From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757905Ab2GKOPM (ORCPT ); Wed, 11 Jul 2012 10:15:12 -0400 Received: from mailhub.sw.ru ([195.214.232.25]:17604 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755343Ab2GKOPJ (ORCPT ); Wed, 11 Jul 2012 10:15:09 -0400 From: Andrew Vagin To: Peter Zijlstra Cc: linux-kernel@vger.kernel.org, Ingo Molnar , Steven Rostedt , Paul Mackerras , Arnaldo Carvalho de Melo , Arun Sharma , Andrew Vagin Subject: [PATCH] trace: add ability to set a target task for events (v2) Date: Wed, 11 Jul 2012 18:14:58 +0400 Message-Id: <1342016098-213063-1-git-send-email-avagin@openvz.org> X-Mailer: git-send-email 1.7.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org A few events are interesting not only for a current task. For example, sched_stat_* are interesting for a task, which wake up. For this reason, it will be good, if such events will be delivered to a target task too. Now a target task can be set by using __perf_task(). The original idea and a draft patch belongs to Peter Zijlstra. I need this events for profiling sleep times. sched_switch is used for getting callchains and sched_stat_* is used for getting time periods. This events are combined in user space, then it can be analized by perf tools. v2: Disallow cross-task user callchains Inspired-by: Peter Zijlstra Cc: Ingo Molnar Cc: Steven Rostedt Cc: Paul Mackerras Cc: Arnaldo Carvalho de Melo Cc: Steven Rostedt Cc: Arun Sharma Signed-off-by: Andrew Vagin --- include/linux/ftrace_event.h | 5 +++-- include/linux/perf_event.h | 3 ++- include/trace/events/sched.h | 4 ++++ include/trace/ftrace.h | 6 +++++- kernel/events/callchain.c | 9 ++++++++- kernel/events/core.c | 28 ++++++++++++++++++++++++++-- kernel/events/internal.h | 3 ++- kernel/trace/trace_event_perf.c | 2 +- kernel/trace/trace_kprobe.c | 6 ++++-- kernel/trace/trace_syscalls.c | 4 ++-- 10 files changed, 57 insertions(+), 13 deletions(-) diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h index 176a939..55b96e3 100644 --- a/include/linux/ftrace_event.h +++ b/include/linux/ftrace_event.h @@ -303,9 +303,10 @@ extern void *perf_trace_buf_prepare(int size, unsigned short type, static inline void perf_trace_buf_submit(void *raw_data, int size, int rctx, u64 addr, - u64 count, struct pt_regs *regs, void *head) + u64 count, struct pt_regs *regs, void *head, + struct task_struct *task) { - perf_tp_event(addr, count, raw_data, size, regs, head, rctx); + perf_tp_event(addr, count, raw_data, size, regs, head, rctx, task); } #endif diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 45db49f..14acc5d 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -1269,7 +1269,8 @@ static inline bool perf_paranoid_kernel(void) extern void perf_event_init(void); extern void perf_tp_event(u64 addr, u64 count, void *record, int entry_size, struct pt_regs *regs, - struct hlist_head *head, int rctx); + struct hlist_head *head, int rctx, + struct task_struct *task); extern void perf_bp_event(struct perf_event *event, void *data); #ifndef perf_misc_flags diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h index ea7a203..5a8671e 100644 --- a/include/trace/events/sched.h +++ b/include/trace/events/sched.h @@ -73,6 +73,9 @@ DECLARE_EVENT_CLASS(sched_wakeup_template, __entry->prio = p->prio; __entry->success = success; __entry->target_cpu = task_cpu(p); + ) + TP_perf_assign( + __perf_task(p); ), TP_printk("comm=%s pid=%d prio=%d success=%d target_cpu=%03d", @@ -325,6 +328,7 @@ DECLARE_EVENT_CLASS(sched_stat_template, ) TP_perf_assign( __perf_count(delay); + __perf_task(tsk); ), TP_printk("comm=%s pid=%d delay=%Lu [ns]", diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h index 7697249..db14daf 100644 --- a/include/trace/ftrace.h +++ b/include/trace/ftrace.h @@ -711,6 +711,9 @@ __attribute__((section("_ftrace_events"))) *__event_##call = &event_##call #undef __perf_count #define __perf_count(c) __count = (c) +#undef __perf_task +#define __perf_task(t) __task = (t) + #undef TP_perf_assign #define TP_perf_assign(args...) args @@ -724,6 +727,7 @@ perf_trace_##call(void *__data, proto) \ struct ftrace_raw_##call *entry; \ struct pt_regs __regs; \ u64 __addr = 0, __count = 1; \ + struct task_struct *__task = NULL; \ struct hlist_head *head; \ int __entry_size; \ int __data_size; \ @@ -751,7 +755,7 @@ perf_trace_##call(void *__data, proto) \ \ head = this_cpu_ptr(event_call->perf_events); \ perf_trace_buf_submit(entry, __entry_size, rctx, __addr, \ - __count, &__regs, head); \ + __count, &__regs, head, __task); \ } /* diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c index 6581a04..98d4597 100644 --- a/kernel/events/callchain.c +++ b/kernel/events/callchain.c @@ -153,7 +153,8 @@ put_callchain_entry(int rctx) put_recursion_context(__get_cpu_var(callchain_recursion), rctx); } -struct