target/s390x/arch_dump: Simplify memory allocation in s390x_write_elf64_notes()

We are not on a hot path here, so there is no real need for the logic
here with the split heap and stack space allocation. Simplify it by
always allocating memory from the heap.

Suggested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230215085703.746788-1-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

diff --git a/target/s390x/arch_dump.c b/target/s390x/arch_dump.c
index a7c44ba49d317236c75446d1f1a51f4d75d2eac2..cb98f4894da93b3823c302b42ab2b176f542c224 100644 (file)
--- a/target/s390x/arch_dump.c
+++ b/target/s390x/arch_dump.c
@@ -227,25 +227,25 @@ static int s390x_write_elf64_notes(const char *note_name,
                                        DumpState *s,
                                        const NoteFuncDesc *funcs)
 {
-    Note note, *notep;
+    g_autofree Note *notep = NULL;
     const NoteFuncDesc *nf;
-    int note_size, content_size;
+    int note_size, prev_size = 0, content_size;
     int ret = -1;
 
-    assert(strlen(note_name) < sizeof(note.name));
+    assert(strlen(note_name) < sizeof(notep->name));
 
     for (nf = funcs; nf->note_contents_func; nf++) {
-        notep = &note;
         if (nf->pvonly && !s390_is_pv()) {
             continue;
         }
 
         content_size = nf->note_size_func ? nf->note_size_func() : nf->contents_size;
-        note_size = sizeof(note) - sizeof(notep->contents) + content_size;
+        note_size = sizeof(Note) - sizeof(notep->contents) + content_size;
 
-        /* Notes with dynamic sizes need to allocate a note */
-        if (nf->note_size_func) {
+        if (prev_size < note_size) {
+            g_free(notep);
             notep = g_malloc(note_size);
+            prev_size = note_size;
         }
 
         memset(notep, 0, note_size);
@@ -258,15 +258,9 @@ static int s390x_write_elf64_notes(const char *note_name,
         /* Get contents and write them out */
         (*nf->note_contents_func)(notep, cpu, id);
         ret = f(notep, note_size, s);
-
-        if (nf->note_size_func) {
-            g_free(notep);
-        }
-
         if (ret < 0) {
             return -1;
         }
-
     }
 
     return 0;