For better performance analysis of dynamically JITed and loaded kernel
functions, such as BPF programs, this patch introduces
PERF_RECORD_KSYMBOL, a new perf_event_type that exposes kernel symbol
register/unregister information to user space.

The following data structure is used for PERF_RECORD_KSYMBOL.

    /*
     * struct {
     *      struct perf_event_header        header;
     *      u64                             addr;
     *      u32                             len;
     *      u16                             ksym_type;
     *      u16                             flags;
     *      char                            name[];
     *      struct sample_id                sample_id;
     * };
     */
Signed-off-by: NSong Liu <songliubraving@fb.com>
Reviewed-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kernel-team@fb.com
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/20190117161521.1341602-2-songliubraving@fb.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

For the original mode of operation it isn't needed, since we report back
errors via PERF_RECORD_LOST records in the ring buffer, but for use in
bpf_perf_event_output() it is convenient to return the errors, basically
-ENOSPC.

Currently bpf_perf_event_output() returns an error indication, the last
thing it does, which is to push it to the ring buffer is that can fail
and if so, this failure won't be reported back to its users, fix it.
Reported-by: NJamal Hadi Salim <jhs@mojatatu.com>
Tested-by: NJamal Hadi Salim <jhs@mojatatu.com>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/r/20190118150938.GN5823@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add support for the new s390 PMU device cpum_cf_diag to extract the
counter set diagnostic data. This data is available as event raw data
and can be created with this command:

  [root@s35lp76 perf]# ./perf record -R -e '{rbd000,rbc000}' --
                                 ~/mytests/facultaet 2500
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.009 MB perf.data ]
  [root@s35lp76 perf]#

The new event 0xbc000 generated this counter set diagnostic trace data.
The data can be extracted using command:

  [root@s35lp76 perf]# ./perf report --stdio --itrace=d
  #
  # Total Lost Samples: 0
  #
  # Samples: 21  of events 'anon group { rbd000, rbc000 }'
  # Event count (approx.): 21
  #
  #         Overhead  Command    Shared Object      Symbol
  # ................  .........  .................  ........................
  #
    80.95%   0.00%  facultaet  facultaet          [.] facultaet
     4.76%   0.00%  facultaet  [kernel.kallsyms]  [k] check_chain_key
     4.76%   0.00%  facultaet  [kernel.kallsyms]  [k] ftrace_likely_update
     4.76%   0.00%  facultaet  [kernel.kallsyms]  [k] lock_release
     4.76%   0.00%  facultaet  libc-2.26.so       [.] _dl_addr
  [root@s35lp76 perf]# ll aux*
  -rw-r--r-- 1 root root 3408 Oct 16 12:40 aux.ctr.02
  -rw-r--r-- 1 root root 4096 Oct 16 12:40 aux.smp.02
  [root@s35lp76 perf]#

The files named aux.ctr.## contain the counter set diagnostic data and
the files named aux.smp.## contain the sampling diagnostic data. ##
stand for the CPU number the data was taken from.
Signed-off-by: NThomas Richter <tmricht@linux.ibm.com>
Reviewed-by: NHendrik Brueckner <brueckner@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Link: http://lkml.kernel.org/r/20190117093003.96287-4-tmricht@linux.ibm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

On s390 the CPU Measurement Facility diagnostic counter sets are
displayed by counter number and value. Add the logical counter name in
the output (if it is available). Otherwise "unknown" is shown.

Output before:

 [root@s35lp76 perf]# ./perf report -D --stdio
 [00000000] Counterset:0 Counters:6
   Counter:000 Value:0x000000000085ec36 Counter:001 Value:0x0000000000796c94
   Counter:002 Value:0x0000000000005ada Counter:003 Value:0x0000000000092460
   Counter:004 Value:0x0000000000006073 Counter:005 Value:0x00000000001a9a73
 [0x000038] Counterset:1 Counters:2
   Counter:000 Value:0x000000000007c59f Counter:001 Value:0x000000000002fad6
 [0x000050] Counterset:2 Counters:16
   Counter:000 Value:000000000000000000 Counter:001 Value:000000000000000000

Output after:

