libbb: add and use infrastructure for fixed page size optimization

function                                             old     new   delta
procps_scan                                         1121    1118      -3
getpagesize                                            6       -      -6
rpm_main                                            1037    1027     -10
rpm2cpio_main                                        120     110     -10
ptok                                                  38      21     -17
time_main                                           1282    1261     -21
mkswap_main                                          317     278     -39
------------------------------------------------------------------------------
(add/remove: 0/2 grow/shrink: 0/6 up/down: 0/-106)           Total: -106 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 3 insertions, 11 deletions

diff --git a/miscutils/hexedit.c b/miscutils/hexedit.c
index 898d77376..f8ff9b62b 100644
--- a/miscutils/hexedit.c
+++ b/miscutils/hexedit.c
@@ -31,7 +31,8 @@ struct globals {
         int fd;
         unsigned height;
         unsigned row;
-        unsigned pagesize;
+        IF_VARIABLE_ARCH_PAGESIZE(unsigned pagesize;)
+#define G_pagesize cached_pagesize(G.pagesize)
         uint8_t *baseaddr;
         uint8_t *current_byte;
         uint8_t *eof_byte;
@@ -46,15 +47,6 @@ struct globals {
         SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
 } while (0)
 
-//TODO: move to libbb
-#if defined(__x86_64__) || defined(i386)
-# define G_pagesize 4096
-# define INIT_PAGESIZE() ((void)0)
-#else
-# define G_pagesize (G.pagesize)
-# define INIT_PAGESIZE() ((void)(G.pagesize = getpagesize()))
-#endif
-
 /* hopefully there aren't arches with PAGE_SIZE > 64k */
 #define G_mapsize  (64*1024)
 
@@ -262,7 +254,7 @@ int hexedit_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int hexedit_main(int argc UNUSED_PARAM, char **argv)
 {
         INIT_G();
-        INIT_PAGESIZE();
+        INIT_PAGESIZE(G.pagesize);
 
         get_terminal_width_height(-1, NULL, &G.height);
         if (1) {