From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934375AbcI3V35 (ORCPT ); Fri, 30 Sep 2016 17:29:57 -0400 Received: from g2t1383g.austin.hpe.com ([15.233.16.89]:54296 "EHLO g2t1383g.austin.hpe.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933560AbcI3V1r (ORCPT ); Fri, 30 Sep 2016 17:27:47 -0400 From: Waiman Long To: Thomas Gleixner , Ingo Molnar , Peter Zijlstra , Jonathan Corbet Cc: linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, Arnaldo Carvalho de Melo , Davidlohr Bueso , Mike Galbraith , Jason Low , Scott J Norton , Douglas Hatch , Waiman Long Subject: [PATCH v3 05/13] futex: Add a new futex type field into futex_state Date: Fri, 30 Sep 2016 17:26:14 -0400 Message-Id: <1475270782-51720-6-git-send-email-Waiman.Long@hpe.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1475270782-51720-1-git-send-email-Waiman.Long@hpe.com> References: <1475270782-51720-1-git-send-email-Waiman.Long@hpe.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org As the futex_state structure will be overloaded in later patches to be used by non-PI futexes, it is necessary to add a type field to distinguish among different types of futexes. Signed-off-by: Waiman Long --- kernel/futex.c | 14 ++++++++++---- 1 files changed, 10 insertions(+), 4 deletions(-) diff --git a/kernel/futex.c b/kernel/futex.c index 0d1b1be..a496c01 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -191,6 +191,10 @@ int __read_mostly futex_cmpxchg_enabled; #define FLAGS_CLOCKRT 0x02 #define FLAGS_HAS_TIMEOUT 0x04 +enum futex_type { + TYPE_PI = 0, +}; + /* * Futex state object: * - Priority Inheritance state @@ -210,6 +214,7 @@ struct futex_state { struct task_struct *owner; atomic_t refcount; + enum futex_type type; union futex_key key; }; @@ -897,10 +902,10 @@ static void put_futex_state(struct futex_state *state) return; /* - * If state->owner is NULL, the owner is most probably dying - * and has cleaned up the futex state already + * If state->owner is NULL and the type is TYPE_PI, the owner is + * most probably dying and has cleaned up the futex state already */ - if (state->owner) { + if (state->owner && (state->type == TYPE_PI)) { task_pi_list_del(state->owner, state, false); rt_mutex_proxy_unlock(&state->pi_mutex, state->owner); @@ -1056,7 +1061,7 @@ static int attach_to_pi_state(u32 uval, struct futex_state *pi_state, /* * Userspace might have messed up non-PI and PI futexes [3] */ - if (unlikely(!pi_state)) + if (unlikely(!pi_state || (pi_state->type != TYPE_PI))) return -EINVAL; WARN_ON(!atomic_read(&pi_state->refcount)); @@ -1174,6 +1179,7 @@ static int attach_to_pi_owner(u32 uval, union futex_key *key, /* Store the key for possible exit cleanups: */ pi_state->key = *key; + pi_state->type = TYPE_PI; WARN_ON(!list_empty(&pi_state->list)); list_add(&pi_state->list, &p->pi_state_list); -- 1.7.1