Commit Graph

15586 Commits

Author SHA1 Message Date
Stefano Brivio
56fd865f46 selftests: pmtu: Introduce FoU and GUE PMTU exceptions tests
Introduce eight tests, for FoU and GUE, with IPv4 and IPv6 payload,
on IPv4 and IPv6 transport, that check that PMTU exceptions are created
with the right value when exceeding the MTU on a link of the path.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-08 17:13:08 -08:00
Stefano Brivio
ce7336610c selftests: pmtu: Introduce tests for IPv4/IPv6 over GENEVE over IPv4/IPv6
Use a router between endpoints, implemented via namespaces, set a low MTU
between router and destination endpoint, exceed it and check PMTU value in
route exceptions.

v2:
- Introduce IPv4 tests right away, if iproute2 doesn't support the 'df'
  link option they will be skipped (David Ahern)

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-08 17:13:08 -08:00
Stefano Brivio
582888792f selftests: pmtu: Introduce tests for IPv4/IPv6 over VXLAN over IPv4/IPv6
Use a router between endpoints, implemented via namespaces, set a low MTU
between router and destination endpoint, exceed it and check PMTU value in
route exceptions.

v2:
- Change all occurrences of VxLAN to VXLAN (Jiri Benc)
- Introduce IPv4 tests right away, if iproute2 doesn't support the 'df'
  link option they will be skipped (David Ahern)

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-08 17:13:08 -08:00
Paolo Abeni
3327a9c463 selftests: add functionals test for UDP GRO
Extends the existing udp programs to allow checking for proper
GRO aggregation/GSO size, and run the tests via a shell script, using
a veth pair with XDP program attached to trigger the GRO code path.

rfc v3 -> v1:
 - use ip route to attach the xdp helper to the veth

rfc v2 -> rfc v3:
 - add missing test program options documentation
 - fix sporatic test failures (receiver faster than sender)

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-07 16:23:05 -08:00
Paolo Abeni
e87f53b4fa selftests: add some benchmark for UDP GRO
Run on top of veth pair, using a dummy XDP program to enable the GRO.

 rfc v3 -> v1:
  - use ip route to attach the xdp helper to the veth

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-07 16:23:05 -08:00
Paolo Abeni
bd8e1afe64 selftests: add dummy xdp test helper
This trivial XDP program does nothing, but will be used by the
next patch to test the GRO path in a net namespace, leveraging
the veth XDP implementation.

It's added here, despite its 'net' usage, to avoid the duplication
of the llc-related makefile boilerplate.

rfc v3 -> v1:
 - move the helper implementation into the bpf directory, don't
   touch udpgso_bench_rx

rfc v2 -> rfc v3:
 - move 'x' option handling here

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-07 16:23:05 -08:00
Paolo Abeni
0a9ac2e954 selftests: add GRO support to udp bench rx program
And fix a couple of buglets (port option processing,
clean termination on SIGINT). This is preparatory work
for GRO tests.

rfc v2 -> rfc v3:
 - use ETH_MAX_MTU

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-07 16:23:05 -08:00
Linus Torvalds
601a88077c Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "A number of fixes and some late updates:

   - make in_compat_syscall() behavior on x86-32 similar to other
     platforms, this touches a number of generic files but is not
     intended to impact non-x86 platforms.

   - objtool fixes

   - PAT preemption fix

   - paravirt fixes/cleanups

   - cpufeatures updates for new instructions

   - earlyprintk quirk

   - make microcode version in sysfs world-readable (it is already
     world-readable in procfs)

   - minor cleanups and fixes"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  compat: Cleanup in_compat_syscall() callers
  x86/compat: Adjust in_compat_syscall() to generic code under !COMPAT
  objtool: Support GCC 9 cold subfunction naming scheme
  x86/numa_emulation: Fix uniform-split numa emulation
  x86/paravirt: Remove unused _paravirt_ident_32
  x86/mm/pat: Disable preemption around __flush_tlb_all()
  x86/paravirt: Remove GPL from pv_ops export
  x86/traps: Use format string with panic() call
  x86: Clean up 'sizeof x' => 'sizeof(x)'
  x86/cpufeatures: Enumerate MOVDIR64B instruction
  x86/cpufeatures: Enumerate MOVDIRI instruction
  x86/earlyprintk: Add a force option for pciserial device
  objtool: Support per-function rodata sections
  x86/microcode: Make revision and processor flags world-readable
2018-11-03 18:25:17 -07:00
Linus Torvalds
01897f3e05 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates and fixes from Ingo Molnar:
 "These are almost all tooling updates: 'perf top', 'perf trace' and
  'perf script' fixes and updates, an UAPI header sync with the merge
  window versions, license marker updates, much improved Sparc support
  from David Miller, and a number of fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (66 commits)
  perf intel-pt/bts: Calculate cpumode for synthesized samples
  perf intel-pt: Insert callchain context into synthesized callchains
  perf tools: Don't clone maps from parent when synthesizing forks
  perf top: Start display thread earlier
  tools headers uapi: Update linux/if_link.h header copy
  tools headers uapi: Update linux/netlink.h header copy
  tools headers: Sync the various kvm.h header copies
  tools include uapi: Update linux/mmap.h copy
  perf trace beauty: Use the mmap flags table generated from headers
  perf beauty: Wire up the mmap flags table generator to the Makefile
  perf beauty: Add a generator for MAP_ mmap's flag constants
  tools include uapi: Update asound.h copy
  tools arch uapi: Update asm-generic/unistd.h and arm64 unistd.h copies
  tools include uapi: Update linux/fs.h copy
  perf callchain: Honour the ordering of PERF_CONTEXT_{USER,KERNEL,etc}
  perf cs-etm: Correct CPU mode for samples
  perf unwind: Take pgoff into account when reporting elf to libdwfl
  perf top: Do not use overwrite mode by default
  perf top: Allow disabling the overwrite mode
  perf trace: Beautify mount's first pathname arg
  ...
2018-11-03 18:13:43 -07:00
Ingo Molnar
23a12ddee1 Merge branch 'core/urgent' into x86/urgent, to pick up objtool fix
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-11-03 23:42:16 +01:00
Linus Torvalds
b69f9e17a5 powerpc fixes for 4.20 #2
Some things that I missed due to travel, or that came in late.
 
 Two fixes also going to stable:
 
  - A revert of a buggy change to the 8xx TLB miss handlers.
 
  - Our flushing of SPE (Signal Processing Engine) registers on fork was broken.
 
 Other changes:
 
  - A change to the KVM decrementer emulation to use proper APIs.
 
  - Some cleanups to the way we do code patching in the 8xx code.
 
  - Expose the maximum possible memory for the system in /proc/powerpc/lparcfg.
 
  - Merge some updates from Scott: "a couple device tree updates, and a fix for a
    missing prototype warning."
 
 A few other minor fixes and a handful of fixes for our selftests.
 
 Thanks to:
   Aravinda Prasad, Breno Leitao, Camelia Groza, Christophe Leroy, Felipe Rechia,
   Joel Stanley, Naveen N. Rao, Paul Mackerras, Scott Wood, Tyrel Datwyler.
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Merge tag 'powerpc-4.20-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "Some things that I missed due to travel, or that came in late.

  Two fixes also going to stable:

   - A revert of a buggy change to the 8xx TLB miss handlers.

