af_unix: Bulk update unix_tot_inflight/unix_inflight when queuing skb.

Currently, we track the number of inflight sockets in two variables.
unix_tot_inflight is the total number of inflight AF_UNIX sockets on
the host, and user->unix_inflight is the number of inflight fds per
user.

We update them one by one in unix_inflight(), which can be done once
in batch.  Also, sendmsg() could fail even after unix_inflight(), then
we need to acquire unix_gc_lock only to decrement the counters.

Let's bulk update the counters in unix_add_edges() and unix_del_edges(),
which is called only for successfully passed fds.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20240325202425.60930-5-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Kuniyuki Iwashima 2024-03-25 13:24:14 -07:00 committed by Jakub Kicinski
parent 42f298c06b
commit 22c3c0c52d

View File

@ -144,6 +144,7 @@ static void unix_free_vertices(struct scm_fp_list *fpl)
}
DEFINE_SPINLOCK(unix_gc_lock);
unsigned int unix_tot_inflight;
void unix_add_edges(struct scm_fp_list *fpl, struct unix_sock *receiver)
{
@ -168,7 +169,10 @@ void unix_add_edges(struct scm_fp_list *fpl, struct unix_sock *receiver)
unix_add_edge(fpl, edge);
} while (i < fpl->count_unix);
WRITE_ONCE(unix_tot_inflight, unix_tot_inflight + fpl->count_unix);
out:
WRITE_ONCE(fpl->user->unix_inflight, fpl->user->unix_inflight + fpl->count);
spin_unlock(&unix_gc_lock);
fpl->inflight = true;
@ -191,7 +195,10 @@ void unix_del_edges(struct scm_fp_list *fpl)
unix_del_edge(fpl, edge);
} while (i < fpl->count_unix);
WRITE_ONCE(unix_tot_inflight, unix_tot_inflight - fpl->count_unix);
out:
WRITE_ONCE(fpl->user->unix_inflight, fpl->user->unix_inflight - fpl->count);
spin_unlock(&unix_gc_lock);
fpl->inflight = false;
@ -234,7 +241,6 @@ void unix_destroy_fpl(struct scm_fp_list *fpl)
unix_free_vertices(fpl);
}
unsigned int unix_tot_inflight;
static LIST_HEAD(gc_candidates);
static LIST_HEAD(gc_inflight_list);
@ -255,13 +261,8 @@ void unix_inflight(struct user_struct *user, struct file *filp)
WARN_ON_ONCE(list_empty(&u->link));
}
u->inflight++;
/* Paired with READ_ONCE() in wait_for_unix_gc() */
WRITE_ONCE(unix_tot_inflight, unix_tot_inflight + 1);
}
WRITE_ONCE(user->unix_inflight, user->unix_inflight + 1);
spin_unlock(&unix_gc_lock);
}
@ -278,13 +279,8 @@ void unix_notinflight(struct user_struct *user, struct file *filp)
u->inflight--;
if (!u->inflight)
list_del_init(&u->link);
/* Paired with READ_ONCE() in wait_for_unix_gc() */
WRITE_ONCE(unix_tot_inflight, unix_tot_inflight - 1);
}
WRITE_ONCE(user->unix_inflight, user->unix_inflight - 1);
spin_unlock(&unix_gc_lock);
}