Commit Graph

3159 Commits

Author SHA1 Message Date
Daniel Borkmann 8e7a3920ac bpf, perf: split bpf_perf_event_output
Split the bpf_perf_event_output() helper as a preparation into
two parts. The new bpf_perf_event_output() will prepare the raw
record itself and test for unknown flags from BPF trace context,
where the __bpf_perf_event_output() does the core work. The
latter will be reused later on from bpf_event_output() directly.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-15 14:23:56 -07:00
Daniel Borkmann 7e3f977edd perf, events: add non-linear data support for raw records
This patch adds support for non-linear data on raw records. It
extends raw records to have one or multiple fragments that will
be written linearly into the ring slot, where each fragment can
optionally have a custom callback handler to walk and extract
complex, possibly non-linear data.

If a callback handler is provided for a fragment, then the new
__output_custom() will be used instead of __output_copy() for
the perf_output_sample() part. perf_prepare_sample() does all
the size calculation only once, so perf_output_sample() doesn't
need to redo the same work anymore, meaning real_size and padding
will be cached in the raw record. The raw record becomes 32 bytes
in size without holes; to not increase it further and to avoid
doing unnecessary recalculations in fast-path, we can reuse
next pointer of the last fragment, idea here is borrowed from
ZERO_OR_NULL_PTR(), which should keep the perf_output_sample()
path for PERF_SAMPLE_RAW minimal.

This facility is needed for BPF's event output helper as a first
user that will, in a follow-up, add an additional perf_raw_frag
to its perf_raw_record in order to be able to more efficiently
dump skb context after a linear head meta data related to it.
skbs can be non-linear and thus need a custom output function to
dump buffers. Currently, the skb data needs to be copied twice;
with the help of __output_custom() this work only needs to be
done once. Future users could be things like XDP/BPF programs
that work on different context though and would thus also have
a different callback function.

The few users of raw records are adapted to initialize their frag
data from the raw record itself, no change in behavior for them.
The code is based upon a PoC diff provided by Peter Zijlstra [1].

  [1] http://thread.gmane.org/gmane.linux.network/421294

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-15 14:23:56 -07:00
Alexei Starovoitov 606274c5ab bpf: introduce bpf_get_current_task() helper
over time there were multiple requests to access different data
structures and fields of task_struct current, so finally add
the helper to access 'current' as-is. Tracing bpf programs will do
the rest of walking the pointers via bpf_probe_read().
Note that current can be null and bpf program has to deal it with,
but even dumb passing null into bpf_probe_read() is still safe.

Suggested-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-09 00:00:16 -04:00
Daniel Borkmann 6816a7ffce bpf, trace: add BPF_F_CURRENT_CPU flag for bpf_perf_event_read
Follow-up commit to 1e33759c78 ("bpf, trace: add BPF_F_CURRENT_CPU
flag for bpf_perf_event_output") to add the same functionality into
bpf_perf_event_read() helper. The split of index into flags and index
component is also safe here, since such large maps are rejected during
map allocation time.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-30 05:54:40 -04:00
Daniel Borkmann d793133031 bpf, trace: fetch current cpu only once
We currently have two invocations, which is unnecessary. Fetch it only
once and use the smp_processor_id() variant, so we also get preemption
checks along with it when DEBUG_PREEMPT is set.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-30 05:54:40 -04:00
Daniel Borkmann 1ca1cc98bf bpf: minor cleanups on fd maps and helpers
Some minor cleanups: i) Remove the unlikely() from fd array map lookups
and let the CPU branch predictor do its job, scenarios where there is not
always a map entry are very well valid. ii) Move the attribute type check
in the bpf_perf_event_read() helper a bit earlier so it's consistent wrt
checks with bpf_perf_event_output() helper as well. iii) remove some
comments that are self-documenting in kprobe_prog_is_valid_access() and
therefore make it consistent to tp_prog_is_valid_access() as well.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-30 05:54:40 -04:00
David S. Miller ee58b57100 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Several cases of overlapping changes, except the packet scheduler
conflicts which deal with the addition of the free list parameter
to qdisc_enqueue().

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-30 05:03:36 -04:00
Linus Torvalds 32826ac41f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:
 "I've been traveling so this accumulates more than week or so of bug
  fixing.  It perhaps looks a little worse than it really is.

   1) Fix deadlock in ath10k driver, from Ben Greear.

   2) Increase scan timeout in iwlwifi, from Luca Coelho.

   3) Unbreak STP by properly reinjecting STP packets back into the
      stack.  Regression fix from Ido Schimmel.

   4) Mediatek driver fixes (missing malloc failure checks, leaking of
      scratch memory, wrong indexing when mapping TX buffers, etc.) from
      John Crispin.

   5) Fix endianness bug in icmpv6_err() handler, from Hannes Frederic
      Sowa.

   6) Fix hashing of flows in UDP in the ruseport case, from Xuemin Su.

   7) Fix netlink notifications in ovs for tunnels, delete link messages
      are never emitted because of how the device registry state is
      handled.  From Nicolas Dichtel.

   8) Conntrack module leaks kmemcache on unload, from Florian Westphal.

   9) Prevent endless jump loops in nft rules, from Liping Zhang and
      Pablo Neira Ayuso.

  10) Not early enough spinlock initialization in mlx4, from Eric
      Dumazet.

  11) Bind refcount leak in act_ipt, from Cong WANG.

  12) Missing RCU locking in HTB scheduler, from Florian Westphal.

  13) Several small MACSEC bug fixes from Sabrina Dubroca (missing RCU
      barrier, using heap for SG and IV, and erroneous use of async flag
      when allocating AEAD conext.)

  14) RCU handling fix in TIPC, from Ying Xue.

  15) Pass correct protocol down into ipv4_{update_pmtu,redirect}() in
      SIT driver, from Simon Horman.

  16) Socket timer deadlock fix in TIPC from Jon Paul Maloy.

  17) Fix potential deadlock in team enslave, from Ido Schimmel.

  18) Memory leak in KCM procfs handling, from Jiri Slaby.

  19) ESN generation fix in ipv4 ESP, from Herbert Xu.

  20) Fix GFP_KERNEL allocations with locks held in act_ife, from Cong
      WANG.

  21) Use after free in netem, from Eric Dumazet.

  22) Uninitialized last assert time in multicast router code, from Tom
      Goff.

  23) Skip raw sockets in sock_diag destruction broadcast, from Willem
      de Bruijn.

  24) Fix link status reporting in thunderx, from Sunil Goutham.

  25) Limit resegmentation of retransmit queue so that we do not
      retransmit too large GSO frames.  From Eric Dumazet.

  26) Delay bpf program release after grace period, from Daniel
      Borkmann"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (141 commits)
  openvswitch: fix conntrack netlink event delivery
  qed: Protect the doorbell BAR with the write barriers.
  neigh: Explicitly declare RCU-bh read side critical section in neigh_xmit()
  e1000e: keep VLAN interfaces functional after rxvlan off
  cfg80211: fix proto in ieee80211_data_to_8023 for frames without LLC header
  qlcnic: use the correct ring in qlcnic_83xx_process_rcv_ring_diag()
  bpf, perf: delay release of BPF prog after grace period
  net: bridge: fix vlan stats continue counter
  tcp: do not send too big packets at retransmit time
  ibmvnic: fix to use list_for_each_safe() when delete items
  net: thunderx: Fix TL4 configuration for secondary Qsets
  net: thunderx: Fix link status reporting
  net/mlx5e: Reorganize ethtool statistics
  net/mlx5e: Fix number of PFC counters reported to ethtool
  net/mlx5e: Prevent adding the same vxlan port
  net/mlx5e: Check for BlueFlame capability before allocating SQ uar
  net/mlx5e: Change enum to better reflect usage
  net/mlx5: Add ConnectX-5 PCIe 4.0 to list of supported devices
  net/mlx5: Update command strings
  net: marvell: Add separate config ANEG function for Marvell 88E1111
  ...
2016-06-29 11:50:42 -07:00
Steven Rostedt (Red Hat) 70c8217acd tracing: Handle NULL formats in hold_module_trace_bprintk_format()
If a task uses a non constant string for the format parameter in
trace_printk(), then the trace_printk_fmt variable is set to NULL. This
variable is then saved in the __trace_printk_fmt section.

