Update cgroup time when an event is scheduled in by descendants.

Reviewed-and-tested-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: leilei.lin <leilei.lin@alibaba-inc.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: alexander.shishkin@linux.intel.com
Cc: brendan.d.gregg@gmail.com
Cc: yang_oliver@hotmail.com
Link: http://lkml.kernel.org/r/CALPjY3mkHiekRkRECzMi9G-bjUQOvOjVBAqxmWkTzc-g+0LwMg@mail.gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Since commit:

  1fd7e4169954 ("perf/core: Remove perf_cpu_context::unique_pmu")

... when a PMU is unregistered then its associated ->pmu_cpu_context is
unconditionally freed. Whilst this is fine for dynamically allocated
context types (i.e. those registered using perf_invalid_context), this
causes a problem for sharing of static contexts such as
perf_{sw,hw}_context, which are used by multiple built-in PMUs and
effectively have a global lifetime.

Whilst testing the ARM SPE driver, which must use perf_sw_context to
support per-task AUX tracing, unregistering the driver as a result of a
module unload resulted in:

 Unable to handle kernel NULL pointer dereference at virtual address 00000038
 Internal error: Oops: 96000004 [#1] PREEMPT SMP
 Modules linked in: [last unloaded: arm_spe_pmu]
 PC is at ctx_resched+0x38/0xe8
 LR is at perf_event_exec+0x20c/0x278
 [...]
 ctx_resched+0x38/0xe8
 perf_event_exec+0x20c/0x278
 setup_new_exec+0x88/0x118
 load_elf_binary+0x26c/0x109c
 search_binary_handler+0x90/0x298
 do_execveat_common.isra.14+0x540/0x618
 SyS_execve+0x38/0x48

since the software context has been freed and the ctx.pmu->pmu_disable_count
field has been set to NULL.

This patch fixes the problem by avoiding the freeing of static PMU contexts
altogether. Whilst the sharing of dynamic contexts is questionable, this
actually requires the caller to share their context pointer explicitly
and so the burden is on them to manage the object lifetime.

Reported-by: Kim Phillips <kim.phillips@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 1fd7e4169954 ("perf/core: Remove perf_cpu_context::unique_pmu")
Link: http://lkml.kernel.org/r/1507040450-7730-1-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

The following commit:

  d9a50b0256 ("perf/aux: Ensure aux_wakeup represents most recent wakeup index")

changed the AUX wakeup position calculation to rounddown(), which causes
a division-by-zero in AUX overwrite mode (aka "snapshot mode").

The zero denominator results from the fact that perf record doesn't set
aux_watermark to anything, in which case the kernel will set it to half
the AUX buffer size, but only for non-overwrite mode. In the overwrite
mode aux_watermark stays zero.

The good news is that, AUX overwrite mode, wakeups don't happen and
related bookkeeping is not relevant, so we can simply forego the whole
wakeup updates.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/20170906160811.16510-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

This patch fixes a bug exhibited by the following scenario:
  1. fd1 = perf_event_open with attr.config = ID1
  2. attach bpf program prog1 to fd1
  3. fd2 = perf_event_open with attr.config = ID1
     <this will be successful>
  4. user program closes fd2 and prog1 is detached from the tracepoint.
  5. user program with fd1 does not work properly as tracepoint
     no output any more.

The issue happens at step 4. Multiple perf_event_open can be called
successfully, but only one bpf prog pointer in the tp_event. In the
current logic, any fd release for the same tp_event will free
the tp_event->prog.

The fix is to free tp_event->prog only when the closing fd
corresponds to the one which registered the program.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull cgroup updates from Tejun Heo:
 "Several notable changes this cycle:

   - Thread mode was merged. This will be used for cgroup2 support for
     CPU and possibly other controllers. Unfortunately, CPU controller
     cgroup2 support didn't make this pull request but most contentions
     have been resolved and the support is likely to be merged before
     the next merge window.

   - cgroup.stat now shows the number of descendant cgroups.

