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2018-11-03Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates and fixes from Ingo Molnar: "These are almost all tooling updates: 'perf top', 'perf trace' and 'perf script' fixes and updates, an UAPI header sync with the merge window versions, license marker updates, much improved Sparc support from David Miller, and a number of fixes" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (66 commits) perf intel-pt/bts: Calculate cpumode for synthesized samples perf intel-pt: Insert callchain context into synthesized callchains perf tools: Don't clone maps from parent when synthesizing forks perf top: Start display thread earlier tools headers uapi: Update linux/if_link.h header copy tools headers uapi: Update linux/netlink.h header copy tools headers: Sync the various kvm.h header copies tools include uapi: Update linux/mmap.h copy perf trace beauty: Use the mmap flags table generated from headers perf beauty: Wire up the mmap flags table generator to the Makefile perf beauty: Add a generator for MAP_ mmap's flag constants tools include uapi: Update asound.h copy tools arch uapi: Update asm-generic/unistd.h and arm64 unistd.h copies tools include uapi: Update linux/fs.h copy perf callchain: Honour the ordering of PERF_CONTEXT_{USER,KERNEL,etc} perf cs-etm: Correct CPU mode for samples perf unwind: Take pgoff into account when reporting elf to libdwfl perf top: Do not use overwrite mode by default perf top: Allow disabling the overwrite mode perf trace: Beautify mount's first pathname arg ...
2018-10-30Merge tag 'trace-v4.20' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "The biggest change here is the updates to kprobes Back in January I posted patches to create function based events. These were the events that you suggested I make to allow developers to easily create events in code where no trace event exists. After posting those changes for review, it was suggested that we implement this instead with kprobes. The problem with kprobes is that the interface is too complex and needs to be simplified. Masami Hiramatsu posted patches in March and I've been playing with them a bit. There's been a bit of clean up in the kprobe code that was inspired by the function based event patches, and a couple of enhancements to the kprobe event interface. - If the arch supports it (we added support for x86), you can place a kprobe event at the start of a function and use $arg1, $arg2, etc to reference the arguments of a function. (Before you needed to know what register or where on the stack the argument was). - The second is a way to see array of events. For example, if you reference a mac address, you can add: echo 'p:mac ip_rcv perm_addr=+574($arg2):x8[6]' > kprobe_events And this will produce: mac: (ip_rcv+0x0/0x140) perm_addr={0x52,0x54,0x0,0xc0,0x76,0xec} Other changes include - Exporting trace_dump_stack to modules - Have the stack tracer trace the entire stack (stop trying to remove tracing itself, as we keep removing too much). - Added support for SDT in uprobes" [ SDT - "Statically Defined Tracing" are userspace markers for tracing. Let's not use random TLA's in explanations unless they are fairly well-established as generic (at least for kernel people) - Linus ] * tag 'trace-v4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (24 commits) tracing: Have stack tracer trace full stack tracing: Export trace_dump_stack to modules tracing: probeevent: Fix uninitialized used of offset in parse args tracing/kprobes: Allow kprobe-events to record module symbol tracing/kprobes: Check the probe on unloaded module correctly tracing/uprobes: Fix to return -EFAULT if copy_from_user failed tracing: probeevent: Add $argN for accessing function args x86: ptrace: Add function argument access API tracing: probeevent: Add array type support tracing: probeevent: Add symbol type tracing: probeevent: Unify fetch_insn processing common part tracing: probeevent: Append traceprobe_ for exported function tracing: probeevent: Return consumed bytes of dynamic area tracing: probeevent: Unify fetch type tables tracing: probeevent: Introduce new argument fetching code tracing: probeevent: Remove NOKPROBE_SYMBOL from print functions tracing: probeevent: Cleanup argument field definition tracing: probeevent: Cleanup print argument functions trace_uprobe: support reference counter in fd-based uprobe perf probe: Support SDT markers having reference counter (semaphore) ...
2018-10-30perf/core: Clean up inconsisent indentationColin Ian King
Replace a bunch of spaces with tab, cleans up indentation Signed-off-by: Colin Ian King <colin.king@canonical.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kernel-janitors@vger.kernel.org Link: http://lkml.kernel.org/r/20181029233211.21475-1-colin.king@canonical.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-10trace_uprobe: support reference counter in fd-based uprobeSong Liu
This patch enables uprobes with reference counter in fd-based uprobe. Highest 32 bits of perf_event_attr.config is used to stored offset of the reference count (semaphore). Format information in /sys/bus/event_source/devices/uprobe/format/ is updated to reflect this new feature. Link: http://lkml.kernel.org/r/20181002053636.1896903-1-songliubraving@fb.com Cc: Oleg Nesterov <oleg@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-and-tested-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-02perf/ring_buffer: Prevent concurent ring buffer accessJiri Olsa
Some of the scheduling tracepoints allow the perf_tp_event code to write to ring buffer under different cpu than the code is running on. This results in corrupted ring buffer data demonstrated in following perf commands: # perf record -e 'sched:sched_switch,sched:sched_wakeup' perf bench sched messaging # Running 'sched/messaging' benchmark: # 20 sender and receiver processes per group # 10 groups == 400 processes run Total time: 0.383 [sec] [ perf record: Woken up 8 times to write data ] 0x42b890 [0]: failed to process type: -1765585640 [ perf record: Captured and wrote 4.825 MB perf.data (29669 samples) ] # perf report --stdio 0x42b890 [0]: failed to process type: -1765585640 The reason for the corruption are some of the scheduling tracepoints, that have __perf_task dfined and thus allow to store data to another cpu ring buffer: sched_waking sched_wakeup sched_wakeup_new sched_stat_wait sched_stat_sleep sched_stat_iowait sched_stat_blocked The perf_tp_event function first store samples for current cpu related events defined for tracepoint: hlist_for_each_entry_rcu(event, head, hlist_entry) perf_swevent_event(event, count, &data, regs); And then iterates events of the 'task' and store the sample for any task's event that passes tracepoint checks: ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { if (event->attr.type != PERF_TYPE_TRACEPOINT) continue; if (event->attr.config != entry->type) continue; perf_swevent_event(event, count, &data, regs); } Above code can race with same code running on another cpu, ending up with 2 cpus trying to store under the same ring buffer, which is specifically not allowed. This patch prevents the problem, by allowing only events with the same current cpu to receive the event. NOTE: this requires the use of (per-task-)per-cpu buffers for this feature to work; perf-record does this. Signed-off-by: Jiri Olsa <jolsa@kernel.org> [peterz: small edits to Changelog] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrew Vagin <avagin@openvz.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: e6dab5ffab59 ("perf/trace: Add ability to set a target task for events") Link: http://lkml.kernel.org/r/20180923161343.GB15054@krava Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-02perf/core: Fix perf_pmu_unregister() lockingPeter Zijlstra