   - Our flushing of SPE (Signal Processing Engine) registers on fork
     was broken.

  Other changes:

   - A change to the KVM decrementer emulation to use proper APIs.

   - Some cleanups to the way we do code patching in the 8xx code.

   - Expose the maximum possible memory for the system in
     /proc/powerpc/lparcfg.

   - Merge some updates from Scott: "a couple device tree updates, and a
     fix for a missing prototype warning"

  A few other minor fixes and a handful of fixes for our selftests.

  Thanks to: Aravinda Prasad, Breno Leitao, Camelia Groza, Christophe
  Leroy, Felipe Rechia, Joel Stanley, Naveen N. Rao, Paul Mackerras,
  Scott Wood, Tyrel Datwyler"

* tag 'powerpc-4.20-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (21 commits)
  selftests/powerpc: Fix compilation issue due to asm label
  selftests/powerpc/cache_shape: Fix out-of-tree build
  selftests/powerpc/switch_endian: Fix out-of-tree build
  selftests/powerpc/pmu: Link ebb tests with -no-pie
  selftests/powerpc/signal: Fix out-of-tree build
  selftests/powerpc/ptrace: Fix out-of-tree build
  powerpc/xmon: Relax frame size for clang
  selftests: powerpc: Fix warning for security subdir
  selftests/powerpc: Relax L1d miss targets for rfi_flush test
  powerpc/process: Fix flush_all_to_thread for SPE
  powerpc/pseries: add missing cpumask.h include file
  selftests/powerpc: Fix ptrace tm failure
  KVM: PPC: Use exported tb_to_ns() function in decrementer emulation
  powerpc/pseries: Export maximum memory value
  powerpc/8xx: Use patch_site for perf counters setup
  powerpc/8xx: Use patch_site for memory setup patching
  powerpc/code-patching: Add a helper to get the address of a patch_site
  Revert "powerpc/8xx: Use L1 entry APG to handle _PAGE_ACCESSED for CONFIG_SWAP"
  powerpc/8xx: add missing header in 8xx_mmu.c
  powerpc/8xx: Add DT node for using the SEC engine of the MPC885
  ...
2018-11-02 09:19:35 -07:00
Linus Torvalds
82aa467151 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) BPF verifier fixes from Daniel Borkmann.

 2) HNS driver fixes from Huazhong Tan.

 3) FDB only works for ethernet devices, reject attempts to install FDB
    rules for others. From Ido Schimmel.

 4) Fix spectre V1 in vhost, from Jason Wang.

 5) Don't pass on-stack object to irq_set_affinity_hint() in mvpp2
    driver, from Marc Zyngier.

 6) Fix mlx5e checksum handling when RXFCS is enabled, from Eric
    Dumazet.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (49 commits)
  openvswitch: Fix push/pop ethernet validation
  net: stmmac: Fix stmmac_mdio_reset() when building stmmac as modules
  bpf: test make sure to run unpriv test cases in test_verifier
  bpf: add various test cases to test_verifier
  bpf: don't set id on after map lookup with ptr_to_map_val return
  bpf: fix partial copy of map_ptr when dst is scalar
  libbpf: Fix compile error in libbpf_attach_type_by_name
  kselftests/bpf: use ping6 as the default ipv6 ping binary if it exists
  selftests: mlxsw: qos_mc_aware: Add a test for UC awareness
  selftests: mlxsw: qos_mc_aware: Tweak for min shaper
  mlxsw: spectrum: Set minimum shaper on MC TCs
  mlxsw: reg: QEEC: Add minimum shaper fields
  net: hns3: bugfix for rtnl_lock's range in the hclgevf_reset()
  net: hns3: bugfix for rtnl_lock's range in the hclge_reset()
  net: hns3: bugfix for handling mailbox while the command queue reinitialized
  net: hns3: fix incorrect return value/type of some functions
  net: hns3: bugfix for hclge_mdio_write and hclge_mdio_read
  net: hns3: bugfix for is_valid_csq_clean_head()
  net: hns3: remove unnecessary queue reset in the hns3_uninit_all_ring()
  net: hns3: bugfix for the initialization of command queue's spin lock
  ...
2018-11-01 09:16:01 -07:00
Josh Poimboeuf
bcb6fb5da7 objtool: Support GCC 9 cold subfunction naming scheme
Starting with GCC 8, a lot of unlikely code was moved out of line to
"cold" subfunctions in .text.unlikely.

For example, the unlikely bits of:

  irq_do_set_affinity()

are moved out to the following subfunction:

  irq_do_set_affinity.cold.49()

Starting with GCC 9, the numbered suffix has been removed.  So in the
above example, the cold subfunction is instead:

  irq_do_set_affinity.cold()

Tweak the objtool subfunction detection logic so that it detects both
GCC 8 and GCC 9 naming schemes.

Reported-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/015e9544b1f188d36a7f02fa31e9e95629aa5f50.1541040800.git.jpoimboe@redhat.com
2018-11-01 09:55:38 +01:00
David S. Miller
df975da4e5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2018-11-01

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) Fix tcp_bpf_recvmsg() to return -EAGAIN instead of 0 in non-blocking
   case when no data is available yet, from John.

2) Fix a compilation error in libbpf_attach_type_by_name() when compiled
   with clang 3.8, from Andrey.

3) Fix a partial copy of map pointer on scalar alu and remove id
   generation for RET_PTR_TO_MAP_VALUE return types, from Daniel.

4) Add unlimited memlock limit for kernel selftest's flow_dissector_load
   program, from Yonghong.

5) Fix ping for some BPF shell based kselftests where distro does not
   ship "ping -6" anymore, from Li.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-31 17:34:08 -07:00
Daniel Borkmann
832c6f2c29 bpf: test make sure to run unpriv test cases in test_verifier
Right now unprivileged tests are never executed as a BPF test run,
only loaded. Allow for running them as well so that we can check
the outcome and probe for regressions.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-31 16:53:17 -07:00
Daniel Borkmann
2683f4128c bpf: add various test cases to test_verifier
Add some more map related test cases to test_verifier kselftest
to improve test coverage. Summary: 1012 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-31 16:53:17 -07:00
Naveen N. Rao
1936f094e1 selftests/powerpc: Fix compilation issue due to asm label
We are using 'dscr_insn' as a label in inline asm to identify if a
SIGILL was generated by the mtspr instruction at that point. However,
with inline assembly, the compiler is still free to duplicate the asm
statement for optimization purposes, which results in the label being
defined twice with the error:
	/tmp/ccerQCql.s:874: Error: symbol `dscr_insn' is already defined

With different compiler versions, we may also see:
	/tmp/ccJzLDlN.o:(.toc+0x0): undefined reference to `dscr_insn'

Remove the use of the label in the inline assembly. Instead, just look
for the offending instruction in the signal handler.

Fixes: d2bf793237 ("selftests/powerpc: Add test to verify rfi flush across a system call")
Reported-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Tested-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-11-01 10:06:03 +11:00
Andrey Ignatov
3615353218 libbpf: Fix compile error in libbpf_attach_type_by_name
Arnaldo Carvalho de Melo reported build error in libbpf when clang
version 3.8.1-24 (tags/RELEASE_381/final) is used:

libbpf.c:2201:36: error: comparison of constant -22 with expression of
type 'const enum bpf_attach_type' is always false
[-Werror,-Wtautological-constant-out-of-range-compare]
                if (section_names[i].attach_type == -EINVAL)
                    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^  ~~~~~~~
1 error generated.

Fix the error by keeping "is_attachable" property of a program in a
separate struct field instead of trying to use attach_type itself.

Fixes: 956b620fcf ("libbpf: Introduce libbpf_attach_type_by_name")
Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-31 23:06:17 +01:00
Li Zhijian
deee2cae27 kselftests/bpf: use ping6 as the default ipv6 ping binary if it exists
ping binary on some distros doesn't support "ping -6" anymore.

Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-31 23:05:30 +01:00
Petr Machata
a5ee171d08 selftests: mlxsw: qos_mc_aware: Add a test for UC awareness
In a previous patch, mlxsw was updated to configure a minimum bandwidth
allowance on MC TCs. Test that this indeed fixes the problem of UC
traffic overload pushing out all MC traffic.

Fixes: b5638d46c9 ("selftests: mlxsw: Add a test for UC behavior under MC flood")
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-31 12:56:59 -07:00
Petr Machata
8f3f09358c selftests: mlxsw: qos_mc_aware: Tweak for min shaper
Since the minimum shaper is now being enabled for MC TCs, it's
unreasonable to expect no UC traffic loss. Minimal min shaper value is
200Mbps, which is 20% of the 1Gbps that this test configures on egress.
To cover for glitches, tolerate up to 25% UC degradation under MC
overload.

Fixes: b5638d46c9 ("selftests: mlxsw: Add a test for UC behavior under MC flood")
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-31 12:56:59 -07:00
Adrian Hunter
5d4f0edaa3 perf intel-pt/bts: Calculate cpumode for synthesized samples
In the absence of a fallback, samples must provide a correct cpumode for
the 'ip'. Do that now there is no fallback.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: stable@vger.kernel.org # 4.19
Link: http://lkml.kernel.org/r/20181031091043.23465-6-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-10-31 12:56:26 -03:00
Adrian Hunter
242483068b perf intel-pt: Insert callchain context into synthesized callchains
In the absence of a fallback, callchains must encode also the callchain
context. Do that now there is no fallback.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: stable@vger.kernel.org # 4.19
Link: http://lkml.kernel.org/r/100ea2ec-ed14-b56d-d810-e0a6d2f4b069@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-10-31 12:54:27 -03:00
David Miller
4f8f382e63 perf tools: Don't clone maps from parent when synthesizing forks
When synthesizing FORK events, we are trying to create thread objects
for the already running tasks on the machine.

Normally, for a kernel FORK event, we want to clone the parent's maps
because that is what the kernel just did.

But when synthesizing, this should not be done.  If we do, we end up
with overlapping maps as we process the sythesized MMAP2 events that
get delivered shortly thereafter.

Use the FORK event misc flags in an internal way to signal this
situation, so we can elide the map clone when appropriate.

Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joe Mario <jmario@redhat.com>
Link: http://lkml.kernel.org/r/20181030.222404.2085088822877051075.davem@davemloft.net
[ Added comment about flag use in machine__process_fork_event(),
  use ternary op in thread__clone_map_groups() as suggested by Jiri ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-10-31 10:18:01 -03:00
David Miller
ff27a06af6 perf top: Start display thread earlier
If events are coming in at a rate such that the event processing thread
can barely keep up, our initial run of the event ring will almost never
terminate and this delays the starting of the display thread.

The screen basically stays black until the event thread can get out of
it's endless loop.

Therefore, start the display thread before we start processing the ring
buffer.

This also make sure that we always have the user requested real time
setting engaged when processing the ring.

Signed-off-by: David S. Miller <davem@davemloft.net>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20181030.223003.2242527041807905962.davem@davemloft.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-10-31 10:10:11 -03:00
Arnaldo Carvalho de Melo
76b0b80178 tools headers uapi: Update linux/if_link.h header copy
To pick the changes from:

  9163a0fc1f ("net: bridge: add support for per-port vlan stats")

And silence this build warning:

  Warning: Kernel ABI header at 'tools/include/uapi/linux/if_link.h' differs from latest version at 'include/uapi/linux/if_link.h'

Cc: Alexei Starovoitov <ast@kernel.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Leblond <eric@regit.org>
Cc: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Link: https://lkml.kernel.org/n/tip-7p53ghippywz7fqkwo3nkzet@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-10-31 09:57:54 -03:00
Arnaldo Carvalho de Melo
d45a57fff0 tools headers uapi: Update linux/netlink.h header copy
Picking the changes from:

  89d35528d1 ("netlink: Add new socket option to enable strict checking on dumps")

To silence this build warning:

  Warning: Kernel ABI header at 'tools/include/uapi/linux/netlink.h' differs from latest version at 'include/uapi/linux/netlink.h'

Cc: Alexei Starovoitov <ast@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Leblond <eric@regit.org>
Link: https://lkml.kernel.org/n/tip-1xymkfjpmhxfzrs46t8z8mjw@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-10-31 09:57:54 -03:00
Arnaldo Carvalho de Melo
827758129a tools headers: Sync the various kvm.h header copies
For powerpc, s390, x86 and the main uapi linux/kvm.h header, none of
them entail changes in tooling.

Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-avn7iy8f4tcm2y40sbsdk31m@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-10-31 09:57:53 -03:00
Arnaldo Carvalho de Melo
685626dc26 tools include uapi: Update linux/mmap.h copy
To pick up the changes from:

  20916d4636 ("mm/hugetlb: add mmap() encodings for 32MB and 512MB page sizes")

That do not entail changes in in tools, this just shows that we have to
consider bits [26:31] of flags to beautify that in tools like 'perf
trace'

This silences this perf build warning:

  Warning: Kernel ABI header at 'tools/include/uapi/linux/mman.h' differs from latest version at 'include/uapi/linux/mman.h'
  diff -u tools/include/uapi/linux/mman.h include/uapi/linux/mman.h

Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-3rvc39lon93kgt5pl31d8g4x@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-10-31 09:57:53 -03:00
Arnaldo Carvalho de Melo
2f967f1dbb perf trace beauty: Use the mmap flags table generated from headers
Instead of requiring us to go on and edit sources to add new flag.

  # perf trace -e *mmap sleep 0.1
     0.025 ( 0.005 ms): sleep/29876 mmap(len: 163746, prot: READ, flags: PRIVATE, fd: 3) = 0x7faa68ad1000
     0.059 ( 0.004 ms): sleep/29876 mmap(len: 8192, prot: READ|WRITE, flags: PRIVATE|ANONYMOUS) = 0x7faa68acf000
     0.069 ( 0.006 ms): sleep/29876 mmap(len: 3889792, prot: EXEC|READ, flags: PRIVATE|DENYWRITE, fd: 3) = 0x7faa6851f000
     0.086 ( 0.009 ms): sleep/29876 mmap(addr: 0x7faa688cb000, len: 24576, prot: READ|WRITE, flags: PRIVATE|FIXED|DENYWRITE, fd: 3, off: 1753088) = 0x7faa688cb000
     0.101 ( 0.005 ms): sleep/29876 mmap(addr: 0x7faa688d1000, len: 14976, prot: READ|WRITE, flags: PRIVATE|FIXED|ANONYMOUS) = 0x7faa688d1000
     0.348 ( 0.005 ms): sleep/29876 mmap(len: 111950656, prot: READ, flags: PRIVATE, fd: 3) = 0x7faa61a5b000
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-ggmoy6vxoygh5yim890ht0kf@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-10-31 09:57:53 -03:00
Arnaldo Carvalho de Melo
fbd7458db7 perf beauty: Wire up the mmap flags table generator to the Makefile
Now when we run 'make -C tools/perf O=/tmp/build/perf' we end up with:

  $ cat /tmp/build/perf/trace/beauty/generated/mmap_flags_array.c
  static const char *mmap_flags[] = {
	[ilog2(0x40) + 1] = "32BIT",
	[ilog2(0x01) + 1] = "SHARED",
	[ilog2(0x02) + 1] = "PRIVATE",
	[ilog2(0x10) + 1] = "FIXED",
	[ilog2(0x20) + 1] = "ANONYMOUS",
	[ilog2(0x100000) + 1] = "FIXED_NOREPLACE",
	[ilog2(0x0100) + 1] = "GROWSDOWN",
	[ilog2(0x0800) + 1] = "DENYWRITE",
	[ilog2(0x1000) + 1] = "EXECUTABLE",
	[ilog2(0x2000) + 1] = "LOCKED",
	[ilog2(0x4000) + 1] = "NORESERVE",
	[ilog2(0x8000) + 1] = "POPULATE",
	[ilog2(0x10000) + 1] = "NONBLOCK",
	[ilog2(0x20000) + 1] = "STACK",
	[ilog2(0x40000) + 1] = "HUGETLB",
	[ilog2(0x80000) + 1] = "SYNC",
  };
  $

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-t3fn7u3tjsupio6e6vkufx9m@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-10-31 09:57:52 -03:00
Arnaldo Carvalho de Melo
80ee5668b8 perf beauty: Add a generator for MAP_ mmap's flag constants
It'll use tools/{arch}/*,include copies of mman.h to generate a table to
be used by tools, initially by the 'mmap' beautifiers in 'perf trace',
but that could also be used to translate from a string constant to the
integer value to be used in a eBPF or tracefs tracepoint filter.

Tested for all archs using:

$ for arch in `ls tools/arch/` ; \
	do echo $arch ; tools/perf/trace/beauty/mmap_flags.sh $arch ; \
   done | less

Example for alpha, an oddball, doesn't include any header, defines all
its stuff:

  $ tools/perf/trace/beauty/mmap_flags.sh alpha
  static const char *mmap_flags[] = {
	[ilog2(0x10) + 1] = "ANONYMOUS",
	[ilog2(0x02000) + 1] = "DENYWRITE",
	[ilog2(0x04000) + 1] = "EXECUTABLE",
	[ilog2(0x100) + 1] = "FIXED",
	[ilog2(0x01000) + 1] = "GROWSDOWN",
	[ilog2(0x100000) + 1] = "HUGETLB",
	[ilog2(0x08000) + 1] = "LOCKED",
	[ilog2(0x40000) + 1] = "NONBLOCK",
	[ilog2(0x10000) + 1] = "NORESERVE",
	[ilog2(0x20000) + 1] = "POPULATE",
	[ilog2(0x02) + 1] = "PRIVATE",
	[ilog2(0x01) + 1] = "SHARED",
	[ilog2(0x80000) + 1] = "STACK",
  };
  $

Common case, my workstation, defines one entry (MAP_32BIT), then
includes mman.h, which gets it to include mman-common.h too:

  $ tools/perf/trace/beauty/mmap_flags.sh
  static const char *mmap_flags[] = {
	[ilog2(0x40) + 1] = "32BIT",
	[ilog2(0x01) + 1] = "SHARED",
	[ilog2(0x02) + 1] = "PRIVATE",
	[ilog2(0x10) + 1] = "FIXED",
	[ilog2(0x20) + 1] = "ANONYMOUS",
	[ilog2(0x100000) + 1] = "FIXED_NOREPLACE",
	[ilog2(0x0100) + 1] = "GROWSDOWN",
	[ilog2(0x0800) + 1] = "DENYWRITE",
	[ilog2(0x1000) + 1] = "EXECUTABLE",
	[ilog2(0x2000) + 1] = "LOCKED",
	[ilog2(0x4000) + 1] = "NORESERVE",
	[ilog2(0x8000) + 1] = "POPULATE",
	[ilog2(0x10000) + 1] = "NONBLOCK",
	[ilog2(0x20000) + 1] = "STACK",
	[ilog2(0x40000) + 1] = "HUGETLB",
	[ilog2(0x80000) + 1] = "SYNC",
  };
  $ uname -m
  x86_64
  $

Sparc, that defines a bunch then includes just mman-common.h:

  $ tools/perf/trace/beauty/mmap_flags.sh sparc
  static const char *mmap_flags[] = {
	[ilog2(0x0800) + 1] = "DENYWRITE",
	[ilog2(0x1000) + 1] = "EXECUTABLE",
	[ilog2(0x0200) + 1] = "GROWSDOWN",
	[ilog2(0x40000) + 1] = "HUGETLB",
	[ilog2(0x100) + 1] = "LOCKED",
	[ilog2(0x10000) + 1] = "NONBLOCK",
	[ilog2(0x40) + 1] = "NORESERVE",
	[ilog2(0x8000) + 1] = "POPULATE",
	[ilog2(0x20000) + 1] = "STACK",
	[ilog2(0x01) + 1] = "SHARED",
	[ilog2(0x02) + 1] = "PRIVATE",
	[ilog2(0x10) + 1] = "FIXED",
	[ilog2(0x20) + 1] = "ANONYMOUS",
	[ilog2(0x100000) + 1] = "FIXED_NOREPLACE",
  };
  [acme@jouet perf]$

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-xydeh491z8fkgglcmqnl5thj@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-10-31 09:57:52 -03:00
Arnaldo Carvalho de Melo
89eb1f3b7f tools include uapi: Update asound.h copy
To silence this perf build warning:

  Warning: Kernel ABI header at 'tools/include/uapi/sound/asound.h' differs from latest version at 'include/uapi/sound/asound.h'
  diff -u tools/include/uapi/sound/asound.h include/uapi/sound/asound.h

Due to this cset:

  a98401518d ("ALSA: timer: fix wrong comment to refer to 'SNDRV_TIMER_PSFLG_*'")

Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Cc: Takashi Iwai <tiwai@suse.de>
Link: https://lkml.kernel.org/n/tip-76gsvs0w2g0x723ivqa2xua3@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-10-31 09:57:52 -03:00
Arnaldo Carvalho de Melo
8dd4c0f68c tools arch uapi: Update asm-generic/unistd.h and arm64 unistd.h copies
To get the changes in:

  82b355d161 ("y2038: Remove newstat family from default syscall set")

Which will make the syscall table used by 'perf trace' for arm64 to be
updated from the changes in that patch.

