kernel/linux.git/include/uapi/linux/perf_event.h, branch v4.17.5

perf/core: Store context switch out type in PERF_RECORD_SWITCH[_CPU_WIDE]

2018-04-17T12:47:39+00:00

Store preempting context switch out event into Perf trace as a part of PERF_RECORD_SWITCH[_CPU_WIDE] record. Percentage of preempting and non-preempting context switches help understanding the nature of workloads (CPU or IO bound) that are running on a machine; The event is treated as preemption one when task->state value of the thread being switched out is TASK_RUNNING. Event type encoding is implemented using PERF_RECORD_MISC_SWITCH_OUT_PREEMPT bit; Signed-off-by: Alexey Budankov Acked-by: Peter Zijlstra Tested-by: Arnaldo Carvalho de Melo Cc: Alexander Shishkin Cc: Andi Kleen Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lkml.kernel.org/r/9ff84e83-a0ca-dd82-a6d0-cb951689be74@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf/core: Implement fast breakpoint modification via _IOC_MODIFY_ATTRIBUTES

2018-03-13T14:24:02+00:00

Problem and motivation: Once a breakpoint perf event (PERF_TYPE_BREAKPOINT) is created, there is no flexibility to change the breakpoint type (bp_type), breakpoint address (bp_addr), or breakpoint length (bp_len). The only option is to close the perf event and configure a new breakpoint event. This inflexibility has a significant performance overhead. For example, sampling-based, lightweight performance profilers (and also concurrency bug detection tools), monitor different addresses for a short duration using PERF_TYPE_BREAKPOINT and change the address (bp_addr) to another address or change the kind of breakpoint (bp_type) from "write" to a "read" or vice-versa or change the length (bp_len) of the address being monitored. The cost of these modifications is prohibitive since it involves unmapping the circular buffer associated with the perf event, closing the perf event, opening another perf event and mmaping another circular buffer. Solution: The new ioctl flag for perf events, PERF_EVENT_IOC_MODIFY_ATTRIBUTES, introduced in this patch takes a pointer to a struct perf_event_attr as an argument to update an old breakpoint event with new address, type, and size. This facility allows retaining a previous mmaped perf events ring buffer and avoids having to close and reopen another perf event. This patch supports only changing PERF_TYPE_BREAKPOINT event type; future implementations can extend this feature. The patch replicates some of its functionality of modify_user_hw_breakpoint() in kernel/events/hw_breakpoint.c. modify_user_hw_breakpoint cannot be called directly since perf_event_ctx_lock() is already held in _perf_ioctl(). Evidence: Experiments show that the baseline (not able to modify an already created breakpoint) costs an order of magnitude (~10x) more than the suggested optimization (having the ability to dynamically modifying a configured breakpoint via ioctl). When the breakpoints typically do not trap, the speedup due to the suggested optimization is ~10x; even when the breakpoints always trap, the speedup is ~4x due to the suggested optimization. Testing: tests posted at https://github.com/linux-contrib/perf_event_modify_bp demonstrate the performance significance of this patch. Tests also check the functional correctness of the patch. Signed-off-by: Milind Chabbi [ Using modify_user_hw_breakpoint_check function. ] [ Reformated PERF_EVENT_IOC_*, so the values are all in one column. ] Signed-off-by: Jiri Olsa Cc: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: David Ahern Cc: Frederic Weisbecker Cc: Hari Bathini Cc: Jin Yao Cc: Jiri Olsa Cc: Kan Liang Cc: Linus Torvalds Cc: Michael Ellerman Cc: Namhyung Kim Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Sukadev Bhattiprolu Cc: Thomas Gleixner Cc: Will Deacon Link: http://lkml.kernel.org/r/20180312134548.31532-8-jolsa@kernel.org Signed-off-by: Ingo Molnar

Merge branch 'perf/urgent' into perf/core, to pick up fixes

2018-02-17T10:39:28+00:00

Signed-off-by: Ingo Molnar

perf/core: Prepare perf_event.h for new types: 'perf_kprobe' and 'perf_uprobe'

2018-02-06T09:18:04+00:00

Two new perf types, perf_kprobe and perf_uprobe, will be added to allow creating [k,u]probe with perf_event_open. These [k,u]probe are associated with the file decriptor created by perf_event_open(), thus are easy to clean when the file descriptor is destroyed. kprobe_func and uprobe_path are added to union config1 for pointers to function name for kprobe or binary path for uprobe. kprobe_addr and probe_offset are added to union config2 for kernel address (when kprobe_func is NULL), or [k,u]probe offset. Signed-off-by: Song Liu Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Yonghong Song Reviewed-by: Josef Bacik Acked-by: Alexei Starovoitov Cc: Cc: Cc: Cc: Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20171206224518.3598254-4-songliubraving@fb.com Signed-off-by: Ingo Molnar

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

2018-01-31T22:31:10+00:00

Pull networking updates from David Miller: 1) Significantly shrink the core networking routing structures. Result of http://vger.kernel.org/~davem/seoul2017_netdev_keynote.pdf 2) Add netdevsim driver for testing various offloads, from Jakub Kicinski. 3) Support cross-chip FDB operations in DSA, from Vivien Didelot. 4) Add a 2nd listener hash table for TCP, similar to what was done for UDP. From Martin KaFai Lau. 5) Add eBPF based queue selection to tun, from Jason Wang. 6) Lockless qdisc support, from John Fastabend. 7) SCTP stream interleave support, from Xin Long. 8) Smoother TCP receive autotuning, from Eric Dumazet. 9) Lots of erspan tunneling enhancements, from William Tu. 10) Add true function call support to BPF, from Alexei Starovoitov. 11) Add explicit support for GRO HW offloading, from Michael Chan. 12) Support extack generation in more netlink subsystems. From Alexander Aring, Quentin Monnet, and Jakub Kicinski. 13) Add 1000BaseX, flow control, and EEE support to mvneta driver. From Russell King. 14) Add flow table abstraction to netfilter, from Pablo Neira Ayuso. 15) Many improvements and simplifications to the NFP driver bpf JIT, from Jakub Kicinski. 16) Support for ipv6 non-equal cost multipath routing, from Ido Schimmel. 17) Add resource abstration to devlink, from Arkadi Sharshevsky. 18) Packet scheduler classifier shared filter block support, from Jiri Pirko. 19) Avoid locking in act_csum, from Davide Caratti. 20) devinet_ioctl() simplifications from Al viro. 21) More TCP bpf improvements from Lawrence Brakmo. 22) Add support for onlink ipv6 route flag, similar to ipv4, from David Ahern. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1925 commits) tls: Add support for encryption using async offload accelerator ip6mr: fix stale iterator net/sched: kconfig: Remove blank help texts openvswitch: meter: Use 64-bit arithmetic instead of 32-bit tcp_nv: fix potential integer overflow in tcpnv_acked r8169: fix RTL8168EP take too long to complete driver initialization. qmi_wwan: Add support for Quectel EP06 rtnetlink: enable IFLA_IF_NETNSID for RTM_NEWLINK ipmr: Fix ptrdiff_t print formatting ibmvnic: Wait for device response when changing MAC qlcnic: fix deadlock bug tcp: release sk_frag.page in tcp_disconnect ipv4: Get the address of interface correctly. net_sched: gen_estimator: fix lockdep splat net: macb: Handle HRESP error net/mlx5e: IPoIB, Fix copy-paste bug in flow steering refactoring ipv6: addrconf: break critical section in addrconf_verify_rtnl() ipv6: change route cache aging logic i40e/i40evf: Update DESC_NEEDED value to reflect larger value bnxt_en: cleanup DIM work on device shutdown ...

perf: Update PERF_RECORD_MISC_* comment for perf_event_header::misc bit 13

2018-01-08T15:37:54+00:00

The perf_event_header::misc bit 13 is shared on different events and next patch is adding yet another bit 13 user. Updating the comment to make it more structured and clear which events use bit 13. Suggested-by: Peter Zijlstra Signed-off-by: Jiri Olsa Cc: Alexander Shishkin Cc: Andi Kleen Cc: David Ahern Cc: Namhyung Kim Link: http://lkml.kernel.org/r/20180107160356.28203-8-jolsa@kernel.org [ Update the tools/include/uapi/linux copy ] Signed-off-by: Arnaldo Carvalho de Melo

perf: Add sample_id to PERF_RECORD_ITRACE_START event comment

2018-01-08T15:32:25+00:00

Adding missing sample_id line into PERF_RECORD_ITRACE_START event comment. Signed-off-by: Jiri Olsa Cc: Alexander Shishkin Cc: Andi Kleen Cc: David Ahern Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/20180107160356.28203-5-jolsa@kernel.org [ Update the tools/include/uapi/linux copy ] Signed-off-by: Arnaldo Carvalho de Melo

