<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux/kernel/trace/trace_event_perf.c, branch v4.15</title>
<subtitle>Mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/
</subtitle>
<id>https://git.shady.money/linux/atom?h=v4.15</id>
<link rel='self' href='https://git.shady.money/linux/atom?h=v4.15'/>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/'/>
<updated>2017-10-16T22:13:28Z</updated>
<entry>
<title>perf/ftrace: Small cleanup</title>
<updated>2017-10-16T22:13:28Z</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2017-10-11T07:45:31Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=1dd311e6dcda4020c603bcf9f390a577d439d509'/>
<id>urn:sha1:1dd311e6dcda4020c603bcf9f390a577d439d509</id>
<content type='text'>
ops-&gt;flags _should_ be 0 at this point, so setting the flag using
bitwise or is a bit daft.

Link: http://lkml.kernel.org/r/20171011080224.315585202@infradead.org

Requested-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>perf/ftrace: Fix function trace events</title>
<updated>2017-10-16T22:12:21Z</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2017-10-10T15:15:47Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=466c81c45b650deca213fda3d0ec4761667379a9'/>
<id>urn:sha1:466c81c45b650deca213fda3d0ec4761667379a9</id>
<content type='text'>
The function-trace &lt;-&gt; perf interface is a tad messed up. Where all
the other trace &lt;-&gt; perf interfaces use a single trace hook
registration and use per-cpu RCU based hlist to iterate the events,
function-trace actually needs multiple hook registrations in order to
minimize function entry patching when filters are present.

The end result is that we iterate events both on the trace hook and on
the hlist, which results in reporting events multiple times.

Since function-trace cannot use the regular scheme, fix it the other
way around, use singleton hlists.

Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>perf/ftrace: Revert ("perf/ftrace: Fix double traces of perf on ftrace:function")</title>
<updated>2017-10-16T22:11:02Z</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2017-10-11T07:45:29Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=8fd0fbbe8888f295eb34172a7e47bf7d3a0a4687'/>
<id>urn:sha1:8fd0fbbe8888f295eb34172a7e47bf7d3a0a4687</id>
<content type='text'>
Revert commit:

  75e8387685f6 ("perf/ftrace: Fix double traces of perf on ftrace:function")

The reason I instantly stumbled on that patch is that it only addresses the
ftrace situation and doesn't mention the other _5_ places that use this
interface. It doesn't explain why those don't have the problem and if not, why
their solution doesn't work for ftrace.

It doesn't, but this is just putting more duct tape on.

Link: http://lkml.kernel.org/r/20171011080224.200565770@infradead.org

Cc: Zhou Chengming &lt;zhouchengming1@huawei.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>perf/ftrace: Fix double traces of perf on ftrace:function</title>
<updated>2017-08-29T11:29:29Z</updated>
<author>
<name>Zhou Chengming</name>
<email>zhouchengming1@huawei.com</email>
</author>
<published>2017-08-25T13:49:37Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=75e8387685f6c65feb195a4556110b58f852b848'/>
<id>urn:sha1:75e8387685f6c65feb195a4556110b58f852b848</id>
<content type='text'>
When running perf on the ftrace:function tracepoint, there is a bug
which can be reproduced by:

  perf record -e ftrace:function -a sleep 20 &amp;
  perf record -e ftrace:function ls
  perf script

              ls 10304 [005]   171.853235: ftrace:function:
  perf_output_begin
              ls 10304 [005]   171.853237: ftrace:function:
  perf_output_begin
              ls 10304 [005]   171.853239: ftrace:function:
  task_tgid_nr_ns
              ls 10304 [005]   171.853240: ftrace:function:
  task_tgid_nr_ns
              ls 10304 [005]   171.853242: ftrace:function:
  __task_pid_nr_ns
              ls 10304 [005]   171.853244: ftrace:function:
  __task_pid_nr_ns

We can see that all the function traces are doubled.

The problem is caused by the inconsistency of the register
function perf_ftrace_event_register() with the probe function
perf_ftrace_function_call(). The former registers one probe
for every perf_event. And the latter handles all perf_events
on the current cpu. So when two perf_events on the current cpu,
the traces of them will be doubled.

So this patch adds an extra parameter "event" for perf_tp_event,
only send sample data to this event when it's not NULL.

Signed-off-by: Zhou Chengming &lt;zhouchengming1@huawei.com&gt;
Reviewed-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Acked-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: acme@kernel.org
Cc: alexander.shishkin@linux.intel.com
Cc: huawei.libin@huawei.com
Link: http://lkml.kernel.org/r/1503668977-12526-1-git-send-email-zhouchengming1@huawei.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next</title>
<updated>2016-05-17T23:26:30Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2016-05-17T23:26:30Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=a7fd20d1c476af4563e66865213474a2f9f473a4'/>
<id>urn:sha1:a7fd20d1c476af4563e66865213474a2f9f473a4</id>
<content type='text'>
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
  ...
</content>
</entry>
<entry>
<title>perf: split perf_trace_buf_prepare into alloc and update parts</title>
<updated>2016-04-08T01:04:26Z</updated>
<author>
<name>Alexei Starovoitov</name>
<email>ast@fb.com</email>
</author>
<published>2016-04-07T01:43:24Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=1e1dcd93b468901e114f279c94a0b356adc5e7cd'/>
<id>urn:sha1:1e1dcd93b468901e114f279c94a0b356adc5e7cd</id>
<content type='text'>
split allows to move expensive update of 'struct trace_entry' to later phase.
Repurpose unused 1st argument of perf_tp_event() to indicate event type.