This silences these perf build warnings:

  Warning: Kernel ABI header at 'tools/arch/arm64/include/uapi/asm/unistd.h' differs from latest version at 'arch/arm64/include/uapi/asm/unistd.h'
  diff -u tools/arch/arm64/include/uapi/asm/unistd.h arch/arm64/include/uapi/asm/unistd.h
  Warning: Kernel ABI header at 'tools/include/uapi/asm-generic/unistd.h' differs from latest version at 'include/uapi/asm-generic/unistd.h'
  diff -u tools/include/uapi/asm-generic/unistd.h include/uapi/asm-generic/unistd.h

Cc: Kim Phillips <kim.phillips@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-3euy7c4yy5mvnp5bm16t9vqg@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-10-31 09:57:51 -03:00
Arnaldo Carvalho de Melo
733ac4f993 tools include uapi: Update linux/fs.h copy
To silence this perf build warning:

  Warning: Kernel ABI header at 'tools/include/uapi/linux/fs.h' differs from latest version at 'include/uapi/linux/fs.h'
  diff -u tools/include/uapi/linux/fs.h include/uapi/linux/fs.h

Due to just two comments added by:

  Fixes: 578bdaabd0 ("crypto: speck - remove Speck")

So nothing that entails changes in tools/, that so far uses fs.h to
generate the mount and umount syscalls 'flags' argument integer->string
tables with:

  $ tools/perf/trace/beauty/mount_flags.sh
  static const char *mount_flags[] = {
	[4096 ? (ilog2(4096) + 1) : 0] = "BIND",
<SNIP>
	[30 + 1] = "ACTIVE",
	[31 + 1] = "NOUSER",
  };
  $
  # trace -e mount,umount mount --bind /proc /mnt
     1.228 ( 2.581 ms): mount/1068 mount(dev_name: /mnt, dir_name: 0x55f011c354a0, type: 0x55f011c38170, flags: BIND) = 0
  # trace -e mount,umount umount /proc /mnt
  umount: /proc: target is busy.
     1.587 ( 0.010 ms): umount/1070 umount2(name: /proc) = -1 EBUSY Device or resource busy
     1.799 (12.660 ms): umount/1070 umount2(name: /mnt) = 0
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Link: https://lkml.kernel.org/n/tip-c00bqzclscgah26z2g5zxm73@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-10-31 09:57:51 -03:00
David S. Miller
e9024d519d perf callchain: Honour the ordering of PERF_CONTEXT_{USER,KERNEL,etc}
When processing using 'perf report -g caller', which is the default, we
ended up reverting the callchain entries received from the kernel, but
simply reverting throws away the information that tells that from a
point onwards the addresses are for userspace, kernel, guest kernel,
guest user, hypervisor.

The idea is that if we are walking backwards, for each cluster of
non-cpumode entries we have to first scan backwards for the next one and
use that for the cluster.

This seems silly and more expensive than it needs to be but it is enough
for a initial fix.

The code here is really complicated because it is intimately intertwined
with the lbr and branch handling, as well as this callchain order,
further fixes will be needed to properly take into account the cpumode
in those cases.

Another problem with ORDER_CALLER is that the NULL "0" IP that is at the
end of most callchains shows up at the top of the histogram because
every callchain contains it and with ORDER_CALLER it is the first entry.

Signed-off-by: David S. Miller <davem@davemloft.net>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Souvik Banerjee <souvik1997@gmail.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: stable@vger.kernel.org # 4.19
Link: https://lkml.kernel.org/n/tip-2wt3ayp6j2y2f2xowixa8y6y@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-10-31 09:57:51 -03:00
Leo Yan
d6c9c05fe1 perf cs-etm: Correct CPU mode for samples
Since commit edeb0c90df ("perf tools: Stop fallbacking to kallsyms for
vdso symbols lookup"), the kernel address cannot be properly parsed to
kernel symbol with command 'perf script -k vmlinux'.  The reason is
CoreSight samples is always to set CPU mode as PERF_RECORD_MISC_USER,
thus it fails to find corresponding map/dso in below flows:

  process_sample_event()
    `-> machine__resolve()
	  `-> thread__find_map(thread, sample->cpumode, sample->ip, al);

In this flow it needs to pass argument 'sample->cpumode' to tell what's
the CPU mode, before it always passed PERF_RECORD_MISC_USER but without
any failure until the commit edeb0c90df ("perf tools: Stop fallbacking
to kallsyms for vdso symbols lookup") has been merged.  The reason is
even with the wrong CPU mode the function thread__find_map() firstly
fails to find map but it will rollback to find kernel map for vdso
symbols lookup.  In the latest code it has removed the fallback code,
thus if CPU mode is PERF_RECORD_MISC_USER then it cannot find map
anymore with kernel address.

This patch is to correct samples CPU mode setting, it creates a new
helper function cs_etm__cpu_mode() to tell what's the CPU mode based on
the address with the info from machine structure; this patch has a bit
extension to check not only kernel and user mode, but also check for
host/guest and hypervisor mode.  Finally this patch uses the function in
instruction and branch samples and also apply in cs_etm__mem_access()
for a minor polishing.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Miller <davem@davemloft.net>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: stable@kernel.org # v4.19
Link: http://lkml.kernel.org/r/1540883908-17018-1-git-send-email-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-10-31 09:57:50 -03:00
Milian Wolff
1fe627da30 perf unwind: Take pgoff into account when reporting elf to libdwfl
libdwfl parses an ELF file itself and creates mappings for the
individual sections. perf on the other hand sees raw mmap events which
represent individual sections. When we encounter an address pointing
into a mapping with pgoff != 0, we must take that into account and
report the file at the non-offset base address.

This fixes unwinding with libdwfl in some cases. E.g. for a file like:

```

using namespace std;

mutex g_mutex;

double worker()
{
    lock_guard<mutex> guard(g_mutex);
    uniform_real_distribution<double> uniform(-1E5, 1E5);
    default_random_engine engine;
    double s = 0;
    for (int i = 0; i < 1000; ++i) {
        s += norm(complex<double>(uniform(engine), uniform(engine)));
    }
    cout << s << endl;
    return s;
}

int main()
{
    vector<std::future<double>> results;
    for (int i = 0; i < 10000; ++i) {
        results.push_back(async(launch::async, worker));
    }
    return 0;
}
```

Compile it with `g++ -g -O2 -lpthread cpp-locking.cpp  -o cpp-locking`,
then record it with `perf record --call-graph dwarf -e
sched:sched_switch`.

