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 6392a9e4f7SAdrian Hunter */ 6400447ccdSAdrian Hunter struct thread_stack { 6500447ccdSAdrian Hunter struct thread_stack_entry *stack; 6600447ccdSAdrian Hunter size_t cnt; 6700447ccdSAdrian Hunter size_t sz; 6800447ccdSAdrian Hunter u64 trace_nr; 6992a9e4f7SAdrian Hunter u64 branch_count; 7092a9e4f7SAdrian Hunter u64 kernel_start; 7192a9e4f7SAdrian Hunter u64 last_time; 7292a9e4f7SAdrian Hunter struct call_return_processor *crp; 7392a9e4f7SAdrian Hunter struct comm *comm; 7400447ccdSAdrian Hunter }; 7500447ccdSAdrian Hunter 7600447ccdSAdrian Hunter static int thread_stack__grow(struct thread_stack *ts) 7700447ccdSAdrian Hunter { 7800447ccdSAdrian Hunter struct thread_stack_entry *new_stack; 7900447ccdSAdrian Hunter size_t sz, new_sz; 8000447ccdSAdrian Hunter 8100447ccdSAdrian Hunter new_sz = ts->sz + STACK_GROWTH; 8200447ccdSAdrian Hunter sz = new_sz * sizeof(struct thread_stack_entry); 8300447ccdSAdrian Hunter 8400447ccdSAdrian Hunter new_stack = realloc(ts->stack, sz); 8500447ccdSAdrian Hunter if (!new_stack) 8600447ccdSAdrian Hunter return -ENOMEM; 8700447ccdSAdrian Hunter 8800447ccdSAdrian Hunter ts->stack = new_stack; 8900447ccdSAdrian Hunter ts->sz = new_sz; 9000447ccdSAdrian Hunter 9100447ccdSAdrian Hunter return 0; 9200447ccdSAdrian Hunter } 9300447ccdSAdrian Hunter 9492a9e4f7SAdrian Hunter static struct thread_stack *thread_stack__new(struct thread *thread, 9592a9e4f7SAdrian Hunter struct call_return_processor *crp) 9600447ccdSAdrian Hunter { 9700447ccdSAdrian Hunter struct thread_stack *ts; 9800447ccdSAdrian Hunter 9900447ccdSAdrian Hunter ts = zalloc(sizeof(struct thread_stack)); 10000447ccdSAdrian Hunter if (!ts) 10100447ccdSAdrian Hunter return NULL; 10200447ccdSAdrian Hunter 10300447ccdSAdrian Hunter if (thread_stack__grow(ts)) { 10400447ccdSAdrian Hunter free(ts); 10500447ccdSAdrian Hunter return NULL; 10600447ccdSAdrian Hunter } 10700447ccdSAdrian Hunter 10892a9e4f7SAdrian Hunter if (thread->mg && thread->mg->machine) 10992a9e4f7SAdrian Hunter ts->kernel_start = machine__kernel_start(thread->mg->machine); 11092a9e4f7SAdrian Hunter else 11192a9e4f7SAdrian Hunter ts->kernel_start = 1ULL << 63; 11292a9e4f7SAdrian Hunter ts->crp = crp; 11392a9e4f7SAdrian Hunter 11400447ccdSAdrian Hunter return ts; 11500447ccdSAdrian Hunter } 11600447ccdSAdrian Hunter 1174d60e5e3SAdrian Hunter static int thread_stack__push(struct thread_stack *ts, u64 ret_addr, 1184d60e5e3SAdrian Hunter bool trace_end) 11900447ccdSAdrian Hunter { 12000447ccdSAdrian Hunter int err = 0; 12100447ccdSAdrian Hunter 12200447ccdSAdrian Hunter if (ts->cnt == ts->sz) { 12300447ccdSAdrian Hunter err = thread_stack__grow(ts); 12400447ccdSAdrian Hunter if (err) { 12500447ccdSAdrian Hunter pr_warning("Out of memory: discarding thread stack\n"); 12600447ccdSAdrian Hunter ts->cnt = 0; 12700447ccdSAdrian Hunter } 12800447ccdSAdrian Hunter } 12900447ccdSAdrian Hunter 1304d60e5e3SAdrian Hunter ts->stack[ts->cnt].trace_end = trace_end; 13100447ccdSAdrian Hunter ts->stack[ts->cnt++].ret_addr = ret_addr; 13200447ccdSAdrian Hunter 13300447ccdSAdrian Hunter return err; 13400447ccdSAdrian Hunter } 13500447ccdSAdrian Hunter 13600447ccdSAdrian Hunter static void thread_stack__pop(struct thread_stack *ts, u64 ret_addr) 13700447ccdSAdrian Hunter { 13800447ccdSAdrian Hunter size_t i; 13900447ccdSAdrian Hunter 14000447ccdSAdrian Hunter /* 14100447ccdSAdrian Hunter * In some cases there may be functions which are not seen to return. 