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 3A207C04FFE for ; Mon, 29 Apr 2024 13:48:34 +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=xrN/lXuIrPQinOwq/9LJj22UyygN7itQLwkMND+1p+o=; b=15dT8TCJWIJRD8ZT0LPBpK6llp zk/onY90HzNBEbeMfw8ukhisP+ETGbtsPYM6EK8pP/F1zDhTs2ei4hcmGSMYHIkYuHPPcy4KJJhYO K1PknVNQwPzk+zo1iAlItiYHV7/jALkVoLS2+/C1Ov5sltohBJEf4+zK3lnfTFfiiGNfdwYm699NE haM0Sk+GB5rvK38yi10R8HQrrSWJzXbN54tYpKo0qiCDOe2/XB41bDMMoA1s7apUEkmuYxsh7z9co /dxfcbyZ5aIV57zWFL2fl5HSJWDk01Lapp4SFfoq0stkScUTGNBIy1rElhoQfNYITIU68I4cyNQdH pYqJYOJg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1s1RMv-00000002zyz-1WTg; Mon, 29 Apr 2024 13:48:33 +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 1s1RMo-00000002zs1-1dpa for linux-um@lists.infradead.org; Mon, 29 Apr 2024 13:48:28 +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=xrN/lXuIrPQinOwq/9LJj22UyygN7itQLwkMND+1p+o=; t=1714398506; x=1715608106; b=qQqp7JMZR2ytaWoOtbEqxnzjgP7aE4yCYTk/OC6W50vP6p0 5tBYR8YM7PuWgtVjG7Jf8EWCpvNYHL9VKKTbzKNbFF9J24g0o60XO0d3Fmq1mb7cWm4/XjnMRaDg5 XdHTGS+FaQN79KDEJTJTVusVZ+oshF5jvzjwn8B7LUYmIifufxPbwzz7DzZoI6Pah/V1gzpsZI3Rg JS/4eMy2CyX29O4Alo4/p6TG+D11qDfZllQnzLEhWbf58t1sVzPYoMgu3v9//7V0/pB14yegad4/T a2CwKH/Jb12HULL50CP2jBeZoH3+pgychQaEwGzowZVWhgHhCgpe4Ne7ifvDmv0Q==; Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.97) (envelope-from ) id 1s1RMl-0000000CW0d-1UdZ; Mon, 29 Apr 2024 15:48:24 +0200 From: benjamin@sipsolutions.net To: linux-um@lists.infradead.org Cc: Benjamin Berg Subject: [PATCH v2 05/12] um: compress memory related stub syscalls while adding them Date: Mon, 29 Apr 2024 15:47:52 +0200 Message-ID: <20240429134759.244517-6-benjamin@sipsolutions.net> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240429134759.244517-1-benjamin@sipsolutions.net> References: <20240429134759.244517-1-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-20240429_064826_485177_AD7D8A51 X-CRM114-Status: GOOD ( 12.98 ) 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; -- 2.44.0