From nobody Thu Dec 18 05:23:37 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 482561C07DA for ; Tue, 10 Dec 2024 14:31:53 +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=1733841114; cv=none; b=Gqhaa4ZKEdYFaxxxEp4ZfJjUimv0jtbEB67oT/pQsqVqaoKONPfGcS3D5/EArIbOqs1xyBdLwFVcmnigKtNSPaiIw7R/ksjjRSqeip54sC/CasD/ED+o/uRO+63pGAO1RUOLARrVvxd4jmJ1KfJTEhDl9aTcTkT73IPlqS73cuk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733841114; c=relaxed/simple; bh=RPAX22n2S6+tLLnaPHMOwC8ALJtiHJFwY5JY+BrKUCk=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=gc7DsiVGfci9a9xQcbNOygnHaJtScJCOVZJPNc7bZJmEIOfkDH1tQmdi7wdF46bvY8g5MIg1KgdtTjYGfO7cUk/4A+6YAqQ1rSLftHDQev65Z2kiskA0XEtDPkz6tzE5GYuvrssbpiTlUJH3/TdPr9EKhRBZvDGVTMdx6qE8E1g= 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=DYWp09p0; 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="DYWp09p0" Received: by mail-pg1-f201.google.com with SMTP id 41be03b00d2f7-7fcd2430636so4145727a12.2 for ; Tue, 10 Dec 2024 06:31:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1733841112; x=1734445912; 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=/ElcxclfcYlOMSELtXDxg5j/9v6WDvHeMeZCbap56uk=; b=DYWp09p0yf0O88y2YrfUhMV9BiPUu5Ic8QPqjMkuVWsqxQv2nPfZEk+n8DIZNcV5J2 MiRMtW9UaZ0VKo7s72kyyHNmxX9J44agad5VS4rGznV+IWaERNk3YZplG5GYlNpnNtrY UWEjtVn8yycNuskyb/3Vr7wqF0x6PPJ4Yse/l2IgHrI+DDHRQ6L/tPqcpi88oSHXR0kJ DNVrdFvAH5Vv2SR9G3a/6VVTGcbXaOJH4h3f1c1CDhSU4CnVwcU0j8UO7bItJB6lRiaB VH6+jmOxNSJ5ignxSzDUAMDdturZ7nq+XeU8R5m4W1crwZ9g2w3p/LFxxLfaP2MjyZhI p39w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1733841112; x=1734445912; 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=/ElcxclfcYlOMSELtXDxg5j/9v6WDvHeMeZCbap56uk=; b=eYiIxx7+10muvjrLB4MReOG/vguKPHDB8VRDw6Vytjy7NxSlEpOAgywZ3WGuYGgccy IDhE+1BJqb6kGn8dSn25WcOz7qrRU6ixJs7zr/excOy0J2OM/Li53EGzs0ZVmBzuxF+N ZwOL0dPVvPC/K7R0ibRaOuWZxAkI1G1ofRoR1idcl4NV9f0YnoyoV2B4pFG+GcBlqEn7 +widU4bNJWlm7iGHHGFkoRFDCi+/YATaIf0Nwe8WUXfHJfy3gNPGjiK4HB+JgF8Ildu8 707wR2J6ajRXnT+7VbQ5y+UPfqBM/2xnUclEIJdcxbImtOEqAt4HN9QMtLecEeKTS6sa NMZA== X-Gm-Message-State: AOJu0Yz8+WYakO0U5Yzf533J+0OnkXKh2S9nwD/4Ty+L4ifpJcSXBtSy L6y/w5iKIH/871ULlvTzBu5Ut/dqeJKu6D80spcuTJ9pRTK7FygTE3ym4tsf4/VWMSEqDx7ZtKD s+lHUgjM6YQ== X-Google-Smtp-Source: AGHT+IEpOTuT8NMAUNbej1hpf+sDkoTSGLcFtU+9aZr0RoEarmp1wDzt1YFH6LiLGII43yjvL6beWvbavDLMAg== X-Received: from pgbfe10.prod.google.com ([2002:a05:6a02:288a:b0:7fd:460b:daa3]) (user=cmllamas job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a21:7895:b0:1e0:cbcf:8917 with SMTP id adf61e73a8af0-1e1b1ac445amr7412686637.21.1733841112554; Tue, 10 Dec 2024 06:31:52 -0800 (PST) Date: Tue, 10 Dec 2024 14:31:05 +0000 In-Reply-To: <20241210143114.661252-1-cmllamas@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20241210143114.661252-1-cmllamas@google.com> X-Mailer: git-send-email 2.47.0.338.g60cca15819-goog Message-ID: <20241210143114.661252-10-cmllamas@google.com> Subject: [PATCH v7 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 b2b97ff19ba2..fcfaf1b899c8 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