When we unregister a PMU, we fail to serialize the @pmu_idr properly. Fix that by doing the entire thing under pmu_lock. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: 2e80a82a49c4 ("perf: Dynamic pmu types") Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-28perf/core: Add sanity check to deal with pinned event failureReinette Chatre
It is possible that a failure can occur during the scheduling of a pinned event. The initial portion of perf_event_read_local() contains the various error checks an event should pass before it can be considered valid. Ensure that the potential scheduling failure of a pinned event is checked for and have a credible error. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: fenghua.yu@intel.com Cc: tony.luck@intel.com Cc: acme@kernel.org Cc: gavin.hindman@intel.com Cc: jithu.joseph@intel.com Cc: dave.hansen@intel.com Cc: hpa@zytor.com Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/6486385d1f30336e9973b24c8c65f5079543d3d3.1537377064.git.reinette.chatre@intel.com
2018-09-10perf/core: Force USER_DS when recording user stack dataYabin Cui
Perf can record user stack data in response to a synchronous request, such as a tracepoint firing. If this happens under set_fs(KERNEL_DS), then we end up reading user stack data using __copy_from_user_inatomic() under set_fs(KERNEL_DS). I think this conflicts with the intention of using set_fs(KERNEL_DS). And it is explicitly forbidden by hardware on ARM64 when both CONFIG_ARM64_UAO and CONFIG_ARM64_PAN are used. So fix this by forcing USER_DS when recording user stack data. Signed-off-by: Yabin Cui <yabinc@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 88b0193d9418 ("perf/callchain: Force USER_DS when invoking perf_callchain_user()") Link: http://lkml.kernel.org/r/20180823225935.27035-1-yabinc@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-09Merge tag 'perf-urgent-for-mingo-4.19-20180903' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent Pull perf/urgent fixes from Arnaldo Carvalho de Melo: Kernel: - Modify breakpoint fixes (Jiri Olsa) perf annotate: - Fix parsing aarch64 branch instructions after objdump update (Kim Phillips) - Fix parsing indirect calls in 'perf annotate' (Martin Liška) perf probe: - Ignore SyS symbols irrespective of endianness on PowerPC (Sandipan Das) perf trace: - Fix include path for asm-generic/unistd.h on arm64 (Kim Phillips) Core libraries: - Fix potential null pointer dereference in perf_evsel__new_idx() (Hisao Tanabe) - Use fixed size string for comms instead of scanf("%m"), that is not present in the bionic libc and leads to a crash (Chris Phlipot) - Fix bad memory access in trace info on 32-bit systems, we were reading 8 bytes from a 4-byte long variable when saving the command line in the perf.data file. (Chris Phlipot) Build system: - Streamline bpf examples and headers installation, clarifying some install messages. (Arnaldo Carvalho de Melo) Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-08-30perf/hw_breakpoint: Simplify breakpoint enable in perf_event_modify_breakpointJiri Olsa
We can safely enable the breakpoint back for both the fail and success paths by checking only the bp->attr.disabled, which either holds the new 'requested' disabled state or the original breakpoint state. Committer testing: At the end of the series, the 'perf test' entry introduced as the first patch now runs to completion without finding the fixed issues: # perf test "bp modify" 62: x86 bp modify : Ok # In verbose mode: # perf test -v "bp modify" 62: x86 bp modify : --- start --- test child forked, pid 5161 rip 5950a0, bp_1 0x5950a0 in bp_1 rip 5950a0, bp_1 0x5950a0 in bp_1 test child finished with 0 ---- end ---- x86 bp modify: Ok Suggested-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Milind Chabbi <chabbi.milind@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20180827091228.2878-6-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-08-21Merge branch 'siginfo-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull core signal handling updates from Eric Biederman: "It was observed that a periodic timer in combination with a sufficiently expensive fork could prevent fork from every completing. This contains the changes to remove the need for that restart. This set of changes is split into several parts: - The first part makes PIDTYPE_TGID a proper pid type instead something only for very special cases. The part starts using PIDTYPE_TGID enough so that in __send_signal where signals are actually delivered we know if the signal is being sent to a a group of processes or just a single process. - With that prep work out of the way the logic in fork is modified so that fork logically makes signals received while it is running appear to be received after the fork completes" * 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (22 commits) signal: Don't send signals to tasks that don't exist signal: Don't restart fork when signals come in. fork: Have new threads join on-going signal group stops fork: Skip setting TIF_SIGPENDING in ptrace_init_task signal: Add calculate_sigpending() fork: Unconditionally exit if a fatal signal is pending fork: Move and describe why the code examines PIDNS_ADDING signal: Push pid type down into complete_signal. signal: Push pid type down into __send_signal signal: Push pid type down into send_signal signal: Pass pid type into do_send_sig_info signal: Pass pid type into send_sigio_to_task & send_sigurg_to_task signal: Pass pid type into group_send_sig_info signal: Pass pid and pid type into send_sigqueue posix-timers: Noralize good_sigevent signal: Use PIDTYPE_TGID to clearly store where file signals will be sent pid: Implement PIDTYPE_TGID pids: Move the pgrp and session pid pointers from task_struct to signal_struct kvm: Don't open code task_pid in kvm_vcpu_ioctl pids: Compute task_tgid using signal->leader_pid ...