   - cpuset now can enable the easier-to-configure v2 behavior on v1
     hierarchy"

* 'for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (21 commits)
  cpuset: Allow v2 behavior in v1 cgroup
  cgroup: Add mount flag to enable cpuset to use v2 behavior in v1 cgroup
  cgroup: remove unneeded checks
  cgroup: misc changes
  cgroup: short-circuit cset_cgroup_from_root() on the default hierarchy
  cgroup: re-use the parent pointer in cgroup_destroy_locked()
  cgroup: add cgroup.stat interface with basic hierarchy stats
  cgroup: implement hierarchy limits
  cgroup: keep track of number of descent cgroups
  cgroup: add comment to cgroup_enable_threaded()
  cgroup: remove unnecessary empty check when enabling threaded mode
  cgroup: update debug controller to print out thread mode information
  cgroup: implement cgroup v2 thread support
  cgroup: implement CSS_TASK_ITER_THREADED
  cgroup: introduce cgroup->dom_cgrp and threaded css_set handling
  cgroup: add @flags to css_task_iter_start() and implement CSS_TASK_ITER_PROCS
  cgroup: reorganize cgroup.procs / task write path
  cgroup: replace css_set walking populated test with testing cgrp->nr_populated_csets
  cgroup: distinguish local and children populated states
  cgroup: remove now unused list_head @pending in cgroup_apply_cftypes()
  ...

Pull networking updates from David Miller:

 1) Support ipv6 checksum offload in sunvnet driver, from Shannon
    Nelson.

 2) Move to RB-tree instead of custom AVL code in inetpeer, from Eric
    Dumazet.

 3) Allow generic XDP to work on virtual devices, from John Fastabend.

 4) Add bpf device maps and XDP_REDIRECT, which can be used to build
    arbitrary switching frameworks using XDP. From John Fastabend.

 5) Remove UFO offloads from the tree, gave us little other than bugs.

 6) Remove the IPSEC flow cache, from Florian Westphal.

 7) Support ipv6 route offload in mlxsw driver.

 8) Support VF representors in bnxt_en, from Sathya Perla.

 9) Add support for forward error correction modes to ethtool, from
    Vidya Sagar Ravipati.

10) Add time filter for packet scheduler action dumping, from Jamal Hadi
    Salim.

11) Extend the zerocopy sendmsg() used by virtio and tap to regular
    sockets via MSG_ZEROCOPY. From Willem de Bruijn.

12) Significantly rework value tracking in the BPF verifier, from Edward
    Cree.

13) Add new jump instructions to eBPF, from Daniel Borkmann.

14) Rework rtnetlink plumbing so that operations can be run without
    taking the RTNL semaphore. From Florian Westphal.

15) Support XDP in tap driver, from Jason Wang.

16) Add 32-bit eBPF JIT for ARM, from Shubham Bansal.

17) Add Huawei hinic ethernet driver.

18) Allow to report MD5 keys in TCP inet_diag dumps, from Ivan
    Delalande.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1780 commits)
  i40e: point wb_desc at the nvm_wb_desc during i40e_read_nvm_aq
  i40e: avoid NVM acquire deadlock during NVM update
  drivers: net: xgene: Remove return statement from void function
  drivers: net: xgene: Configure tx/rx delay for ACPI
  drivers: net: xgene: Read tx/rx delay for ACPI
  rocker: fix kcalloc parameter order
  rds: Fix non-atomic operation on shared flag variable
  net: sched: don't use GFP_KERNEL under spin lock
  vhost_net: correctly check tx avail during rx busy polling
  net: mdio-mux: add mdio_mux parameter to mdio_mux_init()
  rxrpc: Make service connection lookup always check for retry
  net: stmmac: Delete dead code for MDIO registration
  gianfar: Fix Tx flow control deactivation
  cxgb4: Ignore MPS_TX_INT_CAUSE[Bubble] for T6
  cxgb4: Fix pause frame count in t4_get_port_stats
  cxgb4: fix memory leak
  tun: rename generic_xdp to skb_xdp
  tun: reserve extra headroom only when XDP is set
  net: dsa: bcm_sf2: Configure IMP port TC2QOS mapping
  net: dsa: bcm_sf2: Advertise number of egress queues
  ...

