common, env: optimize boottime
when creating the hashtable, for each environmentvariable
getenv(ENV_CALLBACK_VAR) and getenv(ENV_FLAGS_VAR) is called,
which costs at this point a lot of time. So call this two
getenv() calls only once.
Boottime on the ids8313 board without this patch:
2013-12-19 13:38:22,894: NAND: 128 MiB
2013-12-19 13:38:27,659: In: serial
(~4.8 sec)
Bootime with this patch on the ids8313 board:
2013-12-19 13:40:25,332: NAND: 128 MiB
2013-12-19 13:40:25,546: In: serial
(~0.2 sec)
Signed-off-by: Heiko Schocher <hs@denx.de>
Cc: Tom Rini <trini@ti.com>
Cc: Joe Hershberger <joe.hershberger@ni.com>
Cc: Wolfgang Denk <wd@denx.de>
diff --git a/common/env_callback.c b/common/env_callback.c
index 34bb58e..d03fa03 100644
--- a/common/env_callback.c
+++ b/common/env_callback.c
@@ -35,6 +35,9 @@
return NULL;
}
+static int first_call = 1;
+static const char *callback_list;
+
/*
* Look for a possible callback for a newly added variable
* This is called specifically when the variable did not exist in the hash
@@ -43,11 +46,15 @@
void env_callback_init(ENTRY *var_entry)
{
const char *var_name = var_entry->key;
- const char *callback_list = getenv(ENV_CALLBACK_VAR);
char callback_name[256] = "";
struct env_clbk_tbl *clbkp;
int ret = 1;
+ if (first_call) {
+ callback_list = getenv(ENV_CALLBACK_VAR);
+ first_call = 0;
+ }
+
/* look in the ".callbacks" var for a reference to this variable */
if (callback_list != NULL)
ret = env_attr_lookup(callback_list, var_name, callback_name);