git: d09388d01330 - main - pf: add pf_release_staten and use it in pf_unlink_state

[Mateusz Guzik]

The branch main has been updated by mjg:

URL: https://cgit.FreeBSD.org/src/commit/?id=d09388d013300fc4aa1ee1a6bc24260cd400aff3

commit d09388d013300fc4aa1ee1a6bc24260cd400aff3
Author:     Mateusz Guzik <mjg at FreeBSD.org>
AuthorDate: 2021-06-28 12:18:43 +0000
Commit:     Mateusz Guzik <mjg at FreeBSD.org>
CommitDate: 2021-06-28 15:49:20 +0000

    pf: add pf_release_staten and use it in pf_unlink_state
    
    Saves one atomic op.
    
    Reviewed by:    kp
    Sponsored by:   Rubicon Communications, LLC ("Netgate")
---
 sys/net/pfvar.h     | 11 +++++++++++
 sys/netpfil/pf/pf.c |  7 ++-----
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/sys/net/pfvar.h b/sys/net/pfvar.h
index e07016f7b66c..9578ec0a701f 100644
--- a/sys/net/pfvar.h
+++ b/sys/net/pfvar.h
@@ -1510,6 +1510,17 @@ pf_release_state(struct pf_state *s)
 		return (0);
 }
 
+static __inline int
+pf_release_staten(struct pf_state *s, u_int n)
+{
+
+	if (refcount_releasen(&s->refs, n)) {
+		pf_free_state(s);
+		return (1);
+	} else
+		return (0);
+}
+
 extern struct pf_state		*pf_find_state_byid(uint64_t, uint32_t);
 extern struct pf_state		*pf_find_state_all(struct pf_state_key_cmp *,
 				    u_int, int *);
diff --git a/sys/netpfil/pf/pf.c b/sys/netpfil/pf/pf.c
index 7e187a358783..02d0809f738d 100644
--- a/sys/netpfil/pf/pf.c
+++ b/sys/netpfil/pf/pf.c
@@ -1732,11 +1732,8 @@ pf_unlink_state(struct pf_state *s, u_int flags)
 	PF_HASHROW_UNLOCK(ih);
 
 	pf_detach_state(s);
-	/* pf_state_insert() initialises refs to 2, so we can never release the
-	 * last reference here, only in pf_release_state(). */
-	(void)refcount_release(&s->refs);
-
-	return (pf_release_state(s));
+	/* pf_state_insert() initialises refs to 2 */
+	return (pf_release_staten(s, 2));
 }
 
 void