Do some minor Giant pushdown made possible by copyin, fget, fdrop,

malloc and mbuf allocation all not requiring Giant.

1) ostat, fstat and nfstat don't need Giant until they call fo_stat.
2) accept can copyin the address length without grabbing Giant.
3) sendit doesn't need Giant, so don't bother grabbing it until kern_sendit.
4) move Giant grabbing from each indivitual recv* syscall to recvit.

1 files changed, 6 insertions, 6 deletions

diff --git a/sys/kern/kern_descrip.c b/sys/kern/kern_descrip.c
index be1a30f..c2a6eea 100644
--- a/sys/kern/kern_descrip.c
+++ b/sys/kern/kern_descrip.c
@@ -900,17 +900,17 @@ ofstat(td, uap)
 	struct ostat oub;
 	int error;
 
-	mtx_lock(&Giant);
 	if ((error = fget(td, uap->fd, &fp)) != 0)
 		goto done2;
+	mtx_lock(&Giant);
 	error = fo_stat(fp, &ub, td->td_ucred, td);
+	mtx_unlock(&Giant);
 	if (error == 0) {
 		cvtstat(&ub, &oub);
 		error = copyout(&oub, uap->sb, sizeof(oub));
 	}
 	fdrop(fp, td);
 done2:
-	mtx_unlock(&Giant);
 	return (error);
 }
 #endif /* COMPAT_43 || COMPAT_SUNOS */
@@ -937,15 +937,15 @@ fstat(td, uap)
 	struct stat ub;
 	int error;
 
-	mtx_lock(&Giant);
 	if ((error = fget(td, uap->fd, &fp)) != 0)
 		goto done2;
+	mtx_lock(&Giant);
 	error = fo_stat(fp, &ub, td->td_ucred, td);
+	mtx_unlock(&Giant);
 	if (error == 0)
 		error = copyout(&ub, uap->sb, sizeof(ub));
 	fdrop(fp, td);
 done2:
-	mtx_unlock(&Giant);
 	return (error);
 }
 
@@ -972,17 +972,17 @@ nfstat(td, uap)
 	struct nstat nub;
 	int error;
 
-	mtx_lock(&Giant);
 	if ((error = fget(td, uap->fd, &fp)) != 0)
 		goto done2;
+	mtx_lock(&Giant);
 	error = fo_stat(fp, &ub, td->td_ucred, td);
+	mtx_unlock(&Giant);
 	if (error == 0) {
 		cvtnstat(&ub, &nub);
 		error = copyout(&nub, uap->sb, sizeof(nub));
 	}
 	fdrop(fp, td);
 done2:
-	mtx_unlock(&Giant);
 	return (error);
 }