Tracepoint does not add value and the call to fib_lookup follows
it which shows the same information and the fib lookup result.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit bb0ad1987e ("ipv6: fib6_rules: support for match on sport, dport
and ip proto") added support for protocol and ports to FIB rules.
Update the FIB lookup tracepoint to dump the parameters.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 4a2d73a4fb ("ipv4: fib_rules: support match on sport, dport
and ip proto") added support for protocol and ports to FIB rules.
Update the FIB lookup tracepoint to dump the parameters.
In addition, make the IPv4 tracepoint similar to the IPv6 one where
the lookup parameters and result are dumped in 1 event. It is much
easier to use and understand the outcome of the lookup.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 05f0fe6b74 ("RCU, workqueue: Implement rcu_work") introduces
new API's for dispatching work in a RCU callback. Now we can just
switch to the new API's for tc filters. This could get rid of a lot
of code.
Cc: Tejun Heo <tj@kernel.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The PPPIOCDETACH ioctl effectively tries to "close" the given ppp file
before f_count has reached 0, which is fundamentally a bad idea. It
does check 'f_count < 2', which excludes concurrent operations on the
file since they would only be possible with a shared fd table, in which
case each fdget() would take a file reference. However, it fails to
account for the fact that even with 'f_count == 1' the file can still be
linked into epoll instances. As reported by syzbot, this can trivially
be used to cause a use-after-free.
Yet, the only known user of PPPIOCDETACH is pppd versions older than
ppp-2.4.2, which was released almost 15 years ago (November 2003).
Also, PPPIOCDETACH apparently stopped working reliably at around the
same time, when the f_count check was added to the kernel, e.g. see
https://lkml.org/lkml/2002/12/31/83. Also, the current 'f_count < 2'
check makes PPPIOCDETACH only work in single-threaded applications; it
always fails if called from a multithreaded application.
All pppd versions released in the last 15 years just close() the file
descriptor instead.
Therefore, instead of hacking around this bug by exporting epoll
internals to modules, and probably missing other related bugs, just
remove the PPPIOCDETACH ioctl and see if anyone actually notices. Leave
a stub in place that prints a one-time warning and returns EINVAL.
Reported-by: syzbot+16363c99d4134717c05b@syzkaller.appspotmail.com
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
Reviewed-by: Guillaume Nault <g.nault@alphalink.fr>
Tested-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Petr Machata says:
====================
Mirroring tests involving VLAN
This patchset tests mirror-to-gretap with various underlay
configurations involving VLAN netdevice in particular. Some of the tests
involve bridges as well, but tests aimed specifically at testing bridges
(i.e. FDB, STP) are not part of this patchset.
In patches #1-#6, the codebase is adapted to support the new tests.
In patch #7, a test for mirroring to VLAN is introduced.
Patches #8-#10 add three tests where VLAN is part of underlay path after
gretap encapsulation.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Test for "tc action mirred egress mirror" that mirrors to GRE when the
underlay route points at an 802.1d bridge and packet egresses through a
VLAN device.
Besides testing basic connectivity, this also tests that the traffic is
properly tagged.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Test for "tc action mirred egress mirror" that mirrors to a gretap
netdevice whose underlay route points at a vlan device.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Test for "tc action mirred egress mirror" that mirrors to GRE when the
underlay route points at a vlan device on top of a bridge device with
vlan filtering (802.1q).
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Test for "tc action mirred egress mirror" that mirrors to a vlan device.
- test_vlan() tests that the packets get mirrored
- test_tagged_vlan() tests that the mirrored packets have correct inner
VLAN tag.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A mirror-to-vlan test that's coming next needs to install the trap
unconditionally. Therefore extract from slow_path_trap_{,un}install()
a more generic functions trap_install() and trap_uninstall(), and covert
the former two to conditional wrappers around these.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add full_test_span_gre_dir_vlan_ips() and full_test_span_gre_dir_vlan()
to support mirror-to-gre tests that involve VLAN.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add vlan_create() and vlan_destroy() to manage VLAN netdevices.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Having a clsact qdisc on $h3 is useful in several tests, and will be
useful in more tests to come. Move the registration from all the tests
that need it into the topology file itself.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For non-GRE mirroring tests, a functions along the lines of
do_test_span_gre_dir_ips() and test_span_gre_dir_ips() are necessary,
but such that they don't assume tunnels are involved. Extract the code
from mirror_gre_lib.sh to mirror_lib.sh and convert to just use a given
device without assuming it's named "h3-$tundev". Convert the two
above-mentioned functions to wrappers that pass along the correct device
name.
