On Thu, Jun 28, 2018 at 11:21:42AM -0700, Joel Fernandes wrote: > From: "Joel Fernandes (Google)" <joel@xxxxxxxxxxxxxxxxx> > > This is a posting of v9 preempt/irq tracepoint clean up series rebased > onto v4.18-rc2. No changes in the series, just a rebase + repost. > > All patches have a Reviewed-by tags now from reviewers. This series has > been well tested and is a simplification/refactoring of existing code, > along with giving a speed-up for tracepoints using the rcu-idle API. > With this our users will find it easier to use tools depending on > existing preempt tracepoints since it simplifies the configuration for > them. Steve, all patches of this tracing series have been reviewed and/or acked and there haven't been additional changes for a couple of reposts. Are you Ok with it? Thanks, -Joel > Future enhancements/fixes I am developing for preempt-off tracer will > depend on these patches, so I suggest prioritizing these well reviewed > and tested patches for that reason as well. > > Introduction to the series: > The preempt/irq tracepoints exist but not everything in the kernel is using it > whenever they need to be notified that a preempt disable/enable or an irq > disable/enable has occurred. This makes things not work simultaneously (for > example, only either lockdep or irqsoff trace-events can be used at a time). > > This is particularly painful to deal with, since turning on lockdep breaks > tracers that install probes on IRQ events, such as the BCC atomic critical > section tracer [1]. This constraint also makes it impossible to use synthetic > events to trace irqsoff sections with lockdep simulataneously turned on. > > This series solves that, and also results in a nice clean up of relevant parts > of the kernel. Several ifdefs are simpler, and the design is more unified and > better. Also as a result of this, we also speeded performance all rcuidle > tracepoints since their handling is simpler. > > [1] https://github.com/iovisor/bcc/blob/master/tools/criticalstat_example.txt > > v8->v9: > - Small style changes to tracepoint code (Mathieu) > - Minor style fix to use PTR_ERR_OR_ZERO (0-day bot) > - Minor fix to test_atomic_sections to use unsigned long. > - Added Namhyung's, Mathieu's Reviewed-by to some patches. > - Added Acks from Matsami > > v7->v8: > - Refactored irqsoff tracer probe defines (Namhyung) > > v6->v7: > - Added a module to simulate an atomic section, a kselftest to load and > and trigger it which verifies the preempt-tracer and this series. > > - Fixed a new warning after I rebased in early boot, this is because > early_boot_irqs_disabled was set too early, I moved it after the lockdep > initialization. > > - added back the softirq fix since it appears it wasn't picked up. > > - Ran Ingo's locking API selftest suite which are passing with this > series. > > - Mathieu suggested ifdef'ing the tracepoint_synchronize_unregister > function incase tracepoints aren't enabled, did that. > > > Joel Fernandes (Google) (6): > srcu: Add notrace variant of srcu_dereference > trace/irqsoff: Split reset into separate functions > tracepoint: Make rcuidle tracepoint callers use SRCU > tracing: Centralize preemptirq tracepoints and unify their usage > lib: Add module to simulate atomic sections for testing preemptoff > tracers > kselftests: Add tests for the preemptoff and irqsoff tracers > > Paul McKenney (1): > srcu: Add notrace variants of srcu_read_{lock,unlock} > > include/linux/ftrace.h | 11 +- > include/linux/irqflags.h | 11 +- > include/linux/lockdep.h | 8 +- > include/linux/preempt.h | 2 +- > include/linux/srcu.h | 22 ++ > include/linux/tracepoint.h | 49 +++- > include/trace/events/preemptirq.h | 23 +- > init/main.c | 5 +- > kernel/locking/lockdep.c | 35 +-- > kernel/sched/core.c | 2 +- > kernel/trace/Kconfig | 22 +- > kernel/trace/Makefile | 2 +- > kernel/trace/trace_irqsoff.c | 253 ++++++------------ > kernel/trace/trace_preemptirq.c | 71 +++++ > kernel/tracepoint.c | 16 +- > lib/Kconfig.debug | 8 + > lib/Makefile | 1 + > lib/test_atomic_sections.c | 77 ++++++ > tools/testing/selftests/ftrace/config | 3 + > .../test.d/preemptirq/irqsoff_tracer.tc | 73 +++++ > 20 files changed, 453 insertions(+), 241 deletions(-) > create mode 100644 kernel/trace/trace_preemptirq.c > create mode 100644 lib/test_atomic_sections.c > create mode 100644 tools/testing/selftests/ftrace/test.d/preemptirq/irqsoff_tracer.tc > > -- > 2.18.0.rc2.346.g013aa6912e-goog > > -- To unsubscribe from this list: send the line "unsubscribe linux-kselftest" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
