summaryrefslogtreecommitdiff
path: root/drivers/connector
diff options
context:
space:
mode:
authorAnjali Kulkarni <anjali.k.kulkarni@oracle.com>2023-07-19 13:18:19 -0700
committerDavid S. Miller <davem@davemloft.net>2023-07-23 11:34:22 +0100
commit743acf351bae1ff7ff4aaadd6a406d4d6091d90b (patch)
tree5f25faf64e85567493ed13529c490c4253742271 /drivers/connector
parent2aa1f7a1f47ce8dac7593af605aaa859b3cf3bb1 (diff)
connector/cn_proc: Performance improvements
This patch adds the capability to filter messages sent by the proc connector on the event type supplied in the message from the client to the connector. The client can register to listen for an event type given in struct proc_input. This event based filteting will greatly enhance performance - handling 8K exits takes about 70ms, whereas 8K-forks + 8K-exits takes about 150ms & handling 8K-forks + 8K-exits + 8K-execs takes 200ms. There are currently 9 different types of events, and we need to listen to all of them. Also, measuring the time using pidfds for monitoring 8K process exits took much longer - 200ms, as compared to 70ms using only exit notifications of proc connector. We also add a new event type - PROC_EVENT_NONZERO_EXIT, which is only sent by kernel to a listening application when any process exiting, has a non-zero exit status. This will help the clients like Oracle DB, where a monitoring process wants notfications for non-zero process exits so it can cleanup after them. This kind of a new event could also be useful to other applications like Google's lmkd daemon, which needs a killed process's exit notification. The patch takes care that existing clients using old mechanism of not sending the event type work without any changes. cn_filter function checks to see if the event type being notified via proc connector matches the event type requested by client, before sending(matches) or dropping(does not match) a packet. Signed-off-by: Anjali Kulkarni <anjali.k.kulkarni@oracle.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/connector')
-rw-r--r--drivers/connector/cn_proc.c62
1 files changed, 56 insertions, 6 deletions
diff --git a/drivers/connector/cn_proc.c b/drivers/connector/cn_proc.c
index 1ba288ed2bf7..dfc84d44f804 100644
--- a/drivers/connector/cn_proc.c
+++ b/drivers/connector/cn_proc.c
@@ -50,21 +50,45 @@ static DEFINE_PER_CPU(struct local_event, local_event) = {
static int cn_filter(struct sock *dsk, struct sk_buff *skb, void *data)
{
+ __u32 what, exit_code, *ptr;
enum proc_cn_mcast_op mc_op;
+ uintptr_t val;
- if (!dsk)
+ if (!dsk || !data)
return 0;
+ ptr = (__u32 *)data;
+ what = *ptr++;
+ exit_code = *ptr;
+ val = ((struct proc_input *)(dsk->sk_user_data))->event_type;
mc_op = ((struct proc_input *)(dsk->sk_user_data))->mcast_op;
if (mc_op == PROC_CN_MCAST_IGNORE)
return 1;
- return 0;
+ if ((__u32)val == PROC_EVENT_ALL)
+ return 0;
+
+ /*
+ * Drop packet if we have to report only non-zero exit status
+ * (PROC_EVENT_NONZERO_EXIT) and exit status is 0
+ */
+ if (((__u32)val & PROC_EVENT_NONZERO_EXIT) &&
+ (what == PROC_EVENT_EXIT)) {
+ if (exit_code)
+ return 0;
+ }
+
+ if ((__u32)val & what)
+ return 0;
+
+ return 1;
}
static inline void send_msg(struct cn_msg *msg)
{
+ __u32 filter_data[2];
+
local_lock(&local_event.lock);
msg->seq = __this_cpu_inc_return(local_event.count) - 1;
@@ -76,8 +100,16 @@ static inline void send_msg(struct cn_msg *msg)
*
* If cn_netlink_send() fails, the data is not sent.
*/
+ filter_data[0] = ((struct proc_event *)msg->data)->what;
+ if (filter_data[0] == PROC_EVENT_EXIT) {
+ filter_data[1] =
+ ((struct proc_event *)msg->data)->event_data.exit.exit_code;
+ } else {
+ filter_data[1] = 0;
+ }
+
cn_netlink_send_mult(msg, msg->len, 0, CN_IDX_PROC, GFP_NOWAIT,
- cn_filter, NULL);
+ cn_filter, (void *)filter_data);
local_unlock(&local_event.lock);
}
@@ -357,12 +389,15 @@ static void cn_proc_ack(int err, int rcvd_seq, int rcvd_ack)
/**
* cn_proc_mcast_ctl
- * @data: message sent from userspace via the connector
+ * @msg: message sent from userspace via the connector
+ * @nsp: NETLINK_CB of the client's socket buffer
*/
static void cn_proc_mcast_ctl(struct cn_msg *msg,
struct netlink_skb_parms *nsp)
{
enum proc_cn_mcast_op mc_op = 0, prev_mc_op = 0;
+ struct proc_input *pinput = NULL;
+ enum proc_cn_event ev_type = 0;
int err = 0, initial = 0;
struct sock *sk = NULL;
@@ -381,10 +416,21 @@ static void cn_proc_mcast_ctl(struct cn_msg *msg,
goto out;
}
- if (msg->len == sizeof(mc_op))
+ if (msg->len == sizeof(*pinput)) {
+ pinput = (struct proc_input *)msg->data;
+ mc_op = pinput->mcast_op;
+ ev_type = pinput->event_type;
+ } else if (msg->len == sizeof(mc_op)) {
mc_op = *((enum proc_cn_mcast_op *)msg->data);
- else
+ ev_type = PROC_EVENT_ALL;
+ } else {
return;
+ }
+
+ ev_type = valid_event((enum proc_cn_event)ev_type);
+
+ if (ev_type == PROC_EVENT_NONE)
+ ev_type = PROC_EVENT_ALL;
if (nsp->sk) {
sk = nsp->sk;
@@ -400,6 +446,8 @@ static void cn_proc_mcast_ctl(struct cn_msg *msg,
prev_mc_op =
((struct proc_input *)(sk->sk_user_data))->mcast_op;
}
+ ((struct proc_input *)(sk->sk_user_data))->event_type =
+ ev_type;
((struct proc_input *)(sk->sk_user_data))->mcast_op = mc_op;
}
@@ -411,6 +459,8 @@ static void cn_proc_mcast_ctl(struct cn_msg *msg,
case PROC_CN_MCAST_IGNORE:
if (!initial && (prev_mc_op != PROC_CN_MCAST_IGNORE))
atomic_dec(&proc_event_num_listeners);
+ ((struct proc_input *)(sk->sk_user_data))->event_type =
+ PROC_EVENT_NONE;
break;
default:
err = EINVAL;