[CRIU] [PATCH 08/10] vdso: move VMAs traverse cycle in vdso_proxify()

[Dmitry Safonov]

Reduce __export_restore_task(), which is fat and too long,
drop needless parameter from vdso_proxify() and drop also
that find-tuple logic, which isn't needed really.

Signed-off-by: Dmitry Safonov <dsafonov at virtuozzo.com>
---
 criu/include/parasite-vdso.h |  2 +-
 criu/pie/parasite-vdso.c     | 31 +++++++++++++++++--------------
 criu/pie/restorer.c          | 18 ++++--------------
 3 files changed, 22 insertions(+), 29 deletions(-)

diff --git a/criu/include/parasite-vdso.h b/criu/include/parasite-vdso.h
index 8f7aaf9e0fd2..11a4135e053e 100644
--- a/criu/include/parasite-vdso.h
+++ b/criu/include/parasite-vdso.h
@@ -82,7 +82,7 @@ static inline bool is_vdso_mark(void *addr)
 extern int vdso_do_park(struct vdso_symtable *sym_rt, unsigned long park_at, unsigned long park_size);
 extern int vdso_map_compat(unsigned long map_at);
 extern int vdso_proxify(struct vdso_symtable *sym_rt,
-			unsigned long vdso_rt_parked_at, size_t index,
+			unsigned long vdso_rt_parked_at,
 			VmaEntry *vmas, size_t nr_vmas, bool compat_vdso);
 
 #else /* CONFIG_VDSO */
diff --git a/criu/pie/parasite-vdso.c b/criu/pie/parasite-vdso.c
index e55c23a0734e..dc4d033764d6 100644
--- a/criu/pie/parasite-vdso.c
+++ b/criu/pie/parasite-vdso.c
@@ -104,26 +104,29 @@ int __vdso_fill_symtable(uintptr_t mem, size_t size,
 #endif
 
 int vdso_proxify(struct vdso_symtable *sym_rt,
-		 unsigned long vdso_rt_parked_at, size_t index,
+		 unsigned long vdso_rt_parked_at,
 		 VmaEntry *vmas, size_t nr_vmas, bool compat_vdso)
 {
 	VmaEntry *vma_vdso = NULL, *vma_vvar = NULL;
 	struct vdso_symtable s = VDSO_SYMTABLE_INIT;
 	bool remap_rt = false;
+	unsigned int i;
 
-	/*
-	 * Figure out which kind of vdso tuple we get.
-	 */
-	if (vma_entry_is(&vmas[index], VMA_AREA_VDSO))
-		vma_vdso = &vmas[index];
-	else if (vma_entry_is(&vmas[index], VMA_AREA_VVAR))
-		vma_vvar = &vmas[index];
-
-	if (index < (nr_vmas - 1)) {
-		if (vma_entry_is(&vmas[index + 1], VMA_AREA_VDSO))
-			vma_vdso = &vmas[index + 1];
-		else if (vma_entry_is(&vmas[index + 1], VMA_AREA_VVAR))
-			vma_vvar = &vmas[index + 1];
+	for (i = 0; i < nr_vmas; i++) {
+		if (vma_entry_is(&vmas[i], VMA_AREA_VDSO))
+			vma_vdso = &vmas[i];
+		else if (vma_entry_is(&vmas[i], VMA_AREA_VVAR))
+			vma_vvar = &vmas[i];
+	}
+
+	if (!vma_vdso && !vma_vvar) {
+		pr_info("No VVAR, no vDSO in image\n");
+		/*
+		 * We don't have to unmap rt-vdso, rt-vvar as they will
+		 * be unmapped with restorer blob in the end,
+		 * see __export_unmap()
+		 */
+		return 0;
 	}
 
 	if (!vma_vdso) {
diff --git a/criu/pie/restorer.c b/criu/pie/restorer.c
index 4bea30293575..7783ce2f16e9 100644
--- a/criu/pie/restorer.c
+++ b/criu/pie/restorer.c
@@ -1250,23 +1250,13 @@ long __export_restore_task(struct task_restore_args *args)
 	}
 
 #ifdef CONFIG_VDSO
-	if (args->check_only)
-		goto skip_vdso;
 	/*
 	 * Proxify vDSO.
 	 */
-	for (i = 0; i < args->vmas_n; i++) {
-		if (vma_entry_is(&args->vmas[i], VMA_AREA_VDSO) ||
-		    vma_entry_is(&args->vmas[i], VMA_AREA_VVAR)) {
-			if (vdso_proxify(&args->vdso_sym_rt,
-					 args->vdso_rt_parked_at,
-					 i, args->vmas, args->vmas_n,
-					 args->compatible_mode))
-				goto core_restore_end;
-			break;
-		}
-	}
-skip_vdso:
+	if (!args->check_only)
+		if (vdso_proxify(&args->vdso_sym_rt, args->vdso_rt_parked_at,
+			     args->vmas, args->vmas_n, args->compatible_mode))
+			goto core_restore_end;
 #endif
 
 	/*
-- 
2.11.1