[PATCH v20210601 18/38] tools/guest: restore: move pfns array

[Olaf Hering <olaf@xxxxxxxxx>]

Remove allocation from hotpath, move pfns array into preallocated space.

Signed-off-by: Olaf Hering <olaf@xxxxxxxxx>
---
 tools/libs/saverestore/common.h  | 2 ++
 tools/libs/saverestore/restore.c | 6 ++----
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/tools/libs/saverestore/common.h b/tools/libs/saverestore/common.h
index 0e03b0731c..be6f98af7f 100644
--- a/tools/libs/saverestore/common.h
+++ b/tools/libs/saverestore/common.h
@@ -236,6 +236,8 @@ struct xc_sr_save_arrays {
 };
 
 struct xc_sr_restore_arrays {
+    /* handle_page_data */
+    xen_pfn_t pfns[MAX_BATCH_SIZE];
 };
 
 struct xc_sr_context
diff --git a/tools/libs/saverestore/restore.c b/tools/libs/saverestore/restore.c
index a6cf9ee41c..4d8ee19adf 100644
--- a/tools/libs/saverestore/restore.c
+++ b/tools/libs/saverestore/restore.c
@@ -315,7 +315,7 @@ static int handle_page_data(struct xc_sr_context *ctx, 
struct xc_sr_record *rec)
     unsigned int i, pages_of_data = 0;
     int rc = -1;
 
-    xen_pfn_t *pfns = NULL, pfn;
+    xen_pfn_t *pfns = ctx->restore.m->pfns, pfn;
     uint32_t *types = NULL, type;
 
     /*
@@ -363,9 +363,8 @@ static int handle_page_data(struct xc_sr_context *ctx, 
struct xc_sr_record *rec)
         goto err;
     }
 
-    pfns = malloc(pages->count * sizeof(*pfns));
     types = malloc(pages->count * sizeof(*types));
-    if ( !pfns || !types )
+    if ( !types )
     {
         ERROR("Unable to allocate enough memory for %u pfns",
               pages->count);
@@ -412,7 +411,6 @@ static int handle_page_data(struct xc_sr_context *ctx, 
struct xc_sr_record *rec)
                            &pages->pfn[pages->count]);
  err:
     free(types);
-    free(pfns);
 
     return rc;
 }