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 98ED4C4332F for ; Wed, 9 Nov 2022 03:36:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230140AbiKIDgy (ORCPT ); Tue, 8 Nov 2022 22:36:54 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55628 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230225AbiKIDgu (ORCPT ); Tue, 8 Nov 2022 22:36:50 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D03C3E6B for ; Tue, 8 Nov 2022 19:35:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1667964950; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=nbbRgpejA7sfz74mbd3BvkH0wE+DwK1tqMCX8jqv3XU=; b=aZurhOccs5cRnATbUB1fQe7BgguZbfchyoBFhCrjWO98ny2dKAbYXIK2PGibilgent5joM sKQe6jnsdvfEjDP6Pzunc4PPbuLMlHlm7r0veQ9dd8VG205F40f6WfxSnLNEemO27evoQf zBvuG4BzPM5481rwf8fgWrL+MAKXdy4= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-451-vGWf6ADhPLuE-5SDkR8Wmw-1; Tue, 08 Nov 2022 22:35:46 -0500 X-MC-Unique: vGWf6ADhPLuE-5SDkR8Wmw-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 5C8AA101A52A; Wed, 9 Nov 2022 03:35:46 +0000 (UTC) Received: from MiWiFi-R3L-srv.redhat.com (ovpn-12-86.pek2.redhat.com [10.72.12.86]) by smtp.corp.redhat.com (Postfix) with ESMTP id D78E610197; Wed, 9 Nov 2022 03:35:42 +0000 (UTC) From: Baoquan He To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, akpm@linux-foundation.org, stephen.s.brennan@oracle.com, urezki@gmail.com, hch@infradead.org, Baoquan He Subject: [PATCH RFC 1/3] mm/vmalloc.c: add used_map into vmap_block to track space of vmap_block Date: Wed, 9 Nov 2022 11:35:32 +0800 Message-Id: <20221109033535.269229-2-bhe@redhat.com> In-Reply-To: <20221109033535.269229-1-bhe@redhat.com> References: <20221109033535.269229-1-bhe@redhat.com> MIME-Version: 1.0 Content-type: text/plain Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In one vmap_block area, there could be three types of regions: used region which is allocated through vb_alloc(), dirty region which is freed through vb_free() and free region. Among them, only used region has available data, while there's no way to track those used regions currently. Here, add bitmap field used_map into vmap_block, and set/clear it during allocation or freeing regions of vmap_block area. This is a preparatoin for later use. Signed-off-by: Baoquan He --- mm/vmalloc.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/mm/vmalloc.c b/mm/vmalloc.c index ccaa461998f3..5d3fd3e6fe09 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -1896,6 +1896,7 @@ struct vmap_block { spinlock_t lock; struct vmap_area *va; unsigned long free, dirty; + DECLARE_BITMAP(used_map, VMAP_BBMAP_BITS); unsigned long dirty_min, dirty_max; /*< dirty range */ struct list_head free_list; struct rcu_head rcu_head; @@ -1972,10 +1973,12 @@ static void *new_vmap_block(unsigned int order, gfp_t gfp_mask) vb->va = va; /* At least something should be left free */ BUG_ON(VMAP_BBMAP_BITS <= (1UL << order)); + bitmap_zero(vb->used_map, VMAP_BBMAP_BITS); vb->free = VMAP_BBMAP_BITS - (1UL << order); vb->dirty = 0; vb->dirty_min = VMAP_BBMAP_BITS; vb->dirty_max = 0; + bitmap_set(vb->used_map, 0, (1UL << order)); INIT_LIST_HEAD(&vb->free_list); vb_idx = addr_to_vb_idx(va->va_start); @@ -2081,6 +2084,7 @@ static void *vb_alloc(unsigned long size, gfp_t gfp_mask) pages_off = VMAP_BBMAP_BITS - vb->free; vaddr = vmap_block_vaddr(vb->va->va_start, pages_off); vb->free -= 1UL << order; + bitmap_set(vb->used_map, pages_off, (1UL << order)); if (vb->free == 0) { spin_lock(&vbq->lock); list_del_rcu(&vb->free_list); @@ -2114,6 +2118,9 @@ static void vb_free(unsigned long addr, unsigned long size) order = get_order(size); offset = (addr & (VMAP_BLOCK_SIZE - 1)) >> PAGE_SHIFT; vb = xa_load(&vmap_blocks, addr_to_vb_idx(addr)); + spin_lock(&vb->lock); + bitmap_clear(vb->used_map, offset, (1UL << order)); + spin_unlock(&vb->lock); vunmap_range_noflush(addr, addr + size); -- 2.34.1