2018-08-14Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "A bunch of good stuff in here. Worth noting is that we've pulled in the x86/mm branch from -tip so that we can make use of the core ioremap changes which allow us to put down huge mappings in the vmalloc area without screwing up the TLB. Much of the positive diffstat is because of the rseq selftest for arm64. Summary: - Wire up support for qspinlock, replacing our trusty ticket lock code - Add an IPI to flush_icache_range() to ensure that stale instructions fetched into the pipeline are discarded along with the I-cache lines - Support for the GCC "stackleak" plugin - Support for restartable sequences, plus an arm64 port for the selftest - Kexec/kdump support on systems booting with ACPI - Rewrite of our syscall entry code in C, which allows us to zero the GPRs on entry from userspace - Support for chained PMU counters, allowing 64-bit event counters to be constructed on current CPUs - Ensure scheduler topology information is kept up-to-date with CPU hotplug events - Re-enable support for huge vmalloc/IO mappings now that the core code has the correct hooks to use break-before-make sequences - Miscellaneous, non-critical fixes and cleanups" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (90 commits) arm64: alternative: Use true and false for boolean values arm64: kexec: Add comment to explain use of __flush_icache_range() arm64: sdei: Mark sdei stack helper functions as static arm64, kaslr: export offset in VMCOREINFO ELF notes arm64: perf: Add cap_user_time aarch64 efi/libstub: Only disable stackleak plugin for arm64 arm64: drop unused kernel_neon_begin_partial() macro arm64: kexec: machine_kexec should call __flush_icache_range arm64: svc: Ensure hardirq tracing is updated before return arm64: mm: Export __sync_icache_dcache() for xen-privcmd drivers/perf: arm-ccn: Use devm_ioremap_resource() to map memory arm64: Add support for STACKLEAK gcc plugin arm64: Add stack information to on_accessible_stack drivers/perf: hisi: update the sccl_id/ccl_id when MT is supported arm64: fix ACPI dependencies rseq/selftests: Add support for arm64 arm64: acpi: fix alignment fault in accessing ACPI efi/arm: map UEFI memory map even w/o runtime services enabled efi/arm: preserve early mapping of UEFI memory map longer for BGRT drivers: acpi: add dependency of EFI for arm64 ...
2018-07-31arm64: perf: Add cap_user_time aarch64Michael O'Farrell
It is useful to get the running time of a thread. Doing so in an efficient manner can be important for performance of user applications. Avoiding system calls in `clock_gettime` when handling CLOCK_THREAD_CPUTIME_ID is important. Other clocks are handled in the VDSO, but CLOCK_THREAD_CPUTIME_ID falls back on the system call. CLOCK_THREAD_CPUTIME_ID is not handled in the VDSO since it would have costs associated with maintaining updated user space accessible time offsets. These offsets have to be updated everytime the a thread is scheduled/descheduled. However, for programs regularly checking the running time of a thread, this is a performance improvement. This patch takes a middle ground, and adds support for cap_user_time an optional feature of the perf_event API. This way costs are only incurred when the perf_event api is enabled. This is done the same way as it is in x86. Ultimately this allows calculating the thread running time in userspace on aarch64 as follows (adapted from perf_event_open manpage): u32 seq, time_mult, time_shift; u64 running, count, time_offset, quot, rem, delta; struct perf_event_mmap_page *pc; pc = buf; // buf is the perf event mmaped page as documented in the API. if (pc->cap_usr_time) { do { seq = pc->lock; barrier(); running = pc->time_running; count = readCNTVCT_EL0(); // Read ARM hardware clock. time_offset = pc->time_offset; time_mult = pc->time_mult; time_shift = pc->time_shift; barrier(); } while (pc->lock != seq); quot = (count >> time_shift); rem = count & (((u64)1 << time_shift) - 1); delta = time_offset + quot * time_mult + ((rem * time_mult) >> time_shift); running += delta; // running now has the current nanosecond level thread time. } Summary of changes in the patch: For aarch64 systems, make arch_perf_update_userpage update the timing information stored in the perf_event page. Requiring the following calculations: - Calculate the appropriate time_mult, and time_shift factors to convert ticks to nano seconds for the current clock frequency. - Adjust the mult and shift factors to avoid shift factors of 32 bits. (possibly unnecessary) - The time_offset userspace should apply when doing calculations: negative the current sched time (now), because time_running and time_enabled fields of the perf_event page have just been updated. Toggle bits to appropriate values: - Enable cap_user_time Signed-off-by: Michael O'Farrell <micpof@gmail.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-25Merge branch 'perf/urgent' into perf/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25perf/core: Fix crash when using HW tracing kernel filtersMathieu Poirier
In function perf_event_parse_addr_filter(), the path::dentry of each struct perf_addr_filter is left unassigned (as it should be) when the pattern being parsed is related to kernel space. But in function perf_addr_filter_match() the same dentries are given to d_inode() where the value is not expected to be NULL, resulting in the following splat: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000058 pc : perf_event_mmap+0x2fc/0x5a0 lr : perf_event_mmap+0x2c8/0x5a0 Process uname (pid: 2860, stack limit = 0x000000001cbcca37) Call trace: perf_event_mmap+0x2fc/0x5a0 mmap_region+0x124/0x570 do_mmap+0x344/0x4f8 vm_mmap_pgoff+0xe4/0x110 vm_mmap+0x2c/0x40 elf_map+0x60/0x108 load_elf_binary+0x450/0x12c4 search_binary_handler+0x90/0x290 __do_execve_file.isra.13+0x6e4/0x858 sys_execve+0x3c/0x50 el0_svc_naked+0x30/0x34 This patch is fixing the problem by introducing a new check in function perf_addr_filter_match() to see if the filter's dentry is NULL. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: acme@kernel.org Cc: miklos@szeredi.hu Cc: namhyung@kernel.org Cc: songliubraving@fb.com Fixes: 9511bce9fe8e ("perf/core: Fix bad use of igrab()") Link: http://lkml.kernel.org/r/1531782831-1186-1-git-send-email-mathieu.poirier@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25perf/x86/intel: Fix unwind errors from PEBS entries (mk-II)Peter Zijlstra
Vince reported the perf_fuzzer giving various unwinder warnings and Josh reported: > Deja vu. Most of these are related to perf PEBS, similar to the > following issue: > > b8000586c90b ("perf/x86/intel: Cure bogus unwind from PEBS entries") > > This is basically the ORC version of that. setup_pebs_sample_data() is > assembling a franken-pt_regs which ORC isn't happy about. RIP is > inconsistent with some of the other registers (like RSP and RBP). And where the previous unwinder only needed BP,SP ORC also requires IP. But we cannot spoof IP because then the sample will get displaced, entirely negating the point of PEBS. So cure the whole thing differently by doing the unwind early; this does however require a means to communicate we did the unwind early. We (ab)use an unused sample_type bit for this, which we set on events that fill out the data->callchain before the normal perf_prepare_sample(). Debugged-by: Josh Poimboeuf <jpoimboe@redhat.com> Reported-by: Vince Weaver <vincent.weaver@maine.edu> Tested-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-21pid: Implement PIDTYPE_TGIDEric W. Biederman
Everywhere except in the pid array we distinguish between a tasks pid and a tasks tgid (thread group id). Even in the enumeration we want that distinction sometimes so we have added __PIDTYPE_TGID. With leader_pid we almost have an implementation of PIDTYPE_TGID in struct signal_struct. Add PIDTYPE_TGID as a first class member of the pid_type enumeration and into the pids array. Then remove the __PIDTYPE_TGID special case and the leader_pid in signal_struct. The net size increase is just an extra pointer added to struct pid and an extra pair of pointers of an hlist_node added to task_struct. The effect on code maintenance is the removal of a number of special cases today and the potential to remove many more special cases as PIDTYPE_TGID gets used to it's fullest. The long term potential is allowing zombie thread group leaders to exit, which will remove a lot more special cases in the code. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-07-16perf, tools: Use correct articles in commentsTobias Tefke
Some of the comments in the perf events code use articles incorrectly, using 'a' for words beginning with a vowel sound, where 'an' should be used. Signed-off-by: Tobias Tefke <tobias.tefke@tutanota.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: acme@kernel.org Cc: alexander.shishkin@linux.intel.com Cc: jolsa@redhat.com Cc: namhyung@kernel.org Link: http://lkml.kernel.org/r/20180709105715.22938-1-tobias.tefke@tutanota.com [ Fix a few more perf related 'a event' typo fixes from all around the kernel and tooling tree. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-27perf/core: Move inline keyword at the beginning of declarationMathieu Malaterre
Fix non-fatal warning triggered during compilation with W=1: kernel/events/core.c:6106:1: warning: ‘inline’ is not at beginning of declaration [-Wold-style-declaration] static void __always_inline ^~~~~~ Signed-off-by: Mathieu Malaterre <malat@debian.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180626202301.20270-1-malat@debian.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-21perf/core: Change perf_mmap_fault() return type to 'vm_fault_t'Souptick Joarder
Use new return type 'vm_fault_t' for fault handlers. For now, this is just documenting that the function returns a VM_FAULT value rather than an errno. Once all instances are converted, vm_fault_t will become a distinct type. See the following commit: 1c8f422059ae ("mm: change return type to vm_fault_t") Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com> Acked-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: acme@kernel.org Cc: akpm@linux-foundation.org Cc: alexander.shishkin@linux.intel.com Cc: jolsa@redhat.com Cc: namhyung@kernel.org Link: https://lkml.kernel.org/lkml/20180521182520.GA19677@jordon-HP-15-Notebook-PC Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds
Pull networking updates from David Miller: 1) Add Maglev hashing scheduler to IPVS, from Inju Song. 2) Lots of new TC subsystem tests from Roman Mashak. 3) Add TCP zero copy receive and fix delayed acks and autotuning with SO_RCVLOWAT, from Eric Dumazet. 4) Add XDP_REDIRECT support to mlx5 driver, from Jesper Dangaard Brouer. 5) Add ttl inherit support to vxlan, from Hangbin Liu. 6) Properly separate ipv6 routes into their logically independant components. fib6_info for the routing table, and fib6_nh for sets of nexthops, which thus can be shared. From David Ahern. 7) Add bpf_xdp_adjust_tail helper, which can be used to generate ICMP messages from XDP programs. From Nikita V. Shirokov. 8) Lots of long overdue cleanups to the r8169 driver, from Heiner Kallweit. 9) Add BTF ("BPF Type Format"), from Martin KaFai Lau. 10) Add traffic condition monitoring to iwlwifi, from Luca Coelho. 11) Plumb extack down into fib_rules, from Roopa Prabhu. 12) Add Flower classifier offload support to igb, from Vinicius Costa Gomes. 13) Add UDP GSO support, from Willem de Bruijn. 14) Add documentation for eBPF helpers, from Quentin Monnet. 15) Add TLS tx offload to mlx5, from Ilya Lesokhin. 16) Allow applications to be given the number of bytes available to read on a socket via a control message returned from recvmsg(), from Soheil Hassas Yeganeh. 17) Add x86_32 eBPF JIT compiler, from Wang YanQing. 18) Add AF_XDP sockets, with zerocopy support infrastructure as well. From Björn Töpel. 19) Remove indirect load support from all of the BPF JITs and handle these operations in the verifier by translating them into native BPF instead. From Daniel Borkmann. 20) Add GRO support to ipv6 gre tunnels, from Eran Ben Elisha. 21) Allow XDP programs to do lookups in the main kernel routing tables for forwarding. From David Ahern. 22) Allow drivers to store hardware state into an ELF section of kernel dump vmcore files, and use it in cxgb4. From Rahul Lakkireddy. 23) Various RACK and loss detection improvements in TCP, from Yuchung Cheng. 24) Add TCP SACK compression, from Eric Dumazet. 25) Add User Mode Helper support and basic bpfilter infrastructure, from Alexei Starovoitov. 26) Support ports and protocol values in RTM_GETROUTE, from Roopa Prabhu. 27) Support bulking in ->ndo_xdp_xmit() API, from Jesper Dangaard Brouer. 28) Add lots of forwarding selftests, from Petr Machata. 29) Add generic network device failover driver, from Sridhar Samudrala. * ra.kernel.org:/pub/scm/linux/kernel/git/davem/net-next: (1959 commits) strparser: Add __strp_unpause and use it in ktls. rxrpc: Fix terminal retransmission connection ID to include the channel net: hns3: Optimize PF CMDQ interrupt switching process net: hns3: Fix for VF mailbox receiving unknown message net: hns3: Fix for VF mailbox cannot receiving PF response bnx2x: use the right constant Revert "net: sched: cls: Fix offloading when ingress dev is vxlan" net: dsa: b53: Fix for brcm tag issue in Cygnus SoC enic: fix UDP rss bits netdev-FAQ: clarify DaveM's position for stable backports rtnetlink: validate attributes in do_setlink() mlxsw: Add extack messages for port_{un, }split failures netdevsim: Add extack error message for devlink reload devlink: Add extack to reload and port_{un, }split operations net: metrics: add proper netlink validation ipmr: fix error path when ipmr_new_table fails ip6mr: only set ip6mr_table from setsockopt when ip6mr_new_table succeeds net: hns3: remove unused hclgevf_cfg_func_mta_filter netfilter: provide udp*_lib_lookup for nf_tproxy qed*: Utilize FW 8.37.2.0 ...
2018-05-25perf/core: Wire up compat PERF_EVENT_IOC_QUERY_BPF, ↵Eugene Syromiatnikov
PERF_EVENT_IOC_MODIFY_ATTRIBUTES Since pointer size is different in compat, and switching in _perf_ioctl is done using exact ioctl numbers, all new ioctl numbers that use pointer should be added to perf_compat_ioctl for _IOC_SIZE fixup before passing to perf_ioctl routine (this shouldn't be needed if semantics of the size argument of _IO* macros was honored). Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/20180521123420.GA24291@asgard.redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-25perf/core: Fix bad use of igrab()Song Liu
As Miklos reported and suggested: "This pattern repeats two times in trace_uprobe.c and in kernel/events/core.c as well: ret = kern_path(filename, LOOKUP_FOLLOW, &path); if (ret) goto fail_address_parse; inode = igrab(d_inode(path.dentry)); path_put(&path); And it's wrong. You can only hold a reference to the inode if you have an active ref to the superblock as well (which is normally through path.mnt) or holding s_umount. This way unmounting the containing filesystem while the tracepoint is active will give you the "VFS: Busy inodes after unmount..." message and a crash when the inode is finally put. Solution: store path instead of inode." This patch fixes the issue in kernel/event/core.c. Reviewed-and-tested-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Reported-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <kernel-team@fb.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: 375637bc5249 ("perf/core: Introduce address range filtering") Link: http://lkml.kernel.org/r/20180418062907.3210386-2-songliubraving@fb.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-25perf/core: Fix group scheduling with mixed hw and sw eventsSong Liu
When hw and sw events are mixed in the same group, they are all attached to the hw perf_event_context. This sometimes requires moving group of perf_event to a different context. We found a bug in how the kernel handles this, for example if we do: perf stat -e '{faults,ref-cycles,faults}' -I 1000 1.005591180 1,297 faults 1.005591180 457,476,576 ref-cycles 1.005591180 <not supported> faults First, sw event "faults" is attached to the sw context, and becomes the group leader. Then, hw event "ref-cycles" is attached, so both events are moved to the hw context. Last, another sw "faults" tries to attach, but it fails because of mismatch between the new target ctx (from sw pmu) and the group_leader's ctx (hw context, same as ref-cycles). The broken condition is: group_leader is sw event; group_leader is on hw context; add a sw event to the group. Fix this scenario by checking group_leader's context (instead of just event type). If group_leader is on hw context, use the ->pmu of this context to look up context for the new event. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <kernel-team@fb.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: b04243ef7006 ("perf: Complete software pmu grouping") Link: http://lkml.kernel.org/r/20180503194716.162815-1-songliubraving@fb.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-24perf/core: add perf_get_event() to return perf_event given a struct fileYonghong Song
A new extern function, perf_get_event(), is added to return a perf event given a struct file. This function will be used in later patches. Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-04-17perf: Return proper values for user stack errorsJiri Olsa
Return immediately when we find issue in the user stack checks. The error value could get overwritten by following check for PERF_SAMPLE_REGS_INTR. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: syzkaller-bugs@googlegroups.com Cc: x86@kernel.org Fixes: 60e2364e60e8 ("perf: Add ability to sample machine state on interrupt") Link: http://lkml.kernel.org/r/20180415092352.12403-1-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-04-17perf/core: Store context switch out type in PERF_RECORD_SWITCH[_CPU_WIDE]Alexey Budankov
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 <alexey.budankov@linux.intel.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Link: http://lkml.kernel.org/r/9ff84e83-a0ca-dd82-a6d0-cb951689be74@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-04-12perf/core: Need CAP_SYS_ADMIN to create k/uprobe with perf_event_open()Song Liu
Non-root user cannot create kprobe or uprobe through the text-based interface (kprobe_events, uprobe_events),so they should not be able to create probes via perf_event_open() either. Reported-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Song Liu <songliubraving@fb.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 33ea4b24277b ("perf/core: Implement the 'perf_uprobe' PMU") Fixes: e12f03d7031a ("perf/core: Implement the 'perf_kprobe' PMU") Link: http://lkml.kernel.org/r/C0B2EFB5-C403-4BDB-9046-C14B3EE66999@fb.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-09perf/core: Fix use-after-free in uprobe_perf_close()Prashant Bhole
A use-after-free bug was caught by KASAN while running usdt related code (BCC project. bcc/tests/python/test_usdt2.py): ================================================================== BUG: KASAN: use-after-free in uprobe_perf_close+0x222/0x3b0 Read of size 4 at addr ffff880384f9b4a4 by task test_usdt2.py/870 CPU: 4 PID: 870 Comm: test_usdt2.py Tainted: G W 4.16.0-next-20180409 #215 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014 Call Trace: dump_stack+0xc7/0x15b ? show_regs_print_info+0x5/0x5 ? printk+0x9c/0xc3 ? kmsg_dump_rewind_nolock+0x6e/0x6e ? uprobe_perf_close+0x222/0x3b0 print_address_description+0x83/0x3a0 ? uprobe_perf_close+0x222/0x3b0 kasan_report+0x1dd/0x460 ? uprobe_perf_close+0x222/0x3b0 uprobe_perf_close+0x222/0x3b0 ? probes_open+0x180/0x180 ? free_filters_list+0x290/0x290 trace_uprobe_register+0x1bb/0x500 ? perf_event_attach_bpf_prog+0x310/0x310 ? probe_event_disable+0x4e0/0x4e0 perf_uprobe_destroy+0x63/0xd0 _free_event+0x2bc/0xbd0 ? lockdep_rcu_suspicious+0x100/0x100 ? ring_buffer_attach+0x550/0x550 ? kvm_sched_clock_read+0x1a/0x30 ? perf_event_release_kernel+0x3e4/0xc00 ? __mutex_unlock_slowpath+0x12e/0x540 ? wait_for_completion+0x430/0x430 ? lock_downgrade+0x3c0/0x3c0 ? lock_release+0x980/0x980 ? do_raw_spin_trylock+0x118/0x150 ? do_raw_spin_unlock+0x121/0x210 ? do_raw_spin_trylock+0x150/0x150 perf_event_release_kernel+0x5d4/0xc00 ? put_event+0x30/0x30 ? fsnotify+0xd2d/0xea0 ? sched_clock_cpu+0x18/0x1a0 ? __fsnotify_update_child_dentry_flags.part.0+0x1b0/0x1b0 ? pvclock_clocksource_read+0x152/0x2b0 ? pvclock_read_flags+0x80/0x80 ? kvm_sched_clock_read+0x1a/0x30 ? sched_clock_cpu+0x18/0x1a0 ? pvclock_clocksource_read+0x152/0x2b0 ? locks_remove_file+0xec/0x470 ? pvclock_read_flags+0x80/0x80 ? fcntl_setlk+0x880/0x880 ? ima_file_free+0x8d/0x390 ? lockdep_rcu_suspicious+0x100/0x100 ? ima_file_check+0x110/0x110 ? fsnotify+0xea0/0xea0 ? kvm_sched_clock_read+0x1a/0x30 ? rcu_note_context_switch+0x600/0x600 perf_release+0x21/0x40 __fput+0x264/0x620 ? fput+0xf0/0xf0 ? do_raw_spin_unlock+0x121/0x210 ? do_raw_spin_trylock+0x150/0x150 ? SyS_fchdir+0x100/0x100 ? fsnotify+0xea0/0xea0 task_work_run+0x14b/0x1e0 ? task_work_cancel+0x1c0/0x1c0 ? copy_fd_bitmaps+0x150/0x150 ? vfs_read+0xe5/0x260 exit_to_usermode_loop+0x17b/0x1b0 ? trace_event_raw_event_sys_exit+0x1a0/0x1a0 do_syscall_64+0x3f6/0x490 ? syscall_return_slowpath+0x2c0/0x2c0 ? lockdep_sys_exit+0x1f/0xaa ? syscall_return_slowpath+0x1a3/0x2c0 ? lockdep_sys_exit+0x1f/0xaa ? prepare_exit_to_usermode+0x11c/0x1e0 ? enter_from_user_mode+0x30/0x30 random: crng init done ? __put_user_4+0x1c/0x30 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x7f41d95f9340 RSP: 002b:00007fffe71e4268 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 000000000000000d RCX: 00007f41d95f9340 RDX: 0000000000000000 RSI: 0000000000002401 RDI: 000000000000000d RBP: 0000000000000000 R08: 00007f41ca8ff700 R09: 00007f41d996dd1f R10: 00007fffe71e41e0 R11: 0000000000000246 R12: 00007fffe71e4330 R13: 0000000000000000 R14: fffffffffffffffc R15: 00007fffe71e4290 Allocated by task 870: kasan_kmalloc+0xa0/0xd0 kmem_cache_alloc_node+0x11a/0x430 copy_process.part.19+0x11a0/0x41c0 _do_fork+0x1be/0xa20 do_syscall_64+0x198/0x490 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 Freed by task 0: __kasan_slab_free+0x12e/0x180 kmem_cache_free+0x102/0x4d0 free_task+0xfe/0x160 __put_task_struct+0x189/0x290 delayed_put_task_struct+0x119/0x250 rcu_process_callbacks+0xa6c/0x1b60 __do_softirq+0x238/0x7ae The buggy address belongs to the object at ffff880384f9b480 which belongs to the cache task_struct of size 12928 It occurs because task_struct is freed before perf_event which refers to the task and task flags are checked while teardown of the event. perf_event_alloc() assigns task_struct to hw.target of perf_event, but there is no reference counting for it. As a fix we get_task_struct() in perf_event_alloc() at above mentioned assignment and put_task_struct() in _free_event(). Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 63b6da39bb38e8f1a1ef3180d32a39d6 ("perf: Fix perf_event_exit_task() race") Link: http://lkml.kernel.org/r/20180409100346.6416-1-bhole_prashant_q7@lab.ntt.co.jp Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-29perf/x86/pt, coresight: Clean up address filter structureAlexander Shishkin
This is a cosmetic patch that deals with the address filter structure's ambiguous fields 'filter' and 'range'. The former stands to mean that the filter's *action* should be to filter the traces to its address range if it's set or stop tracing if it's unset. This is confusing and hard on the eyes, so this patch replaces it with 'action' enum. The 'range' field is completely redundant (meaning that the filter is an address range as opposed to a single address trigger), as we can use zero size to mean the same thing. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Will Deacon <will.deacon@arm.com> Link: http://lkml.kernel.org/r/20180329120648.11902-1-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-24Merge branch 'perf/urgent' into perf/core, to pick up fixesIngo Molnar
With the cherry-picked perf/urgent commit merged separately we can now merge all the fixes without conflicts. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-20perf/cgroup: Fix child event counting bugSong Liu
When a perf_event is attached to parent cgroup, it should count events for all children cgroups: parent_group <---- perf_event \ - child_group <---- process(es) However, in our tests, we found this perf_event cannot report reliable results. Here is an example case: # create cgroups mkdir -p /sys/fs/cgroup/p/c # start perf for parent group perf stat -e instructions -G "p" # on another console, run test process in child cgroup: stressapptest -s 2 -M 1000 & echo $! > /sys/fs/cgroup/p/c/cgroup.procs # after the test process is done, stop perf in the first console shows <not counted> instructions p The instruction should not be "not counted" as the process runs in the child cgroup. We found this is because perf_event->cgrp and cpuctx->cgrp are not identical, thus perf_event->cgrp are not updated properly. This patch fixes this by updating perf_cgroup properly for ancestor cgroup(s). Reported-by: Ephraim Park <ephiepark@fb.com> Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <jolsa@redhat.com> Cc: <kernel-team@fb.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/20180312165943.1057894-1-songliubraving@fb.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-19Merge tag 'v4.16-rc6' into perf/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-16perf/core: Clear sibling list of detached eventsMark Rutland
