From nobody Fri Dec 19 08:07:11 2025 Received: from mail-pg1-f201.google.com (mail-pg1-f201.google.com [209.85.215.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3356620C483 for ; Tue, 3 Dec 2024 21:55:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733262937; cv=none; b=hrThPLhtn/M1QzrkwiaAytmfR9XhJ/eofmxxktqNHQQ1asA0NvlTjVXp3UppkQ1TJHIBMLSsAa2/Fgx8qstn8mMgZguQ5uZ1JcloYlmr27POSZxPkmTQjlpM1YYvsAaxCEyeAl3pjMI0mguS/RqmRSvviCJAOyGnHXsFyxkCEms= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733262937; c=relaxed/simple; bh=jIMFjQIvhAgRch+NfQnhZsI2ErhgVUwZ3o5/ejm7D+s=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=iFopj49U0jM94ApNF1uooQ0VpcSmzV67yjnuqjfuHybz5Sw7qh5Y5Gz1F7DE1JZ/+6TnZOH3GOH9XT5XUYO0Uzu57Z7yX2j51AXc7iDPhD63dcaJlabUwweThYFPxtbH1VLH3Kgqj5rY9SAU2+lLLWfG2xY3YlWzK/59g9TBzHM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--cmllamas.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=yKLgLIlo; arc=none smtp.client-ip=209.85.215.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--cmllamas.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="yKLgLIlo" Received: by mail-pg1-f201.google.com with SMTP id 41be03b00d2f7-7eaa7b24162so5784783a12.1 for ; Tue, 03 Dec 2024 13:55:35 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1733262935; x=1733867735; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=k/YUxHrv+12gMgYKuvcmKD0rUQxPjfYrLN7M2OuFebg=; b=yKLgLIlokq5V+ufUQICxYupEssXKyMWfzq3lX/4JWLr8DGNWVr+7TijBstvSZzcmlU Odk+eLIoPl1MHpbJBw6ZrXxshs8+OuBeEPSSUtGbt2h6blhLQ/tPrPH+uA0qE8cwGVEF BMoFAb+NDNPrMHGWShYy2t2VCDBAvE0GOfrY3dGh9QIiweB90virZSasmXW38LX1W7eS QlJE/iFtJzJdMJp0ALqZjozt1GN64nJ7SpRJ3b67KiHlVoZu9PRLUM9lT0r6cMVO49yS A1fEBZWWyH4LvEb1bVn0g06QKASwzAoxM553hCszdKdqYtXi/qKMf1y+YgOiBirFlexe 1d5w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1733262935; x=1733867735; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=k/YUxHrv+12gMgYKuvcmKD0rUQxPjfYrLN7M2OuFebg=; b=B6/YUa0xWPtuILOVboxifk1DU81W6+jdmSfyqo0AJGncNSgja0SQsWL6s1QVL8iJxN NY4cHNhZipmyZHnEL8z5o7gBPhIvEpdOvhRbkqdoE8O1I2GuBRc7R4zc5NjwmT6leo7O vsMJItS4PxCBq/kgi7mAG3I6Skp4vuE8ShAd5xSVzFQzPukKwfMbqqUWi/vD1+j+xJ5K wli1WvvizdrRjtgSRIQ7AV+kQs3iWjGLbWoFF9RgVRXCARScdlj3n7dsuo2rQMKzm0a5 nFKjvh3P9vne3vbCKQagi5P47hJjCA/UlMJ4OSLR466bFZdS9LR5AL0jnO4zROGL2QYC U0lw== X-Gm-Message-State: AOJu0Yx0v5+vWHsa2CXjq77P12hyBW03VsIBd2agclTqsYyYXN75rmpZ bsC/tcz4GoKY3pO8jjjSChJGCjpYOJEogsqCHmBU0swHRsVSvECg8BMGM3FklLF0t023cksSSx/ 7UOsQBrSQNA== X-Google-Smtp-Source: AGHT+IFgwsMtaHHxjbSQxacD0z3q6fPbkuXcnUeDrn4WSoJt5ZuqpkWhaWpRj8qcKcYD7ihEUfE6hGoZoQEPXw== X-Received: from pfbbx24.prod.google.com ([2002:a05:6a00:4298:b0:724:f73b:3c65]) (user=cmllamas job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a20:8403:b0:1e0:be48:177d with SMTP id adf61e73a8af0-1e1653a798dmr6811031637.3.1733262935391; Tue, 03 Dec 2024 13:55:35 -0800 (PST) Date: Tue, 3 Dec 2024 21:54:43 +0000 In-Reply-To: <20241203215452.2820071-1-cmllamas@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20241203215452.2820071-1-cmllamas@google.com> X-Mailer: git-send-email 2.47.0.338.g60cca15819-goog Message-ID: <20241203215452.2820071-10-cmllamas@google.com> Subject: [PATCH v6 9/9] binder: use per-vma lock in page reclaiming From: Carlos Llamas To: Greg Kroah-Hartman , "=?UTF-8?q?Arve=20Hj=C3=B8nnev=C3=A5g?