6 files changed, 62 insertions, 14 deletions
diff --git a/Documentation/config/gc.txt b/Documentation/config/gc.txt
index 664a3c2874..1d4f9470ea 100644
--- a/Documentation/config/gc.txt
+++ b/Documentation/config/gc.txt
@@ -40,7 +40,8 @@ use, it'll affect how the auto pack limit works.
 
 gc.autoDetach::
 	Make `git gc --auto` return immediately and run in the background
-	if the system supports it. Default is true.
+	if the system supports it. Default is true. This config variable acts
+	as a fallback in case `maintenance.autoDetach` is not set.
 
 gc.bigPackThreshold::
 	If non-zero, all non-cruft packs larger than this limit are kept
diff --git a/Documentation/config/maintenance.txt b/Documentation/config/maintenance.txt
index 69a4f05153..72a9d6cf81 100644
--- a/Documentation/config/maintenance.txt
+++ b/Documentation/config/maintenance.txt
@@ -3,6 +3,17 @@ maintenance.auto::
 	`git maintenance run --auto` after doing their normal work. Defaults
 	to true.
 
+maintenance.autoDetach::
+	Many Git commands trigger automatic maintenance after they have
+	written data into the repository. This boolean config option
+	controls whether this automatic maintenance shall happen in the
+	foreground or whether the maintenance process shall detach and
+	continue to run in the background.
++
+If unset, the value of `gc.autoDetach` is used as a fallback. Defaults
+to true if both are unset, meaning that the maintenance process will
+detach.
+
 maintenance.strategy::
 	This string config option provides a way to specify one of a few
 	recommended schedules for background maintenance. This only affects
diff --git a/builtin/gc.c b/builtin/gc.c
index 63106e2028..bafee330a2 100644
--- a/builtin/gc.c
+++ b/builtin/gc.c
@@ -1063,6 +1063,7 @@ static int maintenance_task_gc(struct maintenance_run_opts *opts,
 		strvec_push(&child.args, "--quiet");
 	else
 		strvec_push(&child.args, "--no-quiet");
+	strvec_push(&child.args, "--no-detach");
 
 	return run_command(&child);
 }
diff --git a/run-command.c b/run-command.c
index 45ba544932..94f2f3079f 100644
--- a/run-command.c
+++ b/run-command.c
@@ -1808,16 +1808,26 @@ void run_processes_parallel(const struct run_process_parallel_opts *opts)
 
 int prepare_auto_maintenance(int quiet, struct child_process *maint)
 {
-	int enabled;
+	int enabled, auto_detach;
 
 	if (!git_config_get_bool("maintenance.auto", &enabled) &&
 	    !enabled)
 		return 0;
 
+	/*
+	 * When `maintenance.autoDetach` isn't set, then we fall back to
+	 * honoring `gc.autoDetach`. This is somewhat weird, but required to
+	 * retain behaviour from when we used to run git-gc(1) here.
+	 */
+	if (git_config_get_bool("maintenance.autodetach", &auto_detach) &&
+	    git_config_get_bool("gc.autodetach", &auto_detach))
+		auto_detach = 1;
+
 	maint->git_cmd = 1;
 	maint->close_object_store = 1;
 	strvec_pushl(&maint->args, "maintenance", "run", "--auto", NULL);
 	strvec_push(&maint->args, quiet ? "--quiet" : "--no-quiet");
+	strvec_push(&maint->args, auto_detach ? "--detach" : "--no-detach");
 
 	return 1;
 }
diff --git a/t/t5616-partial-clone.sh b/t/t5616-partial-clone.sh
index 2da7291e37..8415884754 100755
--- a/t/t5616-partial-clone.sh
+++ b/t/t5616-partial-clone.sh
@@ -229,7 +229,7 @@ test_expect_success 'fetch --refetch triggers repacking' '
 
 	GIT_TRACE2_EVENT="$PWD/trace1.event" \
 	git -C pc1 fetch --refetch origin &&
-	test_subcommand git maintenance run --auto --no-quiet <trace1.event &&
+	test_subcommand git maintenance run --auto --no-quiet --detach <trace1.event &&
 	grep \"param\":\"gc.autopacklimit\",\"value\":\"1\" trace1.event &&
 	grep \"param\":\"maintenance.incremental-repack.auto\",\"value\":\"-1\" trace1.event &&
 
@@ -238,7 +238,7 @@ test_expect_success 'fetch --refetch triggers repacking' '
 		-c gc.autoPackLimit=0 \
 		-c maintenance.incremental-repack.auto=1234 \
 		-C pc1 fetch --refetch origin &&
-	test_subcommand git maintenance run --auto --no-quiet <trace2.event &&
+	test_subcommand git maintenance run --auto --no-quiet --detach <trace2.event &&
 	grep \"param\":\"gc.autopacklimit\",\"value\":\"0\" trace2.event &&
 	grep \"param\":\"maintenance.incremental-repack.auto\",\"value\":\"-1\" trace2.event &&
 