Add test_span_dir() and fail_test_span_dir() to round up the API for use
by following patches.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move generic parts of mirror_gre_topo_lib.sh into a new file
mirror_topo_lib.sh. Reuse the functions in GRE topo, adding the tunnel
devices as necessary.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov says:
====================
pull-request: bpf-next 2018-05-24
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) Björn Töpel cleans up AF_XDP (removes rebind, explicit cache alignment from uapi, etc).
2) David Ahern adds mtu checks to bpf_ipv{4,6}_fib_lookup() helpers.
3) Jesper Dangaard Brouer adds bulking support to ndo_xdp_xmit.
4) Jiong Wang adds support for indirect and arithmetic shifts to NFP
5) Martin KaFai Lau cleans up BTF uapi and makes the btf_header extensible.
6) Mathieu Xhonneux adds an End.BPF action to seg6local with BPF helpers allowing
to edit/grow/shrink a SRH and apply on a packet generic SRv6 actions.
7) Sandipan Das adds support for bpf2bpf function calls in ppc64 JIT.
8) Yonghong Song adds BPF_TASK_FD_QUERY command for introspection of tracing events.
9) other misc fixes from Gustavo A. R. Silva, Sirio Balmelli, John Fastabend, and Magnus Karlsson
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Thomas Falcon says:
====================
ibmvnic: Failover hardening
Introduce additional transport event hardening to handle
events during device reset. In the driver's current state,
if a transport event is received during device reset, it can
cause the device to become unresponsive as invalid operations
are processed as the backing device context changes. After
a transport event, the device expects a request to begin the
initialization process. If the driver is still processing
a previously queued device reset in this state, it is likely
to fail as firmware will reject any commands other than the
one to initialize the client driver's Command-Response Queue.
Instead of failing and becoming dormant, the driver will make
one more attempt to recover and continue operation. This is
achieved by setting a state flag, which if true will direct
the driver to clean up all allocated resources and perform
a hard reset in an attempt to bring the driver back to an
operational state.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce a recovery hard reset to handle reset failure as a result of
change of device context following a transport event, such as a
backing device failover or partition migration. These operations reset
the device context to its initial state. If this occurs during a reset,
any initialization commands are likely to fail with an invalid state
error as backing device firmware requests reinitialization.
When this happens, make one more attempt by performing a hard reset,
which frees any resources currently allocated and performs device
initialization. If a transport event occurs during a device reset, a
flag is set which will trigger a new hard reset following the
completionof the current reset event.
Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Set device resetting state at the earliest possible point: as soon as a
reset is successfully scheduled. The reset state is toggled off when
all resets have been processed to completion.
Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of having one initialization routine for all cases, create
a separate, simpler function for standard initialization, such as during
device probe. Use the original initialization function to handle
device reset scenarios. The goal of this patch is to avoid having
a single, cluttered init function to handle all possible
scenarios.
Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If setting the link state is not successful, print a warning
with the resulting return code and return it to be handled
by the caller.
Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If device init is interrupted by a failover, set the init return
code so that it can be checked and handled appropriately by the
init routine.
Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Check whether CRQ command is successful before awaiting a response
from the management partition. If the command was not successful, the
driver may hang waiting for a response that will never come.
Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce an "active" state for a IBM vNIC Command-Response Queue. A CRQ
is considered active once it has initialized or linked with its partner by
sending an initialization request and getting a successful response back
from the management partition. Until this has happened, do not allow CRQ
commands to be sent other than the initialization request.
This change will avoid a protocol error in case of a device transport
event occurring during a initialization. When the driver receives a
transport event notification indicating that the backing hardware
has changed and needs reinitialization, any further commands other
than the initialization handshake with the VIOS management partition
will result in an invalid state error. Instead of sending a command
that will be returned with an error, print a warning and return an
error that will be handled by the caller.
Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Set adapter NAPI state as disabled if they are removed. This will allow
them to be enabled again if reallocated in case of a hard reset.
Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A precondition check in ip_recv_error triggered on an otherwise benign
race. Remove the warning.
The warning triggers when passing an ipv6 socket to this ipv4 error
handling function. RaceFuzzer was able to trigger it due to a race
in setsockopt IPV6_ADDRFORM.
---
CPU0
do_ipv6_setsockopt
sk->sk_socket->ops = &inet_dgram_ops;
---
CPU1
sk->sk_prot->recvmsg
udp_recvmsg
ip_recv_error
WARN_ON_ONCE(sk->sk_family == AF_INET6);
---
CPU0
do_ipv6_setsockopt
sk->sk_family = PF_INET;
This socket option converts a v6 socket that is connected to a v4 peer
to an v4 socket. It updates the socket on the fly, changing fields in
sk as well as other structs. This is inherently non-atomic. It races
with the lockless udp_recvmsg path.
No other code makes an assumption that these fields are updated
atomically. It is benign here, too, as ip_recv_error cares only about
the protocol of the skbs enqueued on the error queue, for which
sk_family is not a precise predictor (thanks to another isue with
IPV6_ADDRFORM).
Link: http://lkml.kernel.org/r/20180518120826.GA19515@dragonet.kaist.ac.kr
Fixes: 7ce875e5ec ("ipv4: warn once on passing AF_INET6 socket to ip_recv_error")
Reported-by: DaeRyong Jeong <threeearcat@gmail.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Petr Machata says:
====================
selftests: forwarding: Additions to mirror-to-gretap tests
This patchset is for a handful of edge cases in mirror-to-gretap
scenarios: removal of mirrored-to netdevice (#1), removal of underlay
route for tunnel remote endpoint (#2) and cessation of mirroring upon
removal of flower mirroring rule (#3).
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Test that when flower-based mirror action is removed, mirroring stops.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When underlay route is removed, the mirrored traffic should not be
forwarded.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tests that the mirroring code catches up with deletion of a mirrored-to
device.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When dealing with ingress rule on a netdev, if we did fine through the
conventional path, there's no need to continue into the egdev route,
and we can stop right there.
Not doing so may cause a 2nd rule to be added by the cls api layer
with the ingress being the egdev.
For example, under sriov switchdev scheme, a user rule of VFR A --> VFR B
will end up with two HW rules (1) VF A --> VF B and (2) uplink --> VF B
Fixes: 208c0f4b52 ('net: sched: use tc_setup_cb_call to call per-block callbacks')
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
DaeRyong Jeong reports a race between vhost_dev_cleanup() and
vhost_process_iotlb_msg():
Thread interleaving:
CPU0 (vhost_process_iotlb_msg) CPU1 (vhost_dev_cleanup)
(In the case of both VHOST_IOTLB_UPDATE and
VHOST_IOTLB_INVALIDATE)
===== =====
vhost_umem_clean(dev->iotlb);
if (!dev->iotlb) {
ret = -EFAULT;
break;
}
dev->iotlb = NULL;
The reason is we don't synchronize between them, fixing by protecting
vhost_process_iotlb_msg() with dev mutex.
Reported-by: DaeRyong Jeong <threeearcat@gmail.com>
Fixes: 6b1e6cc785 ("vhost: new device IOTLB API")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Merge tag 'mlx5-fixes-2018-05-24' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux
Saeed Mahameed says:
====================
Mellanox, mlx5 fixes 2018-05-24
This series includes two mlx5 fixes.
1) add FCS data to checksum complete when required, from Eran Ben
Elisha.
2) Fix A race in IPSec sandbox QP commands, from Yossi Kuperman.
Please pull and let me know if there's any problem.
for -stable v4.15
("net/mlx5e: When RXFCS is set, add FCS data into checksum calculation")
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit b84bbaf7a6 ("packet: in packet_snd start writing at link
layer allocation") ensures that packet_snd always starts writing
the link layer header in reserved headroom allocated for this
purpose.
This is needed because packets may be shorter than hard_header_len,
in which case the space up to hard_header_len may be zeroed. But
that necessary padding is not accounted for in skb->len.
The fix, however, is buggy. It calls skb_push, which grows skb->len
when moving skb->data back. But in this case packet length should not
change.
