_usec));
+ diff.tv_sec * 1000000UL + diff.tv_usec);
exit(0);
}
projects / ccan / blobdiff