/* Detect specific Linux Kernel features that we may use */
int mk_kernel_features()
{
int flags = 0;
/*
* FIXME: TCP Auto Corking:
*
* I found that running some benchmarks on Linux 3.16 with
* tcp_autocorking enabled, it lead to lower performance, looks like
* a manual cork fits better for our needs.
*
* I think there is something wrong that we need to clarify, by now
* I've logged the following issue:
*
* https://github.com/monkey/monkey/issues/175
*
if (mk_kernel_runver >= MK_KERNEL_VERSION(3, 14, 0) &&
mk_socket_tcp_autocorking() == MK_TRUE) {
flags |= MK_KERNEL_TCP_AUTOCORKING;
}
*/
/* SO_REUSEPORT */
if (mk_kernel_runver >= MK_KERNEL_VERSION(3, 9, 0)) {
flags |= MK_KERNEL_SO_REUSEPORT;
}
/* TCP_FASTOPEN */
if (mk_kernel_runver >= MK_KERNEL_VERSION(3, 7, 0)) {
flags |= MK_KERNEL_TCP_FASTOPEN;
}
config->kernel_features = flags;
return flags;
}
/*
* Enable the TCP_FASTOPEN feature for server side implemented in
* Linux Kernel >= 3.7, for more details read here:
*
* TCP Fast Open: expediting web services: http://lwn.net/Articles/508865/
*/
int mk_socket_set_tcp_fastopen(int sockfd)
{
#if defined (__linux__)
int qlen = 5;
if (mk_kernel_runver >= MK_KERNEL_VERSION(3, 7, 0)) {
return setsockopt(sockfd, SOL_TCP, TCP_FASTOPEN, &qlen, sizeof(qlen));
}
#endif
(void) sockfd;
return -1;
}
int mk_kernel_version()
{
int a, b, c;
int len;
int pos;
char *p, *t;
char *tmp;
struct utsname uts;
if (uname(&uts) == -1) {
mk_libc_error("uname");
}
len = strlen(uts.release);
/* Fixme: this don't support Linux Kernel 10.x.x :P */
a = (*uts.release - '0');
/* Second number */
p = (uts.release) + 2;
pos = mk_string_char_search(p, '.', len - 2);
if (pos <= 0) {
/* Some Debian systems uses a different notation, e.g: 3.14-2-amd64 */
pos = mk_string_char_search(p, '-', len - 2);
if (pos <= 0) {
return -1;
}
}
tmp = mk_string_copy_substr(p, 0, pos);
if (!tmp) {
return -1;
}
b = atoi(tmp);
mk_mem_free(tmp);
/* Last number (it needs filtering) */
t = p = p + pos + 1;
do {
t++;
} while (isdigit(*t));
tmp = mk_string_copy_substr(p, 0, t - p);
if (!tmp) {
return -1;
}
c = atoi(tmp);
mk_mem_free(tmp);
MK_TRACE("Kernel detected: %i.%i.%i", a, b, c);
return MK_KERNEL_VERSION(a, b, c);
}
