From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935287AbaGYUHj (ORCPT ); Fri, 25 Jul 2014 16:07:39 -0400 Received: from relais.videotron.ca ([24.201.245.36]:13726 "EHLO relais.videotron.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932080AbaGYUHg (ORCPT ); Fri, 25 Jul 2014 16:07:36 -0400 Content-transfer-encoding: 7BIT From: Nicolas Pitre To: Steven Rostedt , Ingo Molnar Cc: Daniel Lezcano , Russell King - ARM Linux , Catalin Marinas , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linaro-kernel@lists.linaro.org Subject: [PATCH v2 2/5] tracepoint: add generic tracepoint definitions for IPI tracing Date: Fri, 25 Jul 2014 16:05:30 -0400 Message-id: <1406318733-26754-3-git-send-email-nicolas.pitre@linaro.org> X-Mailer: git-send-email 1.8.4.108.g55ea5f6 In-reply-to: <1406318733-26754-1-git-send-email-nicolas.pitre@linaro.org> References: <1406318733-26754-1-git-send-email-nicolas.pitre@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The Inter Processor Interrupt is used to make another processor do a specific action such as rescheduling tasks, signal a timer event or execute something in another CPU's context. IRQs are already traceable but IPIs were not. Tracing them is useful for monitoring IPI latency, or to verify when they are the source of CPU wake-ups with power management implications. Three trace hooks are defined: ipi_raise, ipi_entry and ipi_exit. To make them portable, a string is used to identify them and correlate related events. Additionally, ipi_raise records a bitmask representing targeted CPUs. Signed-off-by: Nicolas Pitre Acked-by: Steven Rostedt Acked-by: Daniel Lezcano --- include/trace/events/ipi.h | 89 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 89 insertions(+) create mode 100644 include/trace/events/ipi.h diff --git a/include/trace/events/ipi.h b/include/trace/events/ipi.h new file mode 100644 index 0000000000..834a7362a6 --- /dev/null +++ b/include/trace/events/ipi.h @@ -0,0 +1,89 @@ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM ipi + +#if !defined(_TRACE_IPI_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_IPI_H + +#include + +/** + * ipi_raise - called when a smp cross call is made + * + * @mask: mask of recipient CPUs for the IPI + * @reason: string identifying the IPI purpose + * + * It is necessary for @reason to be a static string declared with + * __tracepoint_string. + */ +TRACE_EVENT(ipi_raise, + + TP_PROTO(const struct cpumask *mask, const char *reason), + + TP_ARGS(mask, reason), + + TP_STRUCT__entry( + __bitmask(target_cpus, nr_cpumask_bits) + __field(const char *, reason) + ), + + TP_fast_assign( + __assign_bitmask(target_cpus, cpumask_bits(mask), nr_cpumask_bits); + __entry->reason = reason; + ), + + TP_printk("target_mask=%s (%s)", __get_bitmask(target_cpus), __entry->reason) +); + +DECLARE_EVENT_CLASS(ipi_handler, + + TP_PROTO(const char *reason), + + TP_ARGS(reason), + + TP_STRUCT__entry( + __field(const char *, reason) + ), + + TP_fast_assign( + __entry->reason = reason; + ), + + TP_printk("(%s)", __entry->reason) +); + +/** + * ipi_entry - called immediately before the IPI handler + * + * @reason: string identifying the IPI purpose + * + * It is necessary for @reason to be a static string declared with + * __tracepoint_string, ideally the same as used with trace_ipi_raise + * for that IPI. + */ +DEFINE_EVENT(ipi_handler, ipi_entry, + + TP_PROTO(const char *reason), + + TP_ARGS(reason) +); + +/** + * ipi_exit - called immediately after the IPI handler returns + * + * @reason: string identifying the IPI purpose + * + * It is necessary for @reason to be a static string declared with + * __tracepoint_string, ideally the same as used with trace_ipi_raise for + * that IPI. + */ +DEFINE_EVENT(ipi_handler, ipi_exit, + + TP_PROTO(const char *reason), + + TP_ARGS(reason) +); + +#endif /* _TRACE_IPI_H */ + +/* This part must be outside protection */ +#include -- 1.8.4.108.g55ea5f6