bulk-checkin: rebrand plug/unplug APIs as 'odb transactions'

Make it clearer in the naming and documentation of the plug_bulk_checkin
and unplug_bulk_checkin APIs that they can be thought of as
a "transaction" to optimize operations on the object database. These
transactions may be nested so that subsystems like the cache-tree
writing code can optimize their operations without caring whether the
top-level code has a transaction active.

Add a flush_odb_transaction API that will be used in update-index to
make objects visible even if a transaction is active. The flush call may
also be useful in future cases if we hold a transaction active around
calling hooks.

Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/add.c b/builtin/add.c
index 3ffb86a43384f21cad4fdcc0d8549e37dba12227..9bf37ceae8e2fc23e7fe0ddf587906a29b5dfba3 100644 (file)
--- a/builtin/add.c
+++ b/builtin/add.c
@@ -670,7 +670,7 @@ int cmd_add(int argc, const char **argv, const char *prefix)
                string_list_clear(&only_match_skip_worktree, 0);
        }
 
-       plug_bulk_checkin();
+       begin_odb_transaction();
 
        if (add_renormalize)
                exit_status |= renormalize_tracked_files(&pathspec, flags);
@@ -682,7 +682,7 @@ int cmd_add(int argc, const char **argv, const char *prefix)
 
        if (chmod_arg && pathspec.nr)
                exit_status |= chmod_pathspec(&pathspec, chmod_arg[0], show_only);
-       unplug_bulk_checkin();
+       end_odb_transaction();
 
 finish:
        if (write_locked_index(&the_index, &lock_file,

diff --git a/bulk-checkin.c b/bulk-checkin.c
index 81560e87d95ae9b71fc556a9a919918f623bf0be..ad855267d29bf36baf3b3c9ef4110f8e7dbac370 100644 (file)
--- a/bulk-checkin.c
+++ b/bulk-checkin.c
@@ -10,7 +10,7 @@
 #include "packfile.h"
 #include "object-store.h"
 
-static int bulk_checkin_plugged;
+static int odb_transaction_nesting;
 
 static struct bulk_checkin_packfile {
        char *pack_tmp_name;
@@ -280,20 +280,29 @@ int index_bulk_checkin(struct object_id *oid,
 {
        int status = deflate_to_pack(&bulk_checkin_packfile, oid, fd, size, type,
                                     path, flags);
-       if (!bulk_checkin_plugged)
+       if (!odb_transaction_nesting)
                flush_bulk_checkin_packfile(&bulk_checkin_packfile);
        return status;
 }
 
-void plug_bulk_checkin(void)
+void begin_odb_transaction(void)
 {
-       assert(!bulk_checkin_plugged);
-       bulk_checkin_plugged = 1;
+       odb_transaction_nesting += 1;
 }
 
-void unplug_bulk_checkin(void)
+void flush_odb_transaction(void)
 {
-       assert(bulk_checkin_plugged);
-       bulk_checkin_plugged = 0;
        flush_bulk_checkin_packfile(&bulk_checkin_packfile);
 }
+
+void end_odb_transaction(void)
+{
+       odb_transaction_nesting -= 1;
+       if (odb_transaction_nesting < 0)
+               BUG("Unbalanced ODB transaction nesting");
+
+       if (odb_transaction_nesting)
+               return;
+
+       flush_odb_transaction();
+}

diff --git a/bulk-checkin.h b/bulk-checkin.h
index b26f3dc3b74cb9ccb4ea630fafe8cd0cdcf5a012..ee0832989a8d7567a8fc6b75419bb668261ed2a6 100644 (file)
--- a/bulk-checkin.h
+++ b/bulk-checkin.h
@@ -10,7 +10,27 @@ int index_bulk_checkin(struct object_id *oid,
                       int fd, size_t size, enum object_type type,
                       const char *path, unsigned flags);
 
-void plug_bulk_checkin(void);
-void unplug_bulk_checkin(void);
+/*
+ * Tell the object database to optimize for adding
+ * multiple objects. end_odb_transaction must be called
+ * to make new objects visible. Transactions can be nested,
+ * and objects are only visible after the outermost transaction
+ * is complete or the transaction is flushed.
+ */
+void begin_odb_transaction(void);
+
+/*
+ * Make any objects that are currently part of a pending object
+ * database transaction visible. It is valid to call this function
+ * even if no transaction is active.
+ */
+void flush_odb_transaction(void);
+
+/*
+ * Tell the object database to make any objects from the
+ * current transaction visible if this is the final nested
+ * transaction.
+ */
+void end_odb_transaction(void);
 
 #endif