14200447ccdSAdrian Hunter * For example when setjmp / longjmp has been used. Or the perf context 14300447ccdSAdrian Hunter * switch in the kernel which doesn't stop and start tracing in exactly 14400447ccdSAdrian Hunter * the same code path. When that happens the return address will be 14500447ccdSAdrian Hunter * further down the stack. If the return address is not found at all, 14600447ccdSAdrian Hunter * we assume the opposite (i.e. this is a return for a call that wasn't 14700447ccdSAdrian Hunter * seen for some reason) and leave the stack alone. 14800447ccdSAdrian Hunter */ 14900447ccdSAdrian Hunter for (i = ts->cnt; i; ) { 15000447ccdSAdrian Hunter if (ts->stack[--i].ret_addr == ret_addr) { 15100447ccdSAdrian Hunter ts->cnt = i; 15200447ccdSAdrian Hunter return; 15300447ccdSAdrian Hunter } 15400447ccdSAdrian Hunter } 15500447ccdSAdrian Hunter } 15600447ccdSAdrian Hunter 1574d60e5e3SAdrian Hunter static void thread_stack__pop_trace_end(struct thread_stack *ts) 1584d60e5e3SAdrian Hunter { 1594d60e5e3SAdrian Hunter size_t i; 1604d60e5e3SAdrian Hunter 1614d60e5e3SAdrian Hunter for (i = ts->cnt; i; ) { 1624d60e5e3SAdrian Hunter if (ts->stack[--i].trace_end) 1634d60e5e3SAdrian Hunter ts->cnt = i; 1644d60e5e3SAdrian Hunter else 1654d60e5e3SAdrian Hunter return; 1664d60e5e3SAdrian Hunter } 1674d60e5e3SAdrian Hunter } 1684d60e5e3SAdrian Hunter 16992a9e4f7SAdrian Hunter static bool thread_stack__in_kernel(struct thread_stack *ts) 17092a9e4f7SAdrian Hunter { 17192a9e4f7SAdrian Hunter if (!ts->cnt) 17292a9e4f7SAdrian Hunter return false; 17392a9e4f7SAdrian Hunter 17492a9e4f7SAdrian Hunter return ts->stack[ts->cnt - 1].cp->in_kernel; 17592a9e4f7SAdrian Hunter } 17692a9e4f7SAdrian Hunter 17792a9e4f7SAdrian Hunter static int thread_stack__call_return(struct thread *thread, 17892a9e4f7SAdrian Hunter struct thread_stack *ts, size_t idx, 17992a9e4f7SAdrian Hunter u64 timestamp, u64 ref, bool no_return) 18092a9e4f7SAdrian Hunter { 18192a9e4f7SAdrian Hunter struct call_return_processor *crp = ts->crp; 18292a9e4f7SAdrian Hunter struct thread_stack_entry *tse; 18392a9e4f7SAdrian Hunter struct call_return cr = { 18492a9e4f7SAdrian Hunter .thread = thread, 18592a9e4f7SAdrian Hunter .comm = ts->comm, 18692a9e4f7SAdrian Hunter .db_id = 0, 18792a9e4f7SAdrian Hunter }; 18892a9e4f7SAdrian Hunter 18992a9e4f7SAdrian Hunter tse = &ts->stack[idx]; 19092a9e4f7SAdrian Hunter cr.cp = tse->cp; 19192a9e4f7SAdrian Hunter cr.call_time = tse->timestamp; 19292a9e4f7SAdrian Hunter cr.return_time = timestamp; 19392a9e4f7SAdrian Hunter cr.branch_count = ts->branch_count - tse->branch_count; 19492a9e4f7SAdrian Hunter cr.call_ref = tse->ref; 19592a9e4f7SAdrian Hunter cr.return_ref = ref; 19692a9e4f7SAdrian Hunter if (tse->no_call) 19792a9e4f7SAdrian Hunter cr.flags |= CALL_RETURN_NO_CALL; 19892a9e4f7SAdrian Hunter if (no_return) 19992a9e4f7SAdrian Hunter cr.flags |= CALL_RETURN_NO_RETURN; 20092a9e4f7SAdrian Hunter 20192a9e4f7SAdrian Hunter return crp->process(&cr, crp->data); 20292a9e4f7SAdrian Hunter } 20392a9e4f7SAdrian Hunter 204a5499b37SAdrian Hunter static int __thread_stack__flush(struct thread *thread, struct thread_stack *ts) 20592a9e4f7SAdrian Hunter { 20692a9e4f7SAdrian Hunter struct call_return_processor *crp = ts->crp; 20792a9e4f7SAdrian Hunter int err; 20892a9e4f7SAdrian Hunter 20992a9e4f7SAdrian Hunter if (!crp) { 21092a9e4f7SAdrian Hunter ts->cnt = 0; 21192a9e4f7SAdrian Hunter return 0; 21292a9e4f7SAdrian Hunter } 21392a9e4f7SAdrian Hunter 21492a9e4f7SAdrian Hunter while (ts->cnt) { 21592a9e4f7SAdrian Hunter err = thread_stack__call_return(thread, ts, --ts->cnt, 21692a9e4f7SAdrian Hunter ts->last_time, 0, true); 21792a9e4f7SAdrian Hunter if (err) { 21892a9e4f7SAdrian Hunter pr_err("Error flushing thread stack!\n"); 21992a9e4f7SAdrian Hunter ts->cnt = 0; 22092a9e4f7SAdrian Hunter return err; 22192a9e4f7SAdrian Hunter } 22292a9e4f7SAdrian Hunter } 22392a9e4f7SAdrian Hunter 22492a9e4f7SAdrian Hunter return 0; 22592a9e4f7SAdrian Hunter } 22692a9e4f7SAdrian Hunter 227a5499b37SAdrian Hunter int thread_stack__flush(struct thread *thread) 228a5499b37SAdrian Hunter { 229a5499b37SAdrian Hunter if (thread->ts) 230a5499b37SAdrian Hunter return __thread_stack__flush(thread, thread->ts); 231a5499b37SAdrian Hunter 232a5499b37SAdrian Hunter return 0; 233a5499b37SAdrian Hunter } 234a5499b37SAdrian Hunter 23500447ccdSAdrian Hunter int thread_stack__event(struct thread *thread, u32 flags, u64 from_ip, 23600447ccdSAdrian Hunter u64 to_ip, u16 insn_len, u64 trace_nr) 23700447ccdSAdrian Hunter { 23800447ccdSAdrian Hunter if (!thread) 23900447ccdSAdrian Hunter return -EINVAL; 24000447ccdSAdrian Hunter 24100447ccdSAdrian Hunter if (!thread->ts) { 24292a9e4f7SAdrian Hunter thread->ts = thread_stack__new(thread, NULL); 24300447ccdSAdrian Hunter if (!thread->ts) { 24400447ccdSAdrian Hunter pr_warning("Out of memory: no thread stack\n"); 24500447ccdSAdrian Hunter return -ENOMEM; 24600447ccdSAdrian Hunter } 24700447ccdSAdrian Hunter thread->ts->trace_nr = trace_nr; 24800447ccdSAdrian Hunter } 24900447ccdSAdrian Hunter 25000447ccdSAdrian Hunter /* 25100447ccdSAdrian Hunter * When the trace is discontinuous, the trace_nr changes. In that case 25200447ccdSAdrian Hunter * the stack might be completely invalid. Better to report nothing than 25392a9e4f7SAdrian Hunter * to report something misleading, so flush the stack. 25400447ccdSAdrian Hunter */ 25500447ccdSAdrian Hunter if (trace_nr != thread->ts->trace_nr) { 25692a9e4f7SAdrian Hunter if (thread->ts->trace_nr) 257a5499b37SAdrian Hunter __thread_stack__flush(thread, thread->ts); 25800447ccdSAdrian Hunter thread->ts->trace_nr = trace_nr; 25900447ccdSAdrian Hunter } 26000447ccdSAdrian Hunter 26192a9e4f7SAdrian Hunter /* Stop here if thread_stack__process() is in use */ 26292a9e4f7SAdrian Hunter if (thread->ts->crp) 26392a9e4f7SAdrian Hunter return 0; 26492a9e4f7SAdrian Hunter 26500447ccdSAdrian Hunter if (flags & PERF_IP_FLAG_CALL) { 