bpf/tracing: allow user space to query prog array on the same tp

2017-12-12T16:46:40+00:00

Commit e87c6bc3852b ("bpf: permit multiple bpf attachments for a single perf event") added support to attach multiple bpf programs to a single perf event. Although this provides flexibility, users may want to know what other bpf programs attached to the same tp interface. Besides getting visibility for the underlying bpf system, such information may also help consolidate multiple bpf programs, understand potential performance issues due to a large array, and debug (e.g., one bpf program which overwrites return code may impact subsequent program results). Commit 2541517c32be ("tracing, perf: Implement BPF programs attached to kprobes") utilized the existing perf ioctl interface and added the command PERF_EVENT_IOC_SET_BPF to attach a bpf program to a tracepoint. This patch adds a new ioctl command, given a perf event fd, to query the bpf program array attached to the same perf tracepoint event. The new uapi ioctl command: PERF_EVENT_IOC_QUERY_BPF The new uapi/linux/perf_event.h structure: struct perf_event_query_bpf { __u32 ids_len; __u32 prog_cnt; __u32 ids[0]; }; User space provides buffer "ids" for kernel to copy to. When returning from the kernel, the number of available programs in the array is set in "prog_cnt". The usage: struct perf_event_query_bpf *query = malloc(sizeof(*query) + sizeof(u32) * ids_len); query.ids_len = ids_len; err = ioctl(pmu_efd, PERF_EVENT_IOC_QUERY_BPF, query); if (err == 0) { /* query.prog_cnt is the number of available progs, * number of progs in ids: (ids_len == 0) ? 0 : query.prog_cnt */ } else if (errno == ENOSPC) { /* query.ids_len number of progs copied, * query.prog_cnt is the number of available progs */ } else { /* other errors */ } Signed-off-by: Yonghong Song Acked-by: Peter Zijlstra (Intel) Acked-by: Alexei Starovoitov Signed-off-by: Alexei Starovoitov

Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

2017-11-15T18:56:56+00:00

Pull arm64 updates from Will Deacon: "The big highlight is support for the Scalable Vector Extension (SVE) which required extensive ABI work to ensure we don't break existing applications by blowing away their signal stack with the rather large new vector context (<= 2 kbit per vector register). There's further work to be done optimising things like exception return, but the ABI is solid now. Much of the line count comes from some new PMU drivers we have, but they're pretty self-contained and I suspect we'll have more of them in future. Plenty of acronym soup here: - initial support for the Scalable Vector Extension (SVE) - improved handling for SError interrupts (required to handle RAS events) - enable GCC support for 128-bit integer types - remove kernel text addresses from backtraces and register dumps - use of WFE to implement long delay()s - ACPI IORT updates from Lorenzo Pieralisi - perf PMU driver for the Statistical Profiling Extension (SPE) - perf PMU driver for Hisilicon's system PMUs - misc cleanups and non-critical fixes" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (97 commits) arm64: Make ARMV8_DEPRECATED depend on SYSCTL arm64: Implement __lshrti3 library function arm64: support __int128 on gcc 5+ arm64/sve: Add documentation arm64/sve: Detect SVE and activate runtime support arm64/sve: KVM: Hide SVE from CPU features exposed to guests arm64/sve: KVM: Treat guest SVE use as undefined instruction execution arm64/sve: KVM: Prevent guests from using SVE arm64/sve: Add sysctl to set the default vector length for new processes arm64/sve: Add prctl controls for userspace vector length management arm64/sve: ptrace and ELF coredump support arm64/sve: Preserve SVE registers around EFI runtime service calls arm64/sve: Preserve SVE registers around kernel-mode NEON use arm64/sve: Probe SVE capabilities and usable vector lengths arm64: cpufeature: Move sys_caps_initialised declarations arm64/sve: Backend logic for setting the vector length arm64/sve: Signal handling support arm64/sve: Support vector length resetting for new processes arm64/sve: Core task context handling arm64/sve: Low-level CPU setup ...

License cleanup: add SPDX license identifier to uapi header files with a license

2017-11-02T10:20:11+00:00

Many user space API headers have licensing information, which is either incomplete, badly formatted or just a shorthand for referring to the license under which the file is supposed to be. This makes it hard for compliance tools to determine the correct license. Update these files with an SPDX license identifier. The identifier was chosen based on the license information in the file. GPL/LGPL licensed headers get the matching GPL/LGPL SPDX license identifier with the added 'WITH Linux-syscall-note' exception, which is the officially assigned exception identifier for the kernel syscall exception: NOTE! This copyright does *not* cover user programs that use kernel services by normal system calls - this is merely considered normal use of the kernel, and does *not* fall under the heading of "derived work". This exception makes it possible to include GPL headers into non GPL code, without confusing license compliance tools. Headers which have either explicit dual licensing or are just licensed under a non GPL license are updated with the corresponding SPDX identifier and the GPLv2 with syscall exception identifier. The format is: ((GPL-2.0 WITH Linux-syscall-note) OR SPDX-ID-OF-OTHER-LICENSE) SPDX license identifiers are a legally binding shorthand, which can be used instead of the full boiler plate text. The update does not remove existing license information as this has to be done on a case by case basis and the copyright holders might have to be consulted. This will happen in a separate step. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. See the previous patch in this series for the methodology of how this patch was researched. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman