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2013-12-17perf: Disable all pmus on unthrottling and reschedulingAlexander Shishkin
Currently, only one PMU in a context gets disabled during unthrottling and event_sched_{out,in}(), however, events in one context may belong to different pmus, which results in PMUs being reprogrammed while they are still enabled. This means that mixed PMU use [which is rare in itself] resulted in potentially completely unreliable results: corrupted events, bogus results, etc. This patch temporarily disables PMUs that correspond to each event in the context while these events are being modified. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Reviewed-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Stephane Eranian <eranian@google.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Link: http://lkml.kernel.org/r/1387196256-8030-1-git-send-email-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-19perf: Remove fragile swevent hlist optimizationPeter Zijlstra
Currently we only allocate a single cpu hashtable for per-cpu swevents; do away with this optimization for it is fragile in the face of things like perf_pmu_migrate_context(). The easiest thing is to make sure all CPUs are consistent wrt state. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20130913111447.GN31370@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-13list: introduce list_next_entry() and list_prev_entry()Oleg Nesterov
Add two trivial helpers list_next_entry() and list_prev_entry(), they can have a lot of users including list.h itself. In fact the 1st one is already defined in events/core.c and bnx2x_sp.c, so the patch simply moves the definition to list.h. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: Eilon Greenstein <eilong@broadcom.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-12Merge branch 'perf-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Ingo Molnar: "As a first remark I'd like to note that the way to build perf tooling has been simplified and sped up, in the future it should be enough for you to build perf via: cd tools/perf/ make install (ie without the -j option.) The build system will figure out the number of CPUs and will do a parallel build+install. The various build system inefficiencies and breakages Linus reported against the v3.12 pull request should now be resolved - please (re-)report any remaining annoyances or bugs. Main changes on the perf kernel side: * Performance optimizations: . perf ring-buffer code optimizations, by Peter Zijlstra . perf ring-buffer code optimizations, by Oleg Nesterov . x86 NMI call-stack processing optimizations, by Peter Zijlstra . perf context-switch optimizations, by Peter Zijlstra . perf sampling speedups, by Peter Zijlstra . x86 Intel PEBS processing speedups, by Peter Zijlstra * Enhanced hardware support: . for Intel Ivy Bridge-EP uncore PMUs, by Zheng Yan . for Haswell transactions, by Andi Kleen, Peter Zijlstra * Core perf events code enhancements and fixes by Oleg Nesterov: . for uprobes, if fork() is called with pending ret-probes . for uprobes platform support code * New ABI details by Andi Kleen: . Report x86 Haswell TSX transaction abort cost as weight Main changes on the perf tooling side (some of these tooling changes utilize the above kernel side changes): * 'perf report/top' enhancements: . Convert callchain children list to rbtree, greatly reducing the time taken for callchain processing, from Namhyung Kim. . Add new COMM infrastructure, further improving histogram processing, from Frédéric Weisbecker, one fix from Namhyung Kim. . Add /proc/kcore based live-annotation improvements, including build-id cache support, multi map 'call' instruction navigation fixes, kcore address validation, objdump workarounds. From Adrian Hunter. . Show progress on histogram collapsing, that can take a long time, from Namhyung Kim. . Add --max-stack option to limit callchain stack scan in 'top' and 'report', improving callchain processing when reducing the stack depth is an option, from Waiman Long. . Add new option --ignore-vmlinux for perf top, from Willy Tarreau. * 'perf trace' enhancements: . 'perf trace' now can can use a 'perf probe' dynamic tracepoints to hook into the userspace -> kernel pathname copy so that it can map fds to pathnames without reading /proc/pid/fd/ symlinks. From Arnaldo Carvalho de Melo. . Show VFS path associated with fd in live sessions, using a 'vfs_getname' 'perf probe' created dynamic tracepoint or by looking at /proc/pid/fd, from Arnaldo Carvalho de Melo. . Add 'trace' beautifiers for lots of syscall arguments, from Arnaldo Carvalho de Melo. . Implement more compact 'trace' output by suppressing zeroed args, from Arnaldo Carvalho de Melo. . Show thread COMM by default in 'trace', from Arnaldo Carvalho de Melo. . Add option to show full timestamp in 'trace', from David Ahern. . Add 'record' command in 'trace', to record raw_syscalls:*, from David Ahern. . Add summary option to dump syscall statistics in 'trace', from David Ahern. . Improve error messages in 'trace', providing hints about system configuration steps needed for using it, from Ramkumar Ramachandra. . 'perf trace' now emits hints as to why tracing is not possible, helping the user to setup the system to allow tracing in the desired permission granularity, telling if the problem is due to debugfs not being mounted or with not enough permission for !root, /proc/sys/kernel/perf_event_paranoit value, etc. From Arnaldo Carvalho de Melo. * 'perf record' enhancements: . Check maximum frequency rate for record/top, emitting better error messages, from Jiri Olsa. . 'perf record' code cleanups, from David Ahern. . Improve write_output error message in 'perf record', from Adrian Hunter. . Allow specifying B/K/M/G unit to the --mmap-pages arguments, from Jiri Olsa. . Fix command line callchain attribute tests to handle the new -g/--call-chain semantics, from Arnaldo Carvalho de Melo. * 'perf kvm' enhancements: . Disable live kvm command if timerfd is not supported, from David Ahern. . Fix detection of non-core features, from David Ahern. * 'perf list' enhancements: . Add usage to 'perf list', from David Ahern. . Show error in 'perf list' if tracepoints not available, from Pekka Enberg. * 'perf probe' enhancements: . Support "$vars" meta argument syntax for local variables, allowing asking for all possible variables at a given probe point to be collected when it hits, from Masami Hiramatsu. * 'perf sched' enhancements: . Address the root cause of that 'perf sched' stack initialization build slowdown, by programmatically setting a big array after moving the global variable back to the stack. Fix from Adrian Hunter. * 'perf script' enhancements: . Set up output options for in-stream attributes, from Adrian Hunter. . Print addr by default for BTS in 'perf script', from Adrian Juntmer * 'perf stat' enhancements: . Improved messages when doing profiling in all or a subset of CPUs using a workload as the session delimitator, as in: 'perf stat --cpu 0,2 sleep 10s' from Arnaldo Carvalho de Melo. . Add units to nanosec-based counters in 'perf stat', from David Ahern. . Remove bogus info when using 'perf stat' -e cycles/instructions, from Ramkumar Ramachandra. * 'perf lock' enhancements: . 'perf lock' fixes and cleanups, from Davidlohr Bueso. * 'perf test' enhancements: . Fixup PERF_SAMPLE_TRANSACTION handling in sample synthesizing and 'perf test', from Adrian Hunter. . Clarify the "sample parsing" test entry, from Arnaldo Carvalho de Melo. . Consider PERF_SAMPLE_TRANSACTION in the "sample parsing" test, from Arnaldo Carvalho de Melo. . Memory leak fixes in 'perf test', from Felipe Pena. * 'perf bench' enhancements: . Change the procps visible command-name of invididual benchmark tests plus cleanups, from Ingo Molnar. * Generic perf tooling infrastructure/plumbing changes: . Separating data file properties from session, code reorganization from Jiri Olsa. . Fix version when building out of tree, as when using one of these: $ make help | grep perf perf-tar-src-pkg - Build perf-3.12.0.tar source tarball perf-targz-src-pkg - Build perf-3.12.0.tar.gz source tarball perf-tarbz2-src-pkg - Build perf-3.12.0.tar.bz2 source tarball perf-tarxz-src-pkg - Build perf-3.12.0.tar.xz source tarball $ from David Ahern. . Enhance option parse error message, showing just the help lines of the options affected, from Namhyung Kim. . libtraceevent updates from upstream trace-cmd repo, from Steven Rostedt. . Always use perf_evsel__set_sample_bit to set sample_type, from Adrian Hunter. . Memory and mmap leak fixes from Chenggang Qin. . Assorted build fixes for from David Ahern and Jiri Olsa. . Speed up and prettify the build system, from Ingo Molnar. . Implement addr2line directly using libbfd, from Roberto Vitillo. . Separate the GTK support in a separate libperf-gtk.so DSO, that is only loaded when --gtk is specified, from Namhyung Kim. . perf bash completion fixes and improvements from Ramkumar Ramachandra. . Support for Openembedded/Yocto -dbg packages, from Ricardo Ribalda Delgado. And lots and lots of other fixes and code reorganizations that did not make it into the list, see the shortlog, diffstat and the Git log for details!" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (300 commits) uprobes: Fix the memory out of bound overwrite in copy_insn() uprobes: Fix the wrong usage of current->utask in uprobe_copy_process() perf tools: Remove unneeded include perf record: Remove post_processing_offset variable perf record: Remove advance_output function perf record: Refactor feature handling into a separate function perf trace: Don't relookup fields by name in each sample perf tools: Fix version when building out of tree perf evsel: Ditch evsel->handler.data field uprobes: Export write_opcode() as uprobe_write_opcode() uprobes: Introduce arch_uprobe->ixol uprobes: Kill module_init() and module_exit() uprobes: Move function declarations out of arch perf/x86/intel: Add Ivy Bridge-EP uncore IRP box support perf/x86/intel/uncore: Add filter support for IvyBridge-EP QPI boxes perf: Factor out strncpy() in perf_event_mmap_event() tools/perf: Add required memory barriers perf: Fix arch_perf_out_copy_user default perf: Update a stale comment perf: Optimize perf_output_begin() -- address calculation ...
2013-11-09uprobes: Fix the memory out of bound overwrite in copy_insn()Oleg Nesterov
1. copy_insn() doesn't look very nice, all calculations are confusing and it is not immediately clear why do we read the 2nd page first. 2. The usage of inode->i_size is wrong on 32-bit machines. 3. "Instruction at end of binary" logic is simply wrong, it doesn't handle the case when uprobe->offset > inode->i_size. In this case "bytes" overflows, and __copy_insn() writes to the memory outside of uprobe->arch.insn. Yes, uprobe_register() checks i_size_read(), but this file can be truncated after that. All i_size checks are racy, we do this only to catch the obvious mistakes. Change copy_insn() to call __copy_insn() in a loop, simplify and fix the bytes/nbytes calculations. Note: we do not care if we read extra bytes after inode->i_size if we got the valid page. This is fine because the task gets the same page after page-fault, and arch_uprobe_analyze_insn() can't know how many bytes were actually read anyway. Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2013-11-09uprobes: Fix the wrong usage of current->utask in uprobe_copy_process()Oleg Nesterov
Commit aa59c53fd459 "uprobes: Change uprobe_copy_process() to dup xol_area" has a stupid typo, we need to setup t->utask->vaddr but the code wrongly uses current->utask. Even with this bug dup_xol_work() works "in practice", but only because get_unmapped_area(NULL, TASK_SIZE - PAGE_SIZE) likely returns the same address every time. Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2013-11-07Merge tag 'driver-core-3.13-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core / sysfs patches from Greg KH: "Here's the big driver core / sysfs update for 3.13-rc1. There's lots of dev_groups updates for different subsystems, as they all get slowly migrated over to the safe versions of the attribute groups (removing userspace races with the creation of the sysfs files.) Also in here are some kobject updates, devres expansions, and the first round of Tejun's sysfs reworking to enable it to be used by other subsystems as a backend for an in-kernel filesystem. All of these have been in linux-next for a while with no reported issues" * tag 'driver-core-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (83 commits) sysfs: rename sysfs_assoc_lock and explain what it's about sysfs: use generic_file_llseek() for sysfs_file_operations sysfs: return correct error code on unimplemented mmap() mdio_bus: convert bus code to use dev_groups device: Make dev_WARN/dev_WARN_ONCE print device as well as driver name sysfs: separate out dup filename warning into a separate function sysfs: move sysfs_hash_and_remove() to fs/sysfs/dir.c sysfs: remove unused sysfs_get_dentry() prototype sysfs: honor bin_attr.attr.ignore_lockdep sysfs: merge sysfs_elem_bin_attr into sysfs_elem_attr devres: restore zeroing behavior of devres_alloc() sysfs: fix sysfs_write_file for bin file input: gameport: convert bus code to use dev_groups input: serio: remove bus usage of dev_attrs input: serio: use DEVICE_ATTR_RO() i2o: convert bus code to use dev_groups memstick: convert bus code to use dev_groups tifm: convert bus code to use dev_groups virtio: convert bus code to use dev_groups ipack: convert bus code to use dev_groups ...