26600447ccdSAdrian Hunter u64 ret_addr; 26700447ccdSAdrian Hunter 26800447ccdSAdrian Hunter if (!to_ip) 26900447ccdSAdrian Hunter return 0; 27000447ccdSAdrian Hunter ret_addr = from_ip + insn_len; 27100447ccdSAdrian Hunter if (ret_addr == to_ip) 27200447ccdSAdrian Hunter return 0; /* Zero-length calls are excluded */ 2734d60e5e3SAdrian Hunter return thread_stack__push(thread->ts, ret_addr, 2744d60e5e3SAdrian Hunter flags & PERF_IP_FLAG_TRACE_END); 2754d60e5e3SAdrian Hunter } else if (flags & PERF_IP_FLAG_TRACE_BEGIN) { 2764d60e5e3SAdrian Hunter /* 2774d60e5e3SAdrian Hunter * If the caller did not change the trace number (which would 2784d60e5e3SAdrian Hunter * have flushed the stack) then try to make sense of the stack. 2794d60e5e3SAdrian Hunter * Possibly, tracing began after returning to the current 2804d60e5e3SAdrian Hunter * address, so try to pop that. Also, do not expect a call made 2814d60e5e3SAdrian Hunter * when the trace ended, to return, so pop that. 2824d60e5e3SAdrian Hunter */ 2834d60e5e3SAdrian Hunter thread_stack__pop(thread->ts, to_ip); 2844d60e5e3SAdrian Hunter thread_stack__pop_trace_end(thread->ts); 2854d60e5e3SAdrian Hunter } else if ((flags & PERF_IP_FLAG_RETURN) && from_ip) { 28600447ccdSAdrian Hunter thread_stack__pop(thread->ts, to_ip); 28700447ccdSAdrian Hunter } 28800447ccdSAdrian Hunter 28900447ccdSAdrian Hunter return 0; 29000447ccdSAdrian Hunter } 29100447ccdSAdrian Hunter 29292a9e4f7SAdrian Hunter void thread_stack__set_trace_nr(struct thread *thread, u64 trace_nr) 29392a9e4f7SAdrian Hunter { 29492a9e4f7SAdrian Hunter if (!thread || !thread->ts) 29592a9e4f7SAdrian Hunter return; 29692a9e4f7SAdrian Hunter 29792a9e4f7SAdrian Hunter if (trace_nr != thread->ts->trace_nr) { 29892a9e4f7SAdrian Hunter if (thread->ts->trace_nr) 299a5499b37SAdrian Hunter __thread_stack__flush(thread, thread->ts); 30092a9e4f7SAdrian Hunter thread->ts->trace_nr = trace_nr; 30192a9e4f7SAdrian Hunter } 30292a9e4f7SAdrian Hunter } 30392a9e4f7SAdrian Hunter 30400447ccdSAdrian Hunter void thread_stack__free(struct thread *thread) 30500447ccdSAdrian Hunter { 30600447ccdSAdrian Hunter if (thread->ts) { 307a5499b37SAdrian Hunter __thread_stack__flush(thread, thread->ts); 30800447ccdSAdrian Hunter zfree(&thread->ts->stack); 30900447ccdSAdrian Hunter zfree(&thread->ts); 31000447ccdSAdrian Hunter } 31100447ccdSAdrian Hunter } 31200447ccdSAdrian Hunter 31324248306SAdrian Hunter static inline u64 callchain_context(u64 ip, u64 kernel_start) 31400447ccdSAdrian Hunter { 31524248306SAdrian Hunter return ip < kernel_start ? PERF_CONTEXT_USER : PERF_CONTEXT_KERNEL; 31624248306SAdrian Hunter } 31700447ccdSAdrian Hunter 31824248306SAdrian Hunter void thread_stack__sample(struct thread *thread, struct ip_callchain *chain, 31924248306SAdrian Hunter size_t sz, u64 ip, u64 kernel_start) 32024248306SAdrian Hunter { 32124248306SAdrian Hunter u64 context = callchain_context(ip, kernel_start); 32224248306SAdrian Hunter u64 last_context; 32324248306SAdrian Hunter size_t i, j; 32400447ccdSAdrian Hunter 32524248306SAdrian Hunter if (sz < 2) { 32624248306SAdrian Hunter chain->nr = 0; 32724248306SAdrian Hunter return; 32824248306SAdrian Hunter } 32900447ccdSAdrian Hunter 33024248306SAdrian Hunter chain->ips[0] = context; 33124248306SAdrian Hunter chain->ips[1] = ip; 33224248306SAdrian Hunter 33324248306SAdrian Hunter if (!thread || !thread->ts) { 33424248306SAdrian Hunter chain->nr = 2; 33524248306SAdrian Hunter return; 33624248306SAdrian Hunter } 33724248306SAdrian Hunter 33824248306SAdrian Hunter last_context = context; 33924248306SAdrian Hunter 34024248306SAdrian Hunter for (i = 2, j = 1; i < sz && j <= thread->ts->cnt; i++, j++) { 34124248306SAdrian Hunter ip = thread->ts->stack[thread->ts->cnt - j].ret_addr; 34224248306SAdrian Hunter context = callchain_context(ip, kernel_start); 34324248306SAdrian Hunter if (context != last_context) { 34424248306SAdrian Hunter if (i >= sz - 1) 34524248306SAdrian Hunter break; 34624248306SAdrian Hunter chain->ips[i++] = context; 34724248306SAdrian Hunter last_context = context; 34824248306SAdrian Hunter } 34924248306SAdrian Hunter chain->ips[i] = ip; 35024248306SAdrian Hunter } 35124248306SAdrian Hunter 35224248306SAdrian Hunter chain->nr = i; 35300447ccdSAdrian Hunter } 35492a9e4f7SAdrian Hunter 35592a9e4f7SAdrian Hunter struct call_return_processor * 35692a9e4f7SAdrian Hunter call_return_processor__new(int (*process)(struct call_return *cr, void *data), 35792a9e4f7SAdrian Hunter void *data) 35892a9e4f7SAdrian Hunter { 35992a9e4f7SAdrian Hunter struct call_return_processor *crp; 36092a9e4f7SAdrian Hunter 36192a9e4f7SAdrian Hunter crp = zalloc(sizeof(struct call_return_processor)); 36292a9e4f7SAdrian Hunter if (!crp) 36392a9e4f7SAdrian Hunter return NULL; 36492a9e4f7SAdrian Hunter crp->cpr = call_path_root__new(); 36592a9e4f7SAdrian Hunter if (!crp->cpr) 36692a9e4f7SAdrian Hunter goto out_free; 36792a9e4f7SAdrian Hunter crp->process = process; 36892a9e4f7SAdrian Hunter crp->data = data; 36992a9e4f7SAdrian Hunter return crp; 37092a9e4f7SAdrian Hunter 37192a9e4f7SAdrian Hunter out_free: 37292a9e4f7SAdrian Hunter free(crp); 37392a9e4f7SAdrian Hunter return NULL; 37492a9e4f7SAdrian Hunter } 37592a9e4f7SAdrian Hunter 37692a9e4f7SAdrian Hunter void call_return_processor__free(struct call_return_processor *crp) 37792a9e4f7SAdrian Hunter { 37892a9e4f7SAdrian Hunter if (crp) { 37992a9e4f7SAdrian Hunter call_path_root__free(crp->cpr); 38092a9e4f7SAdrian Hunter free(crp); 38192a9e4f7SAdrian Hunter } 38292a9e4f7SAdrian Hunter } 38392a9e4f7SAdrian Hunter 38492a9e4f7SAdrian Hunter static int thread_stack__push_cp(struct thread_stack *ts, u64 ret_addr, 38592a9e4f7SAdrian Hunter u64 timestamp, u64 ref, struct call_path *cp, 3862dcde4e1SAdrian Hunter bool no_call, bool trace_end) 38792a9e4f7SAdrian Hunter { 38892a9e4f7SAdrian Hunter struct thread_stack_entry *tse; 38992a9e4f7SAdrian Hunter int err; 39092a9e4f7SAdrian Hunter 39192a9e4f7SAdrian Hunter if (ts->cnt == ts->sz) { 39292a9e4f7SAdrian Hunter err = thread_stack__grow(ts); 39392a9e4f7SAdrian Hunter if (err) 39492a9e4f7SAdrian Hunter return err; 39592a9e4f7SAdrian Hunter } 39692a9e4f7SAdrian Hunter 39792a9e4f7SAdrian Hunter tse = &ts->stack[ts->cnt++]; 39892a9e4f7SAdrian Hunter tse->ret_addr = ret_addr; 