futex: Make futex_mm_init() void

Nothing fails there. Mop up the leftovers of the early version of this,
which did an allocation.

While at it clean up the stubs and the #ifdef comments to make the header
file readable.

Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260602090535.356789395@kernel.org

diff --git a/include/linux/futex.h b/include/linux/futex.h
index 563e8dd671798d81754b0b41360bcaa392d79557..9e6218c2be664666307b285f156cd8246cb364c5 100644 (file)
--- a/include/linux/futex.h
+++ b/include/linux/futex.h
@@ -81,22 +81,20 @@ int futex_hash_prctl(unsigned long arg2, unsigned long arg3, unsigned long arg4)
 #ifdef CONFIG_FUTEX_PRIVATE_HASH
 int futex_hash_allocate_default(void);
 void futex_hash_free(struct mm_struct *mm);
-int futex_mm_init(struct mm_struct *mm);
-
-#else /* !CONFIG_FUTEX_PRIVATE_HASH */
+void futex_mm_init(struct mm_struct *mm);
+#else  /* CONFIG_FUTEX_PRIVATE_HASH */
 static inline int futex_hash_allocate_default(void) { return 0; }
 static inline int futex_hash_free(struct mm_struct *mm) { return 0; }
-static inline int futex_mm_init(struct mm_struct *mm) { return 0; }
-#endif /* CONFIG_FUTEX_PRIVATE_HASH */
+static inline void futex_mm_init(struct mm_struct *mm) { }
+#endif /* !CONFIG_FUTEX_PRIVATE_HASH */
 
-#else /* !CONFIG_FUTEX */
+#else  /* CONFIG_FUTEX */
 static inline void futex_init_task(struct task_struct *tsk) { }
 static inline void futex_exit_recursive(struct task_struct *tsk) { }
 static inline void futex_exit_release(struct task_struct *tsk) { }
 static inline void futex_exec_release(struct task_struct *tsk) { }
-static inline long do_futex(u32 __user *uaddr, int op, u32 val,
-                           ktime_t *timeout, u32 __user *uaddr2,
-                           u32 val2, u32 val3)
+static inline long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout,
+                           u32 __user *uaddr2, u32 val2, u32 val3)
 {
        return -EINVAL;
 }
@@ -104,13 +102,9 @@ static inline int futex_hash_prctl(unsigned long arg2, unsigned long arg3, unsig
 {
        return -EINVAL;
 }
-static inline int futex_hash_allocate_default(void)
-{
-       return 0;
-}
+static inline int futex_hash_allocate_default(void) { return 0; }
 static inline int futex_hash_free(struct mm_struct *mm) { return 0; }
-static inline int futex_mm_init(struct mm_struct *mm) { return 0; }
-
-#endif
+static inline void futex_mm_init(struct mm_struct *mm) { }
+#endif /* !CONFIG_FUTEX */
 
-#endif
+#endif /* _LINUX_FUTEX_H */

diff --git a/kernel/fork.c b/kernel/fork.c
index 5f3fdfdb14c7c7d609917a8114a632c05a8dd234..bb490d97c22232edce6c19d5fbf947343013479c 100644 (file)
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1101,6 +1101,7 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p,
 #endif
        mm_init_uprobes_state(mm);
        hugetlb_count_init(mm);
+       futex_mm_init(mm);
 
        mm_flags_clear_all(mm);
        if (current->mm) {
@@ -1113,11 +1114,8 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p,
                mm->def_flags = 0;
        }
 
-       if (futex_mm_init(mm))
-               goto fail_mm_init;
-
        if (mm_alloc_pgd(mm))
-               goto fail_nopgd;
+               goto fail_mm_init;
 
        if (mm_alloc_id(mm))
                goto fail_noid;
@@ -1144,8 +1142,6 @@ fail_nocontext:
        mm_free_id(mm);
 fail_noid:
        mm_free_pgd(mm);
-fail_nopgd:
-       futex_hash_free(mm);
 fail_mm_init:
        free_mm(mm);
        return NULL;

diff --git a/kernel/futex/core.c b/kernel/futex/core.c
index e7d33d2771ecab27df0215b55f0d000c59ce235f..ec23de4912b381e1afe32e8babf8f2b34b3d8571 100644 (file)
--- a/kernel/futex/core.c
+++ b/kernel/futex/core.c
@@ -1720,7 +1720,7 @@ static bool futex_ref_is_dead(struct futex_private_hash *fph)
        return atomic_long_read(&mm->futex_atomic) == 0;
 }
 
-int futex_mm_init(struct mm_struct *mm)
+void futex_mm_init(struct mm_struct *mm)
 {
        mutex_init(&mm->futex_hash_lock);
        RCU_INIT_POINTER(mm->futex_phash, NULL);
@@ -1729,7 +1729,6 @@ int futex_mm_init(struct mm_struct *mm)
        mm->futex_ref = NULL;
        atomic_long_set(&mm->futex_atomic, 0);
        mm->futex_batches = get_state_synchronize_rcu();
-       return 0;
 }
 
 void futex_hash_free(struct mm_struct *mm)