2013-11-06uprobes: Export write_opcode() as uprobe_write_opcode()Oleg Nesterov
set_swbp() and set_orig_insn() are __weak, but this is pointless because write_opcode() is static. Export write_opcode() as uprobe_write_opcode() for the upcoming arm port, this way it can actually override set_swbp() and use __opcode_to_mem_arm(bpinsn) instead if UPROBE_SWBP_INSN. Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2013-11-06uprobes: Introduce arch_uprobe->ixolOleg Nesterov
Currently xol_get_insn_slot() assumes that we should simply copy arch_uprobe->insn[] which is (ignoring arch_uprobe_analyze_insn) just the copy of the original insn. This is not true for arm which needs to create another insn to execute it out-of-line. So this patch simply adds the new member, ->ixol into the union. This doesn't make any difference for x86 and powerpc, but arm can divorce insn/ixol and initialize the correct xol insn in arch_uprobe_analyze_insn(). Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2013-11-06uprobes: Kill module_init() and module_exit()Oleg Nesterov
Turn module_init() into __initcall() and kill module_exit(). This code can't be compiled as a module so these module_*() calls only add the confusion, especially if arch-dependant code needs its own initialization hooks. Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2013-11-06perf: Factor out strncpy() in perf_event_mmap_event()Oleg Nesterov
While this is really minor, but strncpy() does the unnecessary zero-padding till the end of tmp[16] and it is called every time we are going to use the string literal. Turn these strncpy()'s into the single strlcpy() under the new label, saves 72 bytes. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131017182417.GA17753@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-06perf: Fix arch_perf_out_copy_user defaultPeter Zijlstra
The arch_perf_output_copy_user() default of __copy_from_user_inatomic() returns bytes not copied, while all other argument functions given DEFINE_OUTPUT_COPY() return bytes copied. Since copy_from_user_nmi() is the odd duck out by returning bytes copied where all other *copy_{to,from}* functions return bytes not copied, change it over and ammend DEFINE_OUTPUT_COPY() to expect bytes not copied. Oddly enough DEFINE_OUTPUT_COPY() already returned bytes not copied while expecting its worker functions to return bytes copied. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Acked-by: will.deacon@arm.com Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/r/20131030201622.GR16117@laptop.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-06perf: Update a stale commentPeter Zijlstra
Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Michael Neuling <mikey@neuling.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: james.hogan@imgtec.com Cc: Vince Weaver <vince@deater.net> Cc: Victor Kaplansky <VICTORK@il.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Anton Blanchard <anton@samba.org> Link: http://lkml.kernel.org/n/tip-9s5mze78gmlz19agt39i8rii@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-06perf: Optimize perf_output_begin() -- address calculationPeter Zijlstra
Rewrite the handle address calculation code to be clearer. Saves 8 bytes on x86_64-defconfig. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Michael Neuling <mikey@neuling.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: james.hogan@imgtec.com Cc: Vince Weaver <vince@deater.net> Cc: Victor Kaplansky <VICTORK@il.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Anton Blanchard <anton@samba.org> Link: http://lkml.kernel.org/n/tip-3trb2n2henb9m27tncef3ag7@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-06perf: Optimize perf_output_begin() -- lost_event casePeter Zijlstra
Avoid touching the lost_event and sample_data cachelines twince. Its not like we end up doing less work, but it might help to keep all accesses to these cachelines in one place. Due to code shuffle, this looses 4 bytes on x86_64-defconfig. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Michael Neuling <mikey@neuling.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: james.hogan@imgtec.com Cc: Vince Weaver <vince@deater.net> Cc: Victor Kaplansky <VICTORK@il.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Anton Blanchard <anton@samba.org> Link: http://lkml.kernel.org/n/tip-zfxnc58qxj0eawdoj31hhupv@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-06perf: Optimize perf_output_begin()Peter Zijlstra
There's no point in re-doing the memory-barrier when we fail the cmpxchg(). Also placing it after the space reservation loop makes it clearer it only separates the userpage->tail read from the data stores. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Michael Neuling <mikey@neuling.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: james.hogan@imgtec.com Cc: Vince Weaver <vince@deater.net> Cc: Victor Kaplansky <VICTORK@il.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Anton Blanchard <anton@samba.org> Link: http://lkml.kernel.org/n/tip-c19u6egfldyx86tpyc3zgkw9@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-06perf: Add unlikely() to the ring-buffer codePeter Zijlstra
Add unlikely() annotations to 'slow' paths: When having a sampling event but no output buffer; you have bigger issues -- also the bail is still faster than actually doing the work. When having a sampling event but a control page only buffer, you have bigger issues -- again the bail is still faster than actually doing work. Optimize for the case where you're not loosing events -- again, not doing the work is still faster but make sure that when you have to actually do work its as fast as possible. The typical watermark is 1/2 the buffer size, so most events will not take this path. Shrinks perf_output_begin() by 16 bytes on x86_64-defconfig. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Michael Neuling <mikey@neuling.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: james.hogan@imgtec.com Cc: Vince Weaver <vince@deater.net> Cc: Victor Kaplansky <VICTORK@il.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Anton Blanchard <anton@samba.org> Link: http://lkml.kernel.org/n/tip-wlg3jew3qnutm8opd0hyeuwn@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-06perf: Simplify the ring-buffer codePeter Zijlstra
By using CIRC_SPACE() we can obviate the need for perf_output_space(). Shrinks the size of perf_output_begin() by 17 bytes on x86_64-defconfig. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Michael Neuling <mikey@neuling.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: james.hogan@imgtec.com Cc: Vince Weaver <vince@deater.net> Cc: Victor Kaplansky <VICTORK@il.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Anton Blanchard <anton@samba.org> Link: http://lkml.kernel.org/n/tip-vtb0xb0llebmsdlfn1v5vtfj@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-04Merge branch 'perf/urgent' into perf/core to fix conflictsIngo Molnar
Conflicts: tools/perf/bench/numa.c Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29uprobes: Teach uprobe_copy_process() to handle CLONE_VFORKOleg Nesterov
uprobe_copy_process() does nothing if the child shares ->mm with the forking process, but there is a special case: CLONE_VFORK. In this case it would be more correct to do dup_utask() but avoid dup_xol(). This is not that important, the child should not unwind its stack too much, this can corrupt the parent's stack, but at least we need this to allow to ret-probe __vfork() itself. Note: in theory, it would be better to check task_pt_regs(p)->sp instead of CLONE_VFORK, we need to dup_utask() if and only if the child can return from the function called by the parent. But this needs the arch-dependant helper, and I think that nobody actually does clone(same_stack, CLONE_VM). Reported-by: Martin Cermak <mcermak@redhat.com> Reported-by: David Smith <dsmith@redhat.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2013-10-29uprobes: Change uprobe_copy_process() to dup xol_areaOleg Nesterov
This finally fixes the serious bug in uretprobes: a forked child crashes if the parent called fork() with the pending ret probe. Trivial test-case: # perf probe -x /lib/libc.so.6 __fork%return # perf record -e probe_libc:__fork perl -le 'fork || print "OK"' (the child doesn't print "OK", it is killed by SIGSEGV) If the child returns from the probed function it actually returns to trampoline_vaddr, because it got the copy of parent's stack mangled by prepare_uretprobe() when the parent entered this func. It crashes because a) this address is not mapped and b) until the previous change it doesn't have the proper->return_instances info. This means that uprobe_copy_process() has to create xol_area which has the trampoline slot, and its vaddr should be equal to parent's xol_area->vaddr. Unfortunately, uprobe_copy_process() can not simply do __create_xol_area(child, xol_area->vaddr). This could actually work but perf_event_mmap() doesn't expect the usage of foreign ->mm. So we offload this to task_work_run(), and pass the argument via not yet used utask->vaddr. We know that this vaddr is fine for install_special_mapping(), the necessary hole was recently "created" by dup_mmap() which skips the parent's VM_DONTCOPY area, and nobody else could use the new mm. Unfortunately, this also means that we can not handle the errors properly, we obviously can not abort the already completed fork(). So we simply print the warning if GFP_KERNEL allocation (the only possible reason) fails. Reported-by: Martin Cermak <mcermak@redhat.com> Reported-by: David Smith <dsmith@redhat.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
2013-10-29uprobes: Change uprobe_copy_process() to dup return_instancesOleg Nesterov
uprobe_copy_process() assumes that the new child doesn't need ->utask, it should be allocated by demand. But this is not true if the forking task has the pending ret- probes, the child should report them as well and thus it needs the copy of parent's ->return_instances chain. Otherwise the child crashes when it returns from the probed function. Alternatively we could cleanup the child's stack, but this needs per-arch changes and this is not what we want. At least systemtap expects a .return in the child too. Note: this change alone doesn't fix the problem, see the next change. Reported-by: Martin Cermak <mcermak@redhat.com> Reported-by: David Smith <dsmith@redhat.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
2013-10-29uprobes: Teach __create_xol_area() to accept the predefined vaddrOleg Nesterov
Currently xol_add_vma() uses get_unmapped_area() for area->vaddr, but the next patches need to use the fixed address. So this patch adds the new "vaddr" argument to __create_xol_area() which should be used as area->vaddr if it is nonzero. xol_add_vma() doesn't bother to verify that the predefined addr is not used, insert_vm_struct() should fail if find_vma_links() detects the overlap with the existing vma. Also, __create_xol_area() doesn't need __GFP_ZERO to allocate area. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
2013-10-29uprobes: Introduce __create_xol_area()Oleg Nesterov
No functional changes, preparation. Extract the code which actually allocates/installs the new area into the new helper, __create_xol_area(). While at it remove the unnecessary "ret = ENOMEM" and "ret = 0" in xol_add_vma(), they both have no effect. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
2013-10-29uprobes: Change the callsite of uprobe_copy_process()Oleg Nesterov
Preparation for the next patches. Move the callsite of uprobe_copy_process() in copy_process() down to the succesfull return. We do not care if copy_process() fails, uprobe_free_utask() won't be called in this case so the wrong ->utask != NULL doesn't matter. OTOH, with this change we know that copy_process() can't fail when uprobe_copy_process() is called, the new task should either return to user-mode or call do_exit(). This way uprobe_copy_process() can: 1. setup p->utask != NULL if necessary 2. setup uprobes_state.xol_area 3. use task_work_add(p) Also, move the definition of uprobe_copy_process() down so that it can see get_utask(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
2013-10-29perf: Fix the perf context switch optimizationPeter Zijlstra
Currently we only optimize the context switch between two contexts that have the same parent; this forgoes the optimization between parent and child context, even though these contexts could be equivalent too. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Shishkin, Alexander <alexander.shishkin@intel.com> Link: http://lkml.kernel.org/r/20131007164257.GH3081@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29perf: Change zero-padding of strings in perf_event_mmap_event()Peter Zijlstra
Oleg complained about the excessive 0-ing in perf_event_mmap_event(), so try and be smarter about it while keeping it fairly fool proof and avoid leaking random bits out to userspace. Suggested-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-8jirlm99m6if2z13wd6rbyu6@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29perf: Do not waste PAGE_SIZE bytes for ALIGN(8) in perf_event_mmap_event()Oleg Nesterov
perf_event_mmap_event() does kzalloc(PATH_MAX + sizeof(u64)) to ensure we can align the size later. However this means that we actually allocate PAGE_SIZE * 2 buffer, seems too much. Change this code to allocate PATH_MAX==PAGE_SIZE bytes, but tell d_path() to not use the last sizeof(u64) bytes. Note: it is not clear why do we need __GFP_ZERO, see the next patch. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131016201004.GC23214@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29perf: Kill the dead !vma->vm_mm code in perf_event_mmap_event()Oleg Nesterov
1. perf_event_mmap(vma) is never called with a gate_vma-like arg, remove the "if (!vma->vm_mm)" code. 2. arch_vma_name() can use the chached value of mmap_event->vma. 3. Change the code to not call arch_vma_name() twice. 4. Purely cosmetic, but since we use "goto got_name" all the time remove "else" from "[stack]" branch just for symmetry. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131016200945.GB23214@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29perf: Remove useless atomic_tPeter Zijlstra
There's nothing atomic about atomic_set vs atomic_read; so remove the atomic_t usage. Also, make running_sample_length static as it really is (and should be) local to this translation unit. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: eranian@google.com Cc: Don Zickus <dzickus@redhat.com> Cc: jmario@redhat.com Cc: acme@infradead.org Cc: dave.hansen@linux.intel.com Link: http://lkml.kernel.org/n/tip-vw9lg588x1ic248whybjon0c@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29perf: Fix perf ring buffer memory orderingPeter Zijlstra
The PPC64 people noticed a missing memory barrier and crufty old comments in the perf ring buffer code. So update all the comments and add the missing barrier. When the architecture implements local_t using atomic_long_t there will be double barriers issued; but short of introducing more conditional barrier primitives this is the best we can do. Reported-by: Victor Kaplansky <victork@il.ibm.com> Tested-by: Victor Kaplansky <victork@il.ibm.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: michael@ellerman.id.au Cc: Paul McKenney <paulmck@linux.vnet.ibm.com> Cc: Michael Neuling <mikey@neuling.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: anton@samba.org Cc: benh@kernel.crashing.org Link: http://lkml.kernel.org/r/20131025173749.GG19466@laptop.lan Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29Merge branch 'perf/urgent' into perf/coreIngo Molnar
Conflicts: tools/perf/builtin-record.c tools/perf/builtin-top.c tools/perf/util/hist.h
2013-10-19Merge 3.12-rc6 into driver-core-nextGreg Kroah-Hartman
We want these fixes here too. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-17perf: Disable PERF_RECORD_MMAP2 supportStephane Eranian
For now, we disable the extended MMAP record support (MMAP2). We have identified cases where it would not report the correct mapping information, clone(VM_CLONE) but with separate pids. We will revisit the support once we find a solution for this case. The patch changes the kernel to return EINVAL if attr->mmap2 is set. The patch also modifies the perf tool to use regular PERF_RECORD_MMAP for synthetic events and it also prevents the tool from requesting attr->mmap2 mode because the kernel would reject it. The support will be revisited once the kenrel interface is updated. In V2, we reduce the patch to the strict minimum. In V3, we avoid calling perf_event_open() with mmap2 set because we know it will fail and require fallback retry. Signed-off-by: Stephane Eranian <eranian@google.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131017173215.GA8820@quad Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-10-04perf: Add generic transaction flagsAndi Kleen
Add a generic qualifier for transaction events, as a new sample type that returns a flag word. This is particularly useful for qualifying aborts: to distinguish aborts which happen due to asynchronous events (like conflicts caused by another CPU) versus instructions that lead to an abort. The tuning strategies are very different for those cases, so it's important to distinguish them easily and early. Since it's inconvenient and inflexible to filter for this in the kernel we report all the events out and allow some post processing in user space. The flags are based on the Intel TSX events, but should be fairly generic and mostly applicable to other HTM architectures too. In addition to various flag words there's also reserved space to report an program supplied abort code. For TSX this is used to distinguish specific classes of aborts, like a lock busy abort when doing lock elision. Flags: Elision and generic transactions (ELISION vs TRANSACTION) (HLE vs RTM on TSX; IBM etc. would likely only use TRANSACTION) Aborts caused by current thread vs aborts caused by others (SYNC vs ASYNC) Retryable transaction (RETRY) Conflicts with other threads (CONFLICT) Transaction write capacity overflow (CAPACITY WRITE) Transaction read capacity overflow (CAPACITY READ) Transactions implicitely aborted can also return an abort code. This can be used to signal specific events to the profiler. A common case is abort on lock busy in a RTM eliding library (code 0xff) To handle this case we include the TSX abort code Common example aborts in TSX would be: - Data conflict with another thread on memory read. Flags: TRANSACTION|ASYNC|CONFLICT - executing a WRMSR in a transaction. Flags: TRANSACTION|SYNC - HLE transaction in user space is too large Flags: ELISION|SYNC|CAPACITY-WRITE The only flag that is somewhat TSX specific is ELISION. This adds the perf core glue needed for reporting the new flag word out. v2: Add MEM/MISC v3: Move transaction to the end v4: Separate capacity-read/write and remove misc v5: Remove _SAMPLE. Move abort flags to 32bit. Rename transaction to txn Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1379688044-14173-2-git-send-email-andi@firstfloor.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-04perf: Enforce 1 as lower limit for perf_event_max_sample_rateKnut Petersen
/proc/sys/kernel/perf_event_max_sample_rate will accept negative values as well as 0. Negative values are unreasonable, and 0 causes a divide by zero exception in perf_proc_update_handler. This patch enforces a lower limit of 1. Signed-off-by: Knut Petersen <Knut_Petersen@t-online.de> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/5242DB0C.4070005@t-online.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-04perf: Fix perf_pmu_migrate_contextPeter Zijlstra
While auditing the list_entry usage due to a trinity bug I found that perf_pmu_migrate_context violates the rules for perf_event::event_entry. The problem is that perf_event::event_entry is a RCU list element, and hence we must wait for a full RCU grace period before re-using the element after deletion. Therefore the usage in perf_pmu_migrate_context() which re-uses the entry immediately is broken. For now introduce another list_head into perf_event for this specific usage. This doesn't actually fix the trinity report because that never goes through this code. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-mkj72lxagw1z8fvjm648iznw@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-29Merge 3.12-rc3 into driver-core-nextGreg Kroah-Hartman
We want the driver core and sysfs fixes in here to make merges and development easier. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-09-26pmu_bus: convert bus code to use dev_groupsGreg Kroah-Hartman
The dev_attrs field of struct bus_type is going away soon, dev_groups should be used instead. This converts the pmu bus code to use the correct field. Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-09-20perf: Fix capabilities bitfield compatibility in 'struct perf_event_mmap_page'Peter Zijlstra
Solve the problems around the broken definition of perf_event_mmap_page:: cap_usr_time and cap_usr_rdpmc fields which used to overlap, partially fixed by: 860f085b74e9 ("perf: Fix broken union in 'struct perf_event_mmap_page'") The problem with the fix (merged in v3.12-rc1 and not yet released officially), noticed by Vince Weaver is that the new behavior is not detectable by new user-space, and that due to the reuse of the field names it's easy to mis-compile a binary if old headers are used on a new kernel or new headers are used on an old kernel. To solve all that make this change explicit, detectable and self-contained, by iterating the ABI the following way: - Always clear bit 0, and rename it to usrpage->cap_bit0, to at least not confuse old user-space binaries. RDPMC will be marked as unavailable to old binaries but that's within the ABI, this is a capability bit. - Rename bit 1 to ->cap_bit0_is_deprecated and always set it to 1, so new libraries can reliably detect that bit 0 is deprecated and perma-zero without having to check the kernel version. - Use bits 2, 3, 4 for the newly defined, correct functionality: cap_user_rdpmc : 1, /* The RDPMC instruction can be used to read counts */ cap_user_time : 1, /* The time_* fields are used */ cap_user_time_zero : 1, /* The time_zero field is used */ - Rename all the bitfield names in perf_event.h to be different from the old names, to make sure it's not possible to mis-compile it accidentally with old assumptions. The 'size' field can then be used in the future to add new fields and it will act as a natural ABI version indicator as well. Also adjust tools/perf/ userspace for the new definitions, noticed by Adrian Hunter. Reported-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Also-Fixed-by: Adrian Hunter <adrian.hunter@intel.com> Link: http://lkml.kernel.org/n/tip-zr03yxjrpXesOzzupszqglbv@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-12uprobes: Fix utask->depth accounting in handle_trampoline()Oleg Nesterov
Currently utask->depth is simply the number of allocated/pending return_instance's in uprobe_task->return_instances list. handle_trampoline() should decrement this counter every time we handle/free an instance, but due to typo it does this only if ->chained == T. This means that in the likely case this counter is never decremented and the probed task can't report more than MAX_URETPROBE_DEPTH events. Reported-by: Mikhail Kulemin <Mikhail.Kulemin@ru.ibm.com> Reported-by: Hemant Kumar Shaw <hkshaw@linux.vnet.ibm.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Anton Arapov <anton@redhat.com> Cc: masami.hiramatsu.pt@hitachi.com Cc: srikar@linux.vnet.ibm.com Cc: systemtap@sourceware.org Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20130911154726.GA8093@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-11perf: Fix up MMAP2 buffer space reservationArnaldo Carvalho de Melo
The ino_generation field was added in the PERF_RECORD_MMAP2 record in the 13d7a24 cset but no space for it was allocated, corrupting the PERF_FORMAT_{TIME,CPU,TID,etc} area (sample_type/sample_id_all), fix it. Detected with one of the regression tests done by 'perf test': [root@sandy ~]# perf test -v 7 7: Validate PERF_RECORD_* events & perf_sample fields : --- start --- 61315294449606 0 PERF_RECORD_SAMPLE 61315294453161 0 PERF_RECORD_SAMPLE 61315294454441 0 PERF_RECORD_SAMPLE 61315294455709 0 PERF_RECORD_SAMPLE 61315295600899 0 PERF_RECORD_COMM: sleep:6500 27917287430500 342521613 PERF_RECORD_MMAP2 6500/6500: [0x400000(0x7000) @ 0 00:1d 311442 9016]: /usr/bin/sleep MMAP2 going backwards in time, prev=61315295600899, curr=27917287430500 MMAP2 with unexpected cpu, expected 0, got 342521613 MMAP2 with unexpected pid, expected 6500, got 1701606191 MMAP2 with unexpected tid, expected 6500, got 28773 27917287430500 342561333 PERF_RECORD_MMAP2 6500/6500: [0x3b7e000000(0x223000) @ 0 00:1d 309186 9016]: /usr/lib64/ld-2.16.so MMAP2 with unexpected cpu, expected 0, got 342561333 MMAP2 with unexpected pid, expected 6500, got 1932408369 MMAP2 with unexpected tid, expected 6500, got 111 27917287430500 342600095 PERF_RECORD_MMAP2 6500/6500: [0x7fffbd7dc000(0x1000) @ 0x7fffbd7dc000 00:00 0 0]: [vdso] MMAP2 with unexpected cpu, expected 0, got 342600095 MMAP2 with unexpected pid, expected 6500, got 1935963739 MMAP2 with unexpected tid, expected 6500, got 23919 27917287430500 342882834 PERF_RECORD_MMAP2 6500/6500: [0x3b7e400000(0x3b8000) @ 0 00:1d 309187 9016]: /usr/lib64/libc-2.16.so MMAP2 with unexpected cpu, expected 0, got 342882834 MMAP2 with unexpected pid, expected 6500, got 909192754 MMAP2 with unexpected tid, expected 6500, got 7303982 61316297195411 0 PERF_RECORD_EXIT(6500:6500):(6500:6500) ---- end ---- Validate PERF_RECORD_* events & perf_sample fields: FAILED! [root@sandy ~]# After this patch: [root@sandy ~]# perf test 7 7: Validate PERF_RECORD_* events & perf_sample fields : Ok [root@sandy ~]# Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Stephane Eranian <eranian@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-heeuv986b8ha7whqg4o3he7c@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-09-04Merge branches 'perf-urgent-for-linus' and 'perf-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf changes from Ingo Molnar: "As a first remark I'd like to point out that the obsolete '-f' (--force) option, which has not done anything for several releases, has been removed from 'perf record' and related utilities. Everyone please update muscle memory accordingly! :-) Main changes on the perf kernel side: - Performance optimizations: . for trace events, by Steve Rostedt. . for time values, by Peter Zijlstra - New hardware support: . for Intel Silvermont (22nm Atom) CPUs, by Zheng Yan . for Intel SNB-EP uncore PMUs, by Zheng Yan - Enhanced hardware support: . for Intel uncore PMUs: add filter support for QPI boxes, by Zheng Yan - Core perf events code enhancements and fixes: . for full-nohz feature handling, by Frederic Weisbecker . for group events, by Jiri Olsa . for call chains, by Frederic Weisbecker . for event stream parsing, by Adrian Hunter - New ABI details: . Add attr->mmap2 attribute, by Stephane Eranian . Add PERF_EVENT_IOC_ID ioctl to return event ID, by Jiri Olsa . Export u64 time_zero on the mmap header page to allow TSC calculation, by Adrian Hunter . Add dummy software event, by Adrian Hunter. . Add a new PERF_SAMPLE_IDENTIFIER to make samples always parseable, by Adrian Hunter. . Make Power7 events available via sysfs, by Runzhen Wang. - Code cleanups and refactorings: . for nohz-full, by Frederic Weisbecker . for group events, by Jiri Olsa - Documentation updates: . for perf_event_type, by Peter Zijlstra Main changes on the perf tooling side (some of these tooling changes utilize the above kernel side changes): - Lots of 'perf trace' enhancements: . Make 'perf trace' command line arguments consistent with 'perf record', by David Ahern. . Allow specifying syscalls a la strace, by Arnaldo Carvalho de Melo. . Add --verbose and -o/--output options, by Arnaldo Carvalho de Melo. . Support ! in -e expressions, to filter a list of syscalls, by Arnaldo Carvalho de Melo. . Arg formatting improvements to allow masking arguments in syscalls such as futex and open, where the some arguments are ignored and thus should not be printed depending on other args, by Arnaldo Carvalho de Melo. . Beautify futex open, openat, open_by_handle_at, lseek and futex syscalls, by Arnaldo Carvalho de Melo. . Add option to analyze events in a file versus live, so that one can do: [root@zoo ~]# perf record -a -e raw_syscalls:* sleep 1 [ perf record: Woken up 0 times to write data ] [ perf record: Captured and wrote 25.150 MB perf.data (~1098836 samples) ] [root@zoo ~]# perf trace -i perf.data -e futex --duration 1 17.799 ( 1.020 ms): 7127 futex(uaddr: 0x7fff3f6c6674, op: 393, val: 1, utime: 0x7fff3f6c6470, ua 113.344 (95.429 ms): 7127 futex(uaddr: 0x7fff3f6c6674, op: 393, val: 1, utime: 0x7fff3f6c6470, uaddr2: 0x7fff3f6c6648, val3: 4294967 133.778 ( 1.042 ms): 18004 futex(uaddr: 0x7fff3f6c6674, op: 393, val: 1, utime: 0x7fff3f6c6470, uaddr2: 0x7fff3f6c6648, val3: 429496 [root@zoo ~]# By David Ahern. . Honor target pid / tid options when analyzing a file, by David Ahern. . Introduce better formatting of syscall arguments, including so far beautifiers for mmap, madvise, syscall return values, by Arnaldo Carvalho de Melo. . Handle HUGEPAGE defines in the mmap beautifier, by David