From owner-svn-src-head@FreeBSD.ORG Wed Mar 27 11:34:28 2013 Return-Path: Delivered-To: svn-src-head@freebsd.org Received: from mx1.freebsd.org (mx1.FreeBSD.org [8.8.178.115]) by hub.freebsd.org (Postfix) with ESMTP id 5D735356; Wed, 27 Mar 2013 11:34:28 +0000 (UTC) (envelope-from kib@FreeBSD.org) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:1900:2254:2068::e6a:0]) by mx1.freebsd.org (Postfix) with ESMTP id 5048716F; Wed, 27 Mar 2013 11:34:28 +0000 (UTC) Received: from svn.freebsd.org ([127.0.1.70]) by svn.freebsd.org (8.14.6/8.14.6) with ESMTP id r2RBYS9k077956; Wed, 27 Mar 2013 11:34:28 GMT (envelope-from kib@svn.freebsd.org) Received: (from kib@localhost) by svn.freebsd.org (8.14.6/8.14.5/Submit) id r2RBYRjl077953; Wed, 27 Mar 2013 11:34:27 GMT (envelope-from kib@svn.freebsd.org) Message-Id: <201303271134.r2RBYRjl077953@svn.freebsd.org> From: Konstantin Belousov Date: Wed, 27 Mar 2013 11:34:27 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r248792 - in head/sys: kern sys X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 27 Mar 2013 11:34:28 -0000 Author: kib Date: Wed Mar 27 11:34:27 2013 New Revision: 248792 URL: http://svnweb.freebsd.org/changeset/base/248792 Log: Add dev_strategy_csw() function, which is similar to dev_strategy() but assumes that a thread reference was already obtained on the passed device. Use the function from physio(), to avoid two extra dev_mtx lock and unlock. Note that physio() is always used as the cdevsw method, or is called from a cdevsw method, and the caller already owns the reference. dev_strategy() is left to keep KPI intact, but now it is implemented as a wrapper around dev_strategy_csw(). Do some style cleanup in physio(). Requested and reviewed by: kan (previous version) Sponsored by: The FreeBSD Foundation MFC after: 2 weeks Modified: head/sys/kern/kern_physio.c head/sys/kern/vfs_bio.c head/sys/sys/conf.h Modified: head/sys/kern/kern_physio.c ============================================================================== --- head/sys/kern/kern_physio.c Wed Mar 27 11:31:39 2013 (r248791) +++ head/sys/kern/kern_physio.c Wed Mar 27 11:34:27 2013 (r248792) @@ -34,11 +34,11 @@ __FBSDID("$FreeBSD$"); int physio(struct cdev *dev, struct uio *uio, int ioflag) { - int i; - int error; + struct buf *bp; + struct cdevsw *csw; caddr_t sa; u_int iolen; - struct buf *bp; + int error, i, mapped; /* Keep the process UPAGES from being swapped. XXX: why ? */ PHOLD(curproc); @@ -91,11 +91,8 @@ physio(struct cdev *dev, struct uio *uio bp->b_blkno = btodb(bp->b_offset); + csw = dev->si_devsw; if (uio->uio_segflg == UIO_USERSPACE) { - struct cdevsw *csw; - int mapped; - - csw = dev->si_devsw; if (csw != NULL && (csw->d_flags & D_UNMAPPED_IO) != 0) mapped = 0; @@ -107,7 +104,7 @@ physio(struct cdev *dev, struct uio *uio } } - dev_strategy(dev, bp); + dev_strategy_csw(dev, csw, bp); if (uio->uio_rw == UIO_READ) bwait(bp, PRIBIO, "physrd"); else Modified: head/sys/kern/vfs_bio.c ============================================================================== --- head/sys/kern/vfs_bio.c Wed Mar 27 11:31:39 2013 (r248791) +++ head/sys/kern/vfs_bio.c Wed Mar 27 11:34:27 2013 (r248792) @@ -3687,11 +3687,34 @@ void dev_strategy(struct cdev *dev, struct buf *bp) { struct cdevsw *csw; - struct bio *bip; int ref; - if ((!bp->b_iocmd) || (bp->b_iocmd & (bp->b_iocmd - 1))) - panic("b_iocmd botch"); + KASSERT(dev->si_refcount > 0, + ("dev_strategy on un-referenced struct cdev *(%s) %p", + devtoname(dev), dev)); + + csw = dev_refthread(dev, &ref); + dev_strategy_csw(dev, csw, bp); + dev_relthread(dev, ref); +} + +void +dev_strategy_csw(struct cdev *dev, struct cdevsw *csw, struct buf *bp) +{ + struct bio *bip; + + KASSERT(bp->b_iocmd == BIO_READ || bp->b_iocmd == BIO_WRITE, + ("b_iocmd botch")); + KASSERT(((dev->si_flags & SI_ETERNAL) != 0 && csw != NULL) || + dev->si_threadcount > 0, + ("dev_strategy_csw threadcount cdev *(%s) %p", devtoname(dev), + dev)); + if (csw == NULL) { + bp->b_error = ENXIO; + bp->b_ioflags = BIO_ERROR; + bufdone(bp); + return; + } for (;;) { bip = g_new_bio(); if (bip != NULL) @@ -3707,19 +3730,7 @@ dev_strategy(struct cdev *dev, struct bu bip->bio_done = bufdonebio; bip->bio_caller2 = bp; bip->bio_dev = dev; - KASSERT(dev->si_refcount > 0, - ("dev_strategy on un-referenced struct cdev *(%s)", - devtoname(dev))); - csw = dev_refthread(dev, &ref); - if (csw == NULL) { - g_destroy_bio(bip); - bp->b_error = ENXIO; - bp->b_ioflags = BIO_ERROR; - bufdone(bp); - return; - } (*csw->d_strategy)(bip); - dev_relthread(dev, ref); } /* Modified: head/sys/sys/conf.h ============================================================================== --- head/sys/sys/conf.h Wed Mar 27 11:31:39 2013 (r248791) +++ head/sys/sys/conf.h Wed Mar 27 11:34:27 2013 (r248792) @@ -255,6 +255,7 @@ void dev_ref(struct cdev *dev); void dev_refl(struct cdev *dev); void dev_rel(struct cdev *dev); void dev_strategy(struct cdev *dev, struct buf *bp); +void dev_strategy_csw(struct cdev *dev, struct cdevsw *csw, struct buf *bp); struct cdev *make_dev(struct cdevsw *_devsw, int _unit, uid_t _uid, gid_t _gid, int _perms, const char *_fmt, ...) __printflike(6, 7); struct cdev *make_dev_cred(struct cdevsw *_devsw, int _unit,