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-rw-r--r--kernel/futex.c42
1 files changed, 28 insertions, 14 deletions
diff --git a/kernel/futex.c b/kernel/futex.c
index db0c6863e8a3..e65b68677d0b 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -865,21 +865,16 @@ out_state:
865 return 0; 865 return 0;
866} 866}
867 867
868static int 868/*
869lookup_pi_state(u32 uval, struct futex_hash_bucket *hb, 869 * Lookup the task for the TID provided from user space and attach to
870 union futex_key *key, struct futex_pi_state **ps) 870 * it after doing proper sanity checks.
871 */
872static int attach_to_pi_owner(u32 uval, union futex_key *key,
873 struct futex_pi_state **ps)
871{ 874{
872 struct futex_q *match = futex_top_waiter(hb, key);
873 struct futex_pi_state *pi_state = NULL;
874 struct task_struct *p;
875 pid_t pid = uval & FUTEX_TID_MASK; 875 pid_t pid = uval & FUTEX_TID_MASK;
876 876 struct futex_pi_state *pi_state;
877 /* 877 struct task_struct *p;
878 * If there is a waiter on that futex, validate it and
879 * attach to the pi_state when the validation succeeds.
880 */
881 if (match)
882 return attach_to_pi_state(uval, match->pi_state, ps);
883 878
884 /* 879 /*
885 * We are the first waiter - try to look up the real owner and attach 880 * We are the first waiter - try to look up the real owner and attach
@@ -922,7 +917,7 @@ lookup_pi_state(u32 uval, struct futex_hash_bucket *hb,
922 pi_state = alloc_pi_state(); 917 pi_state = alloc_pi_state();
923 918
924 /* 919 /*
925 * Initialize the pi_mutex in locked state and make 'p' 920 * Initialize the pi_mutex in locked state and make @p
926 * the owner of it: 921 * the owner of it:
927 */ 922 */
928 rt_mutex_init_proxy_locked(&pi_state->pi_mutex, p); 923 rt_mutex_init_proxy_locked(&pi_state->pi_mutex, p);
@@ -942,6 +937,25 @@ lookup_pi_state(u32 uval, struct futex_hash_bucket *hb,
942 return 0; 937 return 0;
943} 938}
944 939
940static int lookup_pi_state(u32 uval, struct futex_hash_bucket *hb,
941 union futex_key *key, struct futex_pi_state **ps)
942{
943 struct futex_q *match = futex_top_waiter(hb, key);
944
945 /*
946 * If there is a waiter on that futex, validate it and
947 * attach to the pi_state when the validation succeeds.
948 */
949 if (match)
950 return attach_to_pi_state(uval, match->pi_state, ps);
951
952 /*
953 * We are the first waiter - try to look up the owner based on
954 * @uval and attach to it.
955 */
956 return attach_to_pi_owner(uval, key, ps);
957}
958
945/** 959/**
946 * futex_lock_pi_atomic() - Atomic work required to acquire a pi aware futex 960 * futex_lock_pi_atomic() - Atomic work required to acquire a pi aware futex
947 * @uaddr: the pi futex user address 961 * @uaddr: the pi futex user address