    [root@s35lp76 perf]# ./perf report -D --stdio

 [00000000] Counterset:0 Counters:6
     Counter:000 cpu_cycles Value:0x000000000085ec36
     Counter:001 instructions Value:0x0000000000796c94
     Counter:002 l1i_dir_writes Value:0x0000000000005ada
     Counter:003 l1i_penalty_cycles Value:0x0000000000092460
     Counter:004 l1d_dir_writes Value:0x0000000000006073
     Counter:005 l1d_penalty_cycles Value:0x00000000001a9a73
 [0x000038] Counterset:1 Counters:2
     Counter:000 problem_state_cpu_cycles Value:0x000000000007c59f
     Counter:001 problem_state_instructions Value:0x000000000002fad6
 [0x000050] Counterset:2 Counters:16
     Counter:000 prng_functions Value:000000000000000000
Signed-off-by: NThomas Richter <tmricht@linux.ibm.com>
Reviewed-by: NHendrik Brueckner <brueckner@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Link: http://lkml.kernel.org/r/20190117093003.96287-3-tmricht@linux.ibm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

On s390 the event bc000 (also named CF_DIAG) extracts the CPU
Measurement Facility diagnostic counter sets and displays them as
counter number and counter value pairs sorted by counter set number.

Output:
 [root@s35lp76 perf]# ./perf report -D --stdio

 [00000000] Counterset:0 Counters:6
   Counter:000 Value:0x000000000085ec36 Counter:001 Value:0x0000000000796c94
   Counter:002 Value:0x0000000000005ada Counter:003 Value:0x0000000000092460
   Counter:004 Value:0x0000000000006073 Counter:005 Value:0x00000000001a9a73
 [0x000038] Counterset:1 Counters:2
   Counter:000 Value:0x000000000007c59f Counter:001 Value:0x000000000002fad6
 [0x000050] Counterset:2 Counters:16
   Counter:000 Value:000000000000000000 Counter:001 Value:000000000000000000
   Counter:002 Value:000000000000000000 Counter:003 Value:000000000000000000
   Counter:004 Value:000000000000000000 Counter:005 Value:000000000000000000
   Counter:006 Value:000000000000000000 Counter:007 Value:000000000000000000
   Counter:008 Value:000000000000000000 Counter:009 Value:000000000000000000
   Counter:010 Value:000000000000000000 Counter:011 Value:000000000000000000
   Counter:012 Value:000000000000000000 Counter:013 Value:000000000000000000
   Counter:014 Value:000000000000000000 Counter:015 Value:000000000000000000
 [0x0000d8] Counterset:3 Counters:128
   Counter:000 Value:0x000000000000020f Counter:001 Value:0x00000000000001d8
   Counter:002 Value:0x000000000000d7fa Counter:003 Value:0x000000000000008b
   ...

The number in brackets is the offset into the raw data field of the
sample.

New functions trace_event_sample_raw__init() and s390_sample_raw() are
introduced in the code path to enable interpretation on non s390
platforms. This event bc000 attached raw data is generated only on s390
platform. Correct display on other platforms requires correct endianness
handling.

Committer notes:

Added a init function that sets up a evlist function pointer to avoid
repeated tests on evlist->env and calls to perf_env__name() that
involves normalizing, etc, for each PERF_RECORD_SAMPLE.

Removed needless __maybe_unused from the trace_event_raw()
prototype in session.h, move it to be an static function in evlist.

The 'offset' variable is a size_t, not an u64, fix it to avoid this on
some arches:

    CC       /tmp/build/perf/util/s390-sample-raw.o
  util/s390-sample-raw.c: In function 's390_cpumcfdg_testctr':
  util/s390-sample-raw.c:77:4: error: format '%llx' expects argument of type 'long long unsigned int', but argument 4 has type 'size_t' [-Werror=format=]
      pr_err("Invalid counter set entry at %#"  PRIx64 "\n",
      ^
  cc1: all warnings being treated as errors
Signed-off-by: NThomas Richter <tmricht@linux.ibm.com>
Reviewed-by: NHendrik Brueckner <brueckner@linux.ibm.com>
Link: https://lkml.kernel.org/r/9c856ac0-ef23-72b5-901d-a1f815508976@linux.ibm.com
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Link: https://lkml.kernel.org/n/tip-s3jhif06et9ug78qhclw41z1@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Remove duplicate headers which are included more than once in the same
file.
Signed-off-by: NBrajeswar Ghosh <brajeswar.linux@gmail.com>
Acked-by: NSouptick Joarder <jrdr.linux@gmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Colin King <colin.king@canonical.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sabyasachi Gupta <sabyasachi.linux@gmail.com>
Link: http://lkml.kernel.org/r/20190115135916.GA3629@hp-pavilion-15-notebook-pc-brajeswarSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

It is already included a little bit higher up in that file.
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190117072504.14428-1-yuehaibing@huawei.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The reader object is defined by file's fd, data offset and data size.

Now we can simply define a reader object for an arbitrary file data
portion and pass it to reader__process_events().
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Acked-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190110101301.6196-7-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add 'data_offset' member to reader object.
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Acked-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190110101301.6196-6-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add a  'data_size' member to the reader object. Keep the 'data_size'
variable instead of replacing it with rd.data_size as it will be used in
the following patch.
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Acked-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190110101301.6196-5-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add a session private reader object to encapsulate the reading of the
event data block. Starting with a 'fd' field.
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Acked-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190110101301.6196-4-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

It's not needed and removing it makes the code a little simpler for the
upcoming changes.

It's safe to replace file_size with data_size, because the
perf_data__size() value is never smaller than data_offset + data_size.
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Acked-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190110101301.6196-3-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To reduce function arguments and the code.
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Acked-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190110101301.6196-2-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

An automatic const char[] variable gets initialized at runtime, just
like any other automatic variable. For long strings, that uses a lot of
stack and wastes time building the string; e.g. for the "No %s
allocation events..." case one has:

  444516:       48 b8 4e 6f 20 25 73 20 61 6c   movabs $0x6c61207325206f4e,%rax # "No %s al"
  ...
  444674:       48 89 45 80                     mov    %rax,-0x80(%rbp)
  444678:       48 b8 6c 6f 63 61 74 69 6f 6e   movabs $0x6e6f697461636f6c,%rax # "location"
  444682:       48 89 45 88                     mov    %rax,-0x78(%rbp)
  444686:       48 b8 20 65 76 65 6e 74 73 20   movabs $0x2073746e65766520,%rax # " events "
  444690:       66 44 89 55 c4                  mov    %r10w,-0x3c(%rbp)
  444695:       48 89 45 90                     mov    %rax,-0x70(%rbp)
  444699:       48 b8 66 6f 75 6e 64 2e 20 20   movabs $0x20202e646e756f66,%rax

Make them all static so that the compiler just references objects in .rodata.

Committer testing:

Ok, using dwarves's codiff tool:

    $ codiff --functions /tmp/perf.before ~/bin/perf
  builtin-sched.c:
    cmd_sched                 |  -48
   1 function changed, 48 bytes removed, diff: -48

  builtin-report.c:
    cmd_report                |  -32
   1 function changed, 32 bytes removed, diff: -32

  builtin-kmem.c:
    cmd_kmem                  |  -64
    build_alloc_func_list     |  -50
   2 functions changed, 114 bytes removed, diff: -114

  builtin-c2c.c:
    perf_c2c__report          | -390
   1 function changed, 390 bytes removed, diff: -390

  ui/browsers/header.c:
    tui__header_window        | -104
   1 function changed, 104 bytes removed, diff: -104

  /home/acme/bin/perf:
   9 functions changed, 688 bytes removed, diff: -688
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20181102230624.20064-1-linux@rasmusvillemoes.dkSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Now that perf_flags is not used we remove it.
Signed-off-by: NAndrew Murray <andrew.murray@arm.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: robin.murphy@arm.com
Cc: suzuki.poulose@arm.com
Link: https://lkml.kernel.org/r/1547128414-50693-13-git-send-email-andrew.murray@arm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

For x86 PMUs that do not support context exclusion let's advertise the
PERF_PMU_CAP_NO_EXCLUDE capability. This ensures that perf will
prevent us from handling events where any exclusion flags are set.
Let's also remove the now unnecessary check for exclusion flags.

