From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B2A4BC55189 for ; Wed, 22 Apr 2020 00:14:56 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 4A2B720735 for ; Wed, 22 Apr 2020 00:14:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="SssyziSu" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4A2B720735 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id BA6CE8E000F; Tue, 21 Apr 2020 20:14:50 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B7D688E0003; Tue, 21 Apr 2020 20:14:50 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A472F8E000F; Tue, 21 Apr 2020 20:14:50 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0212.hostedemail.com [216.40.44.212]) by kanga.kvack.org (Postfix) with ESMTP id 886398E0003 for ; Tue, 21 Apr 2020 20:14:50 -0400 (EDT) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 4252D180AD820 for ; Wed, 22 Apr 2020 00:14:50 +0000 (UTC) X-FDA: 76733570340.16.duck64_474b974626c4b X-HE-Tag: duck64_474b974626c4b X-Filterd-Recvd-Size: 18660 Received: from mail-pj1-f73.google.com (mail-pj1-f73.google.com [209.85.216.73]) by imf36.hostedemail.com (Postfix) with ESMTP for ; Wed, 22 Apr 2020 00:14:49 +0000 (UTC) Received: by mail-pj1-f73.google.com with SMTP id l40so159248pjb.8 for ; Tue, 21 Apr 2020 17:14:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=zTh8b7RkNjPks24jV7/li7LKOvprI0HH2UU/tYjPtTE=; b=SssyziSuU39OVM/zFl4G5zbSJeluyD8sI7DrMO83k9o5Kz2M1UC3XqTAXZj52y84Zc 8ABC8zm5xEmA2LBf2/DZWYuLGmta8EnyNAekDtZG0TLPPL+QQFWWqqy/R+2nl0yEIQTB ZNmeR2JaaR996a2n0tuu9NjqJoLaNEmmt84zXqfv8eu3dPF7h1KiYvhxu4EdUYruSupu xYBqNBn7bYoGd1E6+Bq7lUhW01GBHWkiHO+LWxqcnsXNAI27rj+mLQ9F9vs0QPnW1p0j +5ECL6FX0sJH4I5RZ2x0RB8TcSk3XZx+n9kVZD/RKbOc+vk33iC9Z5luEbr/2+tBXODy QwXQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=zTh8b7RkNjPks24jV7/li7LKOvprI0HH2UU/tYjPtTE=; b=rwZ+pwoQL47RUjJ9FGdkV2tAz5FL3ZlXhDPPAukXi+QMPWRKPWqIV80toVX6RUYWlD JEQnGItCa4avsHOvd+cT4Uu5OAzdAclbp4oZYj/iES11dZvLNc+MoctVAwQ0Xz8xn9H3 0jmFDBArKdyUyFcHpWy99E/zxgzGBI3NstJWMQucS1fy8ICtHp8HWQCVzcVDZcpKH+R+ UxBtNqBvNFoB6ebXG6+vf3SSBcqKox49y66Vk2IzMyTfDbTtEpq+FOmqVC8CZSLZXtun Ru0Ucr9CJ+I7/iJRzi5jgFSqLLQe1EsyX3ccjuOdOWXEQkzer6IWrEqxE1cTAhLZAebi xV+w== X-Gm-Message-State: AGi0PuYJv6/fi67egrz7fp9UnmvWKBDOhpaOUr/A5dvef+Z6pEd5lILr 94JxC5y/tRSDnaQoMC9+UxvmYw3u3Cc= X-Google-Smtp-Source: APiQypLo0I8zT8VqNAdBkX69fEiQmpb7TKR8EfxzxAqWqjVL5UY8sWJYZQV5U57B5NsqHG0CtpOMfYiR1xk= X-Received: by 2002:a63:ee0b:: with SMTP id e11mr24642910pgi.80.1587514488899; Tue, 21 Apr 2020 17:14:48 -0700 (PDT) Date: Tue, 21 Apr 2020 17:14:22 -0700 In-Reply-To: <20200422001422.232330-1-walken@google.com> Message-Id: <20200422001422.232330-11-walken@google.com> Mime-Version: 1.0 References: <20200422001422.232330-1-walken@google.com> X-Mailer: git-send-email 2.26.1.301.g55bc3eb7cb9-goog Subject: [PATCH v5 10/10] mmap locking API: rename mmap_sem to mmap_lock From: Michel Lespinasse To: Andrew Morton , linux-mm Cc: LKML , Peter Zijlstra , Laurent Dufour , Vlastimil Babka , Matthew Wilcox , Liam Howlett , Jerome Glisse , Davidlohr Bueso , David Rientjes , Hugh Dickins , Ying Han , Jason Gunthorpe , Daniel Jordan , Michel Lespinasse Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Rename the mmap_sem field to mmap_lock. Any new uses of this lock should now go through the new mmap locking api. The mmap_lock is still implemented as a rwsem, though this could change in the future. Signed-off-by: Michel Lespinasse --- arch/ia64/mm/fault.c | 4 ++-- arch/x86/events/core.c | 4 ++-- arch/x86/mm/fault.c | 2 +- drivers/gpu/drm/etnaviv/etnaviv_gem.c | 2 +- include/linux/mm_types.h | 2 +- include/linux/mmap_lock.h | 34 +++++++++++++-------------- mm/hmm.c | 2 +- mm/memory.c | 2 +- mm/mmap.c | 4 ++-- mm/mmu_notifier.c | 18 +++++++------- mm/pagewalk.c | 15 ++++++------ mm/util.c | 4 ++-- 12 files changed, 47 insertions(+), 46 deletions(-) diff --git a/arch/ia64/mm/fault.c b/arch/ia64/mm/fault.c index 693f00b117e1..9b95050c2048 100644 --- a/arch/ia64/mm/fault.c +++ b/arch/ia64/mm/fault.c @@ -70,8 +70,8 @@ ia64_do_page_fault (unsigned long address, unsigned long isr, struct pt_regs *re mask = ((((isr >> IA64_ISR_X_BIT) & 1UL) << VM_EXEC_BIT) | (((isr >> IA64_ISR_W_BIT) & 1UL) << VM_WRITE_BIT)); - /* mmap_sem is performance critical.... */ - prefetchw(&mm->mmap_sem); + /* mmap_lock is performance critical.... */ + prefetchw(&mm->mmap_lock); /* * If we're in an interrupt or have no user context, we must not take the fault.. diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index a619763e96e1..eda117ca1c43 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -2179,10 +2179,10 @@ static void x86_pmu_event_mapped(struct perf_event *event, struct mm_struct *mm) * userspace with CR4.PCE clear while another task is still * doing on_each_cpu_mask() to propagate CR4.PCE. * - * For now, this can't happen because all callers hold mmap_sem + * For now, this can't happen because all callers hold mmap_lock * for write. If this changes, we'll need a different solution. */ - lockdep_assert_held_write(&mm->mmap_sem); + lockdep_assert_held_write(&mm->mmap_lock); if (atomic_inc_return(&mm->context.perf_rdpmc_allowed) == 1) on_each_cpu_mask(mm_cpumask(mm), refresh_pce, NULL, 1); diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 181f66b9049f..35f530f9dfc0 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -1522,7 +1522,7 @@ dotraplinkage void do_page_fault(struct pt_regs *regs, unsigned long hw_error_code, unsigned long address) { - prefetchw(¤t->mm->mmap_sem); + prefetchw(¤t->mm->mmap_lock); trace_page_fault_entries(regs, hw_error_code, address); if (unlikely(kmmio_fault(regs, address))) diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gem.c b/drivers/gpu/drm/etnaviv/etnaviv_gem.c index dc9ef302f517..701f3995f621 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_gem.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_gem.c @@ -661,7 +661,7 @@ static int etnaviv_gem_userptr_get_pages(struct etnaviv_gem_object *etnaviv_obj) struct etnaviv_gem_userptr *userptr = &etnaviv_obj->userptr; int ret, pinned = 0, npages = etnaviv_obj->base.size >> PAGE_SHIFT; - might_lock_read(¤t->mm->mmap_sem); + might_lock_read(¤t->mm->mmap_lock); if (userptr->mm != current->mm) return -EPERM; diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 4aba6c0c2ba8..d13b90399c16 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -436,7 +436,7 @@ struct mm_struct { spinlock_t page_table_lock; /* Protects page tables and some * counters */ - struct rw_semaphore mmap_sem; + struct rw_semaphore mmap_lock; struct list_head mmlist; /* List of maybe swapped mm's. These * are globally strung together off diff --git a/include/linux/mmap_lock.h b/include/linux/mmap_lock.h index f7a3a9550cc5..f8db53f10c1c 100644 --- a/include/linux/mmap_lock.h +++ b/include/linux/mmap_lock.h @@ -4,67 +4,67 @@ #include #define MMAP_LOCK_INITIALIZER(name) \ - .mmap_sem = __RWSEM_INITIALIZER(name.mmap_sem), + .mmap_lock = __RWSEM_INITIALIZER(name.mmap_lock), static inline void mmap_init_lock(struct