From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753331AbcL2QSB (ORCPT ); Thu, 29 Dec 2016 11:18:01 -0500 Received: from mx1.redhat.com ([209.132.183.28]:40652 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753010AbcL2QOT (ORCPT ); Thu, 29 Dec 2016 11:14:19 -0500 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 , Scott J Norton , Waiman Long Subject: [PATCH v4 05/20] futex: Add a new futex type field into futex_state Date: Thu, 29 Dec 2016 11:13:31 -0500 Message-Id: <1483028026-10305-6-git-send-email-longman@redhat.com> In-Reply-To: <1483028026-10305-1-git-send-email-longman@redhat.com> References: <1483028026-10305-1-git-send-email-longman@redhat.com> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Thu, 29 Dec 2016 16:14:19 +0000 (UTC) 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 | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/kernel/futex.c b/kernel/futex.c index ccec962..c8ff773 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -191,6 +191,10 @@ #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; }; @@ -903,13 +908,14 @@ 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) { task_pi_list_del(state, false); - rt_mutex_proxy_unlock(&state->pi_mutex, state->owner); + if (state->type == TYPE_PI) + rt_mutex_proxy_unlock(&state->pi_mutex, state->owner); } if (current->pi_state_cache) @@ -1062,7 +1068,7 @@ 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)); @@ -1180,6 +1186,7 @@ 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); -- 1.8.3.1