This change means that amd/iommu and amd/uncore will now also
indicate that they do not support exclude_{hv|idle} and intel/uncore
that it does not support exclude_{guest|host}.
Signed-off-by: NAndrew Murray <andrew.murray@arm.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: robin.murphy@arm.com
Cc: suzuki.poulose@arm.com
Link: https://lkml.kernel.org/r/1547128414-50693-12-git-send-email-andrew.murray@arm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

For drivers that do not support context exclusion let's advertise the
PERF_PMU_CAP_NOEXCLUDE capability. This ensures that perf will
prevent us from handling events where any exclusion flags are set.
Let's also remove the now unnecessary check for exclusion flags.

PMU drivers that support at least one exclude flag won't have the
PERF_PMU_CAP_NOEXCLUDE capability set - these PMU drivers should still
check and fail on unsupported exclude flags. These missing tests are
not added in this patch.
Signed-off-by: NAndrew Murray <andrew.murray@arm.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: robin.murphy@arm.com
Cc: suzuki.poulose@arm.com
Link: https://lkml.kernel.org/r/1547128414-50693-11-git-send-email-andrew.murray@arm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

For PowerPC PMUs that do not support context exclusion let's
advertise the PERF_PMU_CAP_NO_EXCLUDE capability. This ensures that
perf will prevent us from handling events where any exclusion flags
are set. Let's also remove the now unnecessary check for exclusion
flags.
Signed-off-by: NAndrew Murray <andrew.murray@arm.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: NMadhavan Srinivasan <maddy@linux.vnet.ibm.com>
Acked-by: NMichael Ellerman <mpe@ellerman.id.au>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: robin.murphy@arm.com
Cc: suzuki.poulose@arm.com
Link: https://lkml.kernel.org/r/1547128414-50693-10-git-send-email-andrew.murray@arm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

For drivers that do not support context exclusion let's advertise the
PERF_PMU_CAP_NO_EXCLUDE capability. This ensures that perf will
prevent us from handling events where any exclusion flags are set.
Let's also remove the now unnecessary check for exclusion flags.

This change means that qcom_{l2|l3}_pmu will now also indicate that
they do not support exclude_{host|guest} and that xgene_pmu does
not also support exclude_idle and exclude_hv.

Note that for qcom_l2_pmu we now implictly return -EINVAL instead
of -EOPNOTSUPP. This change will result in the perf userspace
utility retrying the perf_event_open system call with fallback
event attributes that do not fail.
Signed-off-by: NAndrew Murray <andrew.murray@arm.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NWill Deacon <will.deacon@arm.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: robin.murphy@arm.com
Cc: suzuki.poulose@arm.com
Link: https://lkml.kernel.org/r/1547128414-50693-9-git-send-email-andrew.murray@arm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

PERF_PMU_CAP_NO_EXCLUDE capability. This ensures that perf will
prevent us from handling events where any exclusion flags are set.
Let's also remove the now unnecessary check for exclusion flags.
Signed-off-by: NAndrew Murray <andrew.murray@arm.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NWill Deacon <will.deacon@arm.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: robin.murphy@arm.com
Cc: suzuki.poulose@arm.com
Link: https://lkml.kernel.org/r/1547128414-50693-8-git-send-email-andrew.murray@arm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

For drivers that do not support context exclusion let's advertise the
PERF_PMU_CAP_NO_EXCLUDE capability. This ensures that perf will
prevent us from handling events where any exclusion flags are set.
Let's also remove the now unnecessary check for exclusion flags.
Signed-off-by: NAndrew Murray <andrew.murray@arm.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NShawn Guo <shawnguo@kernel.org>
Acked-by: NWill Deacon <will.deacon@arm.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: robin.murphy@arm.com
Cc: suzuki.poulose@arm.com
Link: https://lkml.kernel.org/r/1547128414-50693-7-git-send-email-andrew.murray@arm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

The ARM PMU driver can be used to represent a variety of ARM based
PMUs. Some of these PMUs do not provide support for context
exclusion, where this is the case we advertise the
PERF_PMU_CAP_NO_EXCLUDE capability to ensure that perf prevents us
from handling events where any exclusion flags are set.

