Modify the net.inet.tcp.function_ids sysctl introduced in r331347.

Export additional information which may be helpful to userspace
consumers and rename the sysctl to net.inet.tcp.function_info.

Sponsored by:	Netflix, Inc.
This commit is contained in:
jtl 2018-04-10 16:59:36 +00:00
parent 61b590a78c
commit 32f06b2ce4

View File

@ -255,6 +255,7 @@ static struct tcp_function_block tcp_def_funcblk = {
};
int t_functions_inited = 0;
static int tcp_fb_cnt = 0;
struct tcp_funchead t_functions;
static struct tcp_function_block *tcp_func_set_ptr = &tcp_def_funcblk;
@ -426,14 +427,14 @@ SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_available,
"list available TCP Function sets");
/*
* Exports one (struct tcp_function_id) for each non-alias.
* Exports one (struct tcp_function_info) for each alias/name.
*/
static int
sysctl_net_inet_list_func_ids(SYSCTL_HANDLER_ARGS)
sysctl_net_inet_list_func_info(SYSCTL_HANDLER_ARGS)
{
int error, cnt;
int cnt, error;
struct tcp_function *f;
struct tcp_function_id tfi;
struct tcp_function_info tfi;
/*
* We don't allow writes.
@ -452,20 +453,31 @@ sysctl_net_inet_list_func_ids(SYSCTL_HANDLER_ARGS)
}
/*
* Walk the list, comparing the name of the function entry and
* function block to determine which is an alias.
* If exporting the list, copy out matching entries. Otherwise,
* just record the total length.
* Walk the list and copy out matching entries. If INVARIANTS
* is compiled in, also walk the list to verify the length of
* the list matches what we have recorded.
*/
cnt = 0;
rw_rlock(&tcp_function_lock);
#ifdef INVARIANTS
cnt = 0;
#else
if (req->oldptr == NULL) {
cnt = tcp_fb_cnt;
goto skip_loop;
}
#endif
TAILQ_FOREACH(f, &t_functions, tf_next) {
if (strncmp(f->tf_name, f->tf_fb->tfb_tcp_block_name,
TCP_FUNCTION_NAME_LEN_MAX))
continue;
#ifdef INVARIANTS
cnt++;
#endif
if (req->oldptr != NULL) {
tfi.tfi_refcnt = f->tf_fb->tfb_refcnt;
tfi.tfi_id = f->tf_fb->tfb_id;
(void)strncpy(tfi.tfi_name, f->tf_name,
(void)strncpy(tfi.tfi_alias, f->tf_name,
TCP_FUNCTION_NAME_LEN_MAX);
tfi.tfi_alias[TCP_FUNCTION_NAME_LEN_MAX - 1] = '\0';
(void)strncpy(tfi.tfi_name,
f->tf_fb->tfb_tcp_block_name,
TCP_FUNCTION_NAME_LEN_MAX);
tfi.tfi_name[TCP_FUNCTION_NAME_LEN_MAX - 1] = '\0';
error = SYSCTL_OUT(req, &tfi, sizeof(tfi));
@ -474,20 +486,24 @@ sysctl_net_inet_list_func_ids(SYSCTL_HANDLER_ARGS)
* mechanism we use to accumulate length
* information if the buffer was too short.
*/
} else
cnt++;
}
}
KASSERT(cnt == tcp_fb_cnt,
("%s: cnt (%d) != tcp_fb_cnt (%d)", __func__, cnt, tcp_fb_cnt));
#ifndef INVARIANTS
skip_loop:
#endif
rw_runlock(&tcp_function_lock);
if (req->oldptr == NULL)
error = SYSCTL_OUT(req, NULL,
(cnt + 1) * sizeof(struct tcp_function_id));
(cnt + 1) * sizeof(struct tcp_function_info));
return (error);
}
SYSCTL_PROC(_net_inet_tcp, OID_AUTO, function_ids,
SYSCTL_PROC(_net_inet_tcp, OID_AUTO, function_info,
CTLTYPE_OPAQUE | CTLFLAG_SKIP | CTLFLAG_RD | CTLFLAG_MPSAFE,
NULL, 0, sysctl_net_inet_list_func_ids, "S,tcp_function_id",
NULL, 0, sysctl_net_inet_list_func_info, "S,tcp_function_info",
"List TCP function block name-to-ID mappings");
/*
@ -653,6 +669,7 @@ register_tcp_functions_as_names(struct tcp_function_block *blk, int wait,
(void)strncpy(n->tf_name, names[i], TCP_FUNCTION_NAME_LEN_MAX);
n->tf_name[TCP_FUNCTION_NAME_LEN_MAX - 1] = '\0';
TAILQ_INSERT_TAIL(&t_functions, n, tf_next);
tcp_fb_cnt++;
rw_wunlock(&tcp_function_lock);
}
return(0);
@ -669,6 +686,7 @@ register_tcp_functions_as_names(struct tcp_function_block *blk, int wait,
if (!strncmp(n->tf_name, names[i],
TCP_FUNCTION_NAME_LEN_MAX)) {
TAILQ_REMOVE(&t_functions, n, tf_next);
tcp_fb_cnt--;
n->tf_fb = NULL;
free(n, M_TCPFUNCTIONS);
break;
@ -739,6 +757,7 @@ deregister_tcp_functions(struct tcp_function_block *blk)
while (find_tcp_fb_locked(blk, &f) != NULL) {
/* Found */
TAILQ_REMOVE(&t_functions, f, tf_next);
tcp_fb_cnt--;
f->tf_fb = NULL;
free(f, M_TCPFUNCTIONS);
error = 0;