39992a9e4f7SAdrian Hunter tse->timestamp = timestamp; 40092a9e4f7SAdrian Hunter tse->ref = ref; 40192a9e4f7SAdrian Hunter tse->branch_count = ts->branch_count; 40292a9e4f7SAdrian Hunter tse->cp = cp; 40392a9e4f7SAdrian Hunter tse->no_call = no_call; 4042dcde4e1SAdrian Hunter tse->trace_end = trace_end; 40592a9e4f7SAdrian Hunter 40692a9e4f7SAdrian Hunter return 0; 40792a9e4f7SAdrian Hunter } 40892a9e4f7SAdrian Hunter 40992a9e4f7SAdrian Hunter static int thread_stack__pop_cp(struct thread *thread, struct thread_stack *ts, 41092a9e4f7SAdrian Hunter u64 ret_addr, u64 timestamp, u64 ref, 41192a9e4f7SAdrian Hunter struct symbol *sym) 41292a9e4f7SAdrian Hunter { 41392a9e4f7SAdrian Hunter int err; 41492a9e4f7SAdrian Hunter 41592a9e4f7SAdrian Hunter if (!ts->cnt) 41692a9e4f7SAdrian Hunter return 1; 41792a9e4f7SAdrian Hunter 41892a9e4f7SAdrian Hunter if (ts->cnt == 1) { 41992a9e4f7SAdrian Hunter struct thread_stack_entry *tse = &ts->stack[0]; 42092a9e4f7SAdrian Hunter 42192a9e4f7SAdrian Hunter if (tse->cp->sym == sym) 42292a9e4f7SAdrian Hunter return thread_stack__call_return(thread, ts, --ts->cnt, 42392a9e4f7SAdrian Hunter timestamp, ref, false); 42492a9e4f7SAdrian Hunter } 42592a9e4f7SAdrian Hunter 42692a9e4f7SAdrian Hunter if (ts->stack[ts->cnt - 1].ret_addr == ret_addr) { 42792a9e4f7SAdrian Hunter return thread_stack__call_return(thread, ts, --ts->cnt, 42892a9e4f7SAdrian Hunter timestamp, ref, false); 42992a9e4f7SAdrian Hunter } else { 43092a9e4f7SAdrian Hunter size_t i = ts->cnt - 1; 43192a9e4f7SAdrian Hunter 43292a9e4f7SAdrian Hunter while (i--) { 43392a9e4f7SAdrian Hunter if (ts->stack[i].ret_addr != ret_addr) 43492a9e4f7SAdrian Hunter continue; 43592a9e4f7SAdrian Hunter i += 1; 43692a9e4f7SAdrian Hunter while (ts->cnt > i) { 43792a9e4f7SAdrian Hunter err = thread_stack__call_return(thread, ts, 43892a9e4f7SAdrian Hunter --ts->cnt, 43992a9e4f7SAdrian Hunter timestamp, ref, 44092a9e4f7SAdrian Hunter true); 44192a9e4f7SAdrian Hunter if (err) 44292a9e4f7SAdrian Hunter return err; 44392a9e4f7SAdrian Hunter } 44492a9e4f7SAdrian Hunter return thread_stack__call_return(thread, ts, --ts->cnt, 44592a9e4f7SAdrian Hunter timestamp, ref, false); 44692a9e4f7SAdrian Hunter } 44792a9e4f7SAdrian Hunter } 44892a9e4f7SAdrian Hunter 44992a9e4f7SAdrian Hunter return 1; 45092a9e4f7SAdrian Hunter } 45192a9e4f7SAdrian Hunter 45292a9e4f7SAdrian Hunter static int thread_stack__bottom(struct thread *thread, struct thread_stack *ts, 45392a9e4f7SAdrian Hunter struct perf_sample *sample, 45492a9e4f7SAdrian Hunter struct addr_location *from_al, 45592a9e4f7SAdrian Hunter struct addr_location *to_al, u64 ref) 45692a9e4f7SAdrian Hunter { 45792a9e4f7SAdrian Hunter struct call_path_root *cpr = ts->crp->cpr; 45892a9e4f7SAdrian Hunter struct call_path *cp; 45992a9e4f7SAdrian Hunter struct symbol *sym; 46092a9e4f7SAdrian Hunter u64 ip; 46192a9e4f7SAdrian Hunter 46292a9e4f7SAdrian Hunter if (sample->ip) { 46392a9e4f7SAdrian Hunter ip = sample->ip; 46492a9e4f7SAdrian Hunter sym = from_al->sym; 46592a9e4f7SAdrian Hunter } else if (sample->addr) { 46692a9e4f7SAdrian Hunter ip = sample->addr; 46792a9e4f7SAdrian Hunter sym = to_al->sym; 