Add missing initialization for ret variable. Its initialization
is based on the re_cnt variable, which is being set deep down
in the ftrace_function_filter_re function.
I'm not sure compilers would be smart enough to see this in near
future, so killing the warning this way.
Link: http://lkml.kernel.org/r/1340120894-9465-2-git-send-email-jolsa@redhat.com
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
The warkeup_rt self test used msleep() calls to wait for real time
tasks to wake up and run. On bare-metal hardware, this was enough as
the scheduler should let the RT task run way before the non-RT task
wakes up from the msleep(). If it did not, then that would mean the
scheduler was broken.
But when dealing with virtual machines, this is a different story.
If the RT task wakes up on a VCPU, it's up to the host to decide when
that task gets to schedule, which can be far behind the time that the
non-RT task wakes up. In this case, the test would fail incorrectly.
As we are not testing the scheduler, but instead the wake up tracing,
we can use completions to wait and not depend on scheduler timings
to see if events happen on time.
Link: http://lkml.kernel.org/r/1343663105.3847.7.camel@fedora
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Tested-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Introduce function trace based kprobes optimization.
With using ftrace optimization, kprobes on the mcount calling
address, use ftrace's mcount call instead of breakpoint.
Furthermore, this optimization works with preemptive kernel
not like as current jump-based optimization. Of cource,
this feature works only if the probe is on mcount call.
Only if kprobe.break_handler is set, that probe is not
optimized with ftrace (nor put on ftrace). The reason why this
limitation comes is that this break_handler may be used only
from jprobes which changes ip address (for fetching the function
arguments), but function tracer ignores modified ip address.
Changes in v2:
- Fix ftrace_ops registering right after setting its filter.
- Unregister ftrace_ops if there is no kprobe using.
- Remove notrace dependency from __kprobes macro.
Link: http://lkml.kernel.org/r/20120605102832.27845.63461.stgit@localhost.localdomain
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: "Frank Ch. Eigler" <fche@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
When CONFIG_DYNAMIC_FTRACE is not set, ftrace_location() is not defined.
If a user (like kprobes) references this function, it will break
the compile when CONFIG_DYNAMIC_FTRACE is not set.
Add ftrace_location() as a nop (return 0) when DYNAMIC_FTRACE
is not defined.
Link: http://lkml.kernel.org/r/20120612225426.961092717@goodmis.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Add selftests to test the save-regs functionality of ftrace.
If the arch supports saving regs, then it will make sure that regs is
at least not NULL in the callback.
If the arch does not support saving regs, it makes sure that the
registering of the ftrace_ops that requests saving regs fails.
It then tests the registering of the ftrace_ops succeeds if the
'IF_SUPPORTED' flag is set. Then it makes sure that the regs passed to
the function is NULL.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Add selftests to test the function tracing recursion protection actually
does work. It also tests if a ftrace_ops states it will perform its own
protection. Although, even if the ftrace_ops states it will protect itself,
the ftrace infrastructure may still provide protection if the arch does
not support all features or another ftrace_ops is registered.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
As more users of the function tracer utility are being added, they do
not always add the necessary recursion protection. To protect from
function recursion due to tracing, if the callback ftrace_ops does not
specifically specify that it protects against recursion (by setting
the FTRACE_OPS_FL_RECURSION_SAFE flag), the list operation will be
called by the mcount trampoline which adds recursion protection.
If the flag is set, then the function will be called directly with no
extra protection.
Note, the list operation is called if more than one function callback
is registered, or if the arch does not support all of the function
tracer features.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Add a way to have different functions calling different trampolines.
If a ftrace_ops wants regs saved on the return, then have only the
functions with ops registered to save regs. Functions registered by
other ops would not be affected, unless the functions overlap.
If one ftrace_ops registered functions A, B and C and another ops
registered fucntions to save regs on A, and D, then only functions
A and D would be saving regs. Function B and C would work as normal.
Although A is registered by both ops: normal and saves regs; this is fine
as saving the regs is needed to satisfy one of the ops that calls it
but the regs are ignored by the other ops function.
x86_64 implements the full regs saving, and i386 just passes a NULL
for regs to satisfy the ftrace_ops passing. Where an arch must supply
both regs and ftrace_ops parameters, even if regs is just NULL.
It is OK for an arch to pass NULL regs. All function trace users that
require regs passing must add the flag FTRACE_OPS_FL_SAVE_REGS when
registering the ftrace_ops. If the arch does not support saving regs
then the ftrace_ops will fail to register. The flag
FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED may be set that will prevent the
ftrace_ops from failing to register. In this case, the handler may
either check if regs is not NULL or check if ARCH_SUPPORTS_FTRACE_SAVE_REGS.
If the arch supports passing regs it will set this macro and pass regs
for ops that request them. All other archs will just pass NULL.
Link: Link: http://lkml.kernel.org/r/20120711195745.107705970@goodmis.org
Cc: Alexander van Heukelum <heukelum@fastmail.fm>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Return as the 4th paramater to the function tracer callback the pt_regs.
Later patches that implement regs passing for the architectures will require
having the ftrace_ops set the SAVE_REGS flag, which will tell the arch
to take the time to pass a full set of pt_regs to the ftrace_ops callback
function. If the arch does not support it then it should pass NULL.
If an arch can pass full regs, then it should define:
ARCH_SUPPORTS_FTRACE_SAVE_REGS to 1
Link: http://lkml.kernel.org/r/20120702201821.019966811@goodmis.org
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
As the function tracer starts to get more features, the support for
theses features will spread out throughout the different architectures
over time. These features boil down to what each arch does in the
mcount trampoline (the ftrace_caller).
Currently there's two features that are not the same throughout the
archs.
1) Support to stop function tracing before the callback
2) passing of the ftrace ops
Both of these require placing an indirect function to support the
features if the mcount trampoline does not.
On a side note, for all architectures, when more than one callback
is registered to the function tracer, an intermediate 'list' function
is called by the mcount trampoline to iterate through the callbacks
that are registered.
Instead of making a separate function for each of these features,
and requiring several indirect calls, just use the single 'list' function
as the intermediate, to handle all cases. If an arch does not support
the 'stop function tracing' or the passing of ftrace ops, just force
it to use the list function that will handle the features required.
This makes the code cleaner and simpler and removes a lot of
#ifdefs in the code.
Link: http://lkml.kernel.org/r/20120612225424.495625483@goodmis.org
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Currently the function trace callback receives only the ip and parent_ip
of the function that it traced. It would be more powerful to also return
the ops that registered the function as well. This allows the same function
to act differently depending on what ftrace_ops registered it.
Link: http://lkml.kernel.org/r/20120612225424.267254552@goodmis.org
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Pull networking fixes from David Miller:
1) IPVS oops'ers:
a) Should not reset skb->nf_bridge in forwarding hook (Lin Ming)
b) 3.4 commit can cause ip_vs_control_cleanup to be invoked after
the ipvs_core_ops are unregistered during rmmod (Julian ANastasov)
2) ixgbevf bringup failure can crash in TX descriptor cleanup
(Alexander Duyck)
3) AX25 switch missing break statement hoses ROSE sockets (Alan Cox)
4) CAIF accesses freed per-net memory (Sjur Brandeland)
5) Network cgroup code has out-or-bounds accesses (Eric DUmazet), and
accesses freed memory (Gao Feng)
6) Fix a crash in SCTP reported by Dave Jones caused by freeing an
association still on a list (Neil HOrman)
7) __netdev_alloc_skb() regresses on GFP_DMA using drivers because that
GFP flag is not being retained for the allocation (Eric Dumazet).