When you analyze it with `perf script` and libunwind, you should see:

```
cpp-locking 20038 [005] 54830.236589: sched:sched_switch: prev_comm=cpp-locking prev_pid=20038 prev_prio=120 prev_state=T ==> next_comm=swapper/5 next_pid=0 next_prio=120
        ffffffffb166fec5 __sched_text_start+0x545 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb166fec5 __sched_text_start+0x545 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1670208 schedule+0x28 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb16737cc rwsem_down_read_failed+0xec (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1665e04 call_rwsem_down_read_failed+0x14 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1672a03 down_read+0x13 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb106bd85 __do_page_fault+0x445 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb18015f5 page_fault+0x45 (/lib/modules/4.14.78-1-lts/build/vmlinux)
            7f38e4252591 new_heap+0x101 (/usr/lib/libc-2.28.so)
            7f38e4252d0b arena_get2.part.4+0x2fb (/usr/lib/libc-2.28.so)
            7f38e4255b1c tcache_init.part.6+0xec (/usr/lib/libc-2.28.so)
            7f38e42569e5 __GI___libc_malloc+0x115 (inlined)
            7f38e4241790 __GI__IO_file_doallocate+0x90 (inlined)
            7f38e424fbbf __GI__IO_doallocbuf+0x4f (inlined)
            7f38e424ee47 __GI__IO_file_overflow+0x197 (inlined)
            7f38e424df36 _IO_new_file_xsputn+0x116 (inlined)
            7f38e4242bfb __GI__IO_fwrite+0xdb (inlined)
            7f38e463fa6d std::basic_streambuf<char, std::char_traits<char> >::sputn(char const*, long)+0x1cd (inlined)
            7f38e463fa6d std::ostreambuf_iterator<char, std::char_traits<char> >::_M_put(char const*, long)+0x1cd (inlined)
            7f38e463fa6d std::ostreambuf_iterator<char, std::char_traits<char> > std::__write<char>(std::ostreambuf_iterator<char, std::char_traits<char> >, char const*, int)+0x1cd (inlined)
            7f38e463fa6d std::ostreambuf_iterator<char, std::char_traits<char> > std::num_put<char, std::ostreambuf_iterator<char, std::char_traits<char> > >::_M_insert_float<double>(std::ostreambuf_iterator<c>
            7f38e464bd70 std::num_put<char, std::ostreambuf_iterator<char, std::char_traits<char> > >::put(std::ostreambuf_iterator<char, std::char_traits<char> >, std::ios_base&, char, double) const+0x90 (inl>
            7f38e464bd70 std::ostream& std::ostream::_M_insert<double>(double)+0x90 (/usr/lib/libstdc++.so.6.0.25)
            563b9cb502f7 std::ostream::operator<<(double)+0xb7 (inlined)
            563b9cb502f7 worker()+0xb7 (/ssd/milian/projects/kdab/rnd/hotspot/build/tests/test-clients/cpp-locking/cpp-locking)
            563b9cb506fb double std::__invoke_impl<double, double (*)()>(std::__invoke_other, double (*&&)())+0x2b (inlined)
            563b9cb506fb std::__invoke_result<double (*)()>::type std::__invoke<double (*)()>(double (*&&)())+0x2b (inlined)
            563b9cb506fb decltype (__invoke((_S_declval<0ul>)())) std:🧵:_Invoker<std::tuple<double (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>)+0x2b (inlined)
            563b9cb506fb std:🧵:_Invoker<std::tuple<double (*)()> >::operator()()+0x2b (inlined)
            563b9cb506fb std::__future_base::_Task_setter<std::unique_ptr<std::__future_base::_Result<double>, std::__future_base::_Result_base::_Deleter>, std:🧵:_Invoker<std::tuple<double (*)()> >, dou>
            563b9cb506fb std::_Function_handler<std::unique_ptr<std::__future_base::_Result_base, std::__future_base::_Result_base::_Deleter> (), std::__future_base::_Task_setter<std::unique_ptr<std::__future_>
            563b9cb507e8 std::function<std::unique_ptr<std::__future_base::_Result_base, std::__future_base::_Result_base::_Deleter> ()>::operator()() const+0x28 (inlined)
            563b9cb507e8 std::__future_base::_State_baseV2::_M_do_set(std::function<std::unique_ptr<std::__future_base::_Result_base, std::__future_base::_Result_base::_Deleter> ()>*, bool*)+0x28 (/ssd/milian/>
            7f38e46d24fe __pthread_once_slow+0xbe (/usr/lib/libpthread-2.28.so)
            563b9cb51149 __gthread_once+0xe9 (inlined)
            563b9cb51149 void std::call_once<void (std::__future_base::_State_baseV2::*)(std::function<std::unique_ptr<std::__future_base::_Result_base, std::__future_base::_Result_base::_Deleter> ()>*, bool*)>
            563b9cb51149 std::__future_base::_State_baseV2::_M_set_result(std::function<std::unique_ptr<std::__future_base::_Result_base, std::__future_base::_Result_base::_Deleter> ()>, bool)+0xe9 (inlined)
            563b9cb51149 std::__future_base::_Async_state_impl<std:🧵:_Invoker<std::tuple<double (*)()> >, double>::_Async_state_impl(std:🧵:_Invoker<std::tuple<double (*)()> >&&)::{lambda()#1}::op>
            563b9cb51149 void std::__invoke_impl<void, std::__future_base::_Async_state_impl<std:🧵:_Invoker<std::tuple<double (*)()> >, double>::_Async_state_impl(std:🧵:_Invoker<std::tuple<double>
            563b9cb51149 std::__invoke_result<std::__future_base::_Async_state_impl<std:🧵:_Invoker<std::tuple<double (*)()> >, double>::_Async_state_impl(std:🧵:_Invoker<std::tuple<double (*)()> >>
            563b9cb51149 decltype (__invoke((_S_declval<0ul>)())) std:🧵:_Invoker<std::tuple<std::__future_base::_Async_state_impl<std:🧵:_Invoker<std::tuple<double (*)()> >, double>::_Async_state_>
            563b9cb51149 std:🧵:_Invoker<std::tuple<std::__future_base::_Async_state_impl<std:🧵:_Invoker<std::tuple<double (*)()> >, double>::_Async_state_impl(std:🧵:_Invoker<std::tuple<dou>
            563b9cb51149 std:🧵:_State_impl<std:🧵:_Invoker<std::tuple<std::__future_base::_Async_state_impl<std:🧵:_Invoker<std::tuple<double (*)()> >, double>::_Async_state_impl(std::thread>
            7f38e45f0062 execute_native_thread_routine+0x12 (/usr/lib/libstdc++.so.6.0.25)
            7f38e46caa9c start_thread+0xfc (/usr/lib/libpthread-2.28.so)
            7f38e42ccb22 __GI___clone+0x42 (inlined)
```

Before this patch, using libdwfl, you would see:

```
cpp-locking 20038 [005] 54830.236589: sched:sched_switch: prev_comm=cpp-locking prev_pid=20038 prev_prio=120 prev_state=T ==> next_comm=swapper/5 next_pid=0 next_prio=120
        ffffffffb166fec5 __sched_text_start+0x545 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb166fec5 __sched_text_start+0x545 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1670208 schedule+0x28 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb16737cc rwsem_down_read_failed+0xec (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1665e04 call_rwsem_down_read_failed+0x14 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1672a03 down_read+0x13 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb106bd85 __do_page_fault+0x445 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb18015f5 page_fault+0x45 (/lib/modules/4.14.78-1-lts/build/vmlinux)
            7f38e4252591 new_heap+0x101 (/usr/lib/libc-2.28.so)
        a041161e77950c5c [unknown] ([unknown])
```

