From: Adrian Hunter Date: Thu, 30 Oct 2014 14:09:42 +0000 (+0200) Subject: perf tools: Add a thread stack for synthesizing call chains X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=00447ccdf3335ea467841fc3c7d65ffd30748895;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git perf tools: Add a thread stack for synthesizing call chains Add a thread stack for synthesizing call chains from call and return events. Signed-off-by: Adrian Hunter Acked-by: Jiri Olsa Cc: David Ahern Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/r/1414678188-14946-2-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo --- diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf index 3caf7dab50e8..0ebcc4ad0244 100644 --- a/tools/perf/Makefile.perf +++ b/tools/perf/Makefile.perf @@ -317,6 +317,7 @@ LIB_H += ui/util.h LIB_H += ui/ui.h LIB_H += util/data.h LIB_H += util/kvm-stat.h +LIB_H += util/thread-stack.h LIB_OBJS += $(OUTPUT)util/abspath.o LIB_OBJS += $(OUTPUT)util/alias.o @@ -394,6 +395,7 @@ LIB_OBJS += $(OUTPUT)util/srcline.o LIB_OBJS += $(OUTPUT)util/data.o LIB_OBJS += $(OUTPUT)util/tsc.o LIB_OBJS += $(OUTPUT)util/cloexec.o +LIB_OBJS += $(OUTPUT)util/thread-stack.o LIB_OBJS += $(OUTPUT)ui/setup.o LIB_OBJS += $(OUTPUT)ui/helpline.o diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h index 8c7fe9d64e79..7be389735402 100644 --- a/tools/perf/util/event.h +++ b/tools/perf/util/event.h @@ -143,6 +143,32 @@ struct branch_stack { struct branch_entry entries[0]; }; +enum { + PERF_IP_FLAG_BRANCH = 1ULL << 0, + PERF_IP_FLAG_CALL = 1ULL << 1, + PERF_IP_FLAG_RETURN = 1ULL << 2, + PERF_IP_FLAG_CONDITIONAL = 1ULL << 3, + PERF_IP_FLAG_SYSCALLRET = 1ULL << 4, + PERF_IP_FLAG_ASYNC = 1ULL << 5, + PERF_IP_FLAG_INTERRUPT = 1ULL << 6, + PERF_IP_FLAG_TX_ABORT = 1ULL << 7, + PERF_IP_FLAG_TRACE_BEGIN = 1ULL << 8, + PERF_IP_FLAG_TRACE_END = 1ULL << 9, + PERF_IP_FLAG_IN_TX = 1ULL << 10, +}; + +#define PERF_BRANCH_MASK (\ + PERF_IP_FLAG_BRANCH |\ + PERF_IP_FLAG_CALL |\ + PERF_IP_FLAG_RETURN |\ + PERF_IP_FLAG_CONDITIONAL |\ + PERF_IP_FLAG_SYSCALLRET |\ + PERF_IP_FLAG_ASYNC |\ + PERF_IP_FLAG_INTERRUPT |\ + PERF_IP_FLAG_TX_ABORT |\ + PERF_IP_FLAG_TRACE_BEGIN |\ + PERF_IP_FLAG_TRACE_END) + struct perf_sample { u64 ip; u32 pid, tid; diff --git a/tools/perf/util/thread-stack.c b/tools/perf/util/thread-stack.c new file mode 100644 index 000000000000..85b60d2e738f --- /dev/null +++ b/tools/perf/util/thread-stack.c @@ -0,0 +1,172 @@ +/* + * thread-stack.c: Synthesize a thread's stack using call / return events + * Copyright (c) 2014, Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + */ + +#include "thread.h" +#include "event.h" +#include "util.h" +#include "debug.h" +#include "thread-stack.h" + +#define STACK_GROWTH 4096 + +struct thread_stack_entry { + u64 ret_addr; +}; + +struct thread_stack { + struct thread_stack_entry *stack; + size_t cnt; + size_t sz; + u64 trace_nr; +}; + +static int thread_stack__grow(struct thread_stack *ts) +{ + struct thread_stack_entry *new_stack; + size_t sz, new_sz; + + new_sz = ts->sz + STACK_GROWTH; + sz = new_sz * sizeof(struct thread_stack_entry); + + new_stack = realloc(ts->stack, sz); + if (!new_stack) + return -ENOMEM; + + ts->stack = new_stack; + ts->sz = new_sz; + + return 0; +} + +static struct thread_stack *thread_stack__new(void) +{ + struct thread_stack *ts; + + ts = zalloc(sizeof(struct thread_stack)); + if (!ts) + return NULL; + + if (thread_stack__grow(ts)) { + free(ts); + return NULL; + } + + return ts; +} + +static int thread_stack__push(struct thread_stack *ts, u64 ret_addr) +{ + int err = 0; + + if (ts->cnt == ts->sz) { + err = thread_stack__grow(ts); + if (err) { + pr_warning("Out of memory: discarding thread stack\n"); + ts->cnt = 0; + } + } + + ts->stack[ts->cnt++].ret_addr = ret_addr; + + return err; +} + +static void