=" , Todd Kjos , Martijn Coenen , Joel Fernandes , Christian Brauner , Carlos Llamas , Suren Baghdasaryan Cc: linux-kernel@vger.kernel.org, kernel-team@android.com, "Liam R. Howlett" Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Use per-vma locking in the shrinker's callback when reclaiming pages, similar to the page installation logic. This minimizes contention with unrelated vmas improving performance. The mmap_sem is still acquired if the per-vma lock cannot be obtained. Cc: Suren Baghdasaryan Suggested-by: Liam R. Howlett Reviewed-by: Suren Baghdasaryan Signed-off-by: Carlos Llamas --- drivers/android/binder_alloc.c | 29 ++++++++++++++++++++++------- 1 file changed, 22 insertions(+), 7 deletions(-) diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c index 5a221296b30c..b58b54f253e6 100644 --- a/drivers/android/binder_alloc.c +++ b/drivers/android/binder_alloc.c @@ -1143,19 +1143,28 @@ enum lru_status binder_alloc_free_page(struct list_= head *item, struct vm_area_struct *vma; struct page *page_to_free; unsigned long page_addr; + int mm_locked =3D 0; size_t index; =20 if (!mmget_not_zero(mm)) goto err_mmget; - if (!mmap_read_trylock(mm)) - goto err_mmap_read_lock_failed; - if (!mutex_trylock(&alloc->mutex)) - goto err_get_alloc_mutex_failed; =20 index =3D mdata->page_index; page_addr =3D alloc->vm_start + index * PAGE_SIZE; =20 - vma =3D vma_lookup(mm, page_addr); + /* attempt per-vma lock first */ + vma =3D lock_vma_under_rcu(mm, page_addr); + if (!vma) { + /* fall back to mmap_lock */ + if (!mmap_read_trylock(mm)) + goto err_mmap_read_lock_failed; + mm_locked =3D 1; + vma =3D vma_lookup(mm, page_addr); + } + + if (!mutex_trylock(&alloc->mutex)) + goto err_get_alloc_mutex_failed; + /* * Since a binder_alloc can only be mapped once, we ensure * the vma corresponds to this mapping by checking whether @@ -1183,7 +1192,10 @@ enum lru_status binder_alloc_free_page(struct list_h= ead *item, } =20 mutex_unlock(&alloc->mutex); - mmap_read_unlock(mm); + if (mm_locked) + mmap_read_unlock(mm); + else + vma_end_read(vma); mmput_async(mm); binder_free_page(page_to_free); =20 @@ -1192,7 +1204,10 @@ enum lru_status binder_alloc_free_page(struct list_h= ead *item, err_invalid_vma: mutex_unlock(&alloc->mutex); err_get_alloc_mutex_failed: - mmap_read_unlock(mm); + if (mm_locked) + mmap_read_unlock(mm); + else + vma_end_read(vma); err_mmap_read_lock_failed: mmput_async(mm); err_mmget: --=20 2.47.0.338.g60cca15819-goog