With this patch applied, we get a bit further in unwinding:

```
cpp-locking 20038 [005] 54830.236589: sched:sched_switch: prev_comm=cpp-locking prev_pid=20038 prev_prio=120 prev_state=T ==> next_comm=swapper/5 next_pid=0 next_prio=120
        ffffffffb166fec5 __sched_text_start+0x545 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb166fec5 __sched_text_start+0x545 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1670208 schedule+0x28 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb16737cc rwsem_down_read_failed+0xec (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1665e04 call_rwsem_down_read_failed+0x14 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1672a03 down_read+0x13 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb106bd85 __do_page_fault+0x445 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb18015f5 page_fault+0x45 (/lib/modules/4.14.78-1-lts/build/vmlinux)
            7f38e4252591 new_heap+0x101 (/usr/lib/libc-2.28.so)
            7f38e4252d0b arena_get2.part.4+0x2fb (/usr/lib/libc-2.28.so)
            7f38e4255b1c tcache_init.part.6+0xec (/usr/lib/libc-2.28.so)
            7f38e42569e5 __GI___libc_malloc+0x115 (inlined)
            7f38e4241790 __GI__IO_file_doallocate+0x90 (inlined)
            7f38e424fbbf __GI__IO_doallocbuf+0x4f (inlined)
            7f38e424ee47 __GI__IO_file_overflow+0x197 (inlined)
            7f38e424df36 _IO_new_file_xsputn+0x116 (inlined)
            7f38e4242bfb __GI__IO_fwrite+0xdb (inlined)
            7f38e463fa6d std::basic_streambuf<char, std::char_traits<char> >::sputn(char const*, long)+0x1cd (inlined)
            7f38e463fa6d std::ostreambuf_iterator<char, std::char_traits<char> >::_M_put(char const*, long)+0x1cd (inlined)
            7f38e463fa6d std::ostreambuf_iterator<char, std::char_traits<char> > std::__write<char>(std::ostreambuf_iterator<char, std::char_traits<char> >, char const*, int)+0x1cd (inlined)
            7f38e463fa6d std::ostreambuf_iterator<char, std::char_traits<char> > std::num_put<char, std::ostreambuf_iterator<char, std::char_traits<char> > >::_M_insert_float<double>(std::ostreambuf_iterator<c>
            7f38e464bd70 std::num_put<char, std::ostreambuf_iterator<char, std::char_traits<char> > >::put(std::ostreambuf_iterator<char, std::char_traits<char> >, std::ios_base&, char, double) const+0x90 (inl>
            7f38e464bd70 std::ostream& std::ostream::_M_insert<double>(double)+0x90 (/usr/lib/libstdc++.so.6.0.25)
            563b9cb502f7 std::ostream::operator<<(double)+0xb7 (inlined)
            563b9cb502f7 worker()+0xb7 (/ssd/milian/projects/kdab/rnd/hotspot/build/tests/test-clients/cpp-locking/cpp-locking)
        6eab825c1ee3e4ff [unknown] ([unknown])
```

Note that the backtrace is still stopping too early, when compared to
the nice results obtained via libunwind. It's unclear so far what the
reason for that is.

Committer note:

Further comment by Milian on the thread started on the Link: tag below:

 ---
The remaining issue is due to a bug in elfutils:

https://sourceware.org/ml/elfutils-devel/2018-q4/msg00089.html

With both patches applied, libunwind and elfutils produce the same output for
the above scenario.
 ---

Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20181029141644.3907-1-milian.wolff@kdab.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-10-31 09:57:50 -03:00
Arnaldo Carvalho de Melo
218d61110f perf top: Do not use overwrite mode by default
Enabling --overwrite mode allows us to to use just the most recent
records, which helps in high core count machines such as Knights
Landing/Mill, but right now is being disabled by default as the pausing
used in this technique is leading to loss of metadata events such as
PERF_RECORD_MMAP which makes 'perf top' unable to resolve samples,
leading to lots of unknown samples appearing on the UI.

Enabling this may be useful if you are in such machines and profiling a
workload that doesn't creates short lived threads and/or doesn't uses
many executable mmap operations.

Work is being planed to solve this situation, till then, this will
remain disabled by default.

Reported-by: David Miller <davem@davemloft.net>
Acked-by: Kan Liang <kan.liang@intel.com>
Link: https://lkml.kernel.org/r/4f84468f-37d9-cf1b-12c1-514ef74b6a48@linux.intel.com
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: ebebbf0823 ("perf top: Switch default mode to overwrite mode")
Link: https://lkml.kernel.org/n/tip-ehvf77vi1si9409r7p4wx788@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-10-31 09:57:31 -03:00
Michael Ellerman
69f8117f17 selftests/powerpc/cache_shape: Fix out-of-tree build
Use TEST_GEN_PROGS and don't redefine all, this makes the out-of-tree
build work. We need to move the extra dependencies below the include
of lib.mk, because it adds the $(OUTPUT) prefix if it's defined.

We can also drop the clean rule, lib.mk does it for us.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-31 23:56:22 +11:00
Michael Ellerman
266bac361d selftests/powerpc/switch_endian: Fix out-of-tree build
For the out-of-tree build to work we need to tell switch_endian_test
to look for check-reversed.S in $(OUTPUT).

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-31 23:56:21 +11:00
Joel Stanley
98415da03a selftests/powerpc/pmu: Link ebb tests with -no-pie
When running the ebb tests after building on a ppc64le Ubuntu machine:

 $ pmu/ebb/reg_access_test: error while loading shared libraries:
 R_PPC64_ADDR16_HI reloc at 0x000000013a965130 for symbol `' out of
 range

This is because the Ubuntu toolchain builds has PIE enabled by default.
Change it to be always off instead.

Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-31 23:56:21 +11:00
Joel Stanley
27825349d7 selftests/powerpc/signal: Fix out-of-tree build
We should use TEST_GEN_PROGS, not TEST_PROGS. That tells the selftests
makefile (lib.mk) that those tests are generated (built), and so it
adds the $(OUTPUT) prefix for us, making the out-of-tree build work
correctly.

It also means we don't need our own clean rule, lib.mk does it.

We also have to update the signal_tm rule to use $(OUTPUT).

Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-31 23:56:20 +11:00
Joel Stanley
c39b79082a selftests/powerpc/ptrace: Fix out-of-tree build
We should use TEST_GEN_PROGS, not TEST_PROGS. That tells the selftests
makefile (lib.mk) that those tests are generated (built), and so it
adds the $(OUTPUT) prefix for us, making the out-of-tree build work
correctly.

It also means we don't need our own clean rule, lib.mk does it.

We also have to update the ptrace-pkey and core-pkey rules to use
$(OUTPUT).

Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-31 23:56:19 +11:00
Joel Stanley
a0aebae07f selftests: powerpc: Fix warning for security subdir
typing 'make' inside tools/testing/selftests/powerpc gave a build
warning:

BUILD_TARGET=tools/testing/selftests/powerpc/security; mkdir -p $BUILD_TARGET; make OUTPUT=$BUILD_TARGET -k -C security all
make[1]: Entering directory 'tools/testing/selftests/powerpc/security'
../../lib.mk:20: ../../../../scripts/subarch.include: No such file or directory
make[1]: *** No rule to make target '../../../../scripts/subarch.include'.
make[1]: Failed to remake makefile '../../../../scripts/subarch.include'.

The build is one level deeper than lib.mk thinks it is. Set top_srcdir
to set things straight.

Note that the test program is still built.

Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-31 14:36:33 +11:00
Yonghong Song
b31d30d9be tools/bpf: add unlimited rlimit for flow_dissector_load
On our test machine, bpf selftest test_flow_dissector.sh failed
with the following error:
  # ./test_flow_dissector.sh
  bpffs not mounted. Mounting...
  libbpf: failed to create map (name: 'jmp_table'): Operation not permitted
  libbpf: failed to load object 'bpf_flow.o'
  ./flow_dissector_load: bpf_prog_load bpf_flow.o
  selftests: test_flow_dissector [FAILED]

Let us increase the rlimit to remove the above map
creation failure.

