libpod: add GetConfigNoCopy()

Add a new function to libpod to directly access the runtime
configuration without creating an expensive deep copy.  Further migrate
a number of callers to this new function.

This drops the number of calls to JSONDeepCopy from 4 to 1 in a simple
`podman run --rm -d busybox top`.

Future work: Please note that there are more callers of GetConfig() that
can me migrated to GetConfigNoCopy().

[NO TESTS NEEDED]

Signed-off-by: Valentin Rothberg <rothberg@redhat.com>

2 files changed, 2 insertions, 2 deletions

diff --git a/pkg/specgen/generate/container.go b/pkg/specgen/generate/container.go
index ae26807a9..71b882510 100644
--- a/pkg/specgen/generate/container.go
+++ b/pkg/specgen/generate/container.go
@@ -54,7 +54,7 @@ func CompleteSpec(ctx context.Context, r *libpod.Runtime, s *specgen.SpecGenerat
 		}
 	}
 
-	rtc, err := r.GetConfig()
+	rtc, err := r.GetConfigNoCopy()
 	if err != nil {
 		return nil, err
 	}
diff --git a/pkg/specgen/generate/container_create.go b/pkg/specgen/generate/container_create.go
index b6263332e..6100e7a5b 100644
--- a/pkg/specgen/generate/container_create.go
+++ b/pkg/specgen/generate/container_create.go
@@ -23,7 +23,7 @@ import (
 // Returns the created, container and any warnings resulting from creating the
 // container, or an error.
 func MakeContainer(ctx context.Context, rt *libpod.Runtime, s *specgen.SpecGenerator) (*spec.Spec, *specgen.SpecGenerator, []libpod.CtrCreateOption, error) {
-	rtc, err := rt.GetConfig()
+	rtc, err := rt.GetConfigNoCopy()
 	if err != nil {
 		return nil, nil, nil, err
 	}