The function hold_module_trace_bprintk_format() checks to see if duplicate
formats are used by modules, and reuses them if so (saves them to the list
if it is new). But this function calls lookup_format() that does a strcmp()
to the value (which is now NULL) and can cause a kernel oops.

This wasn't an issue till 3debb0a9dd ("tracing: Fix trace_printk() to print
when not using bprintk()") which added "__used" to the trace_printk_fmt
variable, and before that, the kernel simply optimized it out (no NULL value
was saved).

The fix is simply to handle the NULL pointer in lookup_format() and have the
caller ignore the value if it was NULL.

Link: http://lkml.kernel.org/r/1464769870-18344-1-git-send-email-zhengjun.xing@intel.com

Reported-by: xingzhen <zhengjun.xing@intel.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Fixes: 3debb0a9dd ("tracing: Fix trace_printk() to print when not using bprintk()")
Cc: stable@vger.kernel.org # v3.5+
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-06-20 09:46:12 -04:00
Daniel Borkmann 3b1efb196e bpf, maps: flush own entries on perf map release
The behavior of perf event arrays are quite different from all
others as they are tightly coupled to perf event fds, f.e. shown
recently by commit e03e7ee34f ("perf/bpf: Convert perf_event_array
to use struct file") to make refcounting on perf event more robust.
A remaining issue that the current code still has is that since
additions to the perf event array take a reference on the struct
file via perf_event_get() and are only released via fput() (that
cleans up the perf event eventually via perf_event_release_kernel())
when the element is either manually removed from the map from user
space or automatically when the last reference on the perf event
map is dropped. However, this leads us to dangling struct file's
when the map gets pinned after the application owning the perf
event descriptor exits, and since the struct file reference will
in such case only be manually dropped or via pinned file removal,
it leads to the perf event living longer than necessary, consuming
needlessly resources for that time.

Relations between perf event fds and bpf perf event map fds can be
rather complex. F.e. maps can act as demuxers among different perf
event fds that can possibly be owned by different threads and based
on the index selection from the program, events get dispatched to
one of the per-cpu fd endpoints. One perf event fd (or, rather a
per-cpu set of them) can also live in multiple perf event maps at
the same time, listening for events. Also, another requirement is
that perf event fds can get closed from application side after they
have been attached to the perf event map, so that on exit perf event
map will take care of dropping their references eventually. Likewise,
when such maps are pinned, the intended behavior is that a user
application does bpf_obj_get(), puts its fds in there and on exit
when fd is released, they are dropped from the map again, so the map
acts rather as connector endpoint. This also makes perf event maps
inherently different from program arrays as described in more detail
in commit c9da161c65 ("bpf: fix clearing on persistent program
array maps").

To tackle this, map entries are marked by the map struct file that
added the element to the map. And when the last reference to that map
struct file is released from user space, then the tracked entries
are purged from the map. This is okay, because new map struct files
instances resp. frontends to the anon inode are provided via
bpf_map_new_fd() that is called when we invoke bpf_obj_get_user()
for retrieving a pinned map, but also when an initial instance is
created via map_create(). The rest is resolved by the vfs layer
automatically for us by keeping reference count on the map's struct
file. Any concurrent updates on the map slot are fine as well, it
just means that perf_event_fd_array_release() needs to delete less
of its own entires.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-15 23:42:57 -07:00
Alexei Starovoitov ad572d1747 bpf, trace: check event type in bpf_perf_event_read
similar to bpf_perf_event_output() the bpf_perf_event_read() helper
needs to check the type of the perf_event before reading the counter.

Fixes: a43eec3042 ("bpf: introduce bpf_perf_event_output() helper")
Reported-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-15 23:37:54 -07:00
Alexei Starovoitov 19de99f70b bpf: fix matching of data/data_end in verifier
The ctx structure passed into bpf programs is different depending on bpf
program type. The verifier incorrectly marked ctx->data and ctx->data_end
access based on ctx offset only. That caused loads in tracing programs
int bpf_prog(struct pt_regs *ctx) { .. ctx->ax .. }
to be incorrectly marked as PTR_TO_PACKET which later caused verifier
to reject the program that was actually valid in tracing context.
Fix this by doing program type specific matching of ctx offsets.

Fixes: 969bf05eb3 ("bpf: direct packet access")
Reported-by: Sasha Goldshtein <goldshtn@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-15 23:37:54 -07:00
Daniel Borkmann 5b6c1b4d46 bpf, trace: use READ_ONCE for retrieving file ptr
In bpf_perf_event_read() and bpf_perf_event_output(), we must use
READ_ONCE() for fetching the struct file pointer, which could get
updated concurrently, so we must prevent the compiler from potential
refetching.

We already do this with tail calls for fetching the related bpf_prog,
but not so on stored perf events. Semantics for both are the same
with regards to updates.

Fixes: a43eec3042 ("bpf: introduce bpf_perf_event_output() helper")
Fixes: 35578d7984 ("bpf: Implement function bpf_perf_event_read() that get the selected hardware PMU conuter")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 14:48:03 -07:00
Linus Torvalds 7639dad93a Three more changes.
1) I forgot that I had another selftest to stress test the ftrace
    instance creation. It was actually suppose to go into the 4.6
    merge window, but I never committed it. I almost forgot about it
    again, but noticed it was missing from your tree.
 
 2) Soumya PN sent me a clean up patch to not disable interrupts when
    taking the tasklist_lock for read, as it's unnecessary because
    that lock is never taken for write in irq context.
 
 3) Newer gcc's can cause the jump in the function_graph code to the
    global ftrace_stub label to be a short jump instead of a long one.
    As that jump is dynamically converted to jump to the trace code to
    do function graph tracing, and that conversion expects a long jump
    it can corrupt the ftrace_stub itself (it's directly after that call).
    One way to prevent gcc from using a short jump is to declare the
    ftrace_stub as a weak function, which we do here to keep gcc from
    optimizing too much.
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Merge tag 'trace-v4.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull motr tracing updates from Steven Rostedt:
 "Three more changes.

   - I forgot that I had another selftest to stress test the ftrace
     instance creation.  It was actually suppose to go into the 4.6
     merge window, but I never committed it.  I almost forgot about it
     again, but noticed it was missing from your tree.

   - Soumya PN sent me a clean up patch to not disable interrupts when
     taking the tasklist_lock for read, as it's unnecessary because that
     lock is never taken for write in irq context.

   - Newer gcc's can cause the jump in the function_graph code to the
     global ftrace_stub label to be a short jump instead of a long one.
     As that jump is dynamically converted to jump to the trace code to
     do function graph tracing, and that conversion expects a long jump
     it can corrupt the ftrace_stub itself (it's directly after that
     call).  One way to prevent gcc from using a short jump is to
     declare the ftrace_stub as a weak function, which we do here to
     keep gcc from optimizing too much"

* tag 'trace-v4.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace/x86: Set ftrace_stub to weak to prevent gcc from using short jumps to it
  ftrace: Don't disable irqs when taking the tasklist_lock read_lock
  ftracetest: Add instance created, delete, read and enable event test
2016-05-22 19:40:39 -07:00
Soumya PN 6112a300c9 ftrace: Don't disable irqs when taking the tasklist_lock read_lock
In ftrace.c inside the function alloc_retstack_tasklist() (which will be
invoked when function_graph tracing is on) the tasklist_lock is being
held as reader while iterating through a list of threads. Here the lock
is being held as reader with irqs disabled. The tasklist_lock is never
write_locked in interrupt context so it is safe to not disable interrupts
for the duration of read_lock in this block which, can be significant,
given the block of code iterates through all threads. Hence changing the
code to call read_lock() and read_unlock() instead of read_lock_irqsave()
and read_unlock_irqrestore().

A similar change was made in commits: 8063e41d2f ("tracing: Change
syscall_*regfunc() to check PF_KTHREAD and use for_each_process_thread()")'
and 3472eaa1f1 ("sched: normalize_rt_tasks(): Don't use _irqsave for
tasklist_lock, use task_rq_lock()")'

Link: http://lkml.kernel.org/r/1463500874-77480-1-git-send-email-soumya.p.n@hpe.com

Signed-off-by: Soumya PN <soumya.p.n@hpe.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-05-20 13:19:37 -04:00
Linus Torvalds c04a588029 powerpc updates for 4.7
Highlights:
  - Support for Power ISA 3.0 (Power9) Radix Tree MMU from Aneesh Kumar K.V
  - Live patching support for ppc64le (also merged via livepatching.git)
 
 Various cleanups & minor fixes from:
  - Aaro Koskinen, Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V,
    Chris Smart, Daniel Axtens, Frederic Barrat, Gavin Shan, Ian Munsie, Lennart
    Sorensen, Madhavan Srinivasan, Mahesh Salgaonkar, Markus Elfring, Michael
    Ellerman, Oliver O'Halloran, Paul Gortmaker, Paul Mackerras, Rashmica Gupta,
    Russell Currey, Suraj Jitindar Singh, Thiago Jung Bauermann, Valentin
    Rothberg, Vipin K Parashar.
 
 General:
  - Update LMB associativity index during DLPAR add/remove from Nathan Fontenot
  - Fix branching to OOL handlers in relocatable kernel from Hari Bathini
  - Add support for userspace Power9 copy/paste from Chris Smart
  - Always use STRICT_MM_TYPECHECKS from Michael Ellerman
  - Add mask of possible MMU features from Michael Ellerman
 
 PCI:
  - Enable pass through of NVLink to guests from Alexey Kardashevskiy
  - Cleanups in preparation for powernv PCI hotplug from Gavin Shan
  - Don't report error in eeh_pe_reset_and_recover() from Gavin Shan
  - Restore initial state in eeh_pe_reset_and_recover() from Gavin Shan
  - Revert "powerpc/eeh: Fix crash in eeh_add_device_early() on Cell" from Guilherme G. Piccoli
  - Remove the dependency on EEH struct in DDW mechanism from Guilherme G. Piccoli
 
 selftests:
  - Test cp_abort during context switch from Chris Smart
  - Add several tests for transactional memory support from Rashmica Gupta
 
 perf:
  - Add support for sampling interrupt register state from Anju T
  - Add support for unwinding perf-stackdump from Chandan Kumar
 
 cxl:
  - Configure the PSL for two CAPI ports on POWER8NVL from Philippe Bergheaud
  - Allow initialization on timebase sync failures from Frederic Barrat
  - Increase timeout for detection of AFU mmio hang from Frederic Barrat
  - Handle num_of_processes larger than can fit in the SPA from Ian Munsie
  - Ensure PSL interrupt is configured for contexts with no AFU IRQs from Ian Munsie
  - Add kernel API to allow a context to operate with relocate disabled from Ian Munsie
  - Check periodically the coherent platform function's state from Christophe Lombard
 
 Freescale:
  - Updates from Scott: "Contains 86xx fixes, minor device tree fixes, an erratum
    workaround, and a kconfig dependency fix."
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Merge tag 'powerpc-4.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Highlights:
   - Support for Power ISA 3.0 (Power9) Radix Tree MMU from Aneesh Kumar K.V
   - Live patching support for ppc64le (also merged via livepatching.git)

  Various cleanups & minor fixes from:
   - Aaro Koskinen, Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V,
     Chris Smart, Daniel Axtens, Frederic Barrat, Gavin Shan, Ian Munsie,
     Lennart Sorensen, Madhavan Srinivasan, Mahesh Salgaonkar, Markus Elfring,
     Michael Ellerman, Oliver O'Halloran, Paul Gortmaker, Paul Mackerras,
     Rashmica Gupta, Russell Currey, Suraj Jitindar Singh, Thiago Jung
     Bauermann, Valentin Rothberg, Vipin K Parashar.

  General:
   - Update LMB associativity index during DLPAR add/remove from Nathan
     Fontenot
   - Fix branching to OOL handlers in relocatable kernel from Hari Bathini
   - Add support for userspace Power9 copy/paste from Chris Smart
   - Always use STRICT_MM_TYPECHECKS from Michael Ellerman
   - Add mask of possible MMU features from Michael Ellerman

  PCI:
   - Enable pass through of NVLink to guests from Alexey Kardashevskiy
   - Cleanups in preparation for powernv PCI hotplug from Gavin Shan
   - Don't report error in eeh_pe_reset_and_recover() from Gavin Shan
   - Restore initial state in eeh_pe_reset_and_recover() from Gavin Shan
   - Revert "powerpc/eeh: Fix crash in eeh_add_device_early() on Cell"
     from Guilherme G Piccoli
   - Remove the dependency on EEH struct in DDW mechanism from Guilherme
     G Piccoli

  selftests:
   - Test cp_abort during context switch from Chris Smart
   - Add several tests for transactional memory support from Rashmica
     Gupta

  perf:
   - Add support for sampling interrupt register state from Anju T
   - Add support for unwinding perf-stackdump from Chandan Kumar

  cxl:
   - Configure the PSL for two CAPI ports on POWER8NVL from Philippe
     Bergheaud
   - Allow initialization on timebase sync failures from Frederic Barrat
   - Increase timeout for detection of AFU mmio hang from Frederic
     Barrat
   - Handle num_of_processes larger than can fit in the SPA from Ian
     Munsie
   - Ensure PSL interrupt is configured for contexts with no AFU IRQs
     from Ian Munsie
   - Add kernel API to allow a context to operate with relocate disabled
     from Ian Munsie
   - Check periodically the coherent platform function's state from
     Christophe Lombard

  Freescale:
   - Updates from Scott: "Contains 86xx fixes, minor device tree fixes,
     an erratum workaround, and a kconfig dependency fix."

* tag 'powerpc-4.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (192 commits)
  powerpc/86xx: Fix PCI interrupt map definition
  powerpc/86xx: Move pci1 definition to the include file
  powerpc/fsl: Fix build of the dtb embedded kernel images
  powerpc/fsl: Fix rcpm compatible string
  powerpc/fsl: Remove FSL_SOC dependency from FSL_LBC
  powerpc/fsl-pci: Add a workaround for PCI 5 errata
  powerpc/fsl: Fix SPI compatible on t208xrdb and t1040rdb
  powerpc/powernv/npu: Add PE to PHB's list
  powerpc/powernv: Fix insufficient memory allocation
  powerpc/iommu: Remove the dependency on EEH struct in DDW mechanism
  Revert "powerpc/eeh: Fix crash in eeh_add_device_early() on Cell"
  powerpc/eeh: Drop unnecessary label in eeh_pe_change_owner()
  powerpc/eeh: Ignore handlers in eeh_pe_reset_and_recover()
  powerpc/eeh: Restore initial state in eeh_pe_reset_and_recover()
  powerpc/eeh: Don't report error in eeh_pe_reset_and_recover()
  Revert "powerpc/powernv: Exclude root bus in pnv_pci_reset_secondary_bus()"
  powerpc/powernv/npu: Enable NVLink pass through
  powerpc/powernv/npu: Rework TCE Kill handling
  powerpc/powernv/npu: Add set/unset window helpers
  powerpc/powernv/ioda2: Export debug helper pe_level_printk()
  ...
2016-05-20 10:12:41 -07:00
Linus Torvalds 2600a46ee0 This includes two new updates for the ftrace infrastructure.
1) With the changing of the code for filtering events by pid, from
   a list of pids to a bitmask, we can now easily implement following
   forks. With a new tracing option "event-fork" which, when set, will
   have tasks with pids in set_event_pid, when they fork, to have their
   child pids added to set_event_pid and the child will be traced as well.
 
   Note, if "event-fork" is set and a task with its pid in set_event_pid
   exits, its pid will be removed from set_event_pid
 
 2) The addition of Tom Zanussi's hist triggers. This includes a very
    thorough documentatino on how to use the hist triggers with events.
    This introduces a quick and easy way to get histogram data from
    events and their fields.
 
 Some other cleanups and updates were added as well. Like Masami Hiramatsu
 added test cases for the event trigger and hist triggers. Also I added
 a speed up of filtering by using a temp buffer when filters are set.
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Merge tag 'trace-v4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "This includes two new updates for the ftrace infrastructure.

   - With the changing of the code for filtering events by pid, from a
     list of pids to a bitmask, we can now easily implement following
     forks.  With a new tracing option "event-fork" which, when set,
     will have tasks with pids in set_event_pid, when they fork, to have
     their child pids added to set_event_pid and the child will be
     traced as well.