Instead, call skb_reserve, which moves both skb->data and skb->tail
back, without changing length.
Fixes: b84bbaf7a6 ("packet: in packet_snd start writing at link layer allocation")
Reported-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
t4_prep_fw doesn't check for card_fw pointer before store the read data,
which could lead to a NULL pointer dereference if kvzalloc failed.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jesper Dangaard Brouer says:
====================
This patchset change ndo_xdp_xmit API to take a bulk of xdp frames.
When kernel is compiled with CONFIG_RETPOLINE, every indirect function
pointer (branch) call hurts performance. For XDP this have a huge
negative performance impact.
This patchset reduce the needed (indirect) calls to ndo_xdp_xmit, but
also prepares for further optimizations. The DMA APIs use of indirect
function pointer calls is the primary source the regression. It is
left for a followup patchset, to use bulking calls towards the DMA API
(via the scatter-gatter calls).
The other advantage of this API change is that drivers can easier
amortize the cost of any sync/locking scheme, over the bulk of
packets. The assumption of the current API is that the driver
implemementing the NDO will also allocate a dedicated XDP TX queue for
every CPU in the system. Which is not always possible or practical to
configure. E.g. ixgbe cannot load an XDP program on a machine with
more than 96 CPUs, due to limited hardware TX queues. E.g. virtio_net
is hard to configure as it requires manually increasing the
queues. E.g. tun driver chooses to use a per XDP frame producer lock
modulo smp_processor_id over avail queues.
I'm considered adding 'flags' to ndo_xdp_xmit, but it's not part of
this patchset. This will be a followup patchset, once we know if this
will be needed (e.g. for non-map xdp_redirect flush-flag, and if
AF_XDP chooses to use ndo_xdp_xmit for TX).
---
V5: Fixed up issues spotted by Daniel and John
V4: Splitout the patches from 4 to 8 patches. I cannot split the
driver changes from the NDO change, but I've tried to isolated the NDO
change together with the driver change as much as possible.
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Update xdp_monitor to use the recently added err code introduced
in tracepoint xdp:xdp_devmap_xmit, to show if the drop count is
caused by some driver general delivery problem. Other kind of drops
will likely just be more normal TX space issues.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Extending tracepoint xdp:xdp_devmap_xmit in devmap with an err code
allow people to easier identify the reason behind the ndo_xdp_xmit
call to a given driver is failing.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch change the API for ndo_xdp_xmit to support bulking
xdp_frames.
When kernel is compiled with CONFIG_RETPOLINE, XDP sees a huge slowdown.
Most of the slowdown is caused by DMA API indirect function calls, but
also the net_device->ndo_xdp_xmit() call.
Benchmarked patch with CONFIG_RETPOLINE, using xdp_redirect_map with
single flow/core test (CPU E5-1650 v4 @ 3.60GHz), showed
performance improved:
for driver ixgbe: 6,042,682 pps -> 6,853,768 pps = +811,086 pps
for driver i40e : 6,187,169 pps -> 6,724,519 pps = +537,350 pps
With frames avail as a bulk inside the driver ndo_xdp_xmit call,
further optimizations are possible, like bulk DMA-mapping for TX.
Testing without CONFIG_RETPOLINE show the same performance for
physical NIC drivers.
The virtual NIC driver tun sees a huge performance boost, as it can
avoid doing per frame producer locking, but instead amortize the
locking cost over the bulk.
V2: Fix compile errors reported by kbuild test robot <lkp@intel.com>
V4: Isolated ndo, driver changes and callers.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
When sending an xdp_frame through xdp_do_redirect call, then error
cases can happen where the xdp_frame needs to be dropped, and
returning an -errno code isn't sufficient/possible any-longer
(e.g. for cpumap case). This is already fully supported, by simply
calling xdp_return_frame.
This patch is an optimization, which provides xdp_return_frame_rx_napi,
which is a faster variant for these error cases. It take advantage of
the protection provided by XDP RX running under NAPI protection.
This change is mostly relevant for drivers using the page_pool
allocator as it can take advantage of this. (Tested with mlx5).
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The xdp_monitor sample/tool is updated to use the new tracepoint
xdp:xdp_devmap_xmit the previous patch just introduced.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Notice how this allow us get XDP statistic without affecting the XDP
performance, as tracepoint is no-longer activated on a per packet basis.
