diff options
| -rw-r--r-- | Documentation/config/reftable.txt | 8 | ||||
| -rw-r--r-- | refs/reftable-backend.c | 8 | ||||
| -rw-r--r-- | reftable/reftable-writer.h | 11 | ||||
| -rw-r--r-- | reftable/stack.c | 18 | ||||
| -rwxr-xr-x | t/t0610-reftable-basics.sh | 27 |
5 files changed, 66 insertions, 6 deletions
diff --git a/Documentation/config/reftable.txt b/Documentation/config/reftable.txt index 0515727977..57087803a5 100644 --- a/Documentation/config/reftable.txt +++ b/Documentation/config/reftable.txt @@ -46,3 +46,11 @@ reftable.geometricFactor:: By default, the geometric sequence uses a factor of 2, meaning that for any table, the next-biggest table must at least be twice as big. A maximum factor of 256 is supported. + +reftable.lockTimeout:: + Whenever the reftable backend appends a new table to the stack, it has + to lock the central "tables.list" file before updating it. This config + controls how long the process will wait to acquire the lock in case + another process has already acquired it. Value 0 means not to retry at + all; -1 means to try indefinitely. Default is 100 (i.e., retry for + 100ms). diff --git a/refs/reftable-backend.c b/refs/reftable-backend.c index 1c4b19e737..ca281e39a2 100644 --- a/refs/reftable-backend.c +++ b/refs/reftable-backend.c @@ -256,6 +256,13 @@ static int reftable_be_config(const char *var, const char *value, if (factor > UINT8_MAX) die("reftable geometric factor cannot exceed %u", (unsigned)UINT8_MAX); opts->auto_compaction_factor = factor; + } else if (!strcmp(var, "reftable.locktimeout")) { + int64_t lock_timeout = git_config_int64(var, value, ctx->kvi); + if (lock_timeout > LONG_MAX) + die("reftable lock timeout cannot exceed %"PRIdMAX, (intmax_t)LONG_MAX); + if (lock_timeout < 0 && lock_timeout != -1) + die("reftable lock timeout does not support negative values other than -1"); + opts->lock_timeout_ms = lock_timeout; } return 0; @@ -281,6 +288,7 @@ static struct ref_store *reftable_be_init(struct repository *repo, refs->write_options.default_permissions = calc_shared_perm(0666 & ~mask); refs->write_options.disable_auto_compact = !git_env_bool("GIT_TEST_REFTABLE_AUTOCOMPACTION", 1); + refs->write_options.lock_timeout_ms = 100; git_config(reftable_be_config, &refs->write_options); diff --git a/reftable/reftable-writer.h b/reftable/reftable-writer.h index 189b1f4144..f5e25cfda1 100644 --- a/reftable/reftable-writer.h +++ b/reftable/reftable-writer.h @@ -51,6 +51,17 @@ struct reftable_write_options { * tables to compact. Defaults to 2 if unset. */ uint8_t auto_compaction_factor; + + /* + * The number of milliseconds to wait when trying to lock "tables.list". + * Note that this does not apply to locking individual tables, as these + * should only ever be locked when already holding the "tables.list" + * lock. + * + * Passing 0 will fail immediately when the file is locked, passing a + * negative value will cause us to block indefinitely. + */ + long lock_timeout_ms; }; /* reftable_block_stats holds statistics for a single block type */ diff --git a/reftable/stack.c b/reftable/stack.c index ce0a35216b..5ccad2cff3 100644 --- a/reftable/stack.c +++ b/reftable/stack.c @@ -603,8 +603,10 @@ static int reftable_stack_init_addition(struct reftable_addition *add, add->stack = st; - err = hold_lock_file_for_update(&add->tables_list_lock, st->list_file, - LOCK_NO_DEREF); + err = hold_lock_file_for_update_timeout(&add->tables_list_lock, + st->list_file, + LOCK_NO_DEREF, + st->opts.lock_timeout_ms); if (err < 0) { if (errno == EEXIST) { err = REFTABLE_LOCK_ERROR; @@ -1056,8 +1058,10 @@ static int stack_compact_range(struct reftable_stack *st, * Hold the lock so that we can read "tables.list" and lock all tables * which are part of the user-specified range. */ - err = hold_lock_file_for_update(&tables_list_lock, st->list_file, - LOCK_NO_DEREF); + err = hold_lock_file_for_update_timeout(&tables_list_lock, + st->list_file, + LOCK_NO_DEREF, + st->opts.lock_timeout_ms); if (err < 0) { if (errno == EEXIST) err = REFTABLE_LOCK_ERROR; @@ -1156,8 +1160,10 @@ static int stack_compact_range(struct reftable_stack *st, * "tables.list". We'll then replace the compacted range of tables with * the new table. */ - err = hold_lock_file_for_update(&tables_list_lock, st->list_file, - LOCK_NO_DEREF); + err = hold_lock_file_for_update_timeout(&tables_list_lock, + st->list_file, + LOCK_NO_DEREF, + st->opts.lock_timeout_ms); if (err < 0) { if (errno == EEXIST) err = REFTABLE_LOCK_ERROR; diff --git a/t/t0610-reftable-basics.sh b/t/t0610-reftable-basics.sh index 37510c2b2a..62da3e3782 100755 --- a/t/t0610-reftable-basics.sh +++ b/t/t0610-reftable-basics.sh @@ -423,6 +423,33 @@ test_expect_success 'ref transaction: fails gracefully when auto compaction fail ) ' +test_expect_success 'ref transaction: timeout acquiring tables.list lock' ' + test_when_finished "rm -rf repo" && + git init repo && + ( + cd repo && + test_commit initial && + >.git/reftable/tables.list.lock && + test_must_fail git update-ref refs/heads/branch HEAD 2>err && + test_grep "cannot lock references" err + ) +' + +test_expect_success 'ref transaction: retry acquiring tables.list lock' ' + test_when_finished "rm -rf repo" && + git init repo && + ( + cd repo && + test_commit initial && + LOCK=.git/reftable/tables.list.lock && + >$LOCK && + { + ( sleep 1 && rm -f $LOCK ) & + } && + git -c reftable.lockTimeout=5000 update-ref refs/heads/branch HEAD + ) +' + test_expect_success 'pack-refs: compacts tables' ' test_when_finished "rm -rf repo" && git init repo && |