When perf_group_dettach() is called on a group leader, it updates each sibling's group_leader field to point to that sibling, effectively upgrading each siblnig to a group leader. After perf_group_detach has completed, the caller may free the leader event. We only remove siblings from the group leader's sibling_list when the leader has a non-empty group_node. This was fine prior to commit: 8343aae66167df67 ("perf/core: Remove perf_event::group_entry") ... as the sibling's sibling_list would be empty. However, now that we use the sibling_list field as both the list head and the list entry, this leaves each sibling with a non-empty sibling list, including the stale leader event. If perf_group_detach() is subsequently called on a sibling, it will appear to be a group leader, and we'll walk the sibling_list, potentially dereferencing these stale events. In 0day testing, this has been observed to result in kernel panics. Let's avoid this by always removing siblings from the sibling list when we promote them to leaders. Fixes: 8343aae66167df67 ("perf/core: Remove perf_event::group_entry") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: vincent.weaver@maine.edu Cc: Peter Zijlstra <peterz@infradead.org> Cc: torvalds@linux-foundation.org Cc: Alexey Budankov <alexey.budankov@linux.intel.com> Cc: valery.cherepennikov@intel.com Cc: linux-tip-commits@vger.kernel.org Cc: eranian@google.com Cc: acme@redhat.com Cc: alexander.shishkin@linux.intel.com Cc: davidcc@google.com Cc: kan.liang@intel.com Cc: Dmitry.Prohorov@intel.com Cc: Jiri Olsa <jolsa@redhat.com> Link: https://lkml.kernel.org/r/20180316131741.3svgr64yibc6vsid@lakrids.cambridge.arm.com
2018-03-16perf: Fix sibling iterationPeter Zijlstra
Mark noticed that the change to sibling_list changed some iteration semantics; because previously we used group_list as list entry, sibling events would always have an empty sibling_list. But because we now use sibling_list for both list head and list entry, siblings will report as having siblings. Fix this with a custom for_each_sibling_event() iterator. Fixes: 8343aae66167 ("perf/core: Remove perf_event::group_entry") Reported-by: Mark Rutland <mark.rutland@arm.com> Suggested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: vincent.weaver@maine.edu Cc: alexander.shishkin@linux.intel.com Cc: torvalds@linux-foundation.org Cc: alexey.budankov@linux.intel.com Cc: valery.cherepennikov@intel.com Cc: eranian@google.com Cc: acme@redhat.com Cc: linux-tip-commits@vger.kernel.org Cc: davidcc@google.com Cc: kan.liang@intel.com Cc: Dmitry.Prohorov@intel.com Cc: jolsa@redhat.com Link: https://lkml.kernel.org/r/20180315170129.GX4043@hirez.programming.kicks-ass.net
2018-03-13perf/core: Implement fast breakpoint modification via _IOC_MODIFY_ATTRIBUTESMilind Chabbi
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 <chabbi.milind@gmail.com> [ Using modify_user_hw_breakpoint_check function. ] [ Reformated PERF_EVENT_IOC_*, so the values are all in one column. ] Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Hari Bathini <hbathini@linux.vnet.ibm.com> Cc: Jin Yao <yao.jin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Oleg Nesterov <onestero@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: http://lkml.kernel.org/r/20180312134548.31532-8-jolsa@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-13perf/core: Move perf_event_attr::sample_max_stack into perf_copy_attr()Jiri Olsa
Move the sample_max_stack check and setup into perf_copy_attr(), so we have all perf_event_attr initial setup in one place and can easily compare attrs in the new ioctl introduced in following change. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Hari Bathini <hbathini@linux.vnet.ibm.com> Cc: Jin Yao <yao.jin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Milind Chabbi <chabbi.milind@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Oleg Nesterov <onestero@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: http://lkml.kernel.org/r/20180312134548.31532-7-jolsa@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12perf/core: Fix installing cgroup events on CPUleilei.lin
There's two problems when installing cgroup events on CPUs: firstly list_update_cgroup_event() only tries to set cpuctx->cgrp for the first event, if that mismatches on @cgrp we'll not try again for later additions. Secondly, when we install a cgroup event into an active context, only issue an event reprogram when the event matches the current cgroup context. This avoids a pointless event reprogramming. Signed-off-by: leilei.lin <leilei.lin@alibaba-inc.com> [ Improved the changelog and comments. ] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: brendan.d.gregg@gmail.com Cc: eranian@gmail.com Cc: linux-kernel@vger.kernel.org Cc: yang_oliver@hotmail.com Link: http://lkml.kernel.org/r/20180306093637.28247-1-linxiulei@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12perf/core: Optimize perf_rotate_context() event schedulingPeter Zijlstra
The event schedule order (as per perf_event_sched_in()) is: - cpu pinned - task pinned - cpu flexible - task flexible But perf_rotate_context() will unschedule cpu-flexible even if it doesn't need a rotation. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12perf/core: Fix tree based event rotationPeter Zijlstra
Similar to how first programming cpu=-1 and then cpu=# is wrong, so is rotating both. It was especially wrong when we were still programming the PMU in this same order, because in that scenario we might never actually end up running cpu=# events at all. Cure this by using the active_list to pick the rotation event; since at programming we already select the left-most event. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexey Budankov <alexey.budankov@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Carrillo-Cisneros <davidcc@google.com> Cc: Dmitri Prokhorov <Dmitry.Prohorov@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Valery Cherepennikov <valery.cherepennikov@intel.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12perf/core: Simpify perf_event_groups_for_each()Peter Zijlstra
The last argument is, and always must be, the same. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexey Budankov <alexey.budankov@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Carrillo-Cisneros <davidcc@google.com> Cc: Dmitri Prokhorov <Dmitry.Prohorov@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Valery Cherepennikov <valery.cherepennikov@intel.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12perf/core: Optimize ctx_sched_out()Peter Zijlstra
When an event group contains more events than can be scheduled on the hardware, iterating the full event group for ctx_sched_out is a waste of time. Keep track of the events that got programmed on the hardware, such that we can iterate this smaller list in order to schedule them out. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexey Budankov <alexey.budankov@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Carrillo-Cisneros <davidcc@google.com> Cc: Dmitri Prokhorov <Dmitry.Prohorov@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Valery Cherepennikov <valery.cherepennikov@intel.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12perf/core: Remove perf_event::group_entryPeter Zijlstra
