freebsd-nq/share/man/man9/SPLASSERT.9

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.Dd January 14, 2000
.Os
.Dt SPLASSERT 9
.Sh NAME
.Nm SPLASSERT
.Nd kernel spl level verification macro
.Sh SYNOPSIS
.Cd options INVARIANTS
.Cd options INVARIANT_SUPPORT
.Fn SPLASSERT level "const char *msg"
.Sh DESCRIPTION
.Bf -symbolic
This API is deprecated.
Use mutexes to protect data structures instead.
See
.Xr mutex 9
for more information.
.Ef
.Pp
In a kernel compiled with both "options INVARIANTS"
and "options INVARIANT_SUPPORT",
the
.Fn SPLASSERT
macro compares the current spl level of the kernel with the spl
.Fa level
specified in the macro
.Fn SPLASSERT .
If the specified
.Fa level
is not active
.Fn SPLASSERT
calls the
.Fn KASSERT
macro with the
.Fa msg ,
terminating the running system.
.Pp
In a kernel that does not have both "options INVARIANTS"
and "options INVARIANT_SUPPORT",
the
.Fn SPLASSERT
macro is defined to be a no-op.
.Pp
The behaviour of
.Fn SPLASSERT
is tunable by means of the
.Xr sysctl 8
knob kern.splassertmode.
When set to 0 the
.Fn SPLASSERT
macro is defined to be a no-op.
When set to 1 the
.Fn SPLASSERT
macro is defined to log information to the console.
When set to 2 the
.Fn SPLASSERT
macro is defined to
.Xr panic 9 .
.Sh EXAMPLES
The kernel function
.Fn rtalloc
must be called at
.Fn splnet :
.Bd -literal -offset indent
void
rtalloc(ro)
	register struct route *ro;
{
	SPLASSERT(net, "rtalloc()");
	rtalloc_ign(ro, 0UL);
}
.Ed
.Pp
.Sh SEE ALSO
.Xr config 8 ,
.Xr CONDSPLASSERT 9 ,
.Xr KASSERT 9 ,
.Xr panic 9
.Sh AUTHORS
This manual page was written by
.An Jonathan M. Bresler
.Aq jmb@FreeBSD.org .