user/sven/linux.git/include/linux/perf_event.h, branch v3.10.44

perf: Drop sample rate when sampling is too slow

2014-06-11T19:03:26Z

commit 14c63f17b1fde5a575a28e96547a22b451c71fb5 upstream. This patch keeps track of how long perf's NMI handler is taking, and also calculates how many samples perf can take a second. If the sample length times the expected max number of samples exceeds a configurable threshold, it drops the sample rate. This way, we don't have a runaway sampling process eating up the CPU. This patch can tend to drop the sample rate down to level where perf doesn't work very well. *BUT* the alternative is that my system hangs because it spends all of its time handling NMIs. I'll take a busted performance tool over an entire system that's busted and undebuggable any day. BTW, my suspicion is that there's still an underlying bug here. Using the HPET instead of the TSC is definitely a contributing factor, but I suspect there are some other things going on. But, I can't go dig down on a bug like that with my machine hanging all the time. Signed-off-by: Dave Hansen Acked-by: Peter Zijlstra Cc: paulus@samba.org Cc: acme@ghostprotocols.net Cc: Dave Hansen [ Prettified it a bit. ] Signed-off-by: Ingo Molnar Cc: Weng Meiling Signed-off-by: Greg Kroah-Hartman

perf: Fix perf mmap bugs

2013-05-28T09:05:08Z

Vince reported a problem found by his perf specific trinity fuzzer. Al noticed 2 problems with perf's mmap(): - it has issues against fork() since we use vma->vm_mm for accounting. - it has an rb refcount leak on double mmap(). We fix the issues against fork() by using VM_DONTCOPY; I don't think there's code out there that uses this; we didn't hear about weird accounting problems/crashes. If we do need this to work, the previously proposed VM_PINNED could make this work. Aside from the rb reference leak spotted by Al, Vince's example prog was indeed doing a double mmap() through the use of perf_event_set_output(). This exposes another problem, since we now have 2 events with one buffer, the accounting gets screwy because we account per event. Fix this by making the buffer responsible for its own accounting. Reported-by: Vince Weaver Signed-off-by: Peter Zijlstra Cc: Al Viro Cc: Paul Mackerras Cc: Arnaldo Carvalho de Melo Link: http://lkml.kernel.org/r/20130528085548.GA12193@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar

Merge commit '8700c95adb03' into timers/nohz

2013-05-02T15:54:19Z

The full dynticks tree needs the latest RCU and sched upstream updates in order to fix some dependencies. Merge a common upstream merge point that has these updates. Conflicts: include/linux/perf_event.h kernel/rcutree.h kernel/rcutree_plugin.h Signed-off-by: Frederic Weisbecker

perf: New helper to prevent full dynticks CPUs from stopping tick

2013-04-22T17:59:39Z

Provide a new helper that help full dynticks CPUs to prevent from stopping their tick in case there are events in the local rotation list. This way we make sure that perf_event_task_tick() is serviced on demand. Signed-off-by: Frederic Weisbecker Cc: Chris Metcalf Cc: Christoph Lameter Cc: Geoff Levand Cc: Gilad Ben Yossef Cc: Hakan Akkan Cc: Ingo Molnar Cc: Kevin Hilman Cc: Li Zhong Cc: Oleg Nesterov Cc: Paul E. McKenney Cc: Paul Gortmaker Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner Cc: Stephane Eranian Cc: Jiri Olsa

Merge branch 'for-tip' of git://git.kernel.org/pub/scm/linux/kernel/git/rric/oprofile into perf/core

2013-04-08T09:43:30Z

Pull IBM zEnterprise EC12 support patchlet from Robert Richter. Signed-off-by: Ingo Molnar

perf: Add generic memory sampling interface

2013-04-01T15:15:59Z

This patch adds PERF_SAMPLE_DATA_SRC. PERF_SAMPLE_DATA_SRC collects the data source, i.e., where did the data associated with the sampled instruction come from. Information is stored in a perf_mem_data_src structure. It contains opcode, mem level, tlb, snoop, lock information, subject to availability in hardware. Signed-off-by: Stephane Eranian Cc: peterz@infradead.org Cc: ak@linux.intel.com Cc: acme@redhat.com Cc: jolsa@redhat.com Cc: namhyung.kim@lge.com Link: http://lkml.kernel.org/r/1359040242-8269-8-git-send-email-eranian@google.com Signed-off-by: Ingo Molnar Signed-off-by: Arnaldo Carvalho de Melo

perf/core: Add weighted samples

2013-04-01T15:15:44Z

For some events it's useful to weight sample with a hardware provided number. This expresses how expensive the action the sample represent was. This allows the profiler to scale the samples to be more informative to the programmer. There is already the period which is used similarly, but it means something different, so I chose to not overload it. Instead a new sample type for WEIGHT is added. Can be used for multiple things. Initially it is used for TSX abort costs and profiling by memory latencies (so to make expensive load appear higher up in the histograms). The concept is quite generic and can be extended to many other kinds of events or architectures, as long as the hardware provides suitable auxillary values. In principle it could be also used for software tracepoints. This adds the generic glue. A new optional sample format for a 64-bit weight value. Signed-off-by: Andi Kleen Signed-off-by: Stephane Eranian Cc: peterz@infradead.org Cc: acme@redhat.com Cc: jolsa@redhat.com Cc: namhyung.kim@lge.com Link: http://lkml.kernel.org/r/1359040242-8269-5-git-send-email-eranian@google.com Signed-off-by: Ingo Molnar Signed-off-by: Arnaldo Carvalho de Melo

perf/x86: Add flags to event constraints

2013-04-01T15:15:04Z

This patch adds a flags field to each event constraint. It can be used to store event specific features which can then later be used by scheduling code or low-level x86 code. The flags are propagated into event->hw.flags during the get_event_constraint() call. They are cleared during the put_event_constraint() call. This mechanism is going to be used by the PEBS-LL patches. It avoids defining yet another table to hold event specific information. Signed-off-by: Stephane Eranian Cc: peterz@infradead.org Cc: ak@linux.intel.com Cc: jolsa@redhat.com Cc: namhyung.kim@lge.com Link: http://lkml.kernel.org/r/1359040242-8269-4-git-send-email-eranian@google.com Signed-off-by: Ingo Molnar Signed-off-by: Arnaldo Carvalho de Melo

perf/x86: Improve sysfs event mapping with event string

2013-03-26T20:36:45Z

This patch extends Jiri's changes to make generic events mapping visible via sysfs. The patch extends the mechanism to non-generic events by allowing the mappings to be hardcoded in strings. This mechanism will be used by the PEBS-LL patch later on. Signed-off-by: Stephane Eranian Cc: peterz@infradead.org Cc: ak@linux.intel.com Cc: acme@redhat.com Cc: jolsa@redhat.com Cc: namhyung.kim@lge.com Link: http://lkml.kernel.org/r/1359040242-8269-3-git-send-email-eranian@google.com Signed-off-by: Ingo Molnar [ fixed up conflict with 2663960 "perf: Make EVENT_ATTR global" ] Signed-off-by: Arnaldo Carvalho de Melo

perf,x86: fix link failure for non-Intel configs

2013-03-17T22:59:15Z

Commit 1d9d8639c063 ("perf,x86: fix kernel crash with PEBS/BTS after suspend/resume") introduces a link failure since perf_restore_debug_store() is only defined for CONFIG_CPU_SUP_INTEL: arch/x86/power/built-in.o: In function `restore_processor_state': (.text+0x45c): undefined reference to `perf_restore_debug_store' Fix it by defining the dummy function appropriately. Signed-off-by: David Rientjes Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds