get page_size dynamically from sysconf

src/aarch64/Ginit.c

@@ -25,10 +25,11 @@ OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */
 
 #include <errno.h>
+#include <stdatomic.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/mman.h>
-#include <stdatomic.h>
+#include <unistd.h>
 
 #include "unwind_i.h"
 
@@ -84,9 +85,9 @@ get_dyn_info_list_addr (unw_addr_space_t as, unw_word_t *dyn_info_list_addr,
   return 0;
 }
 
-#define PAGE_SIZE 4096
-#define PAGE_START(a)   ((a) & ~(PAGE_SIZE-1))
+#define PAGE_START(addr, page_size) ((addr) & ~(page_size - 1))
 
+static int mem_page_size;
 static int mem_validate_pipe[2] = {-1, -1};
 
 #ifdef HAVE_PIPE2
@@ -194,13 +195,14 @@ HIDDEN void
 tdep_init_mem_validate (void)
 {
   open_pipe ();
+  mem_page_size = sysconf(_SC_PAGESIZE);
 
 #ifdef HAVE_MINCORE
   unsigned char present = 1;
-  unw_word_t addr = PAGE_START((unw_word_t)&present);
+  unw_word_t addr = PAGE_START((unw_word_t)&present, mem_page_size);
   unsigned char mvec[1];
   int ret;
-  while ((ret = mincore ((void*)addr, PAGE_SIZE, (unsigned char *)mvec)) == -1 &&
+  while ((ret = mincore((void*)addr, mem_page_size, (unsigned char*)mvec)) == -1 &&
          errno == EAGAIN) {}
   if (ret == 0)
     {
@@ -295,12 +297,9 @@ validate_mem (unw_word_t addr)
 {
   size_t len;
 
-  if (PAGE_START(addr + sizeof (unw_word_t) - 1) == PAGE_START(addr))
-    len = PAGE_SIZE;
-  else
-    len = PAGE_SIZE * 2;
 
-  addr = PAGE_START(addr);
+  len = mem_page_size;
+  addr = PAGE_START(addr, mem_page_size);
 
   if (addr == 0)
     return -1;