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authorLinus Torvalds <torvalds@linux-foundation.org>2015-04-14 14:37:47 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-04-14 14:37:47 -0700
commit6c8a53c9e6a151fffb07f8b4c34bd1e33dddd467 (patch)
tree791caf826ef136c521a97b7878f226b6ba1c1d75 /arch/x86/kernel/cpu/intel_pt.h
parente95e7f627062be5e6ce971ce873e6234c91ffc50 (diff)
parent066450be419fa48007a9f29e19828f2a86198754 (diff)
downloadlinux-6c8a53c9e6a151fffb07f8b4c34bd1e33dddd467.tar.bz2
Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf changes from Ingo Molnar: "Core kernel changes: - One of the more interesting features in this cycle is the ability to attach eBPF programs (user-defined, sandboxed bytecode executed by the kernel) to kprobes. This allows user-defined instrumentation on a live kernel image that can never crash, hang or interfere with the kernel negatively. (Right now it's limited to root-only, but in the future we might allow unprivileged use as well.) (Alexei Starovoitov) - Another non-trivial feature is per event clockid support: this allows, amongst other things, the selection of different clock sources for event timestamps traced via perf. This feature is sought by people who'd like to merge perf generated events with external events that were measured with different clocks: - cluster wide profiling - for system wide tracing with user-space events, - JIT profiling events etc. Matching perf tooling support is added as well, available via the -k, --clockid <clockid> parameter to perf record et al. (Peter Zijlstra) Hardware enablement kernel changes: - x86 Intel Processor Trace (PT) support: which is a hardware tracer on steroids, available on Broadwell CPUs. The hardware trace stream is directly output into the user-space ring-buffer, using the 'AUX' data format extension that was added to the perf core to support hardware constraints such as the necessity to have the tracing buffer physically contiguous. This patch-set was developed for two years and this is the result. A simple way to make use of this is to use BTS tracing, the PT driver emulates BTS output - available via the 'intel_bts' PMU. More explicit PT specific tooling support is in the works as well - will probably be ready by 4.2. (Alexander Shishkin, Peter Zijlstra) - x86 Intel Cache QoS Monitoring (CQM) support: this is a hardware feature of Intel Xeon CPUs that allows the measurement and allocation/partitioning of caches to individual workloads. These kernel changes expose the measurement side as a new PMU driver, which exposes various QoS related PMU events. (The partitioning change is work in progress and is planned to be merged as a cgroup extension.) (Matt Fleming, Peter Zijlstra; CPU feature detection by Peter P Waskiewicz Jr) - x86 Intel Haswell LBR call stack support: this is a new Haswell feature that allows the hardware recording of call chains, plus tooling support. To activate this feature you have to enable it via the new 'lbr' call-graph recording option: perf record --call-graph lbr perf report or: perf top --call-graph lbr This hardware feature is a lot faster than stack walk or dwarf based unwinding, but has some limitations: - It reuses the current LBR facility, so LBR call stack and branch record can not be enabled at the same time. - It is only available for user-space callchains. (Yan, Zheng) - x86 Intel Broadwell CPU support and various event constraints and event table fixes for earlier models. (Andi Kleen) - x86 Intel HT CPUs event scheduling workarounds. This is a complex CPU bug affecting the SNB,IVB,HSW families that results in counter value corruption. The mitigation code is automatically enabled and is transparent. (Maria Dimakopoulou, Stephane Eranian) The perf tooling side had a ton of changes in this cycle as well, so I'm only able to list the user visible changes here, in addition to the tooling changes outlined above: User visible changes affecting all tools: - Improve support of compressed kernel modules (Jiri Olsa) - Save DSO loading errno to better report errors (Arnaldo Carvalho