Where an ARM PMU driver has the set_event_filter function implemented,
we rely on it to perform exclusion checks. At present some of these
functions do not test for all of the available exclude flags.
Signed-off-by: NAndrew Murray <andrew.murray@arm.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NWill Deacon <will.deacon@arm.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: robin.murphy@arm.com
Cc: suzuki.poulose@arm.com
Link: https://lkml.kernel.org/r/1547128414-50693-6-git-send-email-andrew.murray@arm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

As the Alpha PMU doesn't support context exclusion let's advertise
the PERF_PMU_CAP_NO_EXCLUDE capability. This ensures that perf will
prevent us from handling events where any exclusion flags are set.
Let's also remove the now unnecessary check for exclusion flags.

This change means that __hw_perf_event_init will now also
indicate that it doesn't support exclude_host and exclude_guest and
will now implicitly return -EINVAL instead of -EPERM. This is likely
more desirable as -EPERM will result in a kernel.perf_event_paranoid
related warning from the perf userspace utility.
Signed-off-by: NAndrew Murray <andrew.murray@arm.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: robin.murphy@arm.com
Cc: suzuki.poulose@arm.com
Link: https://lkml.kernel.org/r/1547128414-50693-5-git-send-email-andrew.murray@arm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Many PMU drivers do not have the capability to exclude counting events
that occur in specific contexts such as idle, kernel, guest, etc. These
drivers indicate this by returning an error in their event_init upon
testing the events attribute flags. This approach is error prone and
often inconsistent.

Let's instead allow PMU drivers to advertise their inability to exclude
based on context via a new capability: PERF_PMU_CAP_NO_EXCLUDE. This
allows the perf core to reject requests for exclusion events where
there is no support in the PMU.
Signed-off-by: NAndrew Murray <andrew.murray@arm.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: robin.murphy@arm.com
Cc: suzuki.poulose@arm.com
Link: https://lkml.kernel.org/r/1547128414-50693-4-git-send-email-andrew.murray@arm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Add a function that tests if any of the perf event exclusion flags
are set on a given event.
Signed-off-by: NAndrew Murray <andrew.murray@arm.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: robin.murphy@arm.com
Cc: suzuki.poulose@arm.com
Link: https://lkml.kernel.org/r/1547128414-50693-3-git-send-email-andrew.murray@arm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Update design.txt to reflect the presence of the exclude_host
and exclude_guest perf flags.
Signed-off-by: NAndrew Murray <andrew.murray@arm.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: robin.murphy@arm.com
Cc: suzuki.poulose@arm.com
Link: https://lkml.kernel.org/r/1547128414-50693-2-git-send-email-andrew.murray@arm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Pull rdma fixes frfom Jason Gunthorpe:
 "Not much so far. We have the usual batch of bugs and two fixes to code
  merged this cycle:

   - Restore valgrind support for the ioctl verbs interface merged this
     window, and fix a missed error code on an error path from that
     conversion

   - A user reported crash on obsolete mthca hardware

   - pvrdma was using the wrong command opcode toward the hypervisor

   - NULL pointer crash regression when dumping rdma-cm over netlink

   - Be conservative about exposing the global rkey"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  RDMA/uverbs: Mark ioctl responses with UVERBS_ATTR_F_VALID_OUTPUT
  RDMA/mthca: Clear QP objects during their allocation
  RDMA/vmw_pvrdma: Return the correct opcode when creating WR
  RDMA/cma: Add cm_id restrack resource based on kernel or user cm_id type
  RDMA/nldev: Don't expose unsafe global rkey to regular user
  RDMA/uverbs: Fix post send success return value in case of error

Pull drm fixes from Dave Airlie:
 "The rc3 fixes are a bit scattered:

   - meson, sun4i and rockchip all had missing of_node_put.

   - qxl and virtio both were advertising dma-buf to userspace when they
     really shouldn't have.

  Otherwise:

  meson:
   - modesetting regression fix

  i915 GVT:
   - one cmd parser failure fix
   - region cleanup fix in vGPU destroy

  amdgpu:
   - KFD fixes for arm64 mixed APU/DGPU
   - vega12 powerplay fix
   - raven DC fixes
   - freesync fix"

* tag 'drm-fixes-2019-01-18' of git://anongit.freedesktop.org/drm/drm:
  drm/amd/display: Detach backlight from stream
  drm/sun4i: backend: add missing of_node_puts
  Revert "drm/amdgpu: validate user pitch alignment"
  Revert "drm/amdgpu: validate user GEM object size"
  drm/meson: Fix atomic mode switching regression
  drm/i915/gvt: Fix mmap range check
  drm/i915/gvt: free VFIO region space in vgpu detach
  drm/amd/display: Fix disabled cursor on top screen edge
  drm/amd/display: fix warning on raven hotplug
  drm/amd/display: fix PME notification not working in RV desktop
  drm/amd/display: Only get the connector state for VRR when toggled
  drm/amd/display: Pack DMCU iRAM alignment
  drm/amd/powerplay: run acg btc for Vega12
  drm/amdkfd: Don't assign dGPUs to APU topology devices
  drm/amdkfd: Allow building KFD on ARM64 (v2)
  drm/meson: add missing of_node_put
  drm/virtio: drop prime import/export callbacks
  drm/qxl: drop prime import/export callbacks
  drm/i915/gvt: Allow F_CMD_ACCESS on mmio 0x21f0
  drm/rockchip: add missing of_node_put

Merge tag 'led-fix-for-5.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds

Pull LED fix from Jacek Anaszewski.

* tag 'led-fix-for-5.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds:
  leds: lp5523: fix a missing check of return value of lp55xx_read

Merge tag 'hwmon-for-v5.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon fixes from Guenter Roeck:
 "Minor fixes/regressions"

* tag 'hwmon-for-v5.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (tmp421) Correct the misspelling of the tmp442 compatible attribute in OF device ID table
  hwmon: (occ) Fix potential integer overflow
  hwmon: (lm80) Fix missing unlock on error in set_fan_div()
  hwmon: (nct6775) Enable IO mapping for NCT6797D and NCT6798D
  hwmon: (nct6775) Fix chip ID for NCT6798D

drm-misc-fixes for v5.0-rc3:
- Add missing calls to of_node_put to sun4i, meson, and rockchip.
- Drop unimplemented prime callbacks in virtio and qxl, so support
  for prime is not advertised on those drivers.
- Fix mode switching regression in meson.
Signed-off-by: NDave Airlie <airlied@redhat.com>

From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/9af07312-f435-2fda-65a2-9fe92cdf5da4@linux.intel.com

Merge tag 'drm-intel-fixes-2019-01-17' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes

drm/i915/gvt fixes for v5.0-rc3

"This contains one cmd parser failure fix to allow cmd access for one
register, and fix region cleanup properly in vGPU destroy, and another
fix for critical mmap size check mistake."
Signed-off-by: NDave Airlie <airlied@redhat.com>

From: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/87ef9bfusc.fsf@intel.com

Fixes for 5.0:
- Fix KFD on ARM64
- Fix KFD topology with mixed APU and dGPU systems
- Powerplay fix for vega12
- DC Raven fixes
- Freesync fix
Signed-off-by: NDave Airlie <airlied@redhat.com>
From: Alex Deucher <alexdeucher@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190116224524.3314-1-alexander.deucher@amd.com

When lp55xx_read() fails, "status" is an uninitialized variable and thus
may contain random value; using it leads to undefined behaviors.

The fix inserts a check for the return value of lp55xx_read: if it
fails, returns with its error code.
Signed-off-by: NKangjie Lu <kjlu@umn.edu>
Signed-off-by: NJacek Anaszewski <jacek.anaszewski@gmail.com>

Correct a typo in OF device ID table
The last one should be 'ti,tmp442'
Signed-off-by: NCheng-Min Ao <tony_ao@wiwynn.com>
Signed-off-by: NYu-Hsiang Chen <matt_chen@wiwynn.com>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Pull AFS fixes from David Howells:
 "Here's a set of fixes for AFS:

   - Use struct_size() for kzalloc() size calculation.

   - When calling YFS.CreateFile rather than AFS.CreateFile, it is
     possible to create a file with a file lock already held. The
     default value indicating no lock required is actually -1, not 0.