Ahern. - 'perf report/top' enhancements: . Do annotation using /proc/kcore and /proc/kallsyms when available, removing the forced need for a vmlinux file kernel assembly annotation. This also improves this use case because vmlinux has just the initial kernel image, not what is actually in use after various code patchings by things like alternatives. By Adrian Hunter. . Add --ignore-callees=<regex> option to collapse undesired parts of call graphs, by Greg Price. . Simplify symbol filtering by doing it at machine class level, by Adrian Hunter. . Add support for callchains in the gtk UI, by Namhyung Kim. . Add --objdump option to 'perf top', by Sukadev Bhattiprolu. - 'perf kvm' enhancements: . Add option to print only events that exceed a specified time duration, by David Ahern. . Improve stack trace printing, by David Ahern. . Update documentation of the live command, by David Ahern . Add perf kvm stat live mode that combines aspects of 'perf kvm stat' record and report, by David Ahern. . Add option to analyze specific VM in perf kvm stat report, by David Ahern. . Do not require /lib/modules/* on a guest, by Jason Wessel. - 'perf script' enhancements: . Fix symbol offset computation for some dsos, by David Ahern. . Fix named threads support, by David Ahern. . Don't install scripting files files when perl/python support is disabled, by Arnaldo Carvalho de Melo. - 'perf test' enhancements: . Add various improvements and fixes to the "vmlinux matches kallsyms" 'perf test' entry, related to the /proc/kcore annotation feature. By Adrian Hunter. . Add sample parsing test, by Adrian Hunter. . Add test for reading object code, by Adrian Hunter. . Add attr record group sampling test, by Jiri Olsa. . Misc testing infrastructure improvements and other details, by Jiri Olsa. - 'perf list' enhancements: . Skip unsupported hardware events, by Namhyung Kim. . List pmu events, by Andi Kleen. - 'perf diff' enhancements: . Add support for more than two files comparison, by Jiri Olsa. - 'perf sched' enhancements: . Various improvements, including removing reliance on some scheduler tracepoints that provide the same information as the PERF_RECORD_{FORK,EXIT} events. By David Ahern. . Remove odd build stall by moving a large struct initialization from a local variable to a global one, by Namhyung Kim. - 'perf stat' enhancements: . Add --initial-delay option to skip measuring for a defined startup phase, by Andi Kleen. - Generic perf tooling infrastructure/plumbing changes: . Tidy up sample parsing validation, by Adrian Hunter. . Fix up jobserver setup in libtraceevent Makefile. by Arnaldo Carvalho de Melo. . Debug improvements, by Adrian Hunter. . Fix correlation of samples coming after PERF_RECORD_EXIT event, by David Ahern. . Improve robustness of the topology parsing code, by Stephane Eranian. . Add group leader sampling, that allows just one event in a group to sample while the other events have just its values read, by Jiri Olsa. . Add support for a new modifier "D", which requests that the event, or group of events, be pinned to the PMU. By Michael Ellerman. . Support callchain sorting based on addresses, by Andi Kleen . Prep work for multi perf data file storage, by Jiri Olsa. . libtraceevent cleanups, by Namhyung Kim. And lots and lots of other fixes and code reorganizations that did not make it into the list, see the shortlog, diffstat and the Git log for details!" [ Also merge a leftover from the 3.11 cycle ] * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf: Prevent race in unthrottling code * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (237 commits) perf trace: Tell arg formatters the arg index perf trace: Add beautifier for open's flags arg perf trace: Add beautifier for lseek's whence arg perf tools: Fix symbol offset computation for some dsos perf list: Skip unsupported events perf tests: Add 'keep tracking' test perf tools: Add support for PERF_COUNT_SW_DUMMY perf: Add a dummy software event to keep tracking perf trace: Add beautifier for futex 'operation' parm perf trace: Allow syscall arg formatters to mask args perf: Convert kmalloc_node(...GFP_ZERO...) to kzalloc_node() perf: Export struct perf_branch_entry to userspace perf: Add attr->mmap2 attribute to an event perf/x86: Add Silvermont (22nm Atom) support perf/x86: use INTEL_UEVENT_EXTRA_REG to define MSR_OFFCORE_RSP_X perf trace: Handle missing HUGEPAGE defines perf trace: Honor target pid / tid options when analyzing a file perf trace: Add option to analyze events in a file versus live perf evlist: Add tracepoint lookup by name perf tests: Add a sample parsing test ...
2013-09-03Merge branch 'for-3.12' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup updates from Tejun Heo: "A lot of activities on the cgroup front. Most changes aren't visible to userland at all at this point and are laying foundation for the planned unified hierarchy. - The biggest change is decoupling the lifetime management of css (cgroup_subsys_state) from that of cgroup's. Because controllers (cpu, memory, block and so on) will need to be dynamically enabled and disabled, css which is the association point between a cgroup and a controller may come and go dynamically across the lifetime of a cgroup. Till now, css's were created when the associated cgroup was created and stayed till the cgroup got destroyed. Assumptions around this tight coupling permeated through cgroup core and controllers. These assumptions are gradually removed, which consists bulk of patches, and css destruction path is completely decoupled from cgroup destruction path. Note that decoupling of creation path is relatively easy on top of these changes and the patchset is pending for the next window. - cgroup has its own event mechanism cgroup.event_control, which is only used by memcg. It is overly complex trying to achieve high flexibility whose benefits seem dubious at best. Going forward, new events will simply generate file modified event and the existing mechanism is being made specific to memcg. This pull request contains prepatory patches for such change. - Various fixes and cleanups" Fixed up conflict in kernel/cgroup.c as per Tejun. * 'for-3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (69 commits) cgroup: fix cgroup_css() invocation in css_from_id() cgroup: make cgroup_write_event_control() use css_from_dir() instead of __d_cgrp() cgroup: make cgroup_event hold onto cgroup_subsys_state instead of cgroup cgroup: implement CFTYPE_NO_PREFIX cgroup: make cgroup_css() take cgroup_subsys * instead and allow NULL subsys cgroup: rename cgroup_css_from_dir() to css_from_dir() and update its syntax cgroup: fix cgroup_write_event_control() cgroup: fix subsystem file accesses on the root cgroup cgroup: change cgroup_from_id() to css_from_id() cgroup: use css_get() in cgroup_create() to check CSS_ROOT cpuset: remove an unncessary forward declaration cgroup: RCU protect each cgroup_subsys_state release cgroup: move subsys file removal to kill_css() cgroup: factor out kill_css() cgroup: decouple cgroup_subsys_state destruction from cgroup destruction cgroup: replace cgroup->css_kill_cnt with ->nr_css cgroup: bounce cgroup_subsys_state ref kill confirmation to a work item cgroup: move cgroup->subsys[] assignment to online_css() cgroup: reorganize css init / exit paths cgroup: add __rcu modifier to cgroup->subsys[] ...