de Melo) - Bash completion for subcommands (Yunlong Song) - Add 'I' event modifier for perf_event_attr.exclude_idle bit (Jiri Olsa) - Support missing -f to override perf.data file ownership. (Yunlong Song) - Show the first event with an invalid filter (David Ahern, Arnaldo Carvalho de Melo) User visible changes in individual tools: 'perf data': New tool for converting perf.data to other formats, initially for the CTF (Common Trace Format) from LTTng (Jiri Olsa, Sebastian Siewior) 'perf diff': Add --kallsyms option (David Ahern) 'perf list': Allow listing events with 'tracepoint' prefix (Yunlong Song) Sort the output of the command (Yunlong Song) 'perf kmem': Respect -i option (Jiri Olsa) Print big numbers using thousands' group (Namhyung Kim) Allow -v option (Namhyung Kim) Fix alignment of slab result table (Namhyung Kim) 'perf probe': Support multiple probes on different binaries on the same command line (Masami Hiramatsu) Support unnamed union/structure members data collection. (Masami Hiramatsu) Check kprobes blacklist when adding new events. (Masami Hiramatsu) 'perf record': Teach 'perf record' about perf_event_attr.clockid (Peter Zijlstra) Support recording running/enabled time (Andi Kleen) 'perf sched': Improve the performance of 'perf sched replay' on high CPU core count machines (Yunlong Song) 'perf report' and 'perf top': Allow annotating entries in callchains in the hists browser (Arnaldo Carvalho de Melo) Indicate which callchain entries are annotated in the TUI hists browser (Arnaldo Carvalho de Melo) Add pid/tid filtering to 'report' and 'script' commands (David Ahern) Consider PERF_RECORD_ events with cpumode == 0 in 'perf top', removing one cause of long term memory usage buildup, i.e. not processing PERF_RECORD_EXIT events (Arnaldo Carvalho de Melo) 'perf stat': Report unsupported events properly (Suzuki K. Poulose) Output running time and run/enabled ratio in CSV mode (Andi Kleen) 'perf trace': Handle legacy syscalls tracepoints (David Ahern, Arnaldo Carvalho de Melo) Only insert blank duration bracket when tracing syscalls (Arnaldo Carvalho de Melo) Filter out the trace pid when no threads are specified (Arnaldo Carvalho de Melo) Dump stack on segfaults (Arnaldo Carvalho de Melo) No need to explicitely enable evsels for workload started from perf, let it be enabled via perf_event_attr.enable_on_exec, removing some events that take place in the 'perf trace' before a workload is really started by it. (Arnaldo Carvalho de Melo) Allow mixing with tracepoints and suppressing plain syscalls. (Arnaldo Carvalho de Melo) There's also been a ton of infrastructure work done, such as the split-out of perf's build system into tools/build/ and other changes - see the shortlog and changelog for details" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (358 commits) perf/x86/intel/pt: Clean up the control flow in pt_pmu_hw_init() perf evlist: Fix type for references to data_head/tail perf probe: Check the orphaned -x option perf probe: Support multiple probes on different binaries perf buildid-list: Fix segfault when show DSOs with hits perf tools: Fix cross-endian analysis perf tools: Fix error path to do closedir() when synthesizing threads perf tools: Fix synthesizing fork_event.ppid for non-main thread perf tools: Add 'I' event modifier for exclude_idle bit perf report: Don't call map__kmap if map is NULL. perf tests: Fix attr tests perf probe: Fix ARM 32 building error perf tools: Merge all perf_event_attr print functions perf record: Add clockid parameter perf sched replay: Use replay_repeat to calculate the runavg of cpu usage instead of the default value 10 perf sched replay: Support using -f to override perf.data file ownership perf sched replay: Fix the EMFILE error caused by the limitation of the maximum open files perf sched replay: Handle the dead halt of sem_wait when create_tasks() fails for any task perf sched replay: Fix the segmentation fault problem caused by pr_err in threads perf sched replay: Realloc the memory of pid_to_task stepwise to adapt to the different pid_max configurations ...
Diffstat (limited to 'arch/x86/kernel/cpu/intel_pt.h')
-rw-r--r--arch/x86/kernel/cpu/intel_pt.h131
1 files changed, 131 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/intel_pt.h b/arch/x86/kernel/cpu/intel_pt.h
new file mode 100644
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+++ b/arch/x86/kernel/cpu/intel_pt.h
@@ -0,0 +1,131 @@
+/*
+ * Intel(R) Processor Trace PMU driver for perf
+ * Copyright (c) 2013-2014, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * Intel PT is specified in the Intel Architecture Instruction Set Extensions
+ * Programming Reference:
+ * http://software.intel.com/en-us/intel-isa-extensions
+ */
+
+#ifndef __INTEL_PT_H__
+#define __INTEL_PT_H__
+
+/*
+ * Single-entry ToPA: when this close to region boundary, switch
+ * buffers to avoid losing data.
+ */
+#define TOPA_PMI_MARGIN 512
+
+/*
+ * Table of Physical Addresses bits
+ */
+enum topa_sz {
+ TOPA_4K = 0,
+ TOPA_8K,
+ TOPA_16K,
+ TOPA_32K,
+ TOPA_64K,
+ TOPA_128K,
+ TOPA_256K,
+ TOPA_512K,
+ TOPA_1MB,
+ TOPA_2MB,
+ TOPA_4MB,
+ TOPA_8MB,
+ TOPA_16MB,
+ TOPA_32MB,
+ TOPA_64MB,
+ TOPA_128MB,
+ TOPA_SZ_END,
+};
+
+static inline unsigned int sizes(enum topa_sz tsz)
+{
+ return 1 << (tsz + 12);
+};
+
+struct topa_entry {
+ u64 end : 1;
+ u64 rsvd0 : 1;
+ u64 intr : 1;
+ u64 rsvd1 : 1;
+ u64 stop : 1;
+ u64 rsvd2 : 1;
+ u64 size : 4;
+ u64 rsvd3 : 2;
+ u64 base : 36;
+ u64 rsvd4 : 16;
+};
+
+#define TOPA_SHIFT 12
+#define PT_CPUID_LEAVES 2
+
+enum pt_capabilities {
+ PT_CAP_max_subleaf = 0,
+ PT_CAP_cr3_filtering,
+ PT_CAP_topa_output,
+ PT_CAP_topa_multiple_entries,
+ PT_CAP_payloads_lip,
+};
+
+struct pt_pmu {
+ struct pmu pmu;
+ u32 caps[4 * PT_CPUID_LEAVES];
+};
+
+/**
+ * struct pt_buffer - buffer configuration; one buffer per task_struct or
+ * cpu, depending on perf event configuration
+ * @cpu: cpu for per-cpu allocation
+ * @tables: list of ToPA tables in this buffer
+ * @first: shorthand for first topa table
+ * @last: shorthand for last topa table
+ * @cur: current topa table
+ * @nr_pages: buffer size in pages
+ * @cur_idx: current output region's index within @cur table
+ * @output_off: offset within the current output region
+ * @data_size: running total of the amount of data in this buffer
+ * @lost: if data was lost/truncated
+ * @head: logical write offset inside the buffer
+ * @snapshot: if this is for a snapshot/overwrite counter
+ * @stop_pos: STOP topa entry in the buffer
+ * @intr_pos: INT topa entry in the buffer
+ * @data_pages: array of pages from perf
+ * @topa_index: table of topa entries indexed by page offset
+ */
+struct pt_buffer {
+ int cpu;
+ struct list_head tables;
+ struct topa *first, *last, *cur;
+ unsigned int cur_idx;
+ size_t output_off;
+ unsigned long nr_pages;
+ local_t data_size;
+ local_t lost;
+ local64_t head;
+ bool snapshot;
+ unsigned long stop_pos, intr_pos;
+ void **data_pages;
+ struct topa_entry *topa_index[0];
+};
+
+/**
+ * struct pt - per-cpu pt context
+ * @handle: perf output handle
+ * @handle_nmi: do handle PT PMI on this cpu, there's an active event
+ */
+struct pt {
+ struct perf_output_handle handle;
+ int handle_nmi;
+};
+
+#endif /* __INTEL_PT_H__ */