46892a9e4f7SAdrian Hunter } else { 46992a9e4f7SAdrian Hunter return 0; 47092a9e4f7SAdrian Hunter } 47192a9e4f7SAdrian Hunter 47292a9e4f7SAdrian Hunter cp = call_path__findnew(cpr, &cpr->call_path, sym, ip, 47392a9e4f7SAdrian Hunter ts->kernel_start); 47492a9e4f7SAdrian Hunter if (!cp) 47592a9e4f7SAdrian Hunter return -ENOMEM; 47692a9e4f7SAdrian Hunter 47792a9e4f7SAdrian Hunter return thread_stack__push_cp(thread->ts, ip, sample->time, ref, cp, 4782dcde4e1SAdrian Hunter true, false); 47992a9e4f7SAdrian Hunter } 48092a9e4f7SAdrian Hunter 48192a9e4f7SAdrian Hunter static int thread_stack__no_call_return(struct thread *thread, 48292a9e4f7SAdrian Hunter struct thread_stack *ts, 48392a9e4f7SAdrian Hunter struct perf_sample *sample, 48492a9e4f7SAdrian Hunter struct addr_location *from_al, 48592a9e4f7SAdrian Hunter struct addr_location *to_al, u64 ref) 48692a9e4f7SAdrian Hunter { 48792a9e4f7SAdrian Hunter struct call_path_root *cpr = ts->crp->cpr; 48892a9e4f7SAdrian Hunter struct call_path *cp, *parent; 48992a9e4f7SAdrian Hunter u64 ks = ts->kernel_start; 49092a9e4f7SAdrian Hunter int err; 49192a9e4f7SAdrian Hunter 49292a9e4f7SAdrian Hunter if (sample->ip >= ks && sample->addr < ks) { 49392a9e4f7SAdrian Hunter /* Return to userspace, so pop all kernel addresses */ 49492a9e4f7SAdrian Hunter while (thread_stack__in_kernel(ts)) { 49592a9e4f7SAdrian Hunter err = thread_stack__call_return(thread, ts, --ts->cnt, 49692a9e4f7SAdrian Hunter sample->time, ref, 49792a9e4f7SAdrian Hunter true); 49892a9e4f7SAdrian Hunter if (err) 49992a9e4f7SAdrian Hunter return err; 50092a9e4f7SAdrian Hunter } 50192a9e4f7SAdrian Hunter 50292a9e4f7SAdrian Hunter /* If the stack is empty, push the userspace address */ 50392a9e4f7SAdrian Hunter if (!ts->cnt) { 50492a9e4f7SAdrian Hunter cp = call_path__findnew(cpr, &cpr->call_path, 50592a9e4f7SAdrian Hunter to_al->sym, sample->addr, 50692a9e4f7SAdrian Hunter ts->kernel_start); 50792a9e4f7SAdrian Hunter if (!cp) 50892a9e4f7SAdrian Hunter return -ENOMEM; 50992a9e4f7SAdrian Hunter return thread_stack__push_cp(ts, 0, sample->time, ref, 5102dcde4e1SAdrian Hunter cp, true, false); 51192a9e4f7SAdrian Hunter } 51292a9e4f7SAdrian Hunter } else if (thread_stack__in_kernel(ts) && sample->ip < ks) { 51392a9e4f7SAdrian Hunter /* Return to userspace, so pop all kernel addresses */ 51492a9e4f7SAdrian Hunter while (thread_stack__in_kernel(ts)) { 51592a9e4f7SAdrian Hunter err = thread_stack__call_return(thread, ts, --ts->cnt, 51692a9e4f7SAdrian Hunter sample->time, ref, 51792a9e4f7SAdrian Hunter true); 51892a9e4f7SAdrian Hunter if (err) 51992a9e4f7SAdrian Hunter return err; 52092a9e4f7SAdrian Hunter } 52192a9e4f7SAdrian Hunter } 52292a9e4f7SAdrian Hunter 52392a9e4f7SAdrian Hunter if (ts->cnt) 52492a9e4f7SAdrian Hunter parent = ts->stack[ts->cnt - 1].cp; 52592a9e4f7SAdrian Hunter else 52692a9e4f7SAdrian Hunter parent = &cpr->call_path; 52792a9e4f7SAdrian Hunter 52892a9e4f7SAdrian Hunter /* This 'return' had no 'call', so push and pop top of stack */ 52992a9e4f7SAdrian Hunter cp = call_path__findnew(cpr, parent, from_al->sym, sample->ip, 53092a9e4f7SAdrian Hunter ts->kernel_start); 