From owner-freebsd-stable@FreeBSD.ORG Tue Jun 1 17:05:32 2010 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 8177A106566C; Tue, 1 Jun 2010 17:05:32 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from mail.zoral.com.ua (mx0.zoral.com.ua [91.193.166.200]) by mx1.freebsd.org (Postfix) with ESMTP id C00ED8FC08; Tue, 1 Jun 2010 17:05:31 +0000 (UTC) Received: from deviant.kiev.zoral.com.ua (root@deviant.kiev.zoral.com.ua [10.1.1.148]) by mail.zoral.com.ua (8.14.2/8.14.2) with ESMTP id o51H5eDd089021 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Tue, 1 Jun 2010 20:05:40 +0300 (EEST) (envelope-from kostikbel@gmail.com) Received: from deviant.kiev.zoral.com.ua (kostik@localhost [127.0.0.1]) by deviant.kiev.zoral.com.ua (8.14.4/8.14.4) with ESMTP id o51H5Qg1048913; Tue, 1 Jun 2010 20:05:26 +0300 (EEST) (envelope-from kostikbel@gmail.com) Received: (from kostik@localhost) by deviant.kiev.zoral.com.ua (8.14.4/8.14.4/Submit) id o51H5QFN048912; Tue, 1 Jun 2010 20:05:26 +0300 (EEST) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: deviant.kiev.zoral.com.ua: kostik set sender to kostikbel@gmail.com using -f Date: Tue, 1 Jun 2010 20:05:26 +0300 From: Kostik Belousov To: John Baldwin Message-ID: <20100601170526.GJ83316@deviant.kiev.zoral.com.ua> References: <20100530143034.GH43302@hades.panopticon> <20100530150622.GJ83316@deviant.kiev.zoral.com.ua> <201006011141.09699.jhb@freebsd.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="zruoG3PDhkeTLwq7" Content-Disposition: inline In-Reply-To: <201006011141.09699.jhb@freebsd.org> User-Agent: Mutt/1.4.2.3i X-Virus-Scanned: clamav-milter 0.95.2 at skuns.kiev.zoral.com.ua X-Virus-Status: Clean X-Spam-Status: No, score=-2.4 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_50, DNS_FROM_OPENWHOIS autolearn=no version=3.2.5 X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on skuns.kiev.zoral.com.ua Cc: freebsd-current@freebsd.org, freebsd-stable@freebsd.org, Dmitry Marakasov Subject: Re: need better POSIX semaphore support X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 01 Jun 2010 17:05:32 -0000 --zruoG3PDhkeTLwq7 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Jun 01, 2010 at 11:41:09AM -0400, John Baldwin wrote: > On Sunday 30 May 2010 11:06:22 am Kostik Belousov wrote: > > On Sun, May 30, 2010 at 06:30:35PM +0400, Dmitry Marakasov wrote: > > > Hi! > > >=20 > > > Not long ago, POSIX semaphores support was enabled by default as it's > > > becoming more widely used, by e.g. firefox. However, the support > > > for these is still incomplete: we only have systemwide limit of 30 > > > semaphores, and that doesn't seem to be configurable neither online w= ith > > > sysctl, nor at boottime from loader.conf. I only was able to raise > > > semaphore count by changing SEM_MAX in kernel sources. > > >=20 > > > The real appliaction which needs more semaphores is lightspark > > > (graphics/lightspark-devel) flash plugin - it uses ~40 sems for simple > > > clips and ~250 for something like youtube videos. > > >=20 > > > Until there more apps that require proper semaphore support, I guess > > > we need to improve it asap. Given the amount of memory used by ksem, > > > the least can be done is SEM_MAX bumped up to 5120 or so for > > > non-embedded kernels. 5120 semaphores require just 644k of kernel > > > memory (judging by vmstat), and is "ought to be enough for anybody". > > > Another good thing would be to make it configurable at boot-time > > > or even better in runtime. > >=20 > > HEAD contains different implementation. Apparently, it did not made > > into stable/8 yet, so it will not appear in the 8.1. >=20 > The one thing I don't like about this approach is you can write the > variable even when sem.ko isn't loaded. The SEM_* values should really > only exist when sem.ko is loaded I think, which requires moving them > into uipc_sem.c. I think