8) Missing NULL hceck in sch_sfb netlink message parsing (Alan Cox)
9) bnx2 crashes because TX index iteration is not bounded correctly
(Michael Chan)
10) IPoIB generates warnings in TCP queue collapsing (via
skb_try_coalesce) because it does not set skb->truesize correctly
(Eric Dumazet)
11) vlan_info objects leak for the implicit vlan with ID 0 (Amir
Hanania)
12) A fix for TX time stamp handling in gianfar does not transfer socket
ownership from one packet to another correctly, resulting in a
socket write space imbalance (Eric Dumazet)
13) Julia Lawall found several cases where we do a list iteration, and
then at the loop termination unconditionally assume we ended up with
real list object, rather than the list head itself (CNIC, RXRPC,
mISDN).
14) The bonding driver handles procfs moving incorrectly when a device
it manages is moved from one namespace to another (Eric Biederman)
15) Missing memory barriers in stmmac descriptor accesses result in
various crashes (Deepak Sikri)
16) Fix handling of broadcast packets in batman-adv (Simon Wunderlich)
17) Properly check the sanity of sendmsg() lengths in ieee802154's
dgram_sendmsg(). Dave Jones and others have hit and reported this
bug (Sasha Levin)
18) Some drivers (b44 and b43legacy) on 64-bit machines stopped working
because of how netdev_alloc_skb() was adjusted. Such drivers should
now use alloc_skb() for obtaining bounce buffers. (Eric Dumazet)
19) atl1c mis-managed it's link state in that it stops the queue by hand
on link down. The generic networking takes care of that and this
double stop locks the queue down. So simply removing the driver's
queue stop call fixes the problem (Cloud Ren)
20) Fix out-of-memory due to mis-accounting in net_em packet scheduler
(Eric Dumazet)
21) If DCB and SR-IOV are configured at the same time in IXGBE the chip
will hang because this is not supported (Alexander Duyck)
22) A commit to stop drivers using netdev->base_addr broke the CNIC
driver (Michael Chan)
23) Timeout regression in ipset caused by an attempt to fix an overflow
bug (Jozsef Kadlecsik).
24) mac80211 minstrel code allocates memory using incorrect size
(Thomas Huehn)
25) llcp_sock_getname() needs to check for a NULL device otherwise we
OOPS (Sasha Levin)
26) mwifiex leaks memory (Bing Zhao)
27) Propagate iwlwifi fix to iwlegacy, even when we're not associated
we need to monitor for stuck queues in the watchdog handler
(Stanislaw Geuszka)
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (44 commits)
ipvs: fix oops in ip_vs_dst_event on rmmod
ipvs: fix oops on NAT reply in br_nf context
ixgbevf: Fix panic when loading driver
ax25: Fix missing break
MAINTAINERS: reflect actual changes in IEEE 802.15.4 maintainership
caif: Fix access to freed pernet memory
net: cgroup: fix access the unallocated memory in netprio cgroup
ixgbevf: Prevent RX/TX statistics getting reset to zero
sctp: Fix list corruption resulting from freeing an association on a list
net: respect GFP_DMA in __netdev_alloc_skb()
e1000e: fix test for PHY being accessible on 82577/8/9 and I217
e1000e: Correct link check logic for 82571 serdes
sch_sfb: Fix missing NULL check
bnx2: Fix bug in bnx2_free_tx_skbs().
IPoIB: fix skb truesize underestimatiom
net: Fix memory leak - vlan_info struct
gianfar: fix potential sk_wmem_alloc imbalance
drivers/net/ethernet/broadcom/cnic.c: remove invalid reference to list iterator variable
net/rxrpc/ar-peer.c: remove invalid reference to list iterator variable
drivers/isdn/mISDN/stack.c: remove invalid reference to list iterator variable
...
Wang Tianhong
Jiri Olsa
Steven Rostedt
Masami Hiramatsu
Uros Bizjak
Ingo Molnar
Linus Torvalds