perf_callchain_entry *perf_callchain(struct pt_regs *regs) +struct perf_callchain_entry * +perf_callchain(struct perf_event *event, struct pt_regs *regs) { int rctx; struct perf_callchain_entry *entry; @@ -178,6 +179,12 @@ struct perf_callchain_entry *perf_callchain(struct pt_regs *regs) } if (regs) { + /* + * Disallow cross-task user callchains. + */ + if (event->ctx->task && event->ctx->task != current) + goto exit_put; + perf_callchain_store(entry, PERF_CONTEXT_USER); perf_callchain_user(entry, regs); } diff --git a/kernel/events/core.c b/kernel/events/core.c index d7d71d6..1ebee0a 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -4037,7 +4037,7 @@ void perf_prepare_sample(struct perf_event_header *header, if (sample_type & PERF_SAMPLE_CALLCHAIN) { int size = 1; - data->callchain = perf_callchain(regs); + data->callchain = perf_callchain(event, regs); if (data->callchain) size += data->callchain->nr; @@ -5207,7 +5207,8 @@ static int perf_tp_event_match(struct perf_event *event, } void perf_tp_event(u64 addr, u64 count, void *record, int entry_size, - struct pt_regs *regs, struct hlist_head *head, int rctx) + struct pt_regs *regs, struct hlist_head *head, int rctx, + struct task_struct *task) { struct perf_sample_data data; struct perf_event *event; @@ -5226,6 +5227,29 @@ void perf_tp_event(u64 addr, u64 count, void *record, int entry_size, perf_swevent_event(event, count, &data, regs); } + /* + * If we got specified a target task, also iterate its context and + * deliver this event there too. + */ + if (task && task != current) { + struct perf_event_context *ctx; + struct trace_entry *entry = record; + + rcu_read_lock(); + ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); + if (!ctx) + goto unlock; + + list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { + if (entry->type != event->attr.config) + continue; + if (perf_tp_event_match(event, &data, regs)) + perf_swevent_event(event, count, &data, regs); + } +unlock: + rcu_read_unlock(); + } + perf_swevent_put_recursion_context(rctx); } EXPORT_SYMBOL_GPL(perf_tp_event); diff --git a/kernel/events/internal.h b/kernel/events/internal.h index b0b107f..a096c19 100644 --- a/kernel/events/internal.h +++ b/kernel/events/internal.h @@ -101,7 +101,8 @@ __output_copy(struct perf_output_handle *handle, } /* Callchain handling */ -extern struct perf_callchain_entry *perf_callchain(struct pt_regs *regs); +extern struct perf_callchain_entry * +perf_callchain(struct perf_event *event, struct pt_regs *regs); extern int get_callchain_buffers(void); extern void put_callchain_buffers(void); diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c index fee3752..8a6d2ee 100644 --- a/kernel/trace/trace_event_perf.c +++ b/kernel/trace/trace_event_perf.c @@ -281,7 +281,7 @@ perf_ftrace_function_call(unsigned long ip, unsigned long parent_ip) head = this_cpu_ptr(event_function.perf_events); perf_trace_buf_submit(entry, ENTRY_SIZE, rctx, 0, - 1, ®s, head); + 1, ®s, head, NULL); #undef ENTRY_SIZE } diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index b31d3d5..1a21170 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -1002,7 +1002,8 @@ static __kprobes void kprobe_perf_func(struct kprobe *kp, store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); head = this_cpu_ptr(call->perf_events); - perf_trace_buf_submit(entry, size, rctx, entry->ip, 1, regs, head); + perf_trace_buf_submit(entry, size, rctx, + entry->ip, 1, regs, head, NULL); } /* Kretprobe profile handler */ @@ -1033,7 +1034,8 @@ static __kprobes void kretprobe_perf_func(struct kretprobe_instance *ri, store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); head = this_cpu_ptr(call->perf_events); - perf_trace_buf_submit(entry, size, rctx, entry->ret_ip, 1, regs, head); + perf_trace_buf_submit(entry, size, rctx, + entry->ret_ip, 1, regs, head, NULL); } #endif /* CONFIG_PERF_EVENTS */ diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index 96fc733..60e4d78 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -532,7 +532,7 @@ static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id) (unsigned long *)&rec->args); head = this_cpu_ptr(sys_data->enter_event->perf_events); - perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head); + perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL); } int perf_sysenter_enable(struct ftrace_event_call *call) @@ -608,7 +608,7 @@ static void perf_syscall_exit(void *ignore, struct pt_regs *regs, long ret) rec->ret = syscall_get_return_value(current, regs); head = this_cpu_ptr(sys_data->exit_event->perf_events); - perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head); + perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL); } int perf_sysexit_enable(struct ftrace_event_call *call) -- 1.7.1