   - Fix an oops in inode/vnode validation if the target inode doesn't
     have a server interest assigned (ie. a server that will notify us
     of changes by third parties).

   - Fix refcounting of keys in file locking.

   - Fix a race in refcounting asynchronous operations in the event of
     an error during request transmission. The provision of a dedicated
     function to get an extra ref on a call is split into a separate
     commit"

* tag 'afs-fixes-20190117' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Fix race in async call refcounting
  afs: Provide a function to get a ref on a call
  afs: Fix key refcounting in file locking code
  afs: Don't set vnode->cb_s_break in afs_validate()
  afs: Set correct lock type for the yfs CreateFile
  afs: Use struct_size() in kzalloc()

Pull swiotlb fix from Konrad Rzeszutek Wilk:
 "A tiny fix for v5.0-rc2:

  This fixes an issue with GPU cards not working anymore with the DMA
  mapping work Christopher did - as the SWIOTLB is initialized first and
  then free'd (as IOMMU is available) but we forgot to clear our start
  and end entries which are used and BOOM"

* 'stable/for-linus-5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb:
  swiotlb: clear io_tlb_start and io_tlb_end in swiotlb_exit

Merge tag 'kbuild-fixes-v5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - clean generated files in scripts/kconfig/ by 'make mrproper'

 - fix conflict between dead code elimination and ftrace for GCC <= 4.7

 - fix external module build with CONFIG_STACKPROTECTOR

 - remove unused code

* tag 'kbuild-fixes-v5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: mark prepare0 as PHONY to fix external module build
  openrisc: remove unneeded code in arch/openrisc/Makefile
  nds32: remove unneeded code in arch/nds32/Makefile
  ia64: remove redundant 'export AWK'
  kbuild: remove unused archmrproper
  kbuild: remove unused baseprereq
  kbuild: Disable LD_DEAD_CODE_DATA_ELIMINATION with ftrace & GCC <= 4.7
  kconfig: clean generated *conf-cfg files

Pull Devicetree fixes from Rob Herring:

 - Remove now unused struct device_node.type pointer

 - Fix meson-axg reset header SPDX tag

 - Add missing of_node_put in of_graph_get_remote_port_parent

 - Fix several binding doc file references and typos

* tag 'devicetree-fixes-for-5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
  dt-bindings: reset: meson-axg: fix SPDX license id
  dt-bindings: soc: qcom: Fix trivial language typos
  doc: gpio-mvebu: fix broken reference to cp110-system-controller0.txt file
  OF: properties: add missing of_node_put
  doc: bindings: fix bad reference to ARM CPU bindings
  dt-bindings: marvell,mmp2: fix typos in bindings doc
  of: Remove struct device_node.type pointer

There's a race between afs_make_call() and afs_wake_up_async_call() in the
case that an error is returned from rxrpc_kernel_send_data() after it has
queued the final packet.

afs_make_call() will try and clean up the mess, but the call state may have
been moved on thereby causing afs_process_async_call() to also try and to
delete the call.

Fix this by:

 (1) Getting an extra ref for an asynchronous call for the call itself to
     hold.  This makes sure the call doesn't evaporate on us accidentally
     and will allow the call to be retained by the caller in a future
     patch.  The ref is released on leaving afs_make_call() or
     afs_wait_for_call_to_complete().

 (2) In the event of an error from rxrpc_kernel_send_data():

     (a) Don't set the call state to AFS_CALL_COMPLETE until *after* the
     	 call has been aborted and ended.  This prevents
     	 afs_deliver_to_call() from doing anything with any notifications
     	 it gets.

     (b) Explicitly end the call immediately to prevent further callbacks.

     (c) Cancel any queued async_work and wait for the work if it's
     	 executing.  This allows us to be sure the race won't recur when we
     	 change the state.  We put the work queue's ref on the call if we
     	 managed to cancel it.

     (d) Put the call's ref that we got in (1).  This belongs to us as long
     	 as the call is in state AFS_CALL_CL_REQUESTING.

Fixes: 341f741f ("afs: Refcount the afs_call struct")
Signed-off-by: NDavid Howells <dhowells@redhat.com>