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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9B978C77B7A for ; Tue, 30 May 2023 19:44:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233305AbjE3Tn7 (ORCPT ); Tue, 30 May 2023 15:43:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34712 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233317AbjE3Tn5 (ORCPT ); Tue, 30 May 2023 15:43:57 -0400 Received: from mail-yw1-x114a.google.com (mail-yw1-x114a.google.com [IPv6:2607:f8b0:4864:20::114a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 15D42116 for ; Tue, 30 May 2023 12:43:55 -0700 (PDT) Received: by mail-yw1-x114a.google.com with SMTP id 00721157ae682-565b499da27so3286667b3.1 for ; Tue, 30 May 2023 12:43:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1685475834; x=1688067834; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=SNweh4ADCvFwR9iO9ggEaO8z71m4kgTRxYfIvru8nNM=; b=dCZoL45ayuC3cJzyp4Uw0dErcMDc4KHQ0kX2kEQhBcZtXcR3jF51on22wERsfG76F1 KhL0Ocq1Nj8h5zmxEn6rVmVjA5zdLfWIPPSKrgK7P1hCV5r1smcFCbDl0tNGGnrroV/i wVGzd1wDfhyggC+lf9uGBB1OMGSanI1sHIRCgYDdgbMVW2MD0AIe+JII2T1+wnIE6y9K tBcWJvORWmV+FxjtBdPFsgTaDjmD+yFNC3zzXr9fr7BMaVAmwl/tTxmlrzo2E7XJ9ib9 So4Cs/OlDRGBrjveBfvrUUAOsGYUzqJ1rdBdCe4a3SHlRluN+INVAhkGMbX814VPUgBG Msww== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1685475834; x=1688067834; 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=SNweh4ADCvFwR9iO9ggEaO8z71m4kgTRxYfIvru8nNM=; b=ArcFxlIDA3VwFPFPM2XF23Ybg2DIjCvCclMZ5ZSQzgUJ16P1/G2jOSU511SvtvknQ4 JFIhqjCrYQtQ6lD7t20nzHPPWfcn2N/W6P2/V1jQ+sE8Ktxec3gr2QSmeMjuvY00UOEx +0oJr/z0a1ASSC6R97YkDpPK8YxDJp4wtZztIxJ5mtyISaUUihxM0GjtyMwiTbZEBhxB 5KQT4xrpC2vcRQBwkrMGtDq1fPqrePIMXUMRRVJL4lgtXAIcbx5X5KFU+a5DKogNiJ7a ziIzY7r0wBqNOMAeHWDqzozDlUi7LyhmmFDUxLhPNVFpYRJJyzNxWzift/R727DbVU8T JdXg== X-Gm-Message-State: AC+VfDzAdxhxHUnVohYbPP5Dr/ycHD/zp79B95202aSgP8VQqcfqVpyo Sj7c1kn4JcbiOoE6k0Pmf2fs17z9AknqoMe4WYvFeWg9NrzPSEygh+15wQfCmz8xyiCWKcATLdP qk32ufZeVLf/EFZukHjjCtvzpEyvQ1Gq9IErkTr9h9u+/5oEcY0ZcEgPtr6RRaZpMzWs= X-Google-Smtp-Source: ACHHUZ7A/twy6+kg7XBnN2tKyjzg0tkY8Y+zTm1RlUR4FP2c75vuXPpAk3UlNAg8fq26+P0wt6aHBbnm4/ogZg== X-Received: from xllamas.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5070]) (user=cmllamas job=sendgmr) by 2002:a25:a4a9:0:b0:ba8:1e5f:8514 with SMTP id g38-20020a25a4a9000000b00ba81e5f8514mr1941975ybi.5.1685475834172; Tue, 30 May 2023 12:43:54 -0700 (PDT) Date: Tue, 30 May 2023 19:43:35 +0000 In-Reply-To: <20230530194338.1683009-1-cmllamas@google.com> Mime-Version: 1.0 References: <20230530194338.1683009-1-cmllamas@google.com> X-Mailer: git-send-email 2.41.0.rc0.172.g3f132b7071-goog Message-ID: <20230530194338.1683009-2-cmllamas@google.com> Subject: [PATCH 5.15.y 2/5] Revert "binder_alloc: add missing mmap_lock calls when using the VMA" From: Carlos Llamas To: stable@vger.kernel.org Cc: Carlos Llamas , Liam Howlett , Suren Baghdasaryan , Greg Kroah-Hartman Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org commit b15655b12ddca7ade09807f790bafb6fab61b50a upstream. This reverts commit 44e602b4e52f70f04620bbbf4fe46ecb40170bde. This caused a performance regression particularly when pages are getting reclaimed. We don't need to acquire the mmap_lock to determine when the binder buffer has been fully initialized. A subsequent patch will bring back the lockless approach for this. [cmllamas: resolved trivial conflicts with renaming of alloc->mm] Fixes: 44e602b4e52f ("binder_alloc: add missing mmap_lock calls when using the VMA") Cc: Liam Howlett Cc: Suren Baghdasaryan Cc: stable@vger.kernel.org Signed-off-by: Carlos Llamas Link: https://lore.kernel.org/r/20230502201220.1756319-1-cmllamas@google.com Signed-off-by: Greg Kroah-Hartman [cmllamas: revert of original commit 44e602b4e52f applied clean] Signed-off-by: Carlos Llamas --- drivers/android/binder_alloc.c | 31 ++++++++++--------------------- 1 file changed, 10 insertions(+), 21 deletions(-) diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c index 6acfb896b2e5..f1dc5326a1d9 100644 --- a/drivers/android/binder_alloc.c +++ b/drivers/android/binder_alloc.c @@ -394,15 +394,12 @@ static struct binder_buffer *binder_alloc_new_buf_locked( size_t size, data_offsets_size; int ret; - mmap_read_lock(alloc->vma_vm_mm); if (!binder_alloc_get_vma(alloc)) { - mmap_read_unlock(alloc->vma_vm_mm); binder_alloc_debug(BINDER_DEBUG_USER_ERROR, "%d: binder_alloc_buf, no vma\n", alloc->pid); return ERR_PTR(-ESRCH); } - mmap_read_unlock(alloc->vma_vm_mm); data_offsets_size = ALIGN(data_size, sizeof(void *)) + ALIGN(offsets_size, sizeof(void *)); @@ -930,25 +927,17 @@ void binder_alloc_print_pages(struct seq_file *m, * Make sure the binder_alloc is fully initialized, otherwise we might * read inconsistent state. */ - - mmap_read_lock(alloc->vma_vm_mm); - if (binder_alloc_get_vma(alloc) == NULL) { - mmap_read_unlock(alloc->vma_vm_mm); - goto uninitialized; - } - - mmap_read_unlock(alloc->vma_vm_mm); - for (i = 0; i < alloc->buffer_size / PAGE_SIZE; i++) { - page = &alloc->pages[i]; - if (!page->page_ptr) - free++; - else if (list_empty(&page->lru)) - active++; - else - lru++; + if (binder_alloc_get_vma(alloc) != NULL) { + for (i = 0; i < alloc->buffer_size / PAGE_SIZE; i++) { + page = &alloc->pages[i]; + if (!page->page_ptr) + free++; + else if (list_empty(&page->lru)) + active++; + else + lru++; + } } - -uninitialized: mutex_unlock(&alloc->mutex); seq_printf(m, " pages: %d:%d:%d\n", active, lru, free); seq_printf(m, " pages high watermark: %zu\n", alloc->pages_high); -- 2.41.0.rc0.172.g3f132b7071-goog