@@ -60,6 +60,7 @@ static unsigned int table_size, table_cnt;
static int all_symbols;
static int absolute_percpu;
static int base_relative;
+static int sym_start_idx;
static int token_profit[0x10000];
@@ -511,7 +512,7 @@ static void learn_symbol(const unsigned char *symbol, int len)
{
int i;
- for (i = 0; i < len - 1; i++)
+ for (i = sym_start_idx; i < len - 1; i++)
token_profit[ symbol[i] + (symbol[i + 1] << 8) ]++;
}
@@ -520,7 +521,7 @@ static void forget_symbol(const unsigned char *symbol, int len)
{
int i;
- for (i = 0; i < len - 1; i++)
+ for (i = sym_start_idx; i < len - 1; i++)
token_profit[ symbol[i] + (symbol[i + 1] << 8) ]--;
}
@@ -538,7 +539,7 @@ static unsigned char *find_token(unsigned char *str, int len,
{
int i;
- for (i = 0; i < len - 1; i++) {
+ for (i = sym_start_idx; i < len - 1; i++) {
if (str[i] == token[0] && str[i+1] == token[1])
return &str[i];
}
@@ -780,6 +781,14 @@ int main(int argc, char **argv)
} else if (argc != 1)
usage();
+ /*
+ * Skip the symbol type, do not compress it to optimize the performance
+ * of finding or traversing symbols in kernel, this is good for modules
+ * such as livepatch.
+ */
+ if (all_symbols)
+ sym_start_idx = 1;
+
read_map(stdin);
shrink_table();
if (absolute_percpu)
Currently, to search for a symbol, we need to expand the symbols in 'kallsyms_names' one by one, and then use the expanded string for comparison. This is very slow. In fact, we can first compress the name being looked up and then use it for comparison when traversing 'kallsyms_names'. This increases the size of 'kallsyms_names'. About 48KiB, 2.67%, on x86 with defconfig. Before: kallsyms_num_syms=131392, sizeof(kallsyms_names)=1823659 After : kallsyms_num_syms=131392, sizeof(kallsyms_names)=1872418 However, if CONFIG_KALLSYMS_ALL is not set, the size of 'kallsyms_names' does not change. Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> --- scripts/kallsyms.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-)