the values should exist always, because sysconf(3) returns error (i.e. -1 and errno set) when sysctl fails. sysconf(3) interprets 0 result as "feature not supported". I modified the patch to only allow change of value when the module is loade= d. Also, the module unload now clears mib. As usual, module unload races are not handled. diff --git a/sys/kern/posix4_mib.c b/sys/kern/posix4_mib.c index 5242b31..cbe140d 100644 --- a/sys/kern/posix4_mib.c +++ b/sys/kern/posix4_mib.c @@ -45,6 +45,8 @@ __FBSDID("$FreeBSD$"); static int facility[CTL_P1003_1B_MAXID - 1]; static int facility_initialized[CTL_P1003_1B_MAXID - 1]; =20 +static int p31b_sysctl_proc(SYSCTL_HANDLER_ARGS); + /* OID_AUTO isn't working with sysconf(3). I guess I'd have to * modify it to do a lookup by name from the index. * For now I've left it a top-level sysctl. @@ -55,16 +57,21 @@ static int facility_initialized[CTL_P1003_1B_MAXID - 1]; SYSCTL_DECL(_p1003_1b); =20 #define P1B_SYSCTL(num, name) \ -SYSCTL_INT(_p1003_1b, num, \ - name, CTLFLAG_RD, facility + num - 1, 0, ""); + SYSCTL_INT(_p1003_1b, num, name, CTLFLAG_RD, facility + num - 1, 0, ""); +#define P1B_SYSCTL_RW(num, name) \ + SYSCTL_PROC(_p1003_1b, num, name, CTLTYPE_INT | CTLFLAG_RW, NULL, num, \ + p31b_sysctl_proc, "I", ""); =20 #else =20 SYSCTL_DECL(_kern_p1003_1b); =20 #define P1B_SYSCTL(num, name) \ -SYSCTL_INT(_kern_p1003_1b, OID_AUTO, \ - name, CTLFLAG_RD, facility + num - 1, 0, ""); + SYSCTL_INT(_kern_p1003_1b, OID_AUTO, name, CTLFLAG_RD, \ + facility + num - 1, 0, ""); +#define P1B_SYSCTL_RW(num, name) \ + SYSCTL_PROC(_p1003_1b, OID_AUTO, name, CTLTYPE_INT | CTLFLAG_RW, NULL, \ + num, p31b_sysctl_proc, "I", ""); SYSCTL_NODE(_kern, OID_AUTO, p1003_1b, CTLFLAG_RW, 0, "P1003.1B"); =20 #endif @@ -91,13 +98,28 @@ P1B_SYSCTL(CTL_P1003_1B_DELAYTIMER_MAX, delaytimer_max); P1B_SYSCTL(CTL_P1003_1B_MQ_OPEN_MAX, mq_open_max); P1B_SYSCTL(CTL_P1003_1B_PAGESIZE, pagesize); P1B_SYSCTL(CTL_P1003_1B_RTSIG_MAX, rtsig_max); -P1B_SYSCTL(CTL_P1003_1B_SEM_NSEMS_MAX, sem_nsems_max); +P1B_SYSCTL_RW(CTL_P1003_1B_SEM_NSEMS_MAX, sem_nsems_max); P1B_SYSCTL(CTL_P1003_1B_SEM_VALUE_MAX, sem_value_max); P1B_SYSCTL(CTL_P1003_1B_SIGQUEUE_MAX, sigqueue_max); P1B_SYSCTL(CTL_P1003_1B_TIMER_MAX, timer_max); =20 #define P31B_VALID(num) ((num) >=3D 1 && (num) < CTL_P1003_1B_MAXID) =20 +static int +p31b_sysctl_proc(SYSCTL_HANDLER_ARGS) +{ + int error, num, val; + + num =3D arg2; + if (!P31B_VALID(num)) + return (EINVAL); + val =3D facility_initialized[num] ? facility[num - 1] : 0; + error =3D sysctl_handle_int(oidp, &val, 0, req); + if (error =3D=3D 0 && req->newptr !=3D NULL && facility_initialized[num]) + facility[num - 1] =3D val; + return (error); +} + /* p31b_setcfg: Set the configuration */ void @@ -110,6 +132,14 @@ p31b_setcfg(int num, int value) } } =20 +void +p31b_unsetcfg(int num) +{ + + facility[num - 1] =3D 0; + facility_initialized[num -1] =3D 0; +} + int p31b_getcfg(int num) { diff --git a/sys/kern/uipc_sem.c b/sys/kern/uipc_sem.c index d9229ea..0b8f132 100644 --- a/sys/kern/uipc_sem.c +++ b/sys/kern/uipc_sem.c @@ -976,6 +976,8 @@ ksem_module_destroy(void) sx_destroy(&ksem_dict_lock); mtx_destroy(&ksem_count_lock); mtx_destroy(&sem_lock); + p31b_unsetcfg(CTL_P1003_1B_SEM_VALUE_MAX); + p31b_unsetcfg(CTL_P1003_1B_SEM_NSEMS_MAX); } =20 static int diff --git a/sys/sys/posix4.h b/sys/sys/posix4.h index ea379c0..34f77f4 100644 --- a/sys/sys/posix4.h +++ b/sys/sys/posix4.h @@ -64,6 +64,7 @@ int p31b_proc(struct proc *, pid_t, struct proc **); void p31b_setcfg(int, int); int p31b_getcfg(int); int p31b_iscfg(int); +void p31b_unsetcfg(int); =20 #ifdef _KPOSIX_PRIORITY_SCHEDULING =20 --zruoG3PDhkeTLwq7 Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (FreeBSD) iEYEARECAAYFAkwFPdYACgkQC3+MBN1Mb4icFwCeLtYMI7m6kuZ5t9X8YNFEg8dQ 7FkAn24sDS1zePA7HC5oDcgQ3cP3Gbu3 =T0aL -----END PGP SIGNATURE----- --zruoG3PDhkeTLwq7--