From 50efccc9f04a04f03e963eee6a0f24acb1b0cec9 Mon Sep 17 00:00:00 2001 From: ed Date: Wed, 28 Jan 2009 19:58:05 +0000 Subject: Mark most often used sysctl's as MPSAFE. After running a `make buildkernel', I noticed most of the Giant locks in sysctl are only caused by a very small amount of sysctl's: - sysctl.name2oid. This one is locked by SYSCTL_LOCK, just like sysctl.oidfmt. - kern.ident, kern.osrelease, kern.version, etc. These are just constant strings. - kern.arandom, used by the stack protector. It is already protected by arc4_mtx. I also saw the following sysctl's show up. Not as often as the ones above, but still quite often: - security.jail.jailed. Also mark security.jail.list as MPSAFE. They don't need locking or already use allprison_lock. - kern.devname, used by devname(3), ttyname(3), etc. This seems to reduce Giant locking inside sysctl by ~75% in my primitive test setup. --- sys/kern/kern_jail.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'sys/kern/kern_jail.c') diff --git a/sys/kern/kern_jail.c b/sys/kern/kern_jail.c index e4342ad..b87de0b 100644 --- a/sys/kern/kern_jail.c +++ b/sys/kern/kern_jail.c @@ -1529,8 +1529,9 @@ sysctl_jail_list(SYSCTL_HANDLER_ARGS) return (error); } -SYSCTL_OID(_security_jail, OID_AUTO, list, CTLTYPE_STRUCT | CTLFLAG_RD, - NULL, 0, sysctl_jail_list, "S", "List of active jails"); +SYSCTL_OID(_security_jail, OID_AUTO, list, + CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, + sysctl_jail_list, "S", "List of active jails"); static int sysctl_jail_jailed(SYSCTL_HANDLER_ARGS) @@ -1542,8 +1543,9 @@ sysctl_jail_jailed(SYSCTL_HANDLER_ARGS) return (error); } -SYSCTL_PROC(_security_jail, OID_AUTO, jailed, CTLTYPE_INT | CTLFLAG_RD, - NULL, 0, sysctl_jail_jailed, "I", "Process in jail?"); +SYSCTL_PROC(_security_jail, OID_AUTO, jailed, + CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, + sysctl_jail_jailed, "I", "Process in jail?"); #ifdef DDB DB_SHOW_COMMAND(jails, db_show_jails) -- cgit v1.1