@@ -247,7 +247,7 @@ test_expect_success 'fetch --refetch triggers repacking' '
 		-c gc.autoPackLimit=1234 \
 		-c maintenance.incremental-repack.auto=0 \
 		-C pc1 fetch --refetch origin &&
-	test_subcommand git maintenance run --auto --no-quiet <trace3.event &&
+	test_subcommand git maintenance run --auto --no-quiet --detach <trace3.event &&
 	grep \"param\":\"gc.autopacklimit\",\"value\":\"1\" trace3.event &&
 	grep \"param\":\"maintenance.incremental-repack.auto\",\"value\":\"0\" trace3.event
 '
diff --git a/t/t7900-maintenance.sh b/t/t7900-maintenance.sh
index 771525aa4b..06ab43cfb5 100755
--- a/t/t7900-maintenance.sh
+++ b/t/t7900-maintenance.sh
@@ -49,22 +49,47 @@ test_expect_success 'run [--auto|--quiet]' '
 		git maintenance run --auto 2>/dev/null &&
 	GIT_TRACE2_EVENT="$(pwd)/run-no-quiet.txt" \
 		git maintenance run --no-quiet 2>/dev/null &&
-	test_subcommand git gc --quiet <run-no-auto.txt &&
-	test_subcommand ! git gc --auto --quiet <run-auto.txt &&
-	test_subcommand git gc --no-quiet <run-no-quiet.txt
+	test_subcommand git gc --quiet --no-detach <run-no-auto.txt &&
+	test_subcommand ! git gc --auto --quiet --no-detach <run-auto.txt &&
+	test_subcommand git gc --no-quiet --no-detach <run-no-quiet.txt
 '
 
 test_expect_success 'maintenance.auto config option' '
 	GIT_TRACE2_EVENT="$(pwd)/default" git commit --quiet --allow-empty -m 1 &&
-	test_subcommand git maintenance run --auto --quiet <default &&
+	test_subcommand git maintenance run --auto --quiet --detach <default &&
 	GIT_TRACE2_EVENT="$(pwd)/true" \
 		git -c maintenance.auto=true \
 		commit --quiet --allow-empty -m 2 &&
-	test_subcommand git maintenance run --auto --quiet  <true &&
+	test_subcommand git maintenance run --auto --quiet --detach <true &&
 	GIT_TRACE2_EVENT="$(pwd)/false" \
 		git -c maintenance.auto=false \
 		commit --quiet --allow-empty -m 3 &&
-	test_subcommand ! git maintenance run --auto --quiet  <false
+	test_subcommand ! git maintenance run --auto --quiet --detach <false
+'
+
+for cfg in maintenance.autoDetach gc.autoDetach
+do
+	test_expect_success "$cfg=true config option" '
+		test_when_finished "rm -f trace" &&
+		test_config $cfg true &&
+		GIT_TRACE2_EVENT="$(pwd)/trace" git commit --quiet --allow-empty -m 1 &&
+		test_subcommand git maintenance run --auto --quiet --detach <trace
+	'
+
+	test_expect_success "$cfg=false config option" '
+		test_when_finished "rm -f trace" &&
+		test_config $cfg false &&
+		GIT_TRACE2_EVENT="$(pwd)/trace" git commit --quiet --allow-empty -m 1 &&
+		test_subcommand git maintenance run --auto --quiet --no-detach <trace
+	'
+done
+
+test_expect_success "maintenance.autoDetach overrides gc.autoDetach" '
+	test_when_finished "rm -f trace" &&
+	test_config maintenance.autoDetach false &&
+	test_config gc.autoDetach true &&
+	GIT_TRACE2_EVENT="$(pwd)/trace" git commit --quiet --allow-empty -m 1 &&
+	test_subcommand git maintenance run --auto --quiet --no-detach <trace
 '
 
 test_expect_success 'register uses XDG_CONFIG_HOME config if it exists' '
@@ -129,9 +154,9 @@ test_expect_success 'run --task=<task>' '
 		git maintenance run --task=commit-graph 2>/dev/null &&
 	GIT_TRACE2_EVENT="$(pwd)/run-both.txt" \
 		git maintenance run --task=commit-graph --task=gc 2>/dev/null &&
-	test_subcommand ! git gc --quiet <run-commit-graph.txt &&
-	test_subcommand git gc --quiet <run-gc.txt &&
-	test_subcommand git gc --quiet <run-both.txt &&
+	test_subcommand ! git gc --quiet --no-detach <run-commit-graph.txt &&
+	test_subcommand git gc --quiet --no-detach <run-gc.txt &&
+	test_subcommand git gc --quiet --no-detach <run-both.txt &&
 	test_subcommand git commit-graph write --split --reachable --no-progress <run-commit-graph.txt &&
 	test_subcommand ! git commit-graph write --split --reachable --no-progress <run-gc.txt &&
 	test_subcommand git commit-graph write --split --reachable --no-progress <run-both.txt