Now that all the grouping is done with RB trees, we no longer need group_entry and can replace the whole thing with sibling_list. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexey Budankov <alexey.budankov@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Carrillo-Cisneros <davidcc@google.com> Cc: Dmitri Prokhorov <Dmitry.Prohorov@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Valery Cherepennikov <valery.cherepennikov@intel.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12perf/core: Fix event schedule orderPeter Zijlstra
Scheduling in events with cpu=-1 before events with cpu=# changes semantics and is undesirable in that it would priorize these events. Given that groups->index is across all groups we actually have an inter-group ordering, meaning we can merge-sort two groups, which is just what we need to preserve semantics. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexey Budankov <alexey.budankov@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Carrillo-Cisneros <davidcc@google.com> Cc: Dmitri Prokhorov <Dmitry.Prohorov@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Valery Cherepennikov <valery.cherepennikov@intel.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12perf/core: Cleanup the rb-tree codePeter Zijlstra
Trivial comment and code fixups.. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexey Budankov <alexey.budankov@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Carrillo-Cisneros <davidcc@google.com> Cc: Dmitri Prokhorov <Dmitry.Prohorov@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Valery Cherepennikov <valery.cherepennikov@intel.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12perf/cor: Use RB trees for pinned/flexible groupsAlexey Budankov
Change event groups into RB trees sorted by CPU and then by a 64bit index, so that multiplexing hrtimer interrupt handler would be able skipping to the current CPU's list and ignore groups allocated for the other CPUs. New API for manipulating event groups in the trees is implemented as well as adoption on the API in the current implementation. pinned_group_sched_in() and flexible_group_sched_in() API are introduced to consolidate code enabling the whole group from pinned and flexible groups appropriately. Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: David Carrillo-Cisneros <davidcc@google.com> Cc: Dmitri Prokhorov <Dmitry.Prohorov@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Valery Cherepennikov <valery.cherepennikov@intel.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/372f9c8b-0cfe-4240-e44d-83d863d40813@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12perf/core: Fix perf_output_read_group()Peter Zijlstra
Mark reported his arm64 perf fuzzer runs sometimes splat like: armv8pmu_read_counter+0x1e8/0x2d8 armpmu_event_update+0x8c/0x188 armpmu_read+0xc/0x18 perf_output_read+0x550/0x11e8 perf_event_read_event+0x1d0/0x248 perf_event_exit_task+0x468/0xbb8 do_exit+0x690/0x1310 do_group_exit+0xd0/0x2b0 get_signal+0x2e8/0x17a8 do_signal+0x144/0x4f8 do_notify_resume+0x148/0x1e8 work_pending+0x8/0x14 which asserts that we only call pmu::read() on ACTIVE events. The above callchain does: perf_event_exit_task() perf_event_exit_task_context() task_ctx_sched_out() // INACTIVE perf_event_exit_event() perf_event_set_state(EXIT) // EXIT sync_child_event() perf_event_read_event() perf_output_read() perf_output_read_group() leader->pmu->read() Which results in doing a pmu::read() on an !ACTIVE event. I _think_ this is 'new' since we added attr.inherit_stat, which added the perf_event_read_event() to the exit path, without that perf_event_read_output() would only trigger from samples and for @event to trigger a sample, it's leader _must_ be ACTIVE too. Still, adding this check makes it consistent with the @sub case for the siblings. Reported-and-Tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-09perf/core: Fix ctx_event_type in ctx_resched()Song Liu
In ctx_resched(), EVENT_FLEXIBLE should be sched_out when EVENT_PINNED is added. However, ctx_resched() calculates ctx_event_type before checking this condition. As a result, pinned events will NOT get higher priority than flexible events. The following shows this issue on an Intel CPU (where ref-cycles can only use one hardware counter). 1. First start: perf stat -C 0 -e ref-cycles -I 1000 2. Then, in the second console, run: perf stat -C 0 -e ref-cycles:D -I 1000 The second perf uses pinned events, which is expected to have higher priority. However, because it failed in ctx_resched(). It is never run. This patch fixes this by calculating ctx_event_type after re-evaluating event_type. Reported-by: Ephraim Park <ephiepark@fb.com> Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <jolsa@redhat.com> Cc: <kernel-team@fb.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: 487f05e18aa4 ("perf/core: Optimize event rescheduling on active contexts") Link: http://lkml.kernel.org/r/20180306055504.3283731-1-songliubraving@fb.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-17Merge branch 'perf/urgent' into perf/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-11vfs: do bulk POLL* -> EPOLL* replacementLinus Torvalds
This is the mindless scripted replacement of kernel use of POLL* variables as described by Al, done by this script: for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'` for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done done with de-mangling cleanups yet to come. NOTE! On almost all architectures, the EPOLL* constants have the same values as the POLL* constants do. But they keyword here is "almost". For various bad reasons they aren't the same, and epoll() doesn't actually work quite correctly in some cases due to this on Sparc et al. The next patch from Al will sort out the final differences, and we should be all done. Scripted-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>