So far all common tc atttributes were accessed via specific functions, i.e.
rtnl_class_set_parent(), rtnl_qdisc_set_parent(), rtnl_cls_set_parent()
which implied a lot of code duplication. Since all tc objects are derived
from struct rtnl_tc and these common attributes are already stored in there
this patch removes all type specific functions and makes rtnl_tc_* attribute
functions public.
rtnl_qdisc_set_parent(qdisc, 10);
becomes:
rtnl_tc_set_parent((struct rtnl_tc *) qdisc, 10);
This patch also adds the following new attributes to tc objects therefore
removing them as tc specific attributes:
- mtu
- mpu
- overhead
This allows for the rate table calculations to be unified as well taking into
account the new kernel behavior to take care of overhead automatically.
Without this patch, running alloc / free cache loop will lead to huge memory
leaks on machine with 3000 interfaces with tbf qdiscs.
Here was valgrind output:
==5580== 18,070,728 bytes in 347,514 blocks are definitely lost in loss record
32 of 32
==5580== at 0x4025485: calloc (in /lib/valgrind/vgpreload_memcheck-x86-
linux.so)
==5580== by 0x405F410: tbf_msg_parser (tbf.c:46)
==5580== by 0x405302B: qdisc_msg_parser (qdisc.c:119)
==5580== by 0x4033DC9: nl_cache_parse (cache.c:643)
==5580== by 0x4033E7C: update_msg_parser (cache.c:460)
==5580== by 0x4038A11: nl_recvmsgs (netlink-local.h:112)
==5580== by 0x4034175: __cache_pickup (cache.c:483)
==5580== by 0x40343FF: nl_cache_pickup (cache.c:516)
==5580== by 0x403447D: nl_cache_refill (cache.c:698)
==5580== by 0x4034AB7: nl_cache_alloc_and_fill (cache.c:198)
==5580== by 0x4053216: rtnl_qdisc_alloc_cache (qdisc.c:388)
==5580== by 0x80489DB: main (in /home/root/nltest)
Patch complied and tested for same test case, no more leaks anymore.
In order for the interface to become more thread safe, the error
handling was revised to no longer depend on a static errno and
error string buffer.
This patch converts all error paths to return a libnl specific
error code which can be translated to a error message using
nl_geterror(int error). The functions nl_error() and
nl_get_errno() are therefore obsolete.
This change required various sets of function prototypes to be
changed in order to return an error code, the most prominent
are:
struct nl_cache *foo_alloc_cache(...);
changed to:
int foo_alloc_cache(..., struct nl_cache **);
struct nl_msg *foo_build_request(...);
changed to:
int foo_build_request(..., struct nl_msg **);
struct foo *foo_parse(...);
changed to:
int foo_parse(..., struct foo **);
This pretty much only leaves trivial allocation functions to
still return a pointer object which can still return NULL to
signal out of memory.
This change is a serious API and ABI breaker, sorry!
New netem-related functionality:
Added ability to save new settings to the kernel. In netem.c, the
netem_get_opts() stub has been replaced with netem_build_msg() which
manipulates the nl_msg data directly and returns an error code instead
of a new nl_msg. Modifications to qdisc_build() in qdisc.c and struct
rtnl_qdisc_ops were necessary for this.
Added support for getting/setting corruption probability/correlation.
Added support for setting a delay distribution.
Fixed tbf_msg_parser() to call tbf_alloc() instead of tbf_qdisc() to
prevent a seg fault.
