From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 83BBE3CDBD3 for ; Fri, 18 Sep 2026 15:44:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789746297; cv=none; b=TCcSuUi6aBvGOnHIowhhgHNcNGDayxEIax6V4B7VLtVY+Z86pPTVpLeDjd3jDuhsV/MbwOORA/TVZz6yCdY3Px9ps6XHGwkqng0SlaOnhYe3YG1LSbT1uzMzFIbQ89HoO7oGh4d94CZhLuHA3+s2IJFN8IYfHwRtHjNq9ckf97g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789746297; c=relaxed/simple; bh=cLIJje9/hV2s91ONlg/3aGfMqQlncb0aPteZcAdGfzg=; h=Date:To:From:Subject:Message-Id; b=oJPtThK8l0e4IkXA4Ad2kRTHdTgcw48OiHu16deGPB+2KTbSJ8Nz4jPWXREwhuXqUgVuIDbkoYGgb+rQhWsCxxtsBpHqi3T8gW1yzCAMcLwVD00IhKuxC8qTOlZ+k0uywxRTyxQarRhqwxVDENOyEk7bb11HbqGbxBz80e0nEc0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=T6X5uTyB; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="T6X5uTyB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1B2BA1F000FF; Fri, 18 Sep 2026 15:44:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1789746296; bh=7unLB0Jy0YPqHcyEEZh9077078meJ78SpxOSx/mF2fk=; h=Date:To:From:Subject; b=T6X5uTyBGA2B0Fj6ovVx0Bjkde9n9NRp2MSKvX6U/VcisoJv7Lj2CLH8qYdgWmpXL YMVcnrhQDi4LVZ6uIU0rMQzoQNgzuUA8b/STcOBiU/8kUWuuNBOGWwqE3UNVzeMh4V ExFSnN0EJw3o9+ZzqKuIL5V7XWKhK3/C8uJLNtD8= Date: Fri, 18 Sep 2026 08:44:55 -0700 To: mm-commits@vger.kernel.org,surenb@google.com,akpm@linux-foundation.org From: Andrew Morton Subject: + proc-task_mmu-remove-unnecessary-helpers.patch added to mm-new branch Message-Id: <20260918154456.1B2BA1F000FF@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: proc/task_mmu: remove unnecessary helpers has been added to the -mm mm-new branch. Its filename is proc-task_mmu-remove-unnecessary-helpers.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/proc-task_mmu-remove-unnecessary-helpers.patch This patch will later appear in the mm-new branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Note, mm-new is a provisional staging ground for work-in-progress patches, and acceptance into mm-new is a notification for others take notice and to finish up reviews. Please do not hesitate to respond to review feedback and post updated versions to replace or incrementally fixup patches in mm-new. The mm-new branch of mm.git is not included in linux-next If a few days of testing in mm-new is successful, the patch will me moved into mm.git's mm-unstable branch, which is included in linux-next Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via various branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there most days ------------------------------------------------------ From: Suren Baghdasaryan Subject: proc/task_mmu: remove unnecessary helpers Date: Fri, 18 Sep 2026 08:33:12 -0700 Patch series "read proc/pid/smaps_rollup under per-vma lock", v5. proc/pid/smaps_rollup can be read using the combination of RCU and VMA read locks, similar to proc/pid/{maps|smaps|numa_maps}. RCU is required to safely traverse the VMA tree and VMA lock stabilizes the VMA being processed and the pagetable walk. Note that we have to keep the logic to drop mmap_lock on contention because even when using per-VMA locks we might have to fall back to holding the mmap_lock. The first 5 patches are cleanups making later change simpler. The main change is in patch 6. Patch 7 extends existing proc-maps-race tearing test to verify smaps_rollup content. This patch (of 7): When per-vma locks were behind a config option, a number of helper functions were needed to simplify the locking code. Now that these locks are universally available, we can do a little cleanup. Remove lock_vma_range(), unlock_vma_range(), query_vma_setup(), query_vma_teardown() helpers. No functional change intended. Link: https://lore.kernel.org/20260918153318.758387-1-surenb@google.com Link: https://lore.kernel.org/20260918153318.758387-2-surenb@google.com Signed-off-by: Suren Baghdasaryan Signed-off-by: Andrew Morton Reviewed-by: Liam R. Howlett (Oracle) Reviewed-by: Lorenzo Stoakes (ARM) Acked-by: Usama Arif Acked-by: David Hildenbrand (Arm) Cc: Jann Horn Cc: Matthew Wilcox (Oracle) Cc: "Paul E . McKenney" Cc: Pedro Falcato Cc: Vlastimil Babka --- fs/proc/task_mmu.c | 67 ++++++++++--------------------------------- 1 file changed, 17 insertions(+), 50 deletions(-) --- a/fs/proc/task_mmu.c~proc-task_mmu-remove-unnecessary-helpers +++ a/fs/proc/task_mmu.c @@ -160,25 +160,6 @@ static void unlock_ctx_vma(struct proc_m } } -static inline bool lock_vma_range(struct seq_file *m, - struct proc_maps_locking_ctx *lock_ctx) -{ - rcu_read_lock(); - reset_lock_ctx(lock_ctx); - - return true; -} - -static inline void unlock_vma_range(struct proc_maps_locking_ctx *lock_ctx) -{ - if (lock_ctx->mmap_locked) { - unlock_ctx_mm(lock_ctx); - } else { - unlock_ctx_vma(lock_ctx); - rcu_read_unlock(); - } -} - static struct vm_area_struct *get_next_vma(struct proc_maps_private *priv, loff_t last_pos) { @@ -286,13 +267,8 @@ static void *m_start(struct seq_file *m, return NULL; } - if (!lock_vma_range(m, lock_ctx)) { - mmput(mm); - put_task_struct(priv->task); - priv->task = NULL; - return ERR_PTR(-EINTR); - } - + rcu_read_lock(); + reset_lock_ctx(lock_ctx); /* * Reset current position if last_addr was set before * and it's not a sentinel. @@ -325,7 +301,12 @@ static void m_stop(struct seq_file *m, v return; release_task_mempolicy(priv); - unlock_vma_range(&priv->lock_ctx); + if (priv->lock_ctx.mmap_locked) { + unlock_ctx_mm(&priv->lock_ctx); + } else { + unlock_ctx_vma(&priv->lock_ctx); + rcu_read_unlock(); + } mmput(mm); put_task_struct(priv->task); priv->task = NULL; @@ -518,21 +499,6 @@ static int pid_maps_open(struct inode *i PROCMAP_QUERY_VMA_FLAGS \ ) -static int query_vma_setup(struct proc_maps_locking_ctx *lock_ctx) -{ - reset_lock_ctx(lock_ctx); - - return 0; -} - -static void query_vma_teardown(struct proc_maps_locking_ctx *lock_ctx) -{ - if (lock_ctx->mmap_locked) - unlock_ctx_mm(lock_ctx); - else - unlock_ctx_vma(lock_ctx); -} - static struct vm_area_struct *query_vma_find_by_addr(struct proc_maps_locking_ctx *lock_ctx, unsigned long addr) { @@ -653,12 +619,7 @@ static int do_procmap_query(struct mm_st if (!mm || !mmget_not_zero(mm)) return -ESRCH; - err = query_vma_setup(&lock_ctx); - if (err) { - mmput(mm); - return err; - } - + reset_lock_ctx(&lock_ctx); vma = query_matching_vma(&lock_ctx, karg.query_addr, karg.query_flags); if (IS_ERR(vma)) { err = PTR_ERR(vma); @@ -732,7 +693,10 @@ static int do_procmap_query(struct mm_st vm_file = get_file(vma->vm_file); /* unlock vma or mmap_lock, and put mm_struct before copying data to user */ - query_vma_teardown(&lock_ctx); + if (lock_ctx.mmap_locked) + unlock_ctx_mm(&lock_ctx); + else + unlock_ctx_vma(&lock_ctx); mmput(mm); if (karg.build_id_size) { @@ -773,7 +737,10 @@ static int do_procmap_query(struct mm_st return 0; out: - query_vma_teardown(&lock_ctx); + if (lock_ctx.mmap_locked) + unlock_ctx_mm(&lock_ctx); + else + unlock_ctx_vma(&lock_ctx); mmput(mm); out_file: if (vm_file) _ Patches currently in -mm which might be from surenb@google.com are proc-task_mmu-remove-unnecessary-helpers.patch proc-task_mmu-remove-unnecessary-inlines-in-function-definitions.patch proc-task_mmu-clarify-shmem-mapping-walk-conditions-in-smap_gather_stats.patch proc-task_mmu-remove-special-casing-of-smap_gather_stats-start-parameter.patch proc-task_mmu-change-proc_get_vma-to-stop-returning-gate-vma-at-the-end.patch proc-task_mmu-read-proc-pid-smaps_rollup-under-per-vma-lock.patch selftests-proc-add-proc-pid-smaps_rollup-tearing-tests.patch