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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id EA634C25B79 for ; Fri, 24 May 2024 21:41:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=8ZPmVD8hRlsUfNUltjrpVc+YttxM3i3TuDGLxLKmd88=; b=QiCv7+wU4MKx6JGf5CCOkM+1Wq DwFRfCWhP6LWD3u1y6ArbQdrKMZzIXK3WiOSKU/RYCXJfjzwIWz+J71zKgFgb35ngtuGzGnxlwASC ipn/JP8nhuJBRRzCbJV6Xhz/kt6GS0cCqys2s/XVPwl3kAM4qOk2sWx5rDSbfORIrQH0xE6IAqtBY wxXEQwcHS561lOtr3o0qBSHF/pNapfX0s9gPF+T/O76eZavyTXV/e6EYGUQssxURw3xp1OqXxF7Yp E5L+JKnq6f6pJK02O/EGq6IgkRebS3TeuKwr5b/qI2FIzg9PF4vA1rFmpoYLFUkHSesStDFcwedqh bcfYOKAw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sAcf5-00000009wdQ-1UhF; Fri, 24 May 2024 21:41:15 +0000 Received: from s3.sipsolutions.net ([2a01:4f8:242:246e::2] helo=sipsolutions.net) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sAcf2-00000009wad-1mIV for linux-um@lists.infradead.org; Fri, 24 May 2024 21:41:13 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sipsolutions.net; s=mail; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Content-Type:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-To: Resent-Cc:Resent-Message-ID; bh=8ZPmVD8hRlsUfNUltjrpVc+YttxM3i3TuDGLxLKmd88=; t=1716586872; x=1717796472; b=nfdwTAXLi23hNht68l/xEeBLdkyZ3yCqy4m2kQuWrhPneKR zU8sx1oPzOUQuHh2O+t9vaN39Mf5HZhSAeMWj0QHRqtPO97JPaUcLURgl87ni9sLfeONywtpa06B/ T2hoRWf0m61713HXsQbOzp7InL52rfXMg/gcP0iZRrRWZnuB6AUW0GUZcH2EpF1EXbJlSHN43cfaN H/KBiFnjMyqaOODj00y1dSrjZTxd4Z/hIlpIpQqXdNLsWa+jAT9XX4d02yQQFgG9RDxvMeylQbTb+ bPOLrjvvLdRZCmZ2GYYWOzvfZYWzrP8sd7Y1ypvXnJjCSLxAYy8+0ywR4mOp/ubw==; Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.97) (envelope-from ) id 1sAcez-00000008ke7-46fm; Fri, 24 May 2024 23:41:10 +0200 From: benjamin@sipsolutions.net To: linux-um@lists.infradead.org Cc: Benjamin Berg Subject: [PATCH v3 05/12] um: compress memory related stub syscalls while adding them Date: Fri, 24 May 2024 23:37:11 +0200 Message-ID: <20240524213718.1757703-6-benjamin@sipsolutions.net> X-Mailer: git-send-email 2.45.1 In-Reply-To: <20240524213718.1757703-1-benjamin@sipsolutions.net> References: <20240524213718.1757703-1-benjamin@sipsolutions.net> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240524_144112_494087_404FF691 X-CRM114-Status: GOOD ( 12.43 ) X-BeenThere: linux-um@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-um" Errors-To: linux-um-bounces+linux-um=archiver.kernel.org@lists.infradead.org From: Benjamin Berg To keep the number of syscalls that the stub has to do lower, compress two consecutive syscalls of the same type if the second is just a continuation of the first. Signed-off-by: Benjamin Berg --- arch/um/os-Linux/skas/mem.c | 39 +++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) diff --git a/arch/um/os-Linux/skas/mem.c b/arch/um/os-Linux/skas/mem.c index 03c8cde0b89b..e3128e080365 100644 --- a/arch/um/os-Linux/skas/mem.c +++ b/arch/um/os-Linux/skas/mem.c @@ -152,12 +152,37 @@ struct stub_syscall *syscall_stub_alloc(struct mm_id *mm_idp) return sc; } +static struct stub_syscall *syscall_stub_get_previous(struct mm_id *mm_idp, + int syscall_type, + unsigned long virt) +{ + if (mm_idp->syscall_data_len > 0) { + struct stub_data *proc_data = (void *) mm_idp->stack; + struct stub_syscall *sc; + + sc = &proc_data->syscall_data[mm_idp->syscall_data_len - 1]; + + if (sc->syscall == syscall_type && + sc->mem.addr + sc->mem.length == virt) + return sc; + } + + return NULL; +} void map(struct mm_id *mm_idp, unsigned long virt, unsigned long len, int prot, int phys_fd, unsigned long long offset) { struct stub_syscall *sc; + /* Compress with previous syscall if that is possible */ + sc = syscall_stub_get_previous(mm_idp, STUB_SYSCALL_MMAP, virt); + if (sc && sc->mem.prot == prot && sc->mem.fd == phys_fd && + sc->mem.offset == MMAP_OFFSET(offset - sc->mem.length)) { + sc->mem.length += len; + return; + } + sc = syscall_stub_alloc(mm_idp); sc->syscall = STUB_SYSCALL_MMAP; sc->mem.addr = virt; @@ -171,6 +196,13 @@ void unmap(struct mm_id *mm_idp, unsigned long addr, unsigned long len) { struct stub_syscall *sc; + /* Compress with previous syscall if that is possible */ + sc = syscall_stub_get_previous(mm_idp, STUB_SYSCALL_MUNMAP, addr); + if (sc) { + sc->mem.length += len; + return; + } + sc = syscall_stub_alloc(mm_idp); sc->syscall = STUB_SYSCALL_MUNMAP; sc->mem.addr = addr; @@ -182,6 +214,13 @@ void protect(struct mm_id *mm_idp, unsigned long addr, unsigned long len, { struct stub_syscall *sc; + /* Compress with previous syscall if that is possible */ + sc = syscall_stub_get_previous(mm_idp, STUB_SYSCALL_MPROTECT, addr); + if (sc && sc->mem.prot == prot) { + sc->mem.length += len; + return; + } + sc = syscall_stub_alloc(mm_idp); sc->syscall = STUB_SYSCALL_MPROTECT; sc->mem.addr = addr; -- 2.45.1