batman-adv uses a self-written reference implementation which is just based on atomic_t. This is less obvious when reading the code than kref and therefore increases the change that the reference counting will be missed.
Signed-off-by: Sven Eckelmann sven@narfation.org --- v6: - removed patches which are now applied in the branch next - rebased remaining patches on the patch "batman-adv: Avoid recursive call_rcu for batadv_nc_node" which was modified by Marek while he applied the patches (this unfortunately made some of the remaining patches "hard" to apply) v5: - add hack which allows to compile against stable kernel like 3.2.44 which also added the kref_get_unless_zero function v4: - fix function names in commit messages - fix double whitespace in batadv_tt_orig_list_entry_release kerneldoc - add extra patch for batadv_claim_free_ref kerneldoc fix - change the phrase "free it" in all *_free_ref/*_put functions to "release it" v3: - update copyright year v2: - split patchset into fixes and kref migration to make it easier when the decision is made where each patch will be applied
net/batman-adv/bridge_loop_avoidance.c | 16 ++++++++++------ net/batman-adv/types.h | 2 +- 2 files changed, 11 insertions(+), 7 deletions(-)
diff --git a/net/batman-adv/bridge_loop_avoidance.c b/net/batman-adv/bridge_loop_avoidance.c index 0937097..7781f39 100644 --- a/net/batman-adv/bridge_loop_avoidance.c +++ b/net/batman-adv/bridge_loop_avoidance.c @@ -172,10 +172,14 @@ batadv_backbone_gw_free_ref(struct batadv_bla_backbone_gw *backbone_gw) /** * batadv_claim_release - release claim from lists and queue for free after rcu * grace period - * @claim: claim to be free'd + * @ref: kref pointer of the claim */ -static void batadv_claim_release(struct batadv_bla_claim *claim) +static void batadv_claim_release(struct kref *ref) { + struct batadv_bla_claim *claim; + + claim = container_of(ref, struct batadv_bla_claim, refcount); + batadv_backbone_gw_free_ref(claim->backbone_gw); kfree_rcu(claim, rcu); } @@ -187,8 +191,7 @@ static void batadv_claim_release(struct batadv_bla_claim *claim) */ static void batadv_claim_free_ref(struct batadv_bla_claim *claim) { - if (atomic_dec_and_test(&claim->refcount)) - batadv_claim_release(claim); + kref_put(&claim->refcount, batadv_claim_release); }
/** @@ -219,7 +222,7 @@ static struct batadv_bla_claim if (!batadv_compare_claim(&claim->hash_entry, data)) continue;
- if (!atomic_inc_not_zero(&claim->refcount)) + if (!kref_get_unless_zero(&claim->refcount)) continue;
claim_tmp = claim; @@ -651,7 +654,8 @@ static void batadv_bla_add_claim(struct batadv_priv *bat_priv, claim->lasttime = jiffies; claim->backbone_gw = backbone_gw;
- atomic_set(&claim->refcount, 2); + kref_init(&claim->refcount); + kref_get(&claim->refcount); batadv_dbg(BATADV_DBG_BLA, bat_priv, "bla_add_claim(): adding new entry %pM, vid %d to hash ...\n", mac, BATADV_PRINT_VID(vid)); diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h index 595f524..34c13b6 100644 --- a/net/batman-adv/types.h +++ b/net/batman-adv/types.h @@ -951,7 +951,7 @@ struct batadv_bla_claim { unsigned long lasttime; struct hlist_node hash_entry; struct rcu_head rcu; - atomic_t refcount; + struct kref refcount; }; #endif