thread_stack__pop(struct thread_stack *ts, u64 ret_addr) +{ + size_t i; + + /* + * In some cases there may be functions which are not seen to return. + * For example when setjmp / longjmp has been used. Or the perf context + * switch in the kernel which doesn't stop and start tracing in exactly + * the same code path. When that happens the return address will be + * further down the stack. If the return address is not found at all, + * we assume the opposite (i.e. this is a return for a call that wasn't + * seen for some reason) and leave the stack alone. + */ + for (i = ts->cnt; i; ) { + if (ts->stack[--i].ret_addr == ret_addr) { + ts->cnt = i; + return; + } + } +} + +int thread_stack__event(struct thread *thread, u32 flags, u64 from_ip, + u64 to_ip, u16 insn_len, u64 trace_nr) +{ + if (!thread) + return -EINVAL; + + if (!thread->ts) { + thread->ts = thread_stack__new(); + if (!thread->ts) { + pr_warning("Out of memory: no thread stack\n"); + return -ENOMEM; + } + thread->ts->trace_nr = trace_nr; + } + + /* + * When the trace is discontinuous, the trace_nr changes. In that case + * the stack might be completely invalid. Better to report nothing than + * to report something misleading, so reset the stack count to zero. + */ + if (trace_nr != thread->ts->trace_nr) { + thread->ts->trace_nr = trace_nr; + thread->ts->cnt = 0; + } + + if (flags & PERF_IP_FLAG_CALL) { + u64 ret_addr; + + if (!to_ip) + return 0; + ret_addr = from_ip + insn_len; + if (ret_addr == to_ip) + return 0; /* Zero-length calls are excluded */ + return thread_stack__push(thread->ts, ret_addr); + } else if (flags & PERF_IP_FLAG_RETURN) { + if (!from_ip) + return 0; + thread_stack__pop(thread->ts, to_ip); + } + + return 0; +} + +void thread_stack__free(struct thread *thread) +{ + if (thread->ts) { + zfree(&thread->ts->stack); + zfree(&thread->ts); + } +} + +void thread_stack__sample(struct thread *thread, struct ip_callchain *chain, + size_t sz, u64 ip) +{ + size_t i; + + if (!thread || !thread->ts) + chain->nr = 1; + else + chain->nr = min(sz, thread->ts->cnt + 1); + + chain->ips[0] = ip; + + for (i = 1; i < chain->nr; i++) + chain->ips[i] = thread->ts->stack[thread->ts->cnt - i].ret_addr; +} diff --git a/tools/perf/util/thread-stack.h b/tools/perf/util/thread-stack.h new file mode 100644 index 000000000000..7c41579aec74 --- /dev/null +++ b/tools/perf/util/thread-stack.h @@ -0,0 +1,32 @@ +/* + * thread-stack.h: Synthesize a thread's stack using call / return events + * Copyright (c) 2014, Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + */ + +#ifndef __PERF_THREAD_STACK_H +#define __PERF_THREAD_STACK_H + +#include + +#include + +struct thread; +struct ip_callchain; + +int thread_stack__event(struct thread *thread, u32 flags, u64 from_ip, + u64 to_ip, u16 insn_len, u64 trace_nr); +void thread_stack__sample(struct thread *thread, struct ip_callchain *chain, + size_t sz, u64 ip); +void thread_stack__free(struct thread *thread); + +#endif diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c index bf5bf858b7f6..a2157f0ef1df 100644 --- a/tools/perf/util/thread.c +++ b/tools/perf/util/thread.c @@ -4,6 +4,7 @@ #include #include "session.h" #include "thread.h" +#include "thread-stack.h" #include "util.h" #include "debug.h" #include "comm.h" @@ -66,6 +67,8 @@ void thread__delete(struct thread *thread) { struct comm *comm, *tmp; + thread_stack__free(thread); + if (thread->mg) { map_groups__put(thread->mg); thread->mg = NULL; diff --git a/tools/perf/util/thread.h b/tools/perf/util/thread.h index d34cf5c0d0d9..160fd066a7d1 100644 --- a/tools/perf/util/thread.h +++ b/tools/perf/util/thread.h @@ -8,6 +8,8 @@ #include "symbol.h" #include +struct thread_stack; + struct thread { union { struct rb_node rb_node; @@ -26,6 +28,7 @@ struct thread { u64 db_id; void *priv; + struct thread_stack *ts; }; struct machine;