mm_struct *mm) { - init_rwsem(&mm->mmap_sem); + init_rwsem(&mm->mmap_lock); } static inline void mmap_write_lock(struct mm_struct *mm) { - down_write(&mm->mmap_sem); + down_write(&mm->mmap_lock); } static inline void mmap_write_lock_nested(struct mm_struct *mm, int subclass) { - down_write_nested(&mm->mmap_sem, subclass); + down_write_nested(&mm->mmap_lock, subclass); } static inline int mmap_write_lock_killable(struct mm_struct *mm) { - return down_write_killable(&mm->mmap_sem); + return down_write_killable(&mm->mmap_lock); } static inline bool mmap_write_trylock(struct mm_struct *mm) { - return down_write_trylock(&mm->mmap_sem) != 0; + return down_write_trylock(&mm->mmap_lock) != 0; } static inline void mmap_write_unlock(struct mm_struct *mm) { - up_write(&mm->mmap_sem); + up_write(&mm->mmap_lock); } static inline void mmap_write_downgrade(struct mm_struct *mm) { - downgrade_write(&mm->mmap_sem); + downgrade_write(&mm->mmap_lock); } static inline void mmap_read_lock(struct mm_struct *mm) { - down_read(&mm->mmap_sem); + down_read(&mm->mmap_lock); } static inline int mmap_read_lock_killable(struct mm_struct *mm) { - return down_read_killable(&mm->mmap_sem); + return down_read_killable(&mm->mmap_lock); } static inline bool mmap_read_trylock(struct mm_struct *mm) { - return down_read_trylock(&mm->mmap_sem) != 0; + return down_read_trylock(&mm->mmap_lock) != 0; } static inline void mmap_read_unlock(struct mm_struct *mm) { - up_read(&mm->mmap_sem); + up_read(&mm->mmap_lock); } static inline bool mmap_read_trylock_non_owner(struct mm_struct *mm) { - if (down_read_trylock(&mm->mmap_sem)) { - rwsem_release(&mm->mmap_sem.dep_map, _RET_IP_); + if (down_read_trylock(&mm->mmap_lock)) { + rwsem_release(&mm->mmap_lock.dep_map, _RET_IP_); return true; } return false; @@ -72,15 +72,15 @@ static inline bool mmap_read_trylock_non_owner(struct mm_struct *mm) static inline void mmap_read_unlock_non_owner(struct mm_struct *mm) { - up_read_non_owner(&mm->mmap_sem); + up_read_non_owner(&mm->mmap_lock); } static inline void mmap_assert_locked(struct mm_struct *mm) { if (IS_ENABLED(CONFIG_LOCKDEP) && debug_locks) - VM_BUG_ON_MM(!lockdep_is_held(&mm->mmap_sem), mm); + VM_BUG_ON_MM(!lockdep_is_held(&mm->mmap_lock), mm); else - VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_sem), mm); + VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_lock), mm); } #endif /* _LINUX_MMAP_LOCK_H */ diff --git a/mm/hmm.c b/mm/hmm.c index 280585833adf..8660aec6aafa 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -581,7 +581,7 @@ long hmm_range_fault(struct hmm_range *range) struct mm_struct *mm = range->notifier->mm; int ret; - lockdep_assert_held(&mm->mmap_sem); + lockdep_assert_held(&mm->mmap_lock); do { /* If range is no longer valid force retry. */ diff --git a/mm/memory.c b/mm/memory.c index 20f98ea8968e..c2963e7affa9 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -4811,7 +4811,7 @@ void __might_fault(const char *file, int line) __might_sleep(file, line, 0); #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) if (current->mm) - might_lock_read(¤t->mm->mmap_sem); + might_lock_read(¤t->mm->mmap_lock); #endif } EXPORT_SYMBOL(__might_fault); diff --git a/mm/mmap.c b/mm/mmap.c index 2f4ffccc5972..80a47031d5db 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -3474,7 +3474,7 @@ static void vm_lock_anon_vma(struct mm_struct *mm, struct anon_vma *anon_vma) * The LSB of head.next can't change from under us * because we hold the mm_all_locks_mutex. */ - down_write_nest_lock(&anon_vma->root->rwsem, &mm->mmap_sem); + down_write_nest_lock(&anon_vma->root->rwsem, &mm->mmap_lock); /* * We can safely modify head.next after taking the * anon_vma->root->rwsem. If some other vma in this mm shares @@ -3504,7 +3504,7 @@ static void vm_lock_mapping(struct mm_struct *mm, struct address_space *mapping) */ if (test_and_set_bit(AS_MM_ALL_LOCKS, &mapping->flags)) BUG(); - down_write_nest_lock(&mapping->i_mmap_rwsem, &mm->mmap_sem); + down_write_nest_lock(&mapping->i_mmap_rwsem, &mm->mmap_lock); } } diff --git a/mm/mmu_notifier.c b/mm/mmu_notifier.c index cfd0a03bf5cc..6717278d6d49 100644 --- a/mm/mmu_notifier.c +++ b/mm/mmu_notifier.c @@ -599,7 +599,7 @@ void __mmu_notifier_invalidate_range(struct mm_struct *mm, } /* - * Same as mmu_notifier_register but here the caller must hold the mmap_sem in + * Same as mmu_notifier_register but here the caller must hold the mmap_lock in * write mode. A NULL mn signals the notifier is being registered for itree * mode. */ @@ -609,7 +609,7 @@ int __mmu_notifier_register(struct mmu_notifier *subscription, struct mmu_notifier_subscriptions *subscriptions = NULL; int ret; - lockdep_assert_held_write(&mm->mmap_sem); + lockdep_assert_held_write(&mm->mmap_lock); BUG_ON(atomic_read(&mm->mm_users) <= 0); if (IS_ENABLED(CONFIG_LOCKDEP)) { @@ -623,7 +623,7 @@ int __mmu_notifier_register(struct mmu_notifier *subscription, /* * kmalloc cannot be called under mm_take_all_locks(), but we * know that mm->notifier_subscriptions can't change while we - * hold the write side of the mmap_sem. + * hold the write side of the mmap_lock. */ subscriptions = kzalloc( sizeof(struct mmu_notifier_subscriptions), GFP_KERNEL); @@ -655,7 +655,7 @@ int __mmu_notifier_register(struct mmu_notifier *subscription, * readers. acquire can only be used while holding the mmgrab or * mmget, and is safe because once created the * mmu_notifier_subscriptions is not freed until the mm is destroyed. - * As above, users holding the mmap_sem or one of the + * As above, users holding the mmap_lock or one of the * mm_take_all_locks() do not need to use acquire semantics. */ if (subscriptions) @@ -689,7 +689,7 @@ EXPORT_SYMBOL_GPL(__mmu_notifier_register); * @mn: The notifier to attach * @mm: The mm to attach the notifier to * - * Must not hold mmap_sem nor any other VM related lock when calling + * Must not hold mmap_lock nor any other VM related lock when calling * this registration function. Must also ensure mm_users can't go down * to zero while this runs to avoid races with mmu_notifier_release, * so mm has to be current->mm or the mm should be pinned safely such @@ -750,7 +750,7 @@ find_get_mmu_notifier(struct mm_struct *mm, const struct mmu_notifier_ops *ops) * are the same. * * Each call to mmu_notifier_get() must be paired with a call to - * mmu_notifier_put(). The caller must hold the write side of mm->mmap_sem. + * mmu_notifier_put(). The caller must hold the write side of mm->mmap_lock. * * While the caller has a mmu_notifier get the mm pointer will remain valid, * and can be converted to an active mm pointer via mmget_not_zero(). @@ -761,7 +761,7 @@ struct mmu_notifier *mmu_notifier_get_locked(const struct mmu_notifier_ops *ops, struct mmu_notifier *subscription; int ret; - lockdep_assert_held_write(&mm->mmap_sem); + lockdep_assert_held_write(&mm->mmap_lock); if (mm->notifier_subscriptions) { subscription = find_get_mmu_notifier(mm, ops); @@ -983,7 +983,7 @@ int mmu_interval_notifier_insert(struct mmu_interval_notifier *interval_sub, struct mmu_notifier_subscriptions *subscriptions; int ret; - might_lock(&mm->mmap_sem); + might_lock(&mm->mmap_lock); subscriptions = smp_load_acquire(&mm->notifier_subscriptions); if (!subscriptions || !subscriptions->has_itree) { @@ -1006,7 +1006,7 @@ int mmu_interval_notifier_insert_locked( mm->notifier_subscriptions; int ret; - lockdep_assert_held_write(&mm->mmap_sem); + lockdep_assert_held_write(&mm->mmap_lock); if (!subscriptions || !subscriptions->has_itree) { ret = __mmu_notifier_register(NULL, mm); diff --git a/mm/pagewalk.c b/mm/pagewalk.c index 928df1638c30..d669a3146c0f 100644 --- a/mm/pagewalk.c +++ b/mm/pagewalk.c @@ -373,8 +373,9 @@ static int __walk_page_range(unsigned long start, unsigned long end, * caller-specific data to callbacks, @private should be helpful. * * Locking: - * Callers of walk_page_range() and walk_page_vma() should hold @mm->mmap_sem, - * because these function traverse vma list and/or access to vma's data. + * Callers of walk_page_range() and walk_page_vma() should hold + * @mm->mmap_lock, because these function traverse the vma list + * and/or access the vma's data. */ int walk_page_range(struct mm_struct *mm, unsigned long start, unsigned long end, const struct mm_walk_ops *ops, @@ -395,7 +396,7 @@ int walk_page_range(struct mm_struct *mm, unsigned long start, if (!walk.mm) return -EINVAL; - lockdep_assert_held(&walk.mm->mmap_sem); + lockdep_assert_held(&walk.mm->mmap_lock); vma = find_vma(walk.mm, start); do { @@ -453,7 +454,7 @@ int walk_page_range_novma(struct mm_struct *mm, unsigned long start, if (start >= end || !walk.mm) return -EINVAL; - lockdep_assert_held(&walk.mm->mmap_sem); + lockdep_assert_held(&walk.mm->mmap_lock); return __walk_page_range(start, end, &walk); } @@ -472,7 +473,7 @@ int walk_page_vma(struct vm_area_struct *vma, const struct mm_walk_ops *ops, if (!walk.mm) return -EINVAL; - lockdep_assert_held(&walk.mm->mmap_sem); + lockdep_assert_held(&walk.mm->mmap_lock); err = walk_page_test(vma->vm_start, vma->vm_end, &walk); if (err > 0) @@ -498,11 +499,11 @@ int walk_page_vma(struct vm_area_struct *vma, const struct mm_walk_ops *ops, * Also see walk_page_range() for additional information. * * Locking: - * This function can't require that the struct mm_struct::mmap_sem is held, + * This function can't require that the struct mm_struct::mmap_lock is held, * since @mapping may be mapped by multiple processes. Instead * @mapping->i_mmap_rwsem must be held. This might have implications in the * callbacks, and it's up tho the caller to ensure that the - * struct mm_struct::mmap_sem is not needed. + * struct mm_struct::mmap_lock is not needed. * * Also this means that a caller can't rely on the struct * vm_area_struct::vm_flags to be constant across a call, diff --git a/mm/util.c b/mm/util.c index ea2e15b21446..56c562f7ad19 100644 --- a/mm/util.c +++ b/mm/util.c @@ -425,7 +425,7 @@ void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack) * @bypass_rlim: %true if checking RLIMIT_MEMLOCK should be skipped * * Assumes @task and @mm are valid (i.e. at least one reference on each), and - * that mmap_sem is held as writer. + * that mmap_lock is held as writer. * * Return: * * 0 on success @@ -437,7 +437,7 @@ int __account_locked_vm(struct mm_struct *mm, unsigned long pages, bool inc, unsigned long locked_vm, limit; int ret = 0; - lockdep_assert_held_write(&mm->mmap_sem); + lockdep_assert_held_write(&mm->mmap_lock); locked_vm = mm->locked_vm; if (inc) { -- 2.26.1.301.g55bc3eb7cb9-goog