     Note, if "event-fork" is set and a task with its pid in
     set_event_pid exits, its pid will be removed from set_event_pid

   - The addition of Tom Zanussi's hist triggers.  This includes a very
     thorough documentatino on how to use the hist triggers with events.
     This introduces a quick and easy way to get histogram data from
     events and their fields.

  Some other cleanups and updates were added as well.  Like Masami
  Hiramatsu added test cases for the event trigger and hist triggers.
  Also I added a speed up of filtering by using a temp buffer when
  filters are set"

* tag 'trace-v4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (45 commits)
  tracing: Use temp buffer when filtering events
  tracing: Remove TRACE_EVENT_FL_USE_CALL_FILTER logic
  tracing: Remove unused function trace_current_buffer_lock_reserve()
  tracing: Remove one use of trace_current_buffer_lock_reserve()
  tracing: Have trace_buffer_unlock_commit() call the _regs version with NULL
  tracing: Remove unused function trace_current_buffer_discard_commit()
  tracing: Move trace_buffer_unlock_commit{_regs}() to local header
  tracing: Fold filter_check_discard() into its only user
  tracing: Make filter_check_discard() local
  tracing: Move event_trigger_unlock_commit{_regs}() to local header
  tracing: Don't use the address of the buffer array name in copy_from_user
  tracing: Handle tracing_map_alloc_elts() error path correctly
  tracing: Add check for NULL event field when creating hist field
  tracing: checking for NULL instead of IS_ERR()
  tracing: Do not inherit event-fork option for instances
  tracing: Fix unsigned comparison to zero in hist trigger code
  kselftests/ftrace: Add a test for log2 modifier of hist trigger
  tracing: Add hist trigger 'log2' modifier
  kselftests/ftrace: Add hist trigger testcases
  kselftests/ftrace : Add event trigger testcases
  ...
2016-05-18 18:55:19 -07:00
Linus Torvalds 0b86c75db6 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching
Pull livepatching updates from Jiri Kosina:

 - remove of our own implementation of architecture-specific relocation
   code and leveraging existing code in the module loader to perform
   arch-dependent work, from Jessica Yu.

   The relevant patches have been acked by Rusty (for module.c) and
   Heiko (for s390).

 - live patching support for ppc64le, which is a joint work of Michael
   Ellerman and Torsten Duwe.  This is coming from topic branch that is
   share between livepatching.git and ppc tree.

 - addition of livepatching documentation from Petr Mladek

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
  livepatch: make object/func-walking helpers more robust
  livepatch: Add some basic livepatch documentation
  powerpc/livepatch: Add live patching support on ppc64le
  powerpc/livepatch: Add livepatch stack to struct thread_info
  powerpc/livepatch: Add livepatch header
  livepatch: Allow architectures to specify an alternate ftrace location
  ftrace: Make ftrace_location_range() global
  livepatch: robustify klp_register_patch() API error checking
  Documentation: livepatch: outline Elf format and requirements for patch modules
  livepatch: reuse module loader code to write relocations
  module: s390: keep mod_arch_specific for livepatch modules
  module: preserve Elf information for livepatch modules
  Elf: add livepatch-specific Elf constants
2016-05-17 17:11:27 -07:00
Linus Torvalds a7fd20d1c4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Highlights:

   1) Support SPI based w5100 devices, from Akinobu Mita.

   2) Partial Segmentation Offload, from Alexander Duyck.

   3) Add GMAC4 support to stmmac driver, from Alexandre TORGUE.

   4) Allow cls_flower stats offload, from Amir Vadai.

   5) Implement bpf blinding, from Daniel Borkmann.

   6) Optimize _ASYNC_ bit twiddling on sockets, unless the socket is
      actually using FASYNC these atomics are superfluous.  From Eric
      Dumazet.

   7) Run TCP more preemptibly, also from Eric Dumazet.

   8) Support LED blinking, EEPROM dumps, and rxvlan offloading in mlx5e
      driver, from Gal Pressman.

   9) Allow creating ppp devices via rtnetlink, from Guillaume Nault.

  10) Improve BPF usage documentation, from Jesper Dangaard Brouer.

  11) Support tunneling offloads in qed, from Manish Chopra.

  12) aRFS offloading in mlx5e, from Maor Gottlieb.

  13) Add RFS and RPS support to SCTP protocol, from Marcelo Ricardo
      Leitner.

  14) Add MSG_EOR support to TCP, this allows controlling packet
      coalescing on application record boundaries for more accurate
      socket timestamp sampling.  From Martin KaFai Lau.

  15) Fix alignment of 64-bit netlink attributes across the board, from
      Nicolas Dichtel.

  16) Per-vlan stats in bridging, from Nikolay Aleksandrov.

  17) Several conversions of drivers to ethtool ksettings, from Philippe
      Reynes.

  18) Checksum neutral ILA in ipv6, from Tom Herbert.

  19) Factorize all of the various marvell dsa drivers into one, from
      Vivien Didelot

  20) Add VF support to qed driver, from Yuval Mintz"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1649 commits)
  Revert "phy dp83867: Fix compilation with CONFIG_OF_MDIO=m"
  Revert "phy dp83867: Make rgmii parameters optional"
  r8169: default to 64-bit DMA on recent PCIe chips
  phy dp83867: Make rgmii parameters optional
  phy dp83867: Fix compilation with CONFIG_OF_MDIO=m
  bpf: arm64: remove callee-save registers use for tmp registers
  asix: Fix offset calculation in asix_rx_fixup() causing slow transmissions
  switchdev: pass pointer to fib_info instead of copy
  net_sched: close another race condition in tcf_mirred_release()
  tipc: fix nametable publication field in nl compat
  drivers: net: Don't print unpopulated net_device name
  qed: add support for dcbx.
  ravb: Add missing free_irq() calls to ravb_close()
  qed: Remove a stray tab
  net: ethernet: fec-mpc52xx: use phy_ethtool_{get|set}_link_ksettings
  net: ethernet: fec-mpc52xx: use phydev from struct net_device
  bpf, doc: fix typo on bpf_asm descriptions
  stmmac: hardware TX COE doesn't work when force_thresh_dma_mode is set
  net: ethernet: fs-enet: use phy_ethtool_{get|set}_link_ksettings
  net: ethernet: fs-enet: use phydev from struct net_device
  ...
2016-05-17 16:26:30 -07:00
Linus Torvalds a4d1dbed0e Merge branch 'for-4.7/core' of git://git.kernel.dk/linux-block
Pull core block layer updates from Jens Axboe:
 "This is the core block IO changes for this merge window.  Nothing
  earth shattering in here, it's mostly just fixes.  In detail:

   - Fix for a long standing issue where wrong ordering in blk-mq caused
     order_to_size() to spew a warning.  From Bart.

   - Async discard support from Christoph.  Basically just splitting our
     sync interface into a submit + wait part.

   - Add a cleaner interface for flagging whether a device has a write
     back cache or not.  We've previously overloaded blk_queue_flush()
     with this, but let's make it more explicit.  Drivers cleaned up and
     updated in the drivers pull request.  From me.

   - Fix for a double check for whether IO accounting is enabled or not.
     From Michael Callahan.

   - Fix for the async discard from Mike Snitzer, reinstating the early
     EOPNOTSUPP return if the device doesn't support discards.

   - Also from Mike, export bio_inc_remaining() so dm can drop it's
     private copy of it.

   - From Ming Lin, add support for passing in an offset for request
     payloads.

   - Tag function export from Sagi, which will be used in NVMe in the
     drivers pull.

   - Two blktrace related fixes from Shaohua.

   - Propagate NOMERGE flag when making a request from a bio, also from
     Shaohua.

   - An optimization to not parse cgroup paths in blk-throttle, if we
     don't need to.  From Shaohua"

* 'for-4.7/core' of git://git.kernel.dk/linux-block:
  blk-mq: fix undefined behaviour in order_to_size()
  blk-throttle: don't parse cgroup path if trace isn't enabled
  blktrace: add missed mask name
  blktrace: delete garbage for message trace
  block: make bio_inc_remaining() interface accessible again
  block: reinstate early return of -EOPNOTSUPP from blkdev_issue_discard
  block: Minor blk_account_io_start usage cleanup
  block: add __blkdev_issue_discard
  block: remove struct bio_batch
  block: copy NOMERGE flag from bio to request
  block: add ability to flag write back caching on a device
  blk-mq: Export tagset iter function
  block: add offset in blk_add_request_payload()
  writeback: Fix performance regression in wb_over_bg_thresh()
2016-05-17 15:29:49 -07:00
Linus Torvalds 2fe2edf85f Hao Qin reported an integer overflow possibility with signed and
unsigned numbers in the ring-buffer code.
 
   https://bugzilla.kernel.org/show_bug.cgi?id=118001
 
 At first I did not think this was too much of an issue, because the
 overflow would be caught later when either too much data was allocated
 or it would trigger RB_WARN_ON() which shuts down the ring buffer.
 
 But looking closer into it, I found that the right settings could bypass
 the checks and crash the kernel. Luckily, this is only accessible
 by root.
 
 The first fix is to convert all the variables into long, such that
 we don't get into issues between 32 bit variables being assigned 64 bit
 ones. This fixes the RB_WARN_ON() triggering.
 
 The next fix is to get rid of a duplicate DIV_ROUND_UP() that when called
 twice with the right value, can cause a kernel crash.
 
 The first DIV_ROUND_UP() is to normalize the input and it is checked
 against the minimum allowable value. But then DIV_ROUND_UP() is called
 again, which can overflow due to the (a + b - 1)/b, logic. The first
 called upped the value, the second can overflow (with the +b part).
 
 The second call to DIV_ROUND_UP() came in via a second change a while ago
 and the code is cleaned up to remove it.
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Merge tag 'trace-fixes-v4.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing ring-buffer fixes from Steven Rostedt:
 "Hao Qin reported an integer overflow possibility with signed and
  unsigned numbers in the ring-buffer code.

    https://bugzilla.kernel.org/show_bug.cgi?id=118001

  At first I did not think this was too much of an issue, because the
  overflow would be caught later when either too much data was allocated
  or it would trigger RB_WARN_ON() which shuts down the ring buffer.

  But looking closer into it, I found that the right settings could
  bypass the checks and crash the kernel.  Luckily, this is only
  accessible by root.

  The first fix is to convert all the variables into long, such that we
  don't get into issues between 32 bit variables being assigned 64 bit
  ones.  This fixes the RB_WARN_ON() triggering.

  The next fix is to get rid of a duplicate DIV_ROUND_UP() that when
  called twice with the right value, can cause a kernel crash.

  The first DIV_ROUND_UP() is to normalize the input and it is checked
  against the minimum allowable value.  But then DIV_ROUND_UP() is
  called again, which can overflow due to the (a + b - 1)/b, logic.  The
  first called upped the value, the second can overflow (with the +b
  part).

  The second call to DIV_ROUND_UP() came in via a second change a while
  ago and the code is cleaned up to remove it"

* tag 'trace-fixes-v4.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ring-buffer: Prevent overflow of size in ring_buffer_resize()
  ring-buffer: Use long for nr_pages to avoid overflow failures
2016-05-17 09:42:58 -07:00
Linus Torvalds d57d394319 Power management material for v4.7-rc1
- New cpufreq "schedutil" governor (making decisions based on CPU
    utilization information provided by the scheduler and capable of
    switching CPU frequencies right away if the underlying driver
    supports that) and support for fast frequency switching in the
    acpi-cpufreq driver (Rafael Wysocki).
 
  - Consolidation of CPU frequency management on ARM platforms allowing
    them to get rid of some platform-specific boilerplate code if they
    are going to use the cpufreq-dt driver (Viresh Kumar, Finley Xiao,
    Marc Gonzalez).
 
  - Support for ACPI _PPC and CPU frequency limits in the intel_pstate
    driver (Srinivas Pandruvada).
 
  - Fixes and cleanups in the cpufreq core and generic governor code
    (Rafael Wysocki, Sai Gurrappadi).
 
  - intel_pstate driver optimizations and cleanups (Rafael Wysocki,
    Philippe Longepe, Chen Yu, Joe Perches).
 
  - cpufreq powernv driver fixes and cleanups (Akshay Adiga, Shilpasri
    Bhat).
 
  - cpufreq qoriq driver fixes and cleanups (Jia Hongtao).
 
  - ACPI cpufreq driver cleanups (Viresh Kumar).
 
  - Assorted cpufreq driver updates (Ashwin Chaugule, Geliang Tang,
    Javier Martinez Canillas, Paul Gortmaker, Sudeep Holla).
 
  - Assorted cpufreq fixes and cleanups (Joe Perches, Arnd Bergmann).
 
  - Fixes and cleanups in the OPP (Operating Performance Points)
    framework, mostly related to OPP sharing, and reorganization of
    OF-dependent code in it (Viresh Kumar, Arnd Bergmann, Sudeep Holla).
 
  - New "passive" governor for devfreq (for SoC subsystems that will
    rely on someone else for the management of their power resources)
    and consolidation of devfreq support for Exynos platforms, coding
    style and typo fixes for devfreq (Chanwoo Choi, MyungJoo Ham).
 
  - PM core fixes and cleanups, mostly to make it work better with the
    generic power domains (genpd) framework, and updates for that
    framework (Ulf Hansson, Thierry Reding, Colin Ian King).
 
  - Intel Broxton support for the intel_idle driver (Len Brown).
 
  - cpuidle core optimization and fix (Daniel Lezcano, Dave Gerlach).
 
  - ARM cpuidle cleanups (Jisheng Zhang).
 
  - Intel Kabylake support for the RAPL power capping driver (Jacob Pan).
 
  - AVS (Adaptive Voltage Switching) rockchip-io driver update (Heiko
    Stuebner).
 
  - Updates for the cpupower tool (Arjun Sreedharan, Colin Ian King,
    Mattia Dongili, Thomas Renninger).
 
 /
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Merge tag 'pm-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management updates from Rafael Wysocki:
 "The majority of changes go into the cpufreq subsystem this time.

  To me, quite obviously, the biggest ticket item is the new "schedutil"
  governor.  Interestingly enough, it's the first new cpufreq governor
  since the beginning of the git era (except for some out-of-the-tree
  ones).

  There are two main differences between it and the existing governors.
  First, it uses the information provided by the scheduler directly for
  making its decisions, so it doesn't have to track anything by itself.
  Second, it can invoke drivers (supporting that feature) to adjust CPU
  performance right away without having to spawn work items to be
  executed in process context or similar.  Currently, the acpi-cpufreq
  driver is the only one supporting that mode of operation, but then it
  is used on a large number of systems.

  The "schedutil" governor as included here is very simple and mostly
  regarded as a foundation for future work on the integration of the
  scheduler with CPU power management (in fact, there is work in
  progress on top of it already).  Nevertheless it works and the
  preliminary results obtained with it are encouraging.

  There also is some consolidation of CPU frequency management for ARM
  platforms that can add their machine IDs the the new stub dt-platdev
  driver now and that will take care of creating the requisite platform
  device for cpufreq-dt, so it is not necessary to do that in platform
  code any more.  Several ARM platforms are switched over to using this
  generic mechanism.

  In addition to that, the intel_pstate driver is now going to respect
  CPU frequency limits set by the platform firmware (or a BMC) and
  provided via the ACPI _PPC object.

  The devfreq subsystem is getting a new "passive" governor for SoCs
  subsystems that will depend on somebody else to manage their voltage
  rails and its support for Samsung Exynos SoCs is consolidated.

  The rest is support for new hardware (Intel Broxton support in
  intel_idle for one example), bug fixes, optimizations and cleanups in
  a number of places.

