[v1,20/23] tools/guest: restore: move pfns array in populate_pfns

Commit Message

Olaf Hering Oct. 29, 2020, 5:20 p.m. UTC

Remove allocation from hotpath, move populate_pfns' pfns array into preallocated space.
Use some prefix to avoid conflict with an array used in handle_page_data.

Signed-off-by: Olaf Hering <[e-mail]>
---
 tools/libs/guest/xg_sr_common.h  |  1 +
 tools/libs/guest/xg_sr_restore.c | 11 +----------
 2 files changed, 2 insertions(+), 10 deletions(-)

Patch

diff --git a/tools/libs/guest/xg_sr_common.h b/tools/libs/guest/xg_sr_common.h
index 96a77b5969..3fe665b91d 100644
--- a/tools/libs/guest/xg_sr_common.h
+++ b/tools/libs/guest/xg_sr_common.h
@@ -232,6 +232,7 @@  struct xc_sr_restore_arrays {
     int map_errs[MAX_BATCH_SIZE];
     /* populate_pfns */
     xen_pfn_t pp_mfns[MAX_BATCH_SIZE];
+    xen_pfn_t pp_pfns[MAX_BATCH_SIZE];
 };
 
 struct xc_sr_context
diff --git a/tools/libs/guest/xg_sr_restore.c b/tools/libs/guest/xg_sr_restore.c
index 85a32aaed2..71b39612ee 100644
--- a/tools/libs/guest/xg_sr_restore.c
+++ b/tools/libs/guest/xg_sr_restore.c
@@ -139,17 +139,10 @@  int populate_pfns(struct xc_sr_context *ctx, unsigned int count,
 {
     xc_interface *xch = ctx->xch;
     xen_pfn_t *mfns = ctx->restore.m->pp_mfns,
-        *pfns = malloc(count * sizeof(*pfns));
+        *pfns = ctx->restore.m->pp_pfns;
     unsigned int i, nr_pfns = 0;
     int rc = -1;
 
-    if ( !pfns )
-    {
-        ERROR("Failed to allocate %zu bytes for populating the physmap",
-              2 * count * sizeof(*mfns));
-        goto err;
-    }
-
     for ( i = 0; i < count; ++i )
     {
         if ( (!types ||
@@ -190,8 +183,6 @@  int populate_pfns(struct xc_sr_context *ctx, unsigned int count,
     rc = 0;
 
  err:
-    free(pfns);
-
     return rc;
 }