While splitting use temp variable 'rctx' instead of '*rctx' to avoid
unnecessary loads done by the compiler due to -fno-strict-aliasing

Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>perf: optimize perf_fetch_caller_regs</title>
<updated>2016-04-08T01:04:26Z</updated>
<author>
<name>Alexei Starovoitov</name>
<email>ast@fb.com</email>
</author>
<published>2016-04-07T01:43:22Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=ec5e099d6e941668d121ea9ca7057f4fa00830b0'/>
<id>urn:sha1:ec5e099d6e941668d121ea9ca7057f4fa00830b0</id>
<content type='text'>
avoid memset in perf_fetch_caller_regs, since it's the critical path of all tracepoints.
It's called from perf_sw_event_sched, perf_event_task_sched_in and all of perf_trace_##call
with this_cpu_ptr(&amp;__perf_regs[..]) which are zero initialized by perpcu init logic and
subsequent call to perf_arch_fetch_caller_regs initializes the same fields on all archs,
so we can safely drop memset from all of the above cases and move it into
perf_ftrace_function_call that calls it with stack allocated pt_regs.

Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>ftrace/perf: Check sample types only for sampling events</title>
<updated>2016-03-31T08:30:45Z</updated>
<author>
<name>Jiri Olsa</name>
<email>jolsa@kernel.org</email>
</author>
<published>2016-03-16T14:34:29Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=0a74c5b3d20d2a8693848b6ae4f1a97624f5b781'/>
<id>urn:sha1:0a74c5b3d20d2a8693848b6ae4f1a97624f5b781</id>
<content type='text'>
Currently we check sample type for ftrace:function events
even if it's not created as a sampling event. That prevents
creating ftrace_function event in counting mode.

Make sure we check sample types only for sampling events.

Before:
  $ sudo perf stat -e ftrace:function ls
  ...

   Performance counter stats for 'ls':

     &lt;not supported&gt;      ftrace:function

         0.001983662 seconds time elapsed

After:
  $ sudo perf stat -e ftrace:function ls
  ...

   Performance counter stats for 'ls':

              44,498      ftrace:function

         0.037534722 seconds time elapsed

Suggested-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Signed-off-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Acked-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Arnaldo Carvalho de Melo &lt;acme@kernel.org&gt;
Cc: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Vince Weaver &lt;vincent.weaver@maine.edu&gt;
Link: http://lkml.kernel.org/r/1458138873-1553-2-git-send-email-jolsa@kernel.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'trace-v4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace</title>
<updated>2016-01-13T04:04:15Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2016-01-13T04:04:15Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=c17488d06666153a14dd3f21bd10eba58383f6c1'/>
<id>urn:sha1:c17488d06666153a14dd3f21bd10eba58383f6c1</id>
<content type='text'>
Pull tracing updates from Steven Rostedt:
 "Not much new with tracing for this release.  Mostly just clean ups and
  minor fixes.

  Here's what else is new:

   - A new TRACE_EVENT_FN_COND macro, combining both _FN and _COND for
     those that want both.

   - New selftest to test the instance create and delete

   - Better debug output when ftrace fails"

* tag 'trace-v4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (24 commits)
  ftrace: Fix the race between ftrace and insmod
  ftrace: Add infrastructure for delayed enabling of module functions
  x86: ftrace: Fix the comments for ftrace_modify_code_direct()
  tracing: Fix comment to use tracing_on over tracing_enable
  metag: ftrace: Fix the comments for ftrace_modify_code
  sh: ftrace: Fix the comments for ftrace_modify_code()
  ia64: ftrace: Fix the comments for ftrace_modify_code()
  ftrace: Clean up ftrace_module_init() code
  ftrace: Join functions ftrace_module_init() and ftrace_init_module()
  tracing: Introduce TRACE_EVENT_FN_COND macro
  tracing: Use seq_buf_used() in seq_buf_to_user() instead of len
  bpf: Constify bpf_verifier_ops structure
  ftrace: Have ftrace_ops_get_func() handle RCU and PER_CPU flags too
  ftrace: Remove use of control list and ops
  ftrace: Fix output of enabled_functions for showing tramp
  ftrace: Fix a typo in comment
  ftrace: Show all tramps registered to a record on ftrace_bug()
  ftrace: Add variable ftrace_expected for archs to show expected code
  ftrace: Add new type to distinguish what kind of ftrace_bug()
  tracing: Update cond flag when enabling or disabling a trigger
  ...
</content>
</entry>
<entry>
<title>ftrace: Remove use of control list and ops</title>
<updated>2015-12-23T19:27:18Z</updated>
<author>
<name>Steven Rostedt (Red Hat)</name>
<email>rostedt@goodmis.org</email>
</author>
<published>2015-11-30T22:23:39Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=ba27f2bc731135a0396f3968bdddb54f3bc72e64'/>
<id>urn:sha1:ba27f2bc731135a0396f3968bdddb54f3bc72e64</id>
<content type='text'>
Currently perf has its own list function within the ftrace infrastructure
that seems to be used only to allow for it to have per-cpu disabling as well
as a check to make sure that it's not called while RCU is not watching. It
uses something called the "control_ops" which is used to iterate over ops
under it with the control_list_func().

The problem is that this control_ops and control_list_func unnecessarily
complicates the code. By replacing FTRACE_OPS_FL_CONTROL with two new flags
(FTRACE_OPS_FL_RCU and FTRACE_OPS_FL_PER_CPU) we can remove all the code
that is special with the control ops and add the needed checks within the
generic ftrace_list_func().

Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
</entry>
</feed>
