linux/kernel/events/core.c, branch v4.14

perf/cgroup: Fix perf cgroup hierarchy support

2017-10-30T10:58:51Z

The following commit: 864c2357ca89 ("perf/core: Do not set cpuctx->cgrp for unscheduled cgroups") made list_update_cgroup_event() skip setting cpuctx->cgrp if no cgroup event targets %current's cgroup. This breaks perf_event's hierarchical support because events which target one of the ancestors get ignored. Fix it by using cgroup_is_descendant() test instead of equality. Signed-off-by: Tejun Heo Acked-by: Thomas Gleixner Cc: Arnaldo Carvalho de Melo Cc: David Carrillo-Cisneros Cc: Linus Torvalds Cc: Peter Zijlstra Cc: kernel-team@fb.com Cc: stable@vger.kernel.org # v4.9+ Fixes: 864c2357ca89 ("perf/core: Do not set cpuctx->cgrp for unscheduled cgroups") Link: http://lkml.kernel.org/r/20171028164237.GA972780@devbig577.frc2.facebook.com Signed-off-by: Ingo Molnar

perf/core: Fix cgroup time when scheduling descendants

2017-10-10T08:06:55Z

Update cgroup time when an event is scheduled in by descendants. Reviewed-and-tested-by: Jiri Olsa Signed-off-by: leilei.lin Signed-off-by: Peter Zijlstra (Intel) Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Thomas Gleixner 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

perf/core: Avoid freeing static PMU contexts when PMU is unregistered

2017-10-10T08:06:54Z

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 Signed-off-by: Will Deacon Signed-off-by: Peter Zijlstra (Intel) Acked-by: Mark Rutland Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner 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

bpf: one perf event close won't free bpf program attached by another perf event

2017-09-20T21:10:29Z

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 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 Signed-off-by: David S. Miller

Merge branch 'for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

2017-09-07T05:25:25Z

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() ...

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

2017-09-06T21:45:08Z

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 ...

Merge branch 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2017-09-04T20:56:37Z

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 ...

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2017-09-02T00:42:05Z

Three cases of simple overlapping changes. Signed-off-by: David S. Miller

perf/core, x86: Add PERF_SAMPLE_PHYS_ADDR

2017-08-29T13:09:25Z

For understanding how the workload maps to memory channels and hardware behavior, it's very important to collect address maps with physical addresses. For example, 3D XPoint access can only be found by filtering the physical address. Add a new sample type for physical address. perf already has a facility to collect data virtual address. This patch introduces a function to convert the virtual address to physical address. The function is quite generic and can be extended to any architecture as long as a virtual address is provided. - For kernel direct mapping addresses, virt_to_phys is used to convert the virtual addresses to physical address. - For user virtual addresses, __get_user_pages_fast is used to walk the pages tables for user physical address. - This does not work for vmalloc addresses right now. These are not resolved, but code to do that could be added. The new sample type requires collecting the virtual address. The virtual address will not be output unless SAMPLE_ADDR is applied. For security, the physical address can only be exposed to root or privileged user. Tested-by: Madhavan Srinivasan Signed-off-by: Kan Liang Signed-off-by: Peter Zijlstra (Intel) Cc: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Vince Weaver Cc: acme@kernel.org Cc: mpe@ellerman.id.au Link: http://lkml.kernel.org/r/1503967969-48278-1-git-send-email-kan.liang@intel.com Signed-off-by: Ingo Molnar

perf/core, pt, bts: Get rid of itrace_started

2017-08-29T13:09:24Z

I just noticed that hw.itrace_started and hw.config are aliased to the same location. Now, the PT driver happens to use both, which works out fine by sheer luck: - STORE(hw.itrace_start) is ordered before STORE(hw.config), in the program order, although there are no compiler barriers to ensure that, - to the perf_log_itrace_start() hw.itrace_start looks set at the same time as when it is intended to be set because both stores happen in the same path, - hw.config is never reset to zero in the PT driver. Now, the use of hw.config by the PT driver makes more sense (it being a HW PMU) than messing around with itrace_started, which is an awkward API to begin with. This patch replaces hw.itrace_started with an attach_state bit and an API call for the PMU drivers to use to communicate the condition. Signed-off-by: Alexander Shishkin Signed-off-by: Peter Zijlstra (Intel) Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Vince Weaver Cc: vince@deater.net Link: http://lkml.kernel.org/r/20170330153956.25994-1-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar