100447ccdSAdrian Hunter /* 200447ccdSAdrian Hunter * thread-stack.c: Synthesize a thread's stack using call / return events 300447ccdSAdrian Hunter * Copyright (c) 2014, Intel Corporation. 400447ccdSAdrian Hunter * 500447ccdSAdrian Hunter * This program is free software; you can redistribute it and/or modify it 600447ccdSAdrian Hunter * under the terms and conditions of the GNU General Public License, 700447ccdSAdrian Hunter * version 2, as published by the Free Software Foundation. 800447ccdSAdrian Hunter * 900447ccdSAdrian Hunter * This program is distributed in the hope it will be useful, but WITHOUT 1000447ccdSAdrian Hunter * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 1100447ccdSAdrian Hunter * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 1200447ccdSAdrian Hunter * more details. 1300447ccdSAdrian Hunter * 1400447ccdSAdrian Hunter */ 1500447ccdSAdrian Hunter 1692a9e4f7SAdrian Hunter #include <linux/rbtree.h> 1792a9e4f7SAdrian Hunter #include <linux/list.h> 18a43783aeSArnaldo Carvalho de Melo #include <errno.h> 1900447ccdSAdrian Hunter #include "thread.h" 2000447ccdSAdrian Hunter #include "event.h" 2192a9e4f7SAdrian Hunter #include "machine.h" 2200447ccdSAdrian Hunter #include "util.h" 2300447ccdSAdrian Hunter #include "debug.h" 2492a9e4f7SAdrian Hunter #include "symbol.h" 2592a9e4f7SAdrian Hunter #include "comm.h" 26451db126SChris Phlipot #include "call-path.h" 2700447ccdSAdrian Hunter #include "thread-stack.h" 2800447ccdSAdrian Hunter 2992a9e4f7SAdrian Hunter #define STACK_GROWTH 2048 3092a9e4f7SAdrian Hunter 3192a9e4f7SAdrian Hunter /** 3292a9e4f7SAdrian Hunter * struct thread_stack_entry - thread stack entry. 3392a9e4f7SAdrian Hunter * @ret_addr: return address 3492a9e4f7SAdrian Hunter * @timestamp: timestamp (if known) 3592a9e4f7SAdrian Hunter * @ref: external reference (e.g. db_id of sample) 3692a9e4f7SAdrian Hunter * @branch_count: the branch count when the entry was created 3792a9e4f7SAdrian Hunter * @cp: call path 3892a9e4f7SAdrian Hunter * @no_call: a 'call' was not seen 394d60e5e3SAdrian Hunter * @trace_end: a 'call' but trace ended 4092a9e4f7SAdrian Hunter */ 4192a9e4f7SAdrian Hunter struct thread_stack_entry { 4292a9e4f7SAdrian Hunter u64 ret_addr; 4392a9e4f7SAdrian Hunter u64 timestamp; 4492a9e4f7SAdrian Hunter u64 ref; 4592a9e4f7SAdrian Hunter u64 branch_count; 4692a9e4f7SAdrian Hunter struct call_path *cp; 4792a9e4f7SAdrian Hunter bool no_call; 484d60e5e3SAdrian Hunter bool trace_end; 4992a9e4f7SAdrian Hunter }; 5092a9e4f7SAdrian Hunter 5192a9e4f7SAdrian Hunter /** 5292a9e4f7SAdrian Hunter * struct thread_stack - thread stack constructed from 'call' and 'return' 5392a9e4f7SAdrian Hunter * branch samples. 5492a9e4f7SAdrian Hunter * @stack: array that holds the stack 5592a9e4f7SAdrian Hunter * @cnt: number of entries in the stack 5692a9e4f7SAdrian Hunter * @sz: current maximum stack size 5792a9e4f7SAdrian Hunter * @trace_nr: current trace number 5892a9e4f7SAdrian Hunter * @branch_count: running branch count 5992a9e4f7SAdrian Hunter * @kernel_start: kernel start address 6092a9e4f7SAdrian Hunter * @last_time: last timestamp 6192a9e4f7SAdrian Hunter * @crp: call/return processor 6292a9e4f7SAdrian Hunter * @comm: current comm 63f6060ac6SAdrian Hunter * @arr_sz: size of array if this is the first element of an array 6492a9e4f7SAdrian Hunter */ 6500447ccdSAdrian Hunter struct thread_stack { 6600447ccdSAdrian Hunter struct thread_stack_entry *stack; 6700447ccdSAdrian Hunter size_t cnt; 6800447ccdSAdrian Hunter size_t sz; 6900447ccdSAdrian Hunter u64 trace_nr; 7092a9e4f7SAdrian Hunter u64 branch_count; 7192a9e4f7SAdrian Hunter u64 kernel_start; 7292a9e4f7SAdrian Hunter u64 last_time; 7392a9e4f7SAdrian Hunter struct call_return_processor *crp; 7492a9e4f7SAdrian Hunter struct comm *comm; 75f6060ac6SAdrian Hunter unsigned int arr_sz; 7600447ccdSAdrian Hunter }; 7700447ccdSAdrian Hunter 7800447ccdSAdrian Hunter static int thread_stack__grow(struct thread_stack *ts) 7900447ccdSAdrian Hunter { 8000447ccdSAdrian Hunter struct thread_stack_entry *new_stack; 8100447ccdSAdrian Hunter size_t sz, new_sz; 8200447ccdSAdrian Hunter 8300447ccdSAdrian Hunter new_sz = ts->sz + STACK_GROWTH; 8400447ccdSAdrian Hunter sz = new_sz * sizeof(struct thread_stack_entry); 8500447ccdSAdrian Hunter 8600447ccdSAdrian Hunter new_stack = realloc(ts->stack, sz); 8700447ccdSAdrian Hunter if (!new_stack) 8800447ccdSAdrian Hunter return -ENOMEM; 8900447ccdSAdrian Hunter 9000447ccdSAdrian Hunter ts->stack = new_stack; 9100447ccdSAdrian Hunter ts->sz = new_sz; 9200447ccdSAdrian Hunter 9300447ccdSAdrian Hunter return 0; 9400447ccdSAdrian Hunter } 9500447ccdSAdrian Hunter 962e9e8688SAdrian Hunter static int thread_stack__init(struct thread_stack *ts, struct thread *thread, 972e9e8688SAdrian Hunter struct call_return_processor *crp) 982e9e8688SAdrian Hunter { 992e9e8688SAdrian Hunter int err; 1002e9e8688SAdrian Hunter 1012e9e8688SAdrian Hunter err = thread_stack__grow(ts); 1022e9e8688SAdrian Hunter if (err) 1032e9e8688SAdrian Hunter return err; 1042e9e8688SAdrian Hunter 1052e9e8688SAdrian Hunter if (thread->mg && thread->mg->machine) 1062e9e8688SAdrian Hunter ts->kernel_start = machine__kernel_start(thread->mg->machine); 1072e9e8688SAdrian Hunter else 1082e9e8688SAdrian Hunter ts->kernel_start = 1ULL << 63; 1092e9e8688SAdrian Hunter ts->crp = crp; 1102e9e8688SAdrian Hunter 1112e9e8688SAdrian Hunter return 0; 1122e9e8688SAdrian Hunter } 1132e9e8688SAdrian Hunter 11492a9e4f7SAdrian Hunter static struct thread_stack *thread_stack__new(struct thread *thread, 11592a9e4f7SAdrian Hunter struct call_return_processor *crp) 11600447ccdSAdrian Hunter { 11700447ccdSAdrian Hunter struct thread_stack *ts; 11800447ccdSAdrian Hunter 11900447ccdSAdrian Hunter ts = zalloc(sizeof(struct thread_stack)); 12000447ccdSAdrian Hunter if (!ts) 12100447ccdSAdrian Hunter return NULL; 12200447ccdSAdrian Hunter 123f6060ac6SAdrian Hunter ts->arr_sz = 1; 124f6060ac6SAdrian Hunter 1252e9e8688SAdrian Hunter if (thread_stack__init(ts, thread, crp)) { 12600447ccdSAdrian Hunter free(ts); 12700447ccdSAdrian Hunter return NULL; 12800447ccdSAdrian Hunter } 12900447ccdSAdrian Hunter 130bd8e68acSAdrian Hunter thread->ts = ts; 131bd8e68acSAdrian Hunter 13200447ccdSAdrian Hunter return ts; 13300447ccdSAdrian Hunter } 13400447ccdSAdrian Hunter 135bd8e68acSAdrian Hunter static inline struct thread_stack *thread__stack(struct thread *thread) 136bd8e68acSAdrian Hunter { 137bd8e68acSAdrian Hunter return thread ? thread->ts : NULL; 138bd8e68acSAdrian Hunter } 139bd8e68acSAdrian Hunter 1404d60e5e3SAdrian Hunter static int thread_stack__push(struct thread_stack *ts, u64 ret_addr, 1414d60e5e3SAdrian Hunter bool trace_end) 14200447ccdSAdrian Hunter { 14300447ccdSAdrian Hunter int err = 0; 14400447ccdSAdrian Hunter 14500447ccdSAdrian Hunter if (ts->cnt == ts->sz) { 14600447ccdSAdrian Hunter err = thread_stack__grow(ts); 14700447ccdSAdrian Hunter if (err) { 14800447ccdSAdrian Hunter pr_warning("Out of memory: discarding thread stack\n"); 14900447ccdSAdrian Hunter ts->cnt = 0; 15000447ccdSAdrian Hunter } 15100447ccdSAdrian Hunter } 15200447ccdSAdrian Hunter 1534d60e5e3SAdrian Hunter ts->stack[ts->cnt].trace_end = trace_end; 15400447ccdSAdrian Hunter ts->stack[ts->cnt++].ret_addr = ret_addr; 15500447ccdSAdrian Hunter 15600447ccdSAdrian Hunter return err; 15700447ccdSAdrian Hunter } 15800447ccdSAdrian Hunter 15900447ccdSAdrian Hunter static void thread_stack__pop(struct thread_stack *ts, u64 ret_addr) 16000447ccdSAdrian Hunter { 16100447ccdSAdrian Hunter size_t i; 16200447ccdSAdrian Hunter 16300447ccdSAdrian Hunter /* 16400447ccdSAdrian Hunter * In some cases there may be functions which are not seen to return. 16500447ccdSAdrian Hunter * For example when setjmp / longjmp has been used. Or the perf context 16600447ccdSAdrian Hunter * switch in the kernel which doesn't stop and start tracing in exactly 16700447ccdSAdrian Hunter * the same code path. When that happens the return address will be 16800447ccdSAdrian Hunter * further down the stack. If the return address is not found at all, 16900447ccdSAdrian Hunter * we assume the opposite (i.e. this is a return for a call that wasn't 17000447ccdSAdrian Hunter * seen for some reason) and leave the stack alone. 17100447ccdSAdrian Hunter */ 17200447ccdSAdrian Hunter for (i = ts->cnt; i; ) { 17300447ccdSAdrian Hunter if (ts->stack[--i].ret_addr == ret_addr) { 17400447ccdSAdrian Hunter ts->cnt = i; 17500447ccdSAdrian Hunter return; 17600447ccdSAdrian Hunter } 17700447ccdSAdrian Hunter } 17800447ccdSAdrian Hunter } 17900447ccdSAdrian Hunter 1804d60e5e3SAdrian Hunter static void thread_stack__pop_trace_end(struct thread_stack *ts) 1814d60e5e3SAdrian Hunter { 1824d60e5e3SAdrian Hunter size_t i; 1834d60e5e3SAdrian Hunter 1844d60e5e3SAdrian Hunter for (i = ts->cnt; i; ) { 1854d60e5e3SAdrian Hunter if (ts->stack[--i].trace_end) 1864d60e5e3SAdrian Hunter ts->cnt = i; 1874d60e5e3SAdrian Hunter else 1884d60e5e3SAdrian Hunter return; 1894d60e5e3SAdrian Hunter } 1904d60e5e3SAdrian Hunter } 1914d60e5e3SAdrian Hunter 19292a9e4f7SAdrian Hunter static bool thread_stack__in_kernel(struct thread_stack *ts) 19392a9e4f7SAdrian Hunter { 19492a9e4f7SAdrian Hunter if (!ts->cnt) 19592a9e4f7SAdrian Hunter return false; 19692a9e4f7SAdrian Hunter 19792a9e4f7SAdrian Hunter return ts->stack[ts->cnt - 1].cp->in_kernel; 19892a9e4f7SAdrian Hunter } 19992a9e4f7SAdrian Hunter 20092a9e4f7SAdrian Hunter static int thread_stack__call_return(struct thread *thread, 20192a9e4f7SAdrian Hunter struct thread_stack *ts, size_t idx, 20292a9e4f7SAdrian Hunter u64 timestamp, u64 ref, bool no_return) 20392a9e4f7SAdrian Hunter { 20492a9e4f7SAdrian Hunter struct call_return_processor *crp = ts->crp; 20592a9e4f7SAdrian Hunter struct thread_stack_entry *tse; 20692a9e4f7SAdrian Hunter struct call_return cr = { 20792a9e4f7SAdrian Hunter .thread = thread, 20892a9e4f7SAdrian Hunter .comm = ts->comm, 20992a9e4f7SAdrian Hunter .db_id = 0, 21092a9e4f7SAdrian Hunter }; 21192a9e4f7SAdrian Hunter 21292a9e4f7SAdrian Hunter tse = &ts->stack[idx]; 21392a9e4f7SAdrian Hunter cr.cp = tse->cp; 21492a9e4f7SAdrian Hunter cr.call_time = tse->timestamp; 21592a9e4f7SAdrian Hunter cr.return_time = timestamp; 21692a9e4f7SAdrian Hunter cr.branch_count = ts->branch_count - tse->branch_count; 21792a9e4f7SAdrian Hunter cr.call_ref = tse->ref; 21892a9e4f7SAdrian Hunter cr.return_ref = ref; 21992a9e4f7SAdrian Hunter if (tse->no_call) 22092a9e4f7SAdrian Hunter cr.flags |= CALL_RETURN_NO_CALL; 22192a9e4f7SAdrian Hunter if (no_return) 22292a9e4f7SAdrian Hunter cr.flags |= CALL_RETURN_NO_RETURN; 22392a9e4f7SAdrian Hunter 22492a9e4f7SAdrian Hunter return crp->process(&cr, crp->data); 22592a9e4f7SAdrian Hunter } 22692a9e4f7SAdrian Hunter 227a5499b37SAdrian Hunter static int __thread_stack__flush(struct thread *thread, struct thread_stack *ts) 22892a9e4f7SAdrian Hunter { 22992a9e4f7SAdrian Hunter struct call_return_processor *crp = ts->crp; 23092a9e4f7SAdrian Hunter int err; 23192a9e4f7SAdrian Hunter 23292a9e4f7SAdrian Hunter if (!crp) { 23392a9e4f7SAdrian Hunter ts->cnt = 0; 23492a9e4f7SAdrian Hunter return 0; 23592a9e4f7SAdrian Hunter } 23692a9e4f7SAdrian Hunter 23792a9e4f7SAdrian Hunter while (ts->cnt) { 23892a9e4f7SAdrian Hunter err = thread_stack__call_return(thread, ts, --ts->cnt, 23992a9e4f7SAdrian Hunter ts->last_time, 0, true); 24092a9e4f7SAdrian Hunter if (err) { 24192a9e4f7SAdrian Hunter pr_err("Error flushing thread stack!\n"); 24292a9e4f7SAdrian Hunter ts->cnt = 0; 24392a9e4f7SAdrian Hunter return err; 24492a9e4f7SAdrian Hunter } 24592a9e4f7SAdrian Hunter } 24692a9e4f7SAdrian Hunter 24792a9e4f7SAdrian Hunter return 0; 24892a9e4f7SAdrian Hunter } 24992a9e4f7SAdrian Hunter 250a5499b37SAdrian Hunter int thread_stack__flush(struct thread *thread) 251a5499b37SAdrian Hunter { 252bd8e68acSAdrian Hunter struct thread_stack *ts = thread->ts; 253f6060ac6SAdrian Hunter unsigned int pos; 254f6060ac6SAdrian Hunter int err = 0; 255bd8e68acSAdrian Hunter 256f6060ac6SAdrian Hunter if (ts) { 257f6060ac6SAdrian Hunter for (pos = 0; pos < ts->arr_sz; pos++) { 258f6060ac6SAdrian Hunter int ret = __thread_stack__flush(thread, ts + pos); 259a5499b37SAdrian Hunter 260f6060ac6SAdrian Hunter if (ret) 261f6060ac6SAdrian Hunter err = ret; 262f6060ac6SAdrian Hunter } 263f6060ac6SAdrian Hunter } 264f6060ac6SAdrian Hunter 265f6060ac6SAdrian Hunter return err; 266a5499b37SAdrian Hunter } 267a5499b37SAdrian Hunter 26800447ccdSAdrian Hunter int thread_stack__event(struct thread *thread, u32 flags, u64 from_ip, 26900447ccdSAdrian Hunter u64 to_ip, u16 insn_len, u64 trace_nr) 27000447ccdSAdrian Hunter { 271bd8e68acSAdrian Hunter struct thread_stack *ts = thread__stack(thread); 272bd8e68acSAdrian Hunter 27300447ccdSAdrian Hunter if (!thread) 27400447ccdSAdrian Hunter return -EINVAL; 27500447ccdSAdrian Hunter 276bd8e68acSAdrian Hunter if (!ts) { 277bd8e68acSAdrian Hunter ts = thread_stack__new(thread, NULL); 278bd8e68acSAdrian Hunter if (!ts) { 27900447ccdSAdrian Hunter pr_warning("Out of memory: no thread stack\n"); 28000447ccdSAdrian Hunter return -ENOMEM; 28100447ccdSAdrian Hunter } 282bd8e68acSAdrian Hunter ts->trace_nr = trace_nr; 28300447ccdSAdrian Hunter } 28400447ccdSAdrian Hunter 28500447ccdSAdrian Hunter /* 28600447ccdSAdrian Hunter * When the trace is discontinuous, the trace_nr changes. In that case 28700447ccdSAdrian Hunter * the stack might be completely invalid. Better to report nothing than 28892a9e4f7SAdrian Hunter * to report something misleading, so flush the stack. 28900447ccdSAdrian Hunter */ 290bd8e68acSAdrian Hunter if (trace_nr != ts->trace_nr) { 291bd8e68acSAdrian Hunter if (ts->trace_nr) 292bd8e68acSAdrian Hunter __thread_stack__flush(thread, ts); 293bd8e68acSAdrian Hunter ts->trace_nr = trace_nr; 29400447ccdSAdrian Hunter } 29500447ccdSAdrian Hunter 29692a9e4f7SAdrian Hunter /* Stop here if thread_stack__process() is in use */ 297bd8e68acSAdrian Hunter if (ts->crp) 29892a9e4f7SAdrian Hunter return 0; 29992a9e4f7SAdrian Hunter 30000447ccdSAdrian Hunter if (flags & PERF_IP_FLAG_CALL) { 30100447ccdSAdrian Hunter u64 ret_addr; 30200447ccdSAdrian Hunter 30300447ccdSAdrian Hunter if (!to_ip) 30400447ccdSAdrian Hunter return 0; 30500447ccdSAdrian Hunter ret_addr = from_ip + insn_len; 30600447ccdSAdrian Hunter if (ret_addr == to_ip) 30700447ccdSAdrian Hunter return 0; /* Zero-length calls are excluded */ 308bd8e68acSAdrian Hunter return thread_stack__push(ts, ret_addr, 3094d60e5e3SAdrian Hunter flags & PERF_IP_FLAG_TRACE_END); 3104d60e5e3SAdrian Hunter } else if (flags & PERF_IP_FLAG_TRACE_BEGIN) { 3114d60e5e3SAdrian Hunter /* 3124d60e5e3SAdrian Hunter * If the caller did not change the trace number (which would 3134d60e5e3SAdrian Hunter * have flushed the stack) then try to make sense of the stack. 3144d60e5e3SAdrian Hunter * Possibly, tracing began after returning to the current 3154d60e5e3SAdrian Hunter * address, so try to pop that. Also, do not expect a call made 3164d60e5e3SAdrian Hunter * when the trace ended, to return, so pop that. 3174d60e5e3SAdrian Hunter */ 318bd8e68acSAdrian Hunter thread_stack__pop(ts, to_ip); 319bd8e68acSAdrian Hunter thread_stack__pop_trace_end(ts); 3204d60e5e3SAdrian Hunter } else if ((flags & PERF_IP_FLAG_RETURN) && from_ip) { 321bd8e68acSAdrian Hunter thread_stack__pop(ts, to_ip); 32200447ccdSAdrian Hunter } 32300447ccdSAdrian Hunter 32400447ccdSAdrian Hunter return 0; 32500447ccdSAdrian Hunter } 32600447ccdSAdrian Hunter 32792a9e4f7SAdrian Hunter void thread_stack__set_trace_nr(struct thread *thread, u64 trace_nr) 32892a9e4f7SAdrian Hunter { 329bd8e68acSAdrian Hunter struct thread_stack *ts = thread__stack(thread); 330bd8e68acSAdrian Hunter 331bd8e68acSAdrian Hunter if (!ts) 33292a9e4f7SAdrian Hunter return; 33392a9e4f7SAdrian Hunter 334bd8e68acSAdrian Hunter if (trace_nr != ts->trace_nr) { 335bd8e68acSAdrian Hunter if (ts->trace_nr) 336bd8e68acSAdrian Hunter __thread_stack__flush(thread, ts); 337bd8e68acSAdrian Hunter ts->trace_nr = trace_nr; 33892a9e4f7SAdrian Hunter } 33992a9e4f7SAdrian Hunter } 34092a9e4f7SAdrian Hunter 341f6060ac6SAdrian Hunter static void __thread_stack__free(struct thread *thread, struct thread_stack *ts) 342f6060ac6SAdrian Hunter { 343f6060ac6SAdrian Hunter __thread_stack__flush(thread, ts); 344f6060ac6SAdrian Hunter zfree(&ts->stack); 345f6060ac6SAdrian Hunter } 346f6060ac6SAdrian Hunter 347f6060ac6SAdrian Hunter static void thread_stack__reset(struct thread *thread, struct thread_stack *ts) 348f6060ac6SAdrian Hunter { 349f6060ac6SAdrian Hunter unsigned int arr_sz = ts->arr_sz; 350f6060ac6SAdrian Hunter 351f6060ac6SAdrian Hunter __thread_stack__free(thread, ts); 352f6060ac6SAdrian Hunter memset(ts, 0, sizeof(*ts)); 353f6060ac6SAdrian Hunter ts->arr_sz = arr_sz; 354f6060ac6SAdrian Hunter } 355f6060ac6SAdrian Hunter 35600447ccdSAdrian Hunter void thread_stack__free(struct thread *thread) 35700447ccdSAdrian Hunter { 358bd8e68acSAdrian Hunter struct thread_stack *ts = thread->ts; 359f6060ac6SAdrian Hunter unsigned int pos; 360bd8e68acSAdrian Hunter 361bd8e68acSAdrian Hunter if (ts) { 362f6060ac6SAdrian Hunter for (pos = 0; pos < ts->arr_sz; pos++) 363f6060ac6SAdrian Hunter __thread_stack__free(thread, ts + pos); 36400447ccdSAdrian Hunter zfree(&thread->ts); 36500447ccdSAdrian Hunter } 36600447ccdSAdrian Hunter } 36700447ccdSAdrian Hunter 36824248306SAdrian Hunter static inline u64 callchain_context(u64 ip, u64 kernel_start) 36900447ccdSAdrian Hunter { 37024248306SAdrian Hunter return ip < kernel_start ? PERF_CONTEXT_USER : PERF_CONTEXT_KERNEL; 37124248306SAdrian Hunter } 37200447ccdSAdrian Hunter 37324248306SAdrian Hunter void thread_stack__sample(struct thread *thread, struct ip_callchain *chain, 37424248306SAdrian Hunter size_t sz, u64 ip, u64 kernel_start) 37524248306SAdrian Hunter { 376bd8e68acSAdrian Hunter struct thread_stack *ts = thread__stack(thread); 37724248306SAdrian Hunter u64 context = callchain_context(ip, kernel_start); 37824248306SAdrian Hunter u64 last_context; 37924248306SAdrian Hunter size_t i, j; 38000447ccdSAdrian Hunter 38124248306SAdrian Hunter if (sz < 2) { 38224248306SAdrian Hunter chain->nr = 0; 38324248306SAdrian Hunter return; 38424248306SAdrian Hunter } 38500447ccdSAdrian Hunter 38624248306SAdrian Hunter chain->ips[0] = context; 38724248306SAdrian Hunter chain->ips[1] = ip; 38824248306SAdrian Hunter 389bd8e68acSAdrian Hunter if (!ts) { 39024248306SAdrian Hunter chain->nr = 2; 39124248306SAdrian Hunter return; 39224248306SAdrian Hunter } 39324248306SAdrian Hunter 39424248306SAdrian Hunter last_context = context; 39524248306SAdrian Hunter 396bd8e68acSAdrian Hunter for (i = 2, j = 1; i < sz && j <= ts->cnt; i++, j++) { 397bd8e68acSAdrian Hunter ip = ts->stack[ts->cnt - j].ret_addr; 39824248306SAdrian Hunter context = callchain_context(ip, kernel_start); 39924248306SAdrian Hunter if (context != last_context) { 40024248306SAdrian Hunter if (i >= sz - 1) 40124248306SAdrian Hunter break; 40224248306SAdrian Hunter chain->ips[i++] = context; 40324248306SAdrian Hunter last_context = context; 40424248306SAdrian Hunter } 40524248306SAdrian Hunter chain->ips[i] = ip; 40624248306SAdrian Hunter } 40724248306SAdrian Hunter 40824248306SAdrian Hunter chain->nr = i; 40900447ccdSAdrian Hunter } 41092a9e4f7SAdrian Hunter 41192a9e4f7SAdrian Hunter struct call_return_processor * 41292a9e4f7SAdrian Hunter call_return_processor__new(int (*process)(struct call_return *cr, void *data), 41392a9e4f7SAdrian Hunter void *data) 41492a9e4f7SAdrian Hunter { 41592a9e4f7SAdrian Hunter struct call_return_processor *crp; 41692a9e4f7SAdrian Hunter 41792a9e4f7SAdrian Hunter crp = zalloc(sizeof(struct call_return_processor)); 41892a9e4f7SAdrian Hunter if (!crp) 41992a9e4f7SAdrian Hunter return NULL; 42092a9e4f7SAdrian Hunter crp->cpr = call_path_root__new(); 42192a9e4f7SAdrian Hunter if (!crp->cpr) 42292a9e4f7SAdrian Hunter goto out_free; 42392a9e4f7SAdrian Hunter crp->process = process; 42492a9e4f7SAdrian Hunter crp->data = data; 42592a9e4f7SAdrian Hunter return crp; 42692a9e4f7SAdrian Hunter 42792a9e4f7SAdrian Hunter out_free: 42892a9e4f7SAdrian Hunter free(crp); 42992a9e4f7SAdrian Hunter return NULL; 43092a9e4f7SAdrian Hunter } 43192a9e4f7SAdrian Hunter 43292a9e4f7SAdrian Hunter void call_return_processor__free(struct call_return_processor *crp) 43392a9e4f7SAdrian Hunter { 43492a9e4f7SAdrian Hunter if (crp) { 43592a9e4f7SAdrian Hunter call_path_root__free(crp->cpr); 43692a9e4f7SAdrian Hunter free(crp); 43792a9e4f7SAdrian Hunter } 43892a9e4f7SAdrian Hunter } 43992a9e4f7SAdrian Hunter 44092a9e4f7SAdrian Hunter static int thread_stack__push_cp(struct thread_stack *ts, u64 ret_addr, 44192a9e4f7SAdrian Hunter u64 timestamp, u64 ref, struct call_path *cp, 4422dcde4e1SAdrian Hunter bool no_call, bool trace_end) 44392a9e4f7SAdrian Hunter { 44492a9e4f7SAdrian Hunter struct thread_stack_entry *tse; 44592a9e4f7SAdrian Hunter int err; 44692a9e4f7SAdrian Hunter 44792a9e4f7SAdrian Hunter if (ts->cnt == ts->sz) { 44892a9e4f7SAdrian Hunter err = thread_stack__grow(ts); 44992a9e4f7SAdrian Hunter if (err) 45092a9e4f7SAdrian Hunter return err; 45192a9e4f7SAdrian Hunter } 45292a9e4f7SAdrian Hunter 45392a9e4f7SAdrian Hunter tse = &ts->stack[ts->cnt++]; 45492a9e4f7SAdrian Hunter tse->ret_addr = ret_addr; 45592a9e4f7SAdrian Hunter tse->timestamp = timestamp; 45692a9e4f7SAdrian Hunter tse->ref = ref; 45792a9e4f7SAdrian Hunter tse->branch_count = ts->branch_count; 45892a9e4f7SAdrian Hunter tse->cp = cp; 45992a9e4f7SAdrian Hunter tse->no_call = no_call; 4602dcde4e1SAdrian Hunter tse->trace_end = trace_end; 46192a9e4f7SAdrian Hunter 46292a9e4f7SAdrian Hunter return 0; 46392a9e4f7SAdrian Hunter } 46492a9e4f7SAdrian Hunter 46592a9e4f7SAdrian Hunter static int thread_stack__pop_cp(struct thread *thread, struct thread_stack *ts, 46692a9e4f7SAdrian Hunter u64 ret_addr, u64 timestamp, u64 ref, 46792a9e4f7SAdrian Hunter struct symbol *sym) 46892a9e4f7SAdrian Hunter { 46992a9e4f7SAdrian Hunter int err; 47092a9e4f7SAdrian Hunter 47192a9e4f7SAdrian Hunter if (!ts->cnt) 47292a9e4f7SAdrian Hunter return 1; 47392a9e4f7SAdrian Hunter 47492a9e4f7SAdrian Hunter if (ts->cnt == 1) { 47592a9e4f7SAdrian Hunter struct thread_stack_entry *tse = &ts->stack[0]; 47692a9e4f7SAdrian Hunter 47792a9e4f7SAdrian Hunter if (tse->cp->sym == sym) 47892a9e4f7SAdrian Hunter return thread_stack__call_return(thread, ts, --ts->cnt, 47992a9e4f7SAdrian Hunter timestamp, ref, false); 48092a9e4f7SAdrian Hunter } 48192a9e4f7SAdrian Hunter 48292a9e4f7SAdrian Hunter if (ts->stack[ts->cnt - 1].ret_addr == ret_addr) { 48392a9e4f7SAdrian Hunter return thread_stack__call_return(thread, ts, --ts->cnt, 48492a9e4f7SAdrian Hunter timestamp, ref, false); 48592a9e4f7SAdrian Hunter } else { 48692a9e4f7SAdrian Hunter size_t i = ts->cnt - 1; 48792a9e4f7SAdrian Hunter 48892a9e4f7SAdrian Hunter while (i--) { 48992a9e4f7SAdrian Hunter if (ts->stack[i].ret_addr != ret_addr) 49092a9e4f7SAdrian Hunter continue; 49192a9e4f7SAdrian Hunter i += 1; 49292a9e4f7SAdrian Hunter while (ts->cnt > i) { 49392a9e4f7SAdrian Hunter err = thread_stack__call_return(thread, ts, 49492a9e4f7SAdrian Hunter --ts->cnt, 49592a9e4f7SAdrian Hunter timestamp, ref, 49692a9e4f7SAdrian Hunter true); 49792a9e4f7SAdrian Hunter if (err) 49892a9e4f7SAdrian Hunter return err; 49992a9e4f7SAdrian Hunter } 50092a9e4f7SAdrian Hunter return thread_stack__call_return(thread, ts, --ts->cnt, 50192a9e4f7SAdrian Hunter timestamp, ref, false); 50292a9e4f7SAdrian Hunter } 50392a9e4f7SAdrian Hunter } 50492a9e4f7SAdrian Hunter 50592a9e4f7SAdrian Hunter return 1; 50692a9e4f7SAdrian Hunter } 50792a9e4f7SAdrian Hunter 508e0b89511SAdrian Hunter static int thread_stack__bottom(struct thread_stack *ts, 50992a9e4f7SAdrian Hunter struct perf_sample *sample, 51092a9e4f7SAdrian Hunter struct addr_location *from_al, 51192a9e4f7SAdrian Hunter struct addr_location *to_al, u64 ref) 51292a9e4f7SAdrian Hunter { 51392a9e4f7SAdrian Hunter struct call_path_root *cpr = ts->crp->cpr; 51492a9e4f7SAdrian Hunter struct call_path *cp; 51592a9e4f7SAdrian Hunter struct symbol *sym; 51692a9e4f7SAdrian Hunter u64 ip; 51792a9e4f7SAdrian Hunter 51892a9e4f7SAdrian Hunter if (sample->ip) { 51992a9e4f7SAdrian Hunter ip = sample->ip; 52092a9e4f7SAdrian Hunter sym = from_al->sym; 52192a9e4f7SAdrian Hunter } else if (sample->addr) { 52292a9e4f7SAdrian Hunter ip = sample->addr; 52392a9e4f7SAdrian Hunter sym = to_al->sym; 52492a9e4f7SAdrian Hunter } else { 52592a9e4f7SAdrian Hunter return 0; 52692a9e4f7SAdrian Hunter } 52792a9e4f7SAdrian Hunter 52892a9e4f7SAdrian Hunter cp = call_path__findnew(cpr, &cpr->call_path, sym, ip, 52992a9e4f7SAdrian Hunter ts->kernel_start); 53092a9e4f7SAdrian Hunter if (!cp) 53192a9e4f7SAdrian Hunter return -ENOMEM; 53292a9e4f7SAdrian Hunter 533e0b89511SAdrian Hunter return thread_stack__push_cp(ts, ip, sample->time, ref, cp, 5342dcde4e1SAdrian Hunter true, false); 53592a9e4f7SAdrian Hunter } 53692a9e4f7SAdrian Hunter 53792a9e4f7SAdrian Hunter static int thread_stack__no_call_return(struct thread *thread, 53892a9e4f7SAdrian Hunter struct thread_stack *ts, 53992a9e4f7SAdrian Hunter struct perf_sample *sample, 54092a9e4f7SAdrian Hunter struct addr_location *from_al, 54192a9e4f7SAdrian Hunter struct addr_location *to_al, u64 ref) 54292a9e4f7SAdrian Hunter { 54392a9e4f7SAdrian Hunter struct call_path_root *cpr = ts->crp->cpr; 54492a9e4f7SAdrian Hunter struct call_path *cp, *parent; 54592a9e4f7SAdrian Hunter u64 ks = ts->kernel_start; 54692a9e4f7SAdrian Hunter int err; 54792a9e4f7SAdrian Hunter 54892a9e4f7SAdrian Hunter if (sample->ip >= ks && sample->addr < ks) { 54992a9e4f7SAdrian Hunter /* Return to userspace, so pop all kernel addresses */ 55092a9e4f7SAdrian Hunter while (thread_stack__in_kernel(ts)) { 55192a9e4f7SAdrian Hunter err = thread_stack__call_return(thread, ts, --ts->cnt, 55292a9e4f7SAdrian Hunter sample->time, ref, 55392a9e4f7SAdrian Hunter true); 55492a9e4f7SAdrian Hunter if (err) 55592a9e4f7SAdrian Hunter return err; 55692a9e4f7SAdrian Hunter } 55792a9e4f7SAdrian Hunter 55892a9e4f7SAdrian Hunter /* If the stack is empty, push the userspace address */ 55992a9e4f7SAdrian Hunter if (!ts->cnt) { 56092a9e4f7SAdrian Hunter cp = call_path__findnew(cpr, &cpr->call_path, 56192a9e4f7SAdrian Hunter to_al->sym, sample->addr, 56292a9e4f7SAdrian Hunter ts->kernel_start); 56392a9e4f7SAdrian Hunter if (!cp) 56492a9e4f7SAdrian Hunter return -ENOMEM; 56592a9e4f7SAdrian Hunter return thread_stack__push_cp(ts, 0, sample->time, ref, 5662dcde4e1SAdrian Hunter cp, true, false); 56792a9e4f7SAdrian Hunter } 56892a9e4f7SAdrian Hunter } else if (thread_stack__in_kernel(ts) && sample->ip < ks) { 56992a9e4f7SAdrian Hunter /* Return to userspace, so pop all kernel addresses */ 57092a9e4f7SAdrian Hunter while (thread_stack__in_kernel(ts)) { 57192a9e4f7SAdrian Hunter err = thread_stack__call_return(thread, ts, --ts->cnt, 57292a9e4f7SAdrian Hunter sample->time, ref, 57392a9e4f7SAdrian Hunter true); 57492a9e4f7SAdrian Hunter if (err) 57592a9e4f7SAdrian Hunter return err; 57692a9e4f7SAdrian Hunter } 57792a9e4f7SAdrian Hunter } 57892a9e4f7SAdrian Hunter 57992a9e4f7SAdrian Hunter if (ts->cnt) 58092a9e4f7SAdrian Hunter parent = ts->stack[ts->cnt - 1].cp; 58192a9e4f7SAdrian Hunter else 58292a9e4f7SAdrian Hunter parent = &cpr->call_path; 58392a9e4f7SAdrian Hunter 58492a9e4f7SAdrian Hunter /* This 'return' had no 'call', so push and pop top of stack */ 58592a9e4f7SAdrian Hunter cp = call_path__findnew(cpr, parent, from_al->sym, sample->ip, 58692a9e4f7SAdrian Hunter ts->kernel_start); 58792a9e4f7SAdrian Hunter if (!cp) 58892a9e4f7SAdrian Hunter return -ENOMEM; 58992a9e4f7SAdrian Hunter 59092a9e4f7SAdrian Hunter err = thread_stack__push_cp(ts, sample->addr, sample->time, ref, cp, 5912dcde4e1SAdrian Hunter true, false); 59292a9e4f7SAdrian Hunter if (err) 59392a9e4f7SAdrian Hunter return err; 59492a9e4f7SAdrian Hunter 59592a9e4f7SAdrian Hunter return thread_stack__pop_cp(thread, ts, sample->addr, sample->time, ref, 59692a9e4f7SAdrian Hunter to_al->sym); 59792a9e4f7SAdrian Hunter } 59892a9e4f7SAdrian Hunter 59992a9e4f7SAdrian Hunter static int thread_stack__trace_begin(struct thread *thread, 60092a9e4f7SAdrian Hunter struct thread_stack *ts, u64 timestamp, 60192a9e4f7SAdrian Hunter u64 ref) 60292a9e4f7SAdrian Hunter { 60392a9e4f7SAdrian Hunter struct thread_stack_entry *tse; 60492a9e4f7SAdrian Hunter int err; 60592a9e4f7SAdrian Hunter 60692a9e4f7SAdrian Hunter if (!ts->cnt) 60792a9e4f7SAdrian Hunter return 0; 60892a9e4f7SAdrian Hunter 60992a9e4f7SAdrian Hunter /* Pop trace end */ 61092a9e4f7SAdrian Hunter tse = &ts->stack[ts->cnt - 1]; 6112dcde4e1SAdrian Hunter if (tse->trace_end) { 61292a9e4f7SAdrian Hunter err = thread_stack__call_return(thread, ts, --ts->cnt, 61392a9e4f7SAdrian Hunter timestamp, ref, false); 61492a9e4f7SAdrian Hunter if (err) 61592a9e4f7SAdrian Hunter return err; 61692a9e4f7SAdrian Hunter } 61792a9e4f7SAdrian Hunter 61892a9e4f7SAdrian Hunter return 0; 61992a9e4f7SAdrian Hunter } 62092a9e4f7SAdrian Hunter 62192a9e4f7SAdrian Hunter static int thread_stack__trace_end(struct thread_stack *ts, 62292a9e4f7SAdrian Hunter struct perf_sample *sample, u64 ref) 62392a9e4f7SAdrian Hunter { 62492a9e4f7SAdrian Hunter struct call_path_root *cpr = ts->crp->cpr; 62592a9e4f7SAdrian Hunter struct call_path *cp; 62692a9e4f7SAdrian Hunter u64 ret_addr; 62792a9e4f7SAdrian Hunter 62892a9e4f7SAdrian Hunter /* No point having 'trace end' on the bottom of the stack */ 62992a9e4f7SAdrian Hunter if (!ts->cnt || (ts->cnt == 1 && ts->stack[0].ref == ref)) 63092a9e4f7SAdrian Hunter return 0; 63192a9e4f7SAdrian Hunter 63292a9e4f7SAdrian Hunter cp = call_path__findnew(cpr, ts->stack[ts->cnt - 1].cp, NULL, 0, 63392a9e4f7SAdrian Hunter ts->kernel_start); 63492a9e4f7SAdrian Hunter if (!cp) 63592a9e4f7SAdrian Hunter return -ENOMEM; 63692a9e4f7SAdrian Hunter 63792a9e4f7SAdrian Hunter ret_addr = sample->ip + sample->insn_len; 63892a9e4f7SAdrian Hunter 63992a9e4f7SAdrian Hunter return thread_stack__push_cp(ts, ret_addr, sample->time, ref, cp, 6402dcde4e1SAdrian Hunter false, true); 64192a9e4f7SAdrian Hunter } 64292a9e4f7SAdrian Hunter 64392a9e4f7SAdrian Hunter int thread_stack__process(struct thread *thread, struct