2013-09-02perf: Add attr->mmap2 attribute to an eventStephane Eranian
Adds a new PERF_RECORD_MMAP2 record type which is essence an expanded version of PERF_RECORD_MMAP. Used to request mmap records with more information about the mapping, including device major, minor and the inode number and generation for mappings associated with files or shared memory segments. Works for code and data (with attr->mmap_data set). Existing PERF_RECORD_MMAP record is unmodified by this patch. Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Link: http://lkml.kernel.org/r/1377079825-19057-2-git-send-email-eranian@google.com [ Added Al to the Cc:. Are the ino, maj/min exports of vma->vm_file OK? ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-02perf: Prevent race in unthrottling codeJiri Olsa
The current throttling code triggers WARN below via following workload (only hit on AMD machine with 48 CPUs): # while [ 1 ]; do perf record perf bench sched messaging; done WARNING: at arch/x86/kernel/cpu/perf_event.c:1054 x86_pmu_start+0xc6/0x100() SNIP Call Trace: <IRQ> [<ffffffff815f62d6>] dump_stack+0x19/0x1b [<ffffffff8105f531>] warn_slowpath_common+0x61/0x80 [<ffffffff8105f60a>] warn_slowpath_null+0x1a/0x20 [<ffffffff810213a6>] x86_pmu_start+0xc6/0x100 [<ffffffff81129dd2>] perf_adjust_freq_unthr_context.part.75+0x182/0x1a0 [<ffffffff8112a058>] perf_event_task_tick+0xc8/0xf0 [<ffffffff81093221>] scheduler_tick+0xd1/0x140 [<ffffffff81070176>] update_process_times+0x66/0x80 [<ffffffff810b9565>] tick_sched_handle.isra.15+0x25/0x60 [<ffffffff810b95e1>] tick_sched_timer+0x41/0x60 [<ffffffff81087c24>] __run_hrtimer+0x74/0x1d0 [<ffffffff810b95a0>] ? tick_sched_handle.isra.15+0x60/0x60 [<ffffffff81088407>] hrtimer_interrupt+0xf7/0x240 [<ffffffff81606829>] smp_apic_timer_interrupt+0x69/0x9c [<ffffffff8160569d>] apic_timer_interrupt+0x6d/0x80 <EOI> [<ffffffff81129f74>] ? __perf_event_task_sched_in+0x184/0x1a0 [<ffffffff814dd937>] ? kfree_skbmem+0x37/0x90 [<ffffffff815f2c47>] ? __slab_free+0x1ac/0x30f [<ffffffff8118143d>] ? kfree+0xfd/0x130 [<ffffffff81181622>] kmem_cache_free+0x1b2/0x1d0 [<ffffffff814dd937>] kfree_skbmem+0x37/0x90 [<ffffffff814e03c4>] consume_skb+0x34/0x80 [<ffffffff8158b057>] unix_stream_recvmsg+0x4e7/0x820 [<ffffffff814d5546>] sock_aio_read.part.7+0x116/0x130 [<ffffffff8112c10c>] ? __perf_sw_event+0x19c/0x1e0 [<ffffffff814d5581>] sock_aio_read+0x21/0x30 [<ffffffff8119a5d0>] do_sync_read+0x80/0xb0 [<ffffffff8119ac85>] vfs_read+0x145/0x170 [<ffffffff8119b699>] SyS_read+0x49/0xa0 [<ffffffff810df516>] ? __audit_syscall_exit+0x1f6/0x2a0 [<ffffffff81604a19>] system_call_fastpath+0x16/0x1b ---[ end trace 622b7e226c4a766a ]--- The reason is a race in perf_event_task_tick() throttling code. The race flow (simplified code): - perf_throttled_count is per cpu variable and is CPU throttling flag, here starting with 0 - perf_throttled_seq is sequence/domain for allowed count of interrupts within the tick, gets increased each tick on single CPU (CPU bounded event): ... workload perf_event_task_tick: | | T0 inc(perf_throttled_seq) | T1 needs_unthr = xchg(perf_throttled_count, 0) == 0 tick gets interrupted: ... event gets throttled under new seq ... T2 last NMI comes, event is throttled - inc(perf_throttled_count) back to tick: | perf_adjust_freq_unthr_context: | | T3 unthrottling is skiped for event (needs_unthr == 0) | T4 event is stop and started via freq adjustment | tick ends ... workload ... no sample is hit for event ... perf_event_task_tick: | | T5 needs_unthr = xchg(perf_throttled_count, 0) != 0 (from T2) | T6 unthrottling is done on event (interrupts == MAX_INTERRUPTS) | event is already started (from T4) -> WARN Fixing this by not checking needs_unthr again and thus check all events for unthrottling. Signed-off-by: Jiri Olsa <jolsa@redhat.com> Reported-by: Jan Stancek <jstancek@redhat.com> Suggested-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1377355554-8934-1-git-send-email-jolsa@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-08-29perf: make events stream always parsableAdrian Hunter
The event stream is not always parsable because the format of a sample is dependent on the sample_type of the selected event. When there is more than one selected event and the sample_types are not the same then parsing becomes problematic. A sample can be matched to its selected event using the ID that is allocated when the event is opened. Unfortunately, to get the ID from the sample means first parsing it. This patch adds a new sample format bit PERF_SAMPLE_IDENTIFER that puts the ID at a fixed position so that the ID can be retrieved without parsing the sample. For sample events, that is the first position immediately after the header. For non-sample events, that is the last position. In this respect parsing samples requires that the sample_type and ID values are recorded. For example, perf tools records struct perf_event_attr and the IDs within the perf.data file. Those must be read first before it is possible to parse samples found later in the perf.data file. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Tested-by: Stephane Eranian <eranian@google.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1377591794-30553-6-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-08-26cgroup: rename cgroup_css_from_dir() to css_from_dir() and update its syntaxTejun Heo
cgroup_css_from_dir() will grow another user. In preparation, make the following changes. * All css functions are prefixed with just "css_", rename it to css_from_dir(). * Take dentry * instead of file * as dentry is what ultimately identifies a cgroup and file may not always be available. Note that the function now checkes whether @dentry->d_inode is NULL as the caller now may specify a negative dentry. * Make it take cgroup_subsys * instead of integer subsys_id. This simplifies the function and allows specifying no subsystem for cgroup->dummy_css. * Make return section a bit less verbose. This patch doesn't introduce any behavior changes. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com>
2013-08-16perf: Do not compute time values unnecessarilyPeter Zijlstra
We should not be calling calc_timer_values() for events that do not actually have an mmap()'ed userpage. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20130802191630.GT27162@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-08-16perf: Account freq events globallyFrederic Weisbecker
Freq events may not always be affine to a particular CPU. As such, account_event_cpu() may crash if we account per cpu a freq event that has event->cpu == -1. To solve this, lets account freq events globally. In practice this doesn't change much the picture because perf tools create per-task perf events with one event per CPU by default. Profiling a single CPU is usually a corner case so there is no much point in optimizing things that way. Reported-by: Jiri Olsa <jolsa@redhat.com> Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Tested-by: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1375460996-16329-3-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>