diff options
| author | Kirk McKusick <mckusick@FreeBSD.org> | 2002-10-22 00:59:49 +0000 |
|---|---|---|
| committer | Kirk McKusick <mckusick@FreeBSD.org> | 2002-10-22 00:59:49 +0000 |
| commit | e03486d198aca9b5461b5d97e2ab1e39c90341cf (patch) | |
| tree | 361adeff047bd5410b29dbc5d86cfa78bd68675e /sys/fs | |
| parent | 52d0ed1d0d2a3962fdaef086020ca1d7aacc5c74 (diff) | |
Notes
Diffstat (limited to 'sys/fs')
| -rw-r--r-- | sys/fs/specfs/spec_vnops.c | 25 |
1 files changed, 24 insertions, 1 deletions
diff --git a/sys/fs/specfs/spec_vnops.c b/sys/fs/specfs/spec_vnops.c index 51c279220609b..9ae87c059789b 100644 --- a/sys/fs/specfs/spec_vnops.c +++ b/sys/fs/specfs/spec_vnops.c @@ -40,6 +40,7 @@ #include <sys/proc.h> #include <sys/systm.h> #include <sys/kernel.h> +#include <sys/mutex.h> #include <sys/conf.h> #include <sys/bio.h> #include <sys/buf.h> @@ -493,6 +494,18 @@ loop2: } /* + * Mutex to use when delaying niced I/O bound processes in spec_strategy(). + */ +static struct mtx strategy_mtx; +static void +strategy_init(void) +{ + + mtx_init(&strategy_mtx, "strategy", NULL, MTX_DEF); +} +SYSINIT(strategy, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, strategy_init, NULL) + +/* * Just call the device strategy routine */ static int @@ -507,7 +520,17 @@ spec_strategy(ap) struct mount *mp; int error; struct cdevsw *dsw; - + struct thread *td = curthread; + + /* + * Slow down disk requests for niced processes. + */ + if (td && td->td_ksegrp->kg_nice > 0) { + mtx_lock(&strategy_mtx); + msleep(&strategy_mtx, &strategy_mtx, + PPAUSE | PCATCH | PDROP, "ioslow", + td->td_ksegrp->kg_nice); + } bp = ap->a_bp; vp = ap->a_vp; if (bp->b_iocmd == BIO_WRITE) { |