comm *comm, 64492a9e4f7SAdrian Hunter struct perf_sample *sample, 64592a9e4f7SAdrian Hunter struct addr_location *from_al, 64692a9e4f7SAdrian Hunter struct addr_location *to_al, u64 ref, 64792a9e4f7SAdrian Hunter struct call_return_processor *crp) 64892a9e4f7SAdrian Hunter { 649bd8e68acSAdrian Hunter struct thread_stack *ts = thread__stack(thread); 65092a9e4f7SAdrian Hunter int err = 0; 65192a9e4f7SAdrian Hunter 65203b32cb2SAdrian Hunter if (ts && !ts->crp) { 65392a9e4f7SAdrian Hunter /* Supersede thread_stack__event() */ 654f6060ac6SAdrian Hunter thread_stack__reset(thread, ts); 65503b32cb2SAdrian Hunter ts = NULL; 65692a9e4f7SAdrian Hunter } 65703b32cb2SAdrian Hunter 65803b32cb2SAdrian Hunter if (!ts) { 659bd8e68acSAdrian Hunter ts = thread_stack__new(thread, crp); 660bd8e68acSAdrian Hunter if (!ts) 66192a9e4f7SAdrian Hunter return -ENOMEM; 66292a9e4f7SAdrian Hunter ts->comm = comm; 66392a9e4f7SAdrian Hunter } 66492a9e4f7SAdrian Hunter 66592a9e4f7SAdrian Hunter /* Flush stack on exec */ 66692a9e4f7SAdrian Hunter if (ts->comm != comm && thread->pid_ == thread->tid) { 667a5499b37SAdrian Hunter err = __thread_stack__flush(thread, ts); 66892a9e4f7SAdrian Hunter if (err) 66992a9e4f7SAdrian Hunter return err; 67092a9e4f7SAdrian Hunter ts->comm = comm; 67192a9e4f7SAdrian Hunter } 67292a9e4f7SAdrian Hunter 67392a9e4f7SAdrian Hunter /* If the stack is empty, put the current symbol on the stack */ 67492a9e4f7SAdrian Hunter if (!ts->cnt) { 675e0b89511SAdrian Hunter err = thread_stack__bottom(ts, sample, from_al, to_al, ref); 67692a9e4f7SAdrian Hunter if (err) 67792a9e4f7SAdrian Hunter return err; 67892a9e4f7SAdrian Hunter } 67992a9e4f7SAdrian Hunter 68092a9e4f7SAdrian Hunter ts->branch_count += 1; 68192a9e4f7SAdrian Hunter ts->last_time = sample->time; 68292a9e4f7SAdrian Hunter 68392a9e4f7SAdrian Hunter if (sample->flags & PERF_IP_FLAG_CALL) { 6842dcde4e1SAdrian Hunter bool trace_end = sample->flags & PERF_IP_FLAG_TRACE_END; 68592a9e4f7SAdrian Hunter struct call_path_root *cpr = ts->crp->cpr; 68692a9e4f7SAdrian Hunter struct call_path *cp; 68792a9e4f7SAdrian Hunter u64 ret_addr; 68892a9e4f7SAdrian Hunter 68992a9e4f7SAdrian Hunter if (!sample->ip || !sample->addr) 69092a9e4f7SAdrian Hunter return 0; 69192a9e4f7SAdrian Hunter 69292a9e4f7SAdrian Hunter ret_addr = sample->ip + sample->insn_len; 69392a9e4f7SAdrian Hunter if (ret_addr == sample->addr) 69492a9e4f7SAdrian Hunter return 0; /* Zero-length calls are excluded */ 69592a9e4f7SAdrian Hunter 69692a9e4f7SAdrian Hunter cp = call_path__findnew(cpr, ts->stack[ts->cnt - 1].cp, 69792a9e4f7SAdrian Hunter to_al->sym, sample->addr, 69892a9e4f7SAdrian Hunter ts->kernel_start); 69992a9e4f7SAdrian Hunter if (!cp) 70092a9e4f7SAdrian Hunter return -ENOMEM; 70192a9e4f7SAdrian Hunter err = thread_stack__push_cp(ts, ret_addr, sample->time, ref, 7022dcde4e1SAdrian Hunter cp, false, trace_end); 70392a9e4f7SAdrian Hunter } else if (sample->flags & PERF_IP_FLAG_RETURN) { 70492a9e4f7SAdrian Hunter if (!sample->ip || !sample->addr) 70592a9e4f7SAdrian Hunter return 0; 70692a9e4f7SAdrian Hunter 70792a9e4f7SAdrian Hunter err = thread_stack__pop_cp(thread, ts, sample->addr, 70892a9e4f7SAdrian Hunter sample->time, ref, from_al->sym); 70992a9e4f7SAdrian Hunter if (err) { 71092a9e4f7SAdrian Hunter if (err < 0) 71192a9e4f7SAdrian Hunter return err; 71292a9e4f7SAdrian Hunter err = thread_stack__no_call_return(thread, ts, sample, 71392a9e4f7SAdrian Hunter from_al, to_al, ref); 71492a9e4f7SAdrian Hunter } 71592a9e4f7SAdrian Hunter } else if (sample->flags & PERF_IP_FLAG_TRACE_BEGIN) { 71692a9e4f7SAdrian Hunter err = thread_stack__trace_begin(thread, ts, sample->time, ref); 71792a9e4f7SAdrian Hunter } else if (sample->flags & PERF_IP_FLAG_TRACE_END) { 71892a9e4f7SAdrian Hunter err = thread_stack__trace_end(ts, sample, ref); 71992a9e4f7SAdrian Hunter } 72092a9e4f7SAdrian Hunter 72192a9e4f7SAdrian Hunter return err; 72292a9e4f7SAdrian Hunter } 723e216708dSAdrian Hunter 724e216708dSAdrian Hunter size_t thread_stack__depth(struct thread *thread) 725e216708dSAdrian Hunter { 726bd8e68acSAdrian Hunter struct thread_stack *ts = thread__stack(thread); 727bd8e68acSAdrian Hunter 728bd8e68acSAdrian Hunter if (!ts) 729e216708dSAdrian Hunter return 0; 730bd8e68acSAdrian Hunter return ts->cnt; 731e216708dSAdrian Hunter } 732