diff --git a/criu/cr-exec.c b/criu/cr-exec.c
index 4762a8b90..e5609abb0 100644
--- a/criu/cr-exec.c
+++ b/criu/cr-exec.c
@@ -169,7 +169,7 @@ int cr_exec(int pid, char **opt)
 		goto out_unseize;
 	}
 
-	ctl = parasite_prep_ctl(pid);
+	ctl = compel_prepare(pid);
 	if (!ctl) {
 		pr_err("Can't prep ctl %d\n", pid);
 		goto out_unseize;
diff --git a/criu/cr-restore.c b/criu/cr-restore.c
index 88ca34e57..503d32f64 100644
--- a/criu/cr-restore.c
+++ b/criu/cr-restore.c
@@ -1654,7 +1654,7 @@ static void finalize_restore(void)
 			continue;
 
 		/* Unmap the restorer blob */
-		ctl = parasite_prep_ctl(pid);
+		ctl = compel_prepare(pid);
 		if (ctl == NULL)
 			continue;
 
diff --git a/criu/include/infect.h b/criu/include/infect.h
index 9cfbfe084..fa6dac88c 100644
--- a/criu/include/infect.h
+++ b/criu/include/infect.h
@@ -24,7 +24,10 @@ extern int compel_wait_task(int pid, int ppid,
 #define TASK_ZOMBIE		0x6
 
 struct parasite_ctl;
+struct thread_ctx;
 
+extern struct parasite_ctl *compel_prepare(int pid);
 extern int compel_infect(struct parasite_ctl *ctl, unsigned long nr_threads, unsigned long args_size);
+extern int compel_prepare_thread(int pid, struct thread_ctx *ctx);
 
 #endif
diff --git a/criu/include/parasite-syscall.h b/criu/include/parasite-syscall.h
index 65d4217c2..9e151df87 100644
--- a/criu/include/parasite-syscall.h
+++ b/criu/include/parasite-syscall.h
@@ -98,7 +98,6 @@ extern struct parasite_ctl *parasite_infect_seized(pid_t pid,
 						   struct vm_area_list *vma_area_list);
 extern void parasite_ensure_args_size(unsigned long sz);
 extern unsigned long get_exec_start(struct vm_area_list *);
-extern struct parasite_ctl *parasite_prep_ctl(pid_t pid);
 extern int parasite_map_exchange(struct parasite_ctl *ctl, unsigned long size);
 
 extern int parasite_dump_cgroup(struct parasite_ctl *ctl, struct parasite_dump_cgroup_args *cgroup);
diff --git a/criu/infect.c b/criu/infect.c
index 3fc89df5d..4668884de 100644
--- a/criu/infect.c
+++ b/criu/infect.c
@@ -20,6 +20,9 @@
 #include "infect.h"
 #include "infect-priv.h"
 
+#define MEMFD_FNAME	"CRIUMFD"
+#define MEMFD_FNAME_SZ	sizeof(MEMFD_FNAME)
+
 /* XXX will be removed soon */
 extern int parasite_wait_ack(int sockfd, unsigned int cmd, struct ctl_msg *m);
 
@@ -527,3 +530,47 @@ err:
 	return -1;
 }
 
+int compel_prepare_thread(int pid, struct thread_ctx *ctx)
+{
+	if (ptrace(PTRACE_GETSIGMASK, pid, sizeof(k_rtsigset_t), &ctx->sigmask)) {
+		pr_perror("can't get signal blocking mask for %d", pid);
+		return -1;
+	}
+
+	if (ptrace_get_regs(pid, &ctx->regs)) {
+		pr_perror("Can't obtain registers (pid: %d)", pid);
+		return -1;
+	}
+
+	return 0;
+}
+
+struct parasite_ctl *compel_prepare(int pid)
+{
+	struct parasite_ctl *ctl = NULL;
+
+	/*
+	 * Control block early setup.
+	 */
+	ctl = xzalloc(sizeof(*ctl));
+	if (!ctl) {
+		pr_err("Parasite control block allocation failed (pid: %d)\n", pid);
+		goto err;
+	}
+
+	ctl->tsock = -1;
+
+	if (compel_prepare_thread(pid, &ctl->orig))
+		goto err;
+
+	ctl->rpid = pid;
+
+	BUILD_BUG_ON(PARASITE_START_AREA_MIN < BUILTIN_SYSCALL_SIZE + MEMFD_FNAME_SZ);
+
+	return ctl;
+
+err:
+	xfree(ctl);
+	return NULL;
+}
+
diff --git a/criu/parasite-syscall.c b/criu/parasite-syscall.c
index 62841a2aa..b1458ec24 100644
--- a/criu/parasite-syscall.c
+++ b/criu/parasite-syscall.c
@@ -91,21 +91,6 @@ static inline int ptrace_set_regs(int pid, user_regs_struct_t *regs)
 }
 #endif
 
-static int get_thread_ctx(int pid, struct thread_ctx *ctx)
-{
-	if (ptrace(PTRACE_GETSIGMASK, pid, sizeof(k_rtsigset_t), &ctx->sigmask)) {
-		pr_perror("can't get signal blocking mask for %d", pid);
-		return -1;
-	}
-
-	if (ptrace_get_regs(pid, &ctx->regs)) {
-		pr_perror("Can't obtain registers (pid: %d)", pid);
-		return -1;
-	}
-
-	return 0;
-}
-
 static int restore_thread_ctx(int pid, struct thread_ctx *ctx)
 {
 	int ret = 0;
@@ -481,7 +466,7 @@ int parasite_dump_thread_seized(struct parasite_ctl *ctl, int id,
 
 	pc->cap_last_cap = kdat.last_cap;
 
-	ret = get_thread_ctx(pid, &octx);
+	ret = compel_prepare_thread(pid, &octx);
 	if (ret)
 		return -1;
 
@@ -1071,36 +1056,6 @@ err:
 	return ret;
 }
 
-/* If vma_area_list is NULL, a place for injecting syscall will not be set. */
-struct parasite_ctl *parasite_prep_ctl(pid_t pid)
-{
-	struct parasite_ctl *ctl = NULL;
-
-	/*
-	 * Control block early setup.
-	 */
-	ctl = xzalloc(sizeof(*ctl));
-	if (!ctl) {
-		pr_err("Parasite control block allocation failed (pid: %d)\n", pid);
-		goto err;
-	}
-
-	ctl->tsock = -1;
-
-	if (get_thread_ctx(pid, &ctl->orig))
-		goto err;
-
-	ctl->rpid = pid;
-
-	BUILD_BUG_ON(PARASITE_START_AREA_MIN < BUILTIN_SYSCALL_SIZE + MEMFD_FNAME_SZ);
-
-	return ctl;
-
-err:
-	xfree(ctl);
-	return NULL;
-}
-
 static int parasite_mmap_exchange(struct parasite_ctl *ctl, unsigned long size)
 {
 	int fd;
@@ -1266,7 +1221,7 @@ struct parasite_ctl *parasite_infect_seized(pid_t pid, struct pstree_item *item,
 		return NULL;
 	}
 
-	ctl = parasite_prep_ctl(pid);
+	ctl = compel_prepare(pid);
 	if (!ctl)
 		return NULL;