V5: Spotted by John Fastabend.
Fix 'sent' also counted 'drops' in this patch, a later patch corrected
this, but it was a mistake in this intermediate step.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Like cpumap create queue for xdp frames that will be bulked. For now,
this patch simply invoke ndo_xdp_xmit foreach frame. This happens,
either when the map flush operation is envoked, or when the limit
DEV_MAP_BULK_SIZE is reached.
V5: Avoid memleak on error path in dev_map_update_elem()
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Functionality is the same, but the ndo_xdp_xmit call is now
simply invoked from inside the devmap.c code.
V2: Fix compile issue reported by kbuild test robot <lkp@intel.com>
V5: Cleanups requested by Daniel
- Newlines before func definition
- Use BUILD_BUG_ON checks
- Remove unnecessary use return value store in dev_map_enqueue
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Yonghong Song says:
====================
Currently, suppose a userspace application has loaded a bpf program
and attached it to a tracepoint/kprobe/uprobe, and a bpf
introspection tool, e.g., bpftool, wants to show which bpf program
is attached to which tracepoint/kprobe/uprobe. Such attachment
information will be really useful to understand the overall bpf
deployment in the system.
There is a name field (16 bytes) for each program, which could
be used to encode the attachment point. There are some drawbacks
for this approaches. First, bpftool user (e.g., an admin) may not
really understand the association between the name and the
attachment point. Second, if one program is attached to multiple
places, encoding a proper name which can imply all these
attachments becomes difficult.
This patch introduces a new bpf subcommand BPF_TASK_FD_QUERY.
Given a pid and fd, this command will return bpf related information
to user space. Right now it only supports tracepoint/kprobe/uprobe
perf event fd's. For such a fd, BPF_TASK_FD_QUERY will return
. prog_id
. tracepoint name, or
. k[ret]probe funcname + offset or kernel addr, or
. u[ret]probe filename + offset
to the userspace.
The user can use "bpftool prog" to find more information about
bpf program itself with prog_id.
Patch #1 adds function perf_get_event() in kernel/events/core.c.
Patch #2 implements the bpf subcommand BPF_TASK_FD_QUERY.
Patch #3 syncs tools bpf.h header and also add bpf_task_fd_query()
in the libbpf library for samples/selftests/bpftool to use.
Patch #4 adds ksym_get_addr() utility function.
Patch #5 add a test in samples/bpf for querying k[ret]probes and
u[ret]probes.
Patch #6 add a test in tools/testing/selftests/bpf for querying
raw_tracepoint and tracepoint.
Patch #7 add a new subcommand "perf" to bpftool.
Changelogs:
v4 -> v5:
. return strlen(buf) instead of strlen(buf) + 1
in the attr.buf_len. As long as user provides
non-empty buffer, it will be filed with empty
string, truncated string, or full string
based on the buffer size and the length of
to-be-copied string.
v3 -> v4:
. made attr buf_len input/output. The length of
actual buffter is written to buf_len so user space knows
what is actually needed. If user provides a buffer
with length >= 1 but less than required, do partial
copy and return -ENOSPC.
. code simplification with put_user.
. changed query result attach_info to fd_type.
. add tests at selftests/bpf to test zero len, null buf and
insufficient buf.
v2 -> v3:
. made perf_get_event() return perf_event pointer const.
this was to ensure that event fields are not meddled.
. detect whether newly BPF_TASK_FD_QUERY is supported or
not in "bpftool perf" and warn users if it is not.
v1 -> v2:
. changed bpf subcommand name from BPF_PERF_EVENT_QUERY
to BPF_TASK_FD_QUERY.
. fixed various "bpftool perf" issues and added documentation
and auto-completion.
====================
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The new tests are added to query perf_event information
for raw_tracepoint and tracepoint attachment. For tracepoint,
both syscalls and non-syscalls tracepoints are queries as
they are treated slightly differently inside the kernel.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This is mostly to test kprobe/uprobe which needs kernel headers.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Given a kernel function name, ksym_get_addr() will return the kernel
address for this function, or 0 if it cannot find this function name
in /proc/kallsyms. This function will be used later when a kernel
address is used to initiate a kprobe perf event.
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