  Specifics:

   - New cpufreq "schedutil" governor (making decisions based on CPU
     utilization information provided by the scheduler and capable of
     switching CPU frequencies right away if the underlying driver
     supports that) and support for fast frequency switching in the
     acpi-cpufreq driver (Rafael Wysocki)

   - Consolidation of CPU frequency management on ARM platforms allowing
     them to get rid of some platform-specific boilerplate code if they
     are going to use the cpufreq-dt driver (Viresh Kumar, Finley Xiao,
     Marc Gonzalez)

   - Support for ACPI _PPC and CPU frequency limits in the intel_pstate
     driver (Srinivas Pandruvada)

   - Fixes and cleanups in the cpufreq core and generic governor code
     (Rafael Wysocki, Sai Gurrappadi)

   - intel_pstate driver optimizations and cleanups (Rafael Wysocki,
     Philippe Longepe, Chen Yu, Joe Perches)

   - cpufreq powernv driver fixes and cleanups (Akshay Adiga, Shilpasri
     Bhat)

   - cpufreq qoriq driver fixes and cleanups (Jia Hongtao)

   - ACPI cpufreq driver cleanups (Viresh Kumar)

   - Assorted cpufreq driver updates (Ashwin Chaugule, Geliang Tang,
     Javier Martinez Canillas, Paul Gortmaker, Sudeep Holla)

   - Assorted cpufreq fixes and cleanups (Joe Perches, Arnd Bergmann)

   - Fixes and cleanups in the OPP (Operating Performance Points)
     framework, mostly related to OPP sharing, and reorganization of
     OF-dependent code in it (Viresh Kumar, Arnd Bergmann, Sudeep Holla)

   - New "passive" governor for devfreq (for SoC subsystems that will
     rely on someone else for the management of their power resources)
     and consolidation of devfreq support for Exynos platforms, coding
     style and typo fixes for devfreq (Chanwoo Choi, MyungJoo Ham)

   - PM core fixes and cleanups, mostly to make it work better with the
     generic power domains (genpd) framework, and updates for that
     framework (Ulf Hansson, Thierry Reding, Colin Ian King)

   - Intel Broxton support for the intel_idle driver (Len Brown)

   - cpuidle core optimization and fix (Daniel Lezcano, Dave Gerlach)

   - ARM cpuidle cleanups (Jisheng Zhang)

   - Intel Kabylake support for the RAPL power capping driver (Jacob
     Pan)

   - AVS (Adaptive Voltage Switching) rockchip-io driver update (Heiko
     Stuebner)

   - Updates for the cpupower tool (Arjun Sreedharan, Colin Ian King,
     Mattia Dongili, Thomas Renninger)"

* tag 'pm-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (112 commits)
  intel_pstate: Clean up get_target_pstate_use_performance()
  intel_pstate: Use sample.core_avg_perf in get_avg_pstate()
  intel_pstate: Clarify average performance computation
  intel_pstate: Avoid unnecessary synchronize_sched() during initialization
  cpufreq: schedutil: Make default depend on CONFIG_SMP
  cpufreq: powernv: del_timer_sync when global and local pstate are equal
  cpufreq: powernv: Move smp_call_function_any() out of irq safe block
  intel_pstate: Clean up intel_pstate_get()
  cpufreq: schedutil: Make it depend on CONFIG_SMP
  cpufreq: governor: Fix handling of special cases in dbs_update()
  PM / OPP: Move CONFIG_OF dependent code in a separate file
  cpufreq: intel_pstate: Ignore _PPC processing under HWP
  cpufreq: arm_big_little: use generic OPP functions for {init, free}_opp_table
  PM / OPP: add non-OF versions of dev_pm_opp_{cpumask_, }remove_table
  cpufreq: tango: Use generic platdev driver
  PM / OPP: pass cpumask by reference
  cpufreq: Fix GOV_LIMITS handling for the userspace governor
  cpupower: fix potential memory leak
  PM / devfreq: style/typo fixes
  PM / devfreq: exynos: Add the detailed correlation for Exynos5422 bus
  ..
2016-05-16 19:17:22 -07:00
Rafael J. Wysocki c47b3bd0d3 Merge branch 'pm-cpufreq'
* pm-cpufreq: (63 commits)
  intel_pstate: Clean up get_target_pstate_use_performance()
  intel_pstate: Use sample.core_avg_perf in get_avg_pstate()
  intel_pstate: Clarify average performance computation
  intel_pstate: Avoid unnecessary synchronize_sched() during initialization
  cpufreq: schedutil: Make default depend on CONFIG_SMP
  cpufreq: powernv: del_timer_sync when global and local pstate are equal
  cpufreq: powernv: Move smp_call_function_any() out of irq safe block
  intel_pstate: Clean up intel_pstate_get()
  cpufreq: schedutil: Make it depend on CONFIG_SMP
  cpufreq: governor: Fix handling of special cases in dbs_update()
  cpufreq: intel_pstate: Ignore _PPC processing under HWP
  cpufreq: arm_big_little: use generic OPP functions for {init, free}_opp_table
  cpufreq: tango: Use generic platdev driver
  cpufreq: Fix GOV_LIMITS handling for the userspace governor
  cpufreq: mvebu: Move cpufreq code into drivers/cpufreq/
  cpufreq: dt: Kill platform-data
  mvebu: Use dev_pm_opp_set_sharing_cpus() to mark OPP tables as shared
  cpufreq: dt: Identify cpu-sharing for platforms without operating-points-v2
  cpufreq: governor: Change confusing struct field and variable names
  cpufreq: intel_pstate: Enable PPC enforcement for servers
  ...
2016-05-16 14:30:43 +02:00
Steven Rostedt (Red Hat) 59643d1535 ring-buffer: Prevent overflow of size in ring_buffer_resize()
If the size passed to ring_buffer_resize() is greater than MAX_LONG - BUF_PAGE_SIZE
then the DIV_ROUND_UP() will return zero.

Here's the details:

  # echo 18014398509481980 > /sys/kernel/debug/tracing/buffer_size_kb

tracing_entries_write() processes this and converts kb to bytes.

 18014398509481980 << 10 = 18446744073709547520

and this is passed to ring_buffer_resize() as unsigned long size.

 size = DIV_ROUND_UP(size, BUF_PAGE_SIZE);

Where DIV_ROUND_UP(a, b) is (a + b - 1)/b

BUF_PAGE_SIZE is 4080 and here

 18446744073709547520 + 4080 - 1 = 18446744073709551599

where 18446744073709551599 is still smaller than 2^64

 2^64 - 18446744073709551599 = 17

But now 18446744073709551599 / 4080 = 4521260802379792

and size = size * 4080 = 18446744073709551360

This is checked to make sure its still greater than 2 * 4080,
which it is.

Then we convert to the number of buffer pages needed.

 nr_page = DIV_ROUND_UP(size, BUF_PAGE_SIZE)

but this time size is 18446744073709551360 and

 2^64 - (18446744073709551360 + 4080 - 1) = -3823

Thus it overflows and the resulting number is less than 4080, which makes

  3823 / 4080 = 0

an nr_pages is set to this. As we already checked against the minimum that
nr_pages may be, this causes the logic to fail as well, and we crash the
kernel.

There's no reason to have the two DIV_ROUND_UP() (that's just result of
historical code changes), clean up the code and fix this bug.

Cc: stable@vger.kernel.org # 3.5+
Fixes: 83f40318da ("ring-buffer: Make removal of ring buffer pages atomic")
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-05-13 16:44:20 -04:00
Steven Rostedt (Red Hat) 9b94a8fba5 ring-buffer: Use long for nr_pages to avoid overflow failures
The size variable to change the ring buffer in ftrace is a long. The
nr_pages used to update the ring buffer based on the size is int. On 64 bit
machines this can cause an overflow problem.

For example, the following will cause the ring buffer to crash:

 # cd /sys/kernel/debug/tracing
 # echo 10 > buffer_size_kb
 # echo 8556384240 > buffer_size_kb

Then you get the warning of:

 WARNING: CPU: 1 PID: 318 at kernel/trace/ring_buffer.c:1527 rb_update_pages+0x22f/0x260

Which is:

  RB_WARN_ON(cpu_buffer, nr_removed);

Note each ring buffer page holds 4080 bytes.