Pull x86 cache quality monitoring update from Thomas Gleixner:
 "This update provides a complete rewrite of the Cache Quality
  Monitoring (CQM) facility.

  The existing CQM support was duct taped into perf with a lot of issues
  and the attempts to fix those turned out to be incomplete and
  horrible.

  After lengthy discussions it was decided to integrate the CQM support
  into the Resource Director Technology (RDT) facility, which is the
  obvious choise as in hardware CQM is part of RDT. This allowed to add
  Memory Bandwidth Monitoring support on top.

  As a result the mechanisms for allocating cache/memory bandwidth and
  the corresponding monitoring mechanisms are integrated into a single
  management facility with a consistent user interface"

* 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits)
  x86/intel_rdt: Turn off most RDT features on Skylake
  x86/intel_rdt: Add command line options for resource director technology
  x86/intel_rdt: Move special case code for Haswell to a quirk function
  x86/intel_rdt: Remove redundant ternary operator on return
  x86/intel_rdt/cqm: Improve limbo list processing
  x86/intel_rdt/mbm: Fix MBM overflow handler during CPU hotplug
  x86/intel_rdt: Modify the intel_pqr_state for better performance
  x86/intel_rdt/cqm: Clear the default RMID during hotcpu
  x86/intel_rdt: Show bitmask of shareable resource with other executing units
  x86/intel_rdt/mbm: Handle counter overflow
  x86/intel_rdt/mbm: Add mbm counter initialization
  x86/intel_rdt/mbm: Basic counting of MBM events (total and local)
  x86/intel_rdt/cqm: Add CPU hotplug support
  x86/intel_rdt/cqm: Add sched_in support
  x86/intel_rdt: Introduce rdt_enable_key for scheduling
  x86/intel_rdt/cqm: Add mount,umount support
  x86/intel_rdt/cqm: Add rmdir support
  x86/intel_rdt: Separate the ctrl bits from rmdir
  x86/intel_rdt/cqm: Add mon_data
  x86/intel_rdt: Prepare for RDT monitor data support
  ...

Pull perf updates from Ingo Molnar:
 "Kernel side changes:

   - Add branch type profiling/tracing support. (Jin Yao)

   - Add the PERF_SAMPLE_PHYS_ADDR ABI to allow the tracing/profiling of
     physical memory addresses, where the PMU supports it. (Kan Liang)

   - Export some PMU capability details in the new
     /sys/bus/event_source/devices/cpu/caps/ sysfs directory. (Andi
     Kleen)

   - Aux data fixes and updates (Will Deacon)

   - kprobes fixes and updates (Masami Hiramatsu)

   - AMD uncore PMU driver fixes and updates (Janakarajan Natarajan)

  On the tooling side, here's a (limited!) list of highlights - there
  were many other changes that I could not list, see the shortlog and
  git history for details:

  UI improvements:

   - Implement a visual marker for fused x86 instructions in the
     annotate TUI browser, available now in 'perf report', more work
     needed to have it available as well in 'perf top' (Jin Yao)

     Further explanation from one of Jin's patches:

             │   ┌──cmpl   $0x0,argp_program_version_hook
       81.93 │   ├──je     20
             │   │  lock   cmpxchg %esi,0x38a9a4(%rip)
             │   │↓ jne    29
             │   │↓ jmp    43
       11.47 │20:└─→cmpxch %esi,0x38a999(%rip)

     That means the cmpl+je is a fused instruction pair and they should
     be considered together.

   - Record the branch type and then show statistics and info about in
     callchain entries (Jin Yao)

     Example from one of Jin's patches:

        # perf record -g -j any,save_type
        # perf report --branch-history --stdio --no-children

        38.50%  div.c:45                [.] main                    div
                |
                ---main div.c:42 (RET CROSS_2M cycles:2)
                   compute_flag div.c:28 (cycles:2)
                   compute_flag div.c:27 (RET CROSS_2M cycles:1)
                   rand rand.c:28 (cycles:1)
                   rand rand.c:28 (RET CROSS_2M cycles:1)
                   __random random.c:298 (cycles:1)
                   __random random.c:297 (COND_BWD CROSS_2M cycles:1)
                   __random random.c:295 (cycles:1)
                   __random random.c:295 (COND_BWD CROSS_2M cycles:1)
                   __random random.c:295 (cycles:1)
                   __random random.c:295 (RET CROSS_2M cycles:9)

  namespaces support:

   - Add initial support for namespaces, using setns to access files in
     namespaces, grabbing their build-ids, etc. (Krister Johansen)

  perf trace enhancements:

   - Beautify pkey_{alloc,free,mprotect} arguments in 'perf trace'
     (Arnaldo Carvalho de Melo)

   - Add initial 'clone' syscall args beautifier in 'perf trace'
     (Arnaldo Carvalho de Melo)

   - Ignore 'fd' and 'offset' args for MAP_ANONYMOUS in 'perf trace'
     (Arnaldo Carvalho de Melo)

   - Beautifiers for the 'cmd' arg of several ioctl types, including:
     sound, DRM, KVM, vhost virtio and perf_events. (Arnaldo Carvalho de
     Melo)

   - Add PERF_SAMPLE_CALLCHAIN and PERF_RECORD_MMAP[2] to 'perf data'
     CTF conversion, allowing CTF trace visualization tools to show
     callchains and to resolve symbols (Geneviève Bastien)

   - Beautify the fcntl syscall, which is an interesting one in the
     sense that infrastructure had to be put in place to change the
     formatters of some arguments according to the value in a previous
     one, i.e. cmd dictates how arg and the syscall return will be
     formatted. (Arnaldo Carvalho de Melo

  perf stat enhancements:

   - Use group read for event groups in 'perf stat', reducing overhead
     when groups are defined in the event specification, i.e. when using
     {} to enclose a list of events, asking them to be read at the same
     time, e.g.: "perf stat -e '{cycles,instructions}'" (Jiri Olsa)

  pipe mode improvements:

   - Process tracing data in 'perf annotate' pipe mode (David
     Carrillo-Cisneros)

   - Add header record types to pipe-mode, now this command:

        $ perf record -o - -e cycles sleep 1 | perf report --stdio --header

     Will show the same as in non-pipe mode, i.e. involving a perf.data
     file (David Carrillo-Cisneros)

  Vendor specific hardware event support updates/enhancements:

   - Update POWER9 vendor events tables (Sukadev Bhattiprolu)

   - Add POWER9 PMU events Sukadev (Bhattiprolu)

   - Support additional POWER8+ PVR in PMU mapfile (Shriya)

   - Add Skylake server uncore JSON vendor events (Andi Kleen)

   - Support exporting Intel PT data to sqlite3 with python perf
     scripts, this is in addition to the postgresql support that was
     already there (Adrian Hunter)"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (253 commits)
  perf symbols: Fix plt entry calculation for ARM and AARCH64
  perf probe: Fix kprobe blacklist checking condition
  perf/x86: Fix caps/ for !Intel
  perf/core, x86: Add PERF_SAMPLE_PHYS_ADDR
  perf/core, pt, bts: Get rid of itrace_started
  perf trace beauty: Beautify pkey_{alloc,free,mprotect} arguments
  tools headers: Sync cpu features kernel ABI headers with tooling headers
  perf tools: Pass full path of FEATURES_DUMP
  perf tools: Robustify detection of clang binary
  tools lib: Allow external definition of CC, AR and LD
  perf tools: Allow external definition of flex and bison binary names
  tools build tests: Don't hardcode gcc name
  perf report: Group stat values on global event id
  perf values: Zero value buffers
  perf values: Fix allocation check
  perf values: Fix thread index bug
  perf report: Add dump_read function
  perf record: Set read_format for inherit_stat
  perf c2c: Fix remote HITM detection for Skylake
  perf tools: Fix static build with newer toolchains
  ...

Pull perf fixes from Thomas Gleixner:

 - Prevent a potential inconistency in the perf user space access which
   might lead to evading sanity checks.

 - Prevent perf recording function trace entries twice

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/ftrace: Fix double traces of perf on ftrace:function
  perf/core: Fix potential double-fetch bug

Three cases of simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>