From owner-dev-commits-src-all@freebsd.org Wed Dec 30 22:45:53 2020 Return-Path: Delivered-To: dev-commits-src-all@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id DBC484D1166; Wed, 30 Dec 2020 22:45:53 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4D5mbP5twyz4mRl; Wed, 30 Dec 2020 22:45:53 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id BD4DD25D55; Wed, 30 Dec 2020 22:45:53 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.16.1/8.16.1) with ESMTP id 0BUMjroE032418; Wed, 30 Dec 2020 22:45:53 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 0BUMjrQN032417; Wed, 30 Dec 2020 22:45:53 GMT (envelope-from git) Date: Wed, 30 Dec 2020 22:45:53 GMT Message-Id: <202012302245.0BUMjrQN032417@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Piotr Kubaj Subject: git: 6260bfb08742 - main - powerpc: Optimize copyinstr() to avoid repeatedly mapping user strings MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: pkubaj X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: 6260bfb0874280d3fb58ac52699e2aee6ecca8a8 Auto-Submitted: auto-generated X-BeenThere: dev-commits-src-all@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Commit messages for all branches of the src repository List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 30 Dec 2020 22:45:53 -0000 The branch main has been updated by pkubaj (ports committer): URL: https://cgit.FreeBSD.org/src/commit/?id=6260bfb0874280d3fb58ac52699e2aee6ecca8a8 commit 6260bfb0874280d3fb58ac52699e2aee6ecca8a8 Author: Justin Hibbits AuthorDate: 2020-06-04 18:15:15 +0000 Commit: Piotr Kubaj CommitDate: 2020-12-30 22:45:35 +0000 powerpc: Optimize copyinstr() to avoid repeatedly mapping user strings Currently copyinstr() uses fubyte() to read each byte from userspace. However, this means that for each byte, it calls pmap_map_user_ptr() to map the string into memory. This is needlessly wasteful, since the string will rarely ever cross a segment boundary. Instead, map a segment at a time, and copy as much from that segment as possible at a time. Measured with the HPT pmap on powerpc64, this saves roughly 8% time on buildkernel, and 5% on buildworld, in wallclock time. --- sys/powerpc/powerpc/copyinout.c | 46 +++++++++++++++++++++++++++++------------ 1 file changed, 33 insertions(+), 13 deletions(-) diff --git a/sys/powerpc/powerpc/copyinout.c b/sys/powerpc/powerpc/copyinout.c index 76965ad996b8..1528accc0e0e 100644 --- a/sys/powerpc/powerpc/copyinout.c +++ b/sys/powerpc/powerpc/copyinout.c @@ -236,31 +236,51 @@ REMAP(copyin)(const void *udaddr, void *kaddr, size_t len) int REMAP(copyinstr)(const void *udaddr, void *kaddr, size_t len, size_t *done) { + struct thread *td; + pmap_t pm; + jmp_buf env; const char *up; - char *kp; - size_t l; - int rv, c; + char *kp, *p; + size_t i, l, t; + int rv; - kp = kaddr; - up = udaddr; + td = curthread; + pm = &td->td_proc->p_vmspace->vm_pmap; + t = 0; rv = ENAMETOOLONG; - for (l = 0; len-- > 0; l++) { - if ((c = fubyte(up++)) < 0) { + td->td_pcb->pcb_onfault = &env; + if (setjmp(env)) { + rv = EFAULT; + goto done; + } + + kp = kaddr; + up = udaddr; + + while (len > 0) { + if (pmap_map_user_ptr(pm, up, (void **)&p, len, &l)) { rv = EFAULT; - break; + goto done; } - if (!(*kp++ = c)) { - l++; - rv = 0; - break; + for (i = 0; len > 0 && i < l; i++, t++, len--) { + if ((*kp++ = *p++) == 0) { + i++, t++; + rv = 0; + goto done; + } } + + up += l; } +done: + td->td_pcb->pcb_onfault = NULL; + if (done != NULL) { - *done = l; + *done = t; } return (rv);