This is because:

 1) 10 causes the ring buffer to have 3 pages.
    (10kb requires 3 * 4080 pages to hold)

 2) (2^31 / 2^10  + 1) * 4080 = 8556384240
    The value written into buffer_size_kb is shifted by 10 and then passed
    to ring_buffer_resize(). 8556384240 * 2^10 = 8761737461760

 3) The size passed to ring_buffer_resize() is then divided by BUF_PAGE_SIZE
    which is 4080. 8761737461760 / 4080 = 2147484672

 4) nr_pages is subtracted from the current nr_pages (3) and we get:
    2147484669. This value is saved in a signed integer nr_pages_to_update

 5) 2147484669 is greater than 2^31 but smaller than 2^32, a signed int
    turns into the value of -2147482627

 6) As the value is a negative number, in update_pages_handler() it is
    negated and passed to rb_remove_pages() and 2147482627 pages will
    be removed, which is much larger than 3 and it causes the warning
    because not all the pages asked to be removed were removed.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=118001

Cc: stable@vger.kernel.org # 2.6.28+
Fixes: 7a8e76a382 ("tracing: unified trace buffer")
Reported-by: Hao Qin <QEver.cn@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-05-13 11:12:20 -04:00
Ingo Molnar d2950158d0 Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-11 16:56:38 +02:00
Shaohua Li 8d1547e08d blktrace: add missed mask name
BLK_TC_NOTIFY is missed in mask_maps, so we can't print out notify or
set mask with 'notify' name.

Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-05-10 08:41:36 -06:00
Shaohua Li b7d7641e2a blktrace: delete garbage for message trace
commit f4a1d08ce6 introduces a regression. Originally for
BLK_TN_MESSAGE, we add message in trace and return. The commit ignores
the early return and add garbage info.

Signed-off-by: Shaohua Li <shli@fb.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-05-10 08:41:34 -06:00
David S. Miller e800072c18 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
In netdevice.h we removed the structure in net-next that is being
changes in 'net'.  In macsec.c and rtnetlink.c we have overlaps
between fixes in 'net' and the u64 attribute changes in 'net-next'.

The mlx5 conflicts have to do with vxlan support dependencies.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-09 15:59:24 -04:00
Steven Rostedt (Red Hat) 0fc1b09ff1 tracing: Use temp buffer when filtering events
Filtering of events requires the data to be written to the ring buffer
before it can be decided to filter or not. This is because the parameters of
the filter are based on the result that is written to the ring buffer and
not on the parameters that are passed into the trace functions.

The ftrace ring buffer is optimized for writing into the ring buffer and
committing. The discard procedure used when filtering decides the event
should be discarded is much more heavy weight. Thus, using a temporary
filter when filtering events can speed things up drastically.

Without a temp buffer we have:

 # trace-cmd start -p nop
 # perf stat -r 10 hackbench 50
       0.790706626 seconds time elapsed ( +-  0.71% )

 # trace-cmd start -e all
 # perf stat -r 10 hackbench 50
       1.566904059 seconds time elapsed ( +-  0.27% )

 # trace-cmd start -e all -f 'common_preempt_count==20'
 # perf stat -r 10 hackbench 50
       1.690598511 seconds time elapsed ( +-  0.19% )

 # trace-cmd start -e all -f 'common_preempt_count!=20'
 # perf stat -r 10 hackbench 50
       1.707486364 seconds time elapsed ( +-  0.30% )

The first run above is without any tracing, just to get a based figure.
hackbench takes ~0.79 seconds to run on the system.

The second run enables tracing all events where nothing is filtered. This
increases the time by 100% and hackbench takes 1.57 seconds to run.

The third run filters all events where the preempt count will equal "20"
(this should never happen) thus all events are discarded. This takes 1.69
seconds to run. This is 10% slower than just committing the events!

The last run enables all events and filters where the filter will commit all
events, and this takes 1.70 seconds to run. The filtering overhead is
approximately 10%. Thus, the discard and commit of an event from the ring
buffer may be about the same time.

With this patch, the numbers change:

 # trace-cmd start -p nop
 # perf stat -r 10 hackbench 50
       0.778233033 seconds time elapsed ( +-  0.38% )

 # trace-cmd start -e all
 # perf stat -r 10 hackbench 50
       1.582102692 seconds time elapsed ( +-  0.28% )

 # trace-cmd start -e all -f 'common_preempt_count==20'
 # perf stat -r 10 hackbench 50
       1.309230710 seconds time elapsed ( +-  0.22% )

 # trace-cmd start -e all -f 'common_preempt_count!=20'
 # perf stat -r 10 hackbench 50
       1.786001924 seconds time elapsed ( +-  0.20% )

The first run is again the base with no tracing.

The second run is all tracing with no filtering. It is a little slower, but
that may be well within the noise.

The third run shows that discarding all events only took 1.3 seconds. This
is a speed up of 23%! The discard is much faster than even the commit.

The one downside is shown in the last run. Events that are not discarded by
the filter will take longer to add, this is due to the extra copy of the
event.

Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-05-03 17:59:24 -04:00
Chunyu Hu 854145e0a8 tracing: Don't display trigger file for events that can't be enabled
Currently register functions for events will be called
through the 'reg' field of event class directly without
any check when seting up triggers.

Triggers for events that don't support register through
debug fs (events under events/ftrace are for trace-cmd to
read event format, and most of them don't have a register
function except events/ftrace/functionx) can't be enabled
at all, and an oops will be hit when setting up trigger
for those events, so just not creating them is an easy way
to avoid the oops.

Link: http://lkml.kernel.org/r/1462275274-3911-1-git-send-email-chuhu@redhat.com

Cc: stable@vger.kernel.org # 3.14+
Fixes: 85f2b08268 ("tracing: Add basic event trigger framework")
Signed-off-by: Chunyu Hu <chuhu@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-05-03 12:59:30 -04:00
Steven Rostedt (Red Hat) dcb0b5575d tracing: Remove TRACE_EVENT_FL_USE_CALL_FILTER logic
Nothing sets TRACE_EVENT_FL_USE_CALL_FILTER anymore. Remove it.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-05-02 21:30:04 -04:00
Steven Rostedt (Red Hat) 904d1857ad tracing: Remove unused function trace_current_buffer_lock_reserve()
trace_current_buffer_lock_reserve() has no more users. Remove it.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-29 18:11:54 -04:00
Steven Rostedt (Red Hat) 9b9db27505 tracing: Remove one use of trace_current_buffer_lock_reserve()
The only user of trace_current_buffer_lock_reserve() is in the boot up self
tests. Restructure the code a little to have that code use what everything
else uses: trace_event_buffer_lock_reserve().

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-29 18:10:21 -04:00
Steven Rostedt (Red Hat) 33fddff24d tracing: Have trace_buffer_unlock_commit() call the _regs version with NULL
There's no real difference between trace_buffer_unlock_commit() and
trace_buffer_unlock_commit_regs() except that the former passes NULL to
ftrace_stack_trace() instead of regs. Have the former be a static inline of
the latter which passes NULL for regs.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-29 17:44:01 -04:00
Steven Rostedt (Red Hat) a9fe48dcde tracing: Remove unused function trace_current_buffer_discard_commit()
The function trace_current_buffer_discard_commit() has no callers, remove
it.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-29 16:14:13 -04:00
Steven Rostedt (Red Hat) fa66ddb870 tracing: Move trace_buffer_unlock_commit{_regs}() to local header
The functions trace_buffer_unlock_commit() and the _regs() version are only
used within the kernel/trace directory. Move them to the local header and
remove the export as well.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-29 16:14:12 -04:00
Steven Rostedt (Red Hat) 9cbb1506ab tracing: Fold filter_check_discard() into its only user
The function filter_check_discard() is small and only called by one user,
its code can be folded into that one caller and make the code a bit less
comlplex.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-29 16:14:08 -04:00
Steven Rostedt (Red Hat) 65da9a0a3b tracing: Make filter_check_discard() local
Nothing outside of the tracing directory calls filter_check_discard() or
check_filter_check_discard(). They should not be called by modules. Move
their prototypes into the local tracing header and remove their
EXPORT_SYMBOL() macros.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-27 10:13:46 -04:00
Steven Rostedt (Red Hat) dad56ee742 tracing: Move event_trigger_unlock_commit{_regs}() to local header
The functions event_trigger_unlock_commit() and
event_trigger_unlock_commit_regs() are no longer used outside the tracing
system. Move them out of the generic headers and into the local one.

Along with __event_trigger_test_discard() that is only used by them.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-26 21:24:53 -04:00
Thiago Jung Bauermann 7132e2d669 ftrace: Match dot symbols when searching functions on ppc64
In the ppc64 big endian ABI, function symbols point to function
descriptors. The symbols which point to the function entry points
have a dot in front of the function name. Consequently, when the
ftrace filter mechanism searches for the symbol corresponding to
an entry point address, it gets the dot symbol.