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-30 23:31:21 +01:00
Linus Torvalds
343a9f3540 The biggest change here is the updates to kprobes
Back in January I posted patches to create function based events. These were
 the events that you suggested I make to allow developers to easily create
 events in code where no trace event exists. After posting those changes for
 review, it was suggested that we implement this instead with kprobes.
 
 The problem with kprobes is that the interface is too complex and needs to
 be simplified. Masami Hiramatsu posted patches in March and I've been
 playing with them a bit. There's been a bit of clean up in the kprobe code
 that was inspired by the function based event patches, and a couple of
 enhancements to the kprobe event interface.
 
  - If the arch supports it (we added support for x86), you can place a
    kprobe event at the start of a function and use $arg1, $arg2, etc
    to reference the arguments of a function. (Before you needed to know
    what register or where on the stack the argument was).
 
  - The second is a way to see array of events. For example, if you reference
    a mac address, you can add:
 
    echo 'p:mac ip_rcv perm_addr=+574($arg2):x8[6]' > kprobe_events
 
    And this will produce:
 
    mac: (ip_rcv+0x0/0x140) perm_addr={0x52,0x54,0x0,0xc0,0x76,0xec}
 
 Other changes include
 
  - Exporting trace_dump_stack to modules
 
  - Have the stack tracer trace the entire stack (stop trying to remove
    tracing itself, as we keep removing too much).
 
  - Added support for SDT in uprobes
 -----BEGIN PGP SIGNATURE-----
 
 iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCW9hdjxQccm9zdGVkdEBn
 b29kbWlzLm9yZwAKCRAp5XQQmuv6qmtbAP9GS/o2WSvsYLSIw4+mF94eCL06lUxp
 rRrktkEofm/PagEAl2JNmvHrAJN+LIrajqXTbwlZ7Ckk1rZhCW41Am7qnQs=
 =sTUM
 -----END PGP SIGNATURE-----

Merge tag 'trace-v4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "The biggest change here is the updates to kprobes

  Back in January I posted patches to create function based events.
  These were the events that you suggested I make to allow developers to
  easily create events in code where no trace event exists. After
  posting those changes for review, it was suggested that we implement
  this instead with kprobes.

  The problem with kprobes is that the interface is too complex and
  needs to be simplified. Masami Hiramatsu posted patches in March and
  I've been playing with them a bit. There's been a bit of clean up in
  the kprobe code that was inspired by the function based event patches,
  and a couple of enhancements to the kprobe event interface.

   - If the arch supports it (we added support for x86), you can place a
     kprobe event at the start of a function and use $arg1, $arg2, etc
     to reference the arguments of a function. (Before you needed to
     know what register or where on the stack the argument was).

   - The second is a way to see array of events. For example, if you
     reference a mac address, you can add:

	echo 'p:mac ip_rcv perm_addr=+574($arg2):x8[6]' > kprobe_events

     And this will produce:

	mac: (ip_rcv+0x0/0x140) perm_addr={0x52,0x54,0x0,0xc0,0x76,0xec}

  Other changes include

   - Exporting trace_dump_stack to modules

   - Have the stack tracer trace the entire stack (stop trying to remove
     tracing itself, as we keep removing too much).

   - Added support for SDT in uprobes"

[ SDT - "Statically Defined Tracing" are userspace markers for tracing.
  Let's not use random TLA's in explanations unless they are fairly
  well-established as generic (at least for kernel people) - Linus ]

* tag 'trace-v4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (24 commits)
  tracing: Have stack tracer trace full stack
  tracing: Export trace_dump_stack to modules
  tracing: probeevent: Fix uninitialized used of offset in parse args
  tracing/kprobes: Allow kprobe-events to record module symbol
  tracing/kprobes: Check the probe on unloaded module correctly
  tracing/uprobes: Fix to return -EFAULT if copy_from_user failed
  tracing: probeevent: Add $argN for accessing function args
  x86: ptrace: Add function argument access API
  tracing: probeevent: Add array type support
  tracing: probeevent: Add symbol type
  tracing: probeevent: Unify fetch_insn processing common part
  tracing: probeevent: Append traceprobe_ for exported function
  tracing: probeevent: Return consumed bytes of dynamic area
  tracing: probeevent: Unify fetch type tables
  tracing: probeevent: Introduce new argument fetching code
  tracing: probeevent: Remove NOKPROBE_SYMBOL from print functions
  tracing: probeevent: Cleanup argument field definition
  tracing: probeevent: Cleanup print argument functions
  trace_uprobe: support reference counter in fd-based uprobe
  perf probe: Support SDT markers having reference counter (semaphore)
  ...
2018-10-30 09:49:56 -07:00
Linus Torvalds
f4267b3604 Masami had a couple more fixes to the synthetic events. One was a proper
error return value, and the other is for the self tests.
 -----BEGIN PGP SIGNATURE-----
 
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 j6eaqRXu0JDfsQD7Bb19KxSHUEaPSpZIo68N5OJkoTv9UxD2KYuRysu4VQ8=
 =y1Gc
 -----END PGP SIGNATURE-----

Merge tag 'trace-v4.19-rc8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Masami had a couple more fixes to the synthetic events. One was a
  proper error return value, and the other is for the self tests"

* tag 'trace-v4.19-rc8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  selftests/ftrace: Fix synthetic event test to delete event correctly
  tracing: Return -ENOENT if there is no target synthetic event
2018-10-30 09:47:28 -07:00
Arnaldo Carvalho de Melo
4e303fbe2d perf top: Allow disabling the overwrite mode
In ebebbf0823 ("perf top: Switch default mode to overwrite mode") we
forgot to leave a way to disable that new default, add a --overwrite
option that can be disabled using --no-overwrite, since the code already
in such a way that we can readily disable this mode.

This is useful when investigating bugs with this mode like the recent
report from David Miller where lots of unknown symbols appear due to
disabling the events while processing them which disables all record
types, not just PERF_RECORD_SAMPLE, which makes it impossible to resolve
maps when we lose PERF_RECORD_MMAP records.

This can be easily seen while building a kernel, when there are lots of
short lived processes.

Reported-by: David Miller <davem@davemloft.net>
Acked-by: Kan Liang <kan.liang@intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: ebebbf0823 ("perf top: Switch default mode to overwrite mode")
Link: https://lkml.kernel.org/n/tip-oqgsz2bq4kgrnnajrafcdhie@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-10-30 11:46:23 -03:00
Arnaldo Carvalho de Melo
23c07a23cb perf trace: Beautify mount's first pathname arg
The pathname beautifiers so far support just one augmented pathname per
syscall, so do it just for mount's first arg, later this will get fixed.

With:

  # perf probe -l
  probe:vfs_getname    (on getname_flags:73@acme/git/linux/fs/namei.c with pathname)
  #

Later this will get added to augmented_syscalls.c (eBPF):

In one xterm:

  # perf trace -e mount,umount
  2687.331 ( 3.544 ms): mount/8892 mount(dev_name: /mnt, dir_name: 0x561f9ac184a0, type: 0x561f9ac1b170, flags: BIND) = 0
  3912.126 ( 8.807 ms): umount/8895 umount2(name: /mnt) = 0
  ^C#

In the other:

  $ sudo mount --bind /proc /mnt
  $ sudo umount /mnt

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Benjamin Peterson <benjamin@python.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-qsvhrm2es635cl4zicqjeth2@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-10-30 11:46:23 -03:00