Commit 53910ef7 authored by Zhen Lei's avatar Zhen Lei Committed by Jiri Kosina

livepatch: Move the result-invariant calculation out of the loop

The calculation results of the variables 'func_addr' and 'func_size' are
not affected by the for loop and do not change due to the changes of
entries[i]. The performance can be improved by moving it outside the loop.

No functional change.
Signed-off-by: default avatarZhen Lei <thunder.leizhen@huawei.com>
Reviewed-by: default avatarPetr Mladek <pmladek@suse.com>
Signed-off-by: default avatarJiri Kosina <jkosina@suse.cz>
parent 4de65c58
......@@ -196,36 +196,36 @@ static int klp_check_stack_func(struct klp_func *func, unsigned long *entries,
struct klp_ops *ops;
int i;
for (i = 0; i < nr_entries; i++) {
address = entries[i];
if (klp_target_state == KLP_UNPATCHED) {
/*
* Check for the to-be-unpatched function
* (the func itself).
*/
func_addr = (unsigned long)func->new_func;
func_size = func->new_size;
} else {
/*
* Check for the to-be-patched function
* (the previous func).
*/
ops = klp_find_ops(func->old_func);
if (klp_target_state == KLP_UNPATCHED) {
/*
* Check for the to-be-unpatched function
* (the func itself).
*/
func_addr = (unsigned long)func->new_func;
func_size = func->new_size;
if (list_is_singular(&ops->func_stack)) {
/* original function */
func_addr = (unsigned long)func->old_func;
func_size = func->old_size;
} else {
/*
* Check for the to-be-patched function
* (the previous func).
*/
ops = klp_find_ops(func->old_func);
if (list_is_singular(&ops->func_stack)) {
/* original function */
func_addr = (unsigned long)func->old_func;
func_size = func->old_size;
} else {
/* previously patched function */
struct klp_func *prev;
prev = list_next_entry(func, stack_node);
func_addr = (unsigned long)prev->new_func;
func_size = prev->new_size;
}
/* previously patched function */
struct klp_func *prev;
prev = list_next_entry(func, stack_node);
func_addr = (unsigned long)prev->new_func;
func_size = prev->new_size;
}
}
for (i = 0; i < nr_entries; i++) {
address = entries[i];
if (address >= func_addr && address < func_addr + func_size)
return -EAGAIN;
......
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