As a result, ftrace filter users have to be aware of this ABI detail on
ppc64 and prepend a dot to the function name when setting the filter.

The perf probe command insulates the user from this by ignoring the dot
in front of the symbol name when matching function names to symbols,
but the sysfs interface does not. This patch makes the ftrace filter
mechanism do the same when searching symbols.

Fixes the following failure in ftracetest's kprobe_ftrace.tc:

  .../kprobe_ftrace.tc: line 9: echo: write error: Invalid argument

That failure is on this line of kprobe_ftrace.tc:

  echo _do_fork > set_ftrace_filter

This is because there's no _do_fork entry in the functions list:

  # cat available_filter_functions | grep _do_fork
  ._do_fork

This change introduces no regressions on the perf and ftracetest
testsuite results.

Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-04-27 09:47:29 +10:00
Wang Xiaoqiang 4afe6495e5 tracing: Don't use the address of the buffer array name in copy_from_user
With the following code snippet:

    ...
    char buf[64];
    ...
    if (copy_from_user(&buf, ubuf, cnt))
    ...

Even though the value of "&buf" equals "buf", but there is no need
to get the address of the "buf" again. Use "buf" instead of "&buf".

Link: http://lkml.kernel.org/r/20160418152329.18b72bea@debian

Signed-off-by: Wang Xiaoqiang <wangxq10@lzu.edu.cn>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-26 14:42:03 -04:00
Tom Zanussi 6e4cf657de tracing: Handle tracing_map_alloc_elts() error path correctly
If tracing_map_elt_alloc() fails, it will return ERR_PTR() instead of
NULL, so change the check to IS_ERROR().  We also need to set the
failed entry in the map->elts array to NULL instead of ERR_PTR() so
tracing_map_free_elts() doesn't try freeing an ERR_PTR().

tracing_map_free_elts() should also zero out what it frees so a
reentrant call won't find previously freed elements.

Link: http://lkml.kernel.org/r/f29d03b00bce3aac8cf151a8a30e6c83e5fee66d.1461610073.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-26 09:40:30 -04:00
Tom Zanussi 432480c582 tracing: Add check for NULL event field when creating hist field
Smatch flagged create_hist_field() as possibly being able to
dereference a NULL pointer, although the current code exits in all
cases where the event field could be NULL, so it's not actually a
problem.

Still, to prevent future changes to the code from overlooking new
cases, make the NULL pointer check explicit and warn once in that
case.

Link: http://lkml.kernel.org/r/cfbc003f534a3e441b4313272fd412310aba6336.1461610073.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-26 09:40:29 -04:00
Dan Carpenter 4812952f9c tracing: checking for NULL instead of IS_ERR()
tracing_map_elt_alloc() returns ERR_PTRs on error, never NULL.

Fixes: 08d43a5fa0 ('tracing: Add lock-free tracing_map')
Link: http://lkml.kernel.org/r/20160423102347.GA11136@mwanda

Acked-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-26 09:40:20 -04:00
Steven Rostedt (Red Hat) 205506228b tracing: Do not inherit event-fork option for instances
As the event-fork option requires doing work when enabled and disabled, it
can not be passed down to created instances. The instance must clear this
flag when it is created, and must clear it when its removed.

As more options may be created with this need, a macro ZEROED_TRACE_FLAGS is
created that holds the flags that must not be inherited by the top level
instance, and must be cleared on removal of instances.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-25 22:40:12 -04:00
Daniel Borkmann bd570ff970 bpf: add event output helper for notifications/sampling/logging
This patch adds a new helper for cls/act programs that can push events
to user space applications. For networking, this can be f.e. for sampling,
debugging, logging purposes or pushing of arbitrary wake-up events. The
idea is similar to a43eec3042 ("bpf: introduce bpf_perf_event_output()
helper") and 39111695b1 ("samples: bpf: add bpf_perf_event_output example").

The eBPF program utilizes a perf event array map that user space populates
with fds from perf_event_open(), the eBPF program calls into the helper
f.e. as skb_event_output(skb, &my_map, BPF_F_CURRENT_CPU, raw, sizeof(raw))
so that the raw data is pushed into the fd f.e. at the map index of the
current CPU.

User space can poll/mmap/etc on this and has a data channel for receiving
events that can be post-processed. The nice thing is that since the eBPF
program and user space application making use of it are tightly coupled,
they can define their own arbitrary raw data format and what/when they
want to push.

While f.e. packet headers could be one part of the meta data that is being
pushed, this is not a substitute for things like packet sockets as whole
packet is not being pushed and push is only done in a single direction.
Intention is more of a generically usable, efficient event pipe to applications.
Workflow is that tc can pin the map and applications can attach themselves
e.g. after cls/act setup to one or multiple map slots, demuxing is done by
the eBPF program.

Adding this facility is with minimal effort, it reuses the helper
introduced in a43eec3042 ("bpf: introduce bpf_perf_event_output() helper")
and we get its functionality for free by overloading its BPF_FUNC_ identifier
for cls/act programs, ctx is currently unused, but will be made use of in
future. Example will be added to iproute2's BPF example files.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-19 20:26:11 -04:00
Daniel Borkmann 1e33759c78 bpf, trace: add BPF_F_CURRENT_CPU flag for bpf_perf_event_output
Add a BPF_F_CURRENT_CPU flag to optimize the use-case where user space has
per-CPU ring buffers and the eBPF program pushes the data into the current
CPU's ring buffer which saves us an extra helper function call in eBPF.
Also, make sure to properly reserve the remaining flags which are not used.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-19 20:26:11 -04:00
Steven Rostedt (Red Hat) d50c744ecd tracing: Fix unsigned comparison to zero in hist trigger code
Fengguang Wu's bot found two comparisons of unsigned integers to zero. These
were real bugs, as it would miss error conditions returned to zero.

trace_events_hist.c:426:6-9: WARNING: Unsigned expression compared with zero: idx < 0
trace_events_hist.c:568:5-14: WARNING: Unsigned expression compared with zero: n_entries < 0

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 18:56:05 -04:00
Namhyung Kim 4b94f5b7b4 tracing: Add hist trigger 'log2' modifier
Allow users to have numeric fields displayed as log2 values in case
value range is very wide by appending '.log2' to field names.

For example,

  # echo 'hist:key=bytes_req' > kmalloc/trigger
  # cat kmalloc/hist

  { bytes_req:        504 } hitcount:          1
  { bytes_req:         11 } hitcount:          1
  { bytes_req:        104 } hitcount:          1
  { bytes_req:         48 } hitcount:          1
  { bytes_req:       2048 } hitcount:          1
  { bytes_req:       4096 } hitcount:          1
  { bytes_req:        240 } hitcount:          1
  { bytes_req:        392 } hitcount:          1
  { bytes_req:         13 } hitcount:          1
  { bytes_req:         28 } hitcount:          1
  { bytes_req:         12 } hitcount:          1
  { bytes_req:         64 } hitcount:          2
  { bytes_req:        128 } hitcount:          2
  { bytes_req:         32 } hitcount:          2
  { bytes_req:          8 } hitcount:         11
  { bytes_req:         10 } hitcount:         13
  { bytes_req:         24 } hitcount:         25
  { bytes_req:        160 } hitcount:         29
  { bytes_req:         16 } hitcount:         33
  { bytes_req:         80 } hitcount:         36

When using '.log2' modifier, the output looks like:

  # echo 'hist:key=bytes_req.log2' > kmalloc/trigger
  # cat kmalloc/hist

  { bytes_req: ~ 2^12 } hitcount:          1
  { bytes_req: ~ 2^11 } hitcount:          1
  { bytes_req: ~ 2^9  } hitcount:          2
  { bytes_req: ~ 2^6  } hitcount:          3
  { bytes_req: ~ 2^3  } hitcount:         13
  { bytes_req: ~ 2^5  } hitcount:         19
  { bytes_req: ~ 2^8  } hitcount:         49
  { bytes_req: ~ 2^7  } hitcount:         57
  { bytes_req: ~ 2^4  } hitcount:         74

Link: http://lkml.kernel.org/r/7ff396b246c6a881f46b979735fddf05a0d6c71a.1457029949.git.tom.zanussi@linux.intel.com

Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-04-19 18:56:03 -04:00