53192a9e4f7SAdrian Hunter if (!cp) 53292a9e4f7SAdrian Hunter return -ENOMEM; 53392a9e4f7SAdrian Hunter 53492a9e4f7SAdrian Hunter err = thread_stack__push_cp(ts, sample->addr, sample->time, ref, cp, 5352dcde4e1SAdrian Hunter true, false); 53692a9e4f7SAdrian Hunter if (err) 53792a9e4f7SAdrian Hunter return err; 53892a9e4f7SAdrian Hunter 53992a9e4f7SAdrian Hunter return thread_stack__pop_cp(thread, ts, sample->addr, sample->time, ref, 54092a9e4f7SAdrian Hunter to_al->sym); 54192a9e4f7SAdrian Hunter } 54292a9e4f7SAdrian Hunter 54392a9e4f7SAdrian Hunter static int thread_stack__trace_begin(struct thread *thread, 54492a9e4f7SAdrian Hunter struct thread_stack *ts, u64 timestamp, 54592a9e4f7SAdrian Hunter u64 ref) 54692a9e4f7SAdrian Hunter { 54792a9e4f7SAdrian Hunter struct thread_stack_entry *tse; 54892a9e4f7SAdrian Hunter int err; 54992a9e4f7SAdrian Hunter 55092a9e4f7SAdrian Hunter if (!ts->cnt) 55192a9e4f7SAdrian Hunter return 0; 55292a9e4f7SAdrian Hunter 55392a9e4f7SAdrian Hunter /* Pop trace end */ 55492a9e4f7SAdrian Hunter tse = &ts->stack[ts->cnt - 1]; 5552dcde4e1SAdrian Hunter if (tse->trace_end) { 55692a9e4f7SAdrian Hunter err = thread_stack__call_return(thread, ts, --ts->cnt, 55792a9e4f7SAdrian Hunter timestamp, ref, false); 55892a9e4f7SAdrian Hunter if (err) 55992a9e4f7SAdrian Hunter return err; 56092a9e4f7SAdrian Hunter } 56192a9e4f7SAdrian Hunter 56292a9e4f7SAdrian Hunter return 0; 56392a9e4f7SAdrian Hunter } 56492a9e4f7SAdrian Hunter 56592a9e4f7SAdrian Hunter static int thread_stack__trace_end(struct thread_stack *ts, 56692a9e4f7SAdrian Hunter struct perf_sample *sample, u64 ref) 56792a9e4f7SAdrian Hunter { 56892a9e4f7SAdrian Hunter struct call_path_root *cpr = ts->crp->cpr; 56992a9e4f7SAdrian Hunter struct call_path *cp; 57092a9e4f7SAdrian Hunter u64 ret_addr; 57192a9e4f7SAdrian Hunter 57292a9e4f7SAdrian Hunter /* No point having 'trace end' on the bottom of the stack */ 57392a9e4f7SAdrian Hunter if (!ts->cnt || (ts->cnt == 1 && ts->stack[0].ref == ref)) 57492a9e4f7SAdrian Hunter return 0; 57592a9e4f7SAdrian Hunter 57692a9e4f7SAdrian Hunter cp = call_path__findnew(cpr, ts->stack[ts->cnt - 1].cp, NULL, 0, 57792a9e4f7SAdrian Hunter ts->kernel_start); 57892a9e4f7SAdrian Hunter if (!cp) 57992a9e4f7SAdrian Hunter return -ENOMEM; 58092a9e4f7SAdrian Hunter 58192a9e4f7SAdrian Hunter ret_addr = sample->ip + sample->insn_len; 58292a9e4f7SAdrian Hunter 58392a9e4f7SAdrian Hunter return thread_stack__push_cp(ts, ret_addr, sample->time, ref, cp, 5842dcde4e1SAdrian Hunter false, true); 58592a9e4f7SAdrian Hunter } 58692a9e4f7SAdrian Hunter 58792a9e4f7SAdrian Hunter int thread_stack__process(struct thread *thread, struct comm *comm, 58892a9e4f7SAdrian Hunter struct perf_sample *sample, 58992a9e4f7SAdrian Hunter struct addr_location *from_al, 59092a9e4f7SAdrian Hunter struct addr_location *to_al, u64 ref, 59192a9e4f7SAdrian Hunter struct call_return_processor *crp) 59292a9e4f7SAdrian Hunter { 59392a9e4f7SAdrian Hunter struct thread_stack *ts = thread->ts; 59492a9e4f7SAdrian Hunter int err = 0; 59592a9e4f7SAdrian Hunter 59692a9e4f7SAdrian Hunter if (ts) { 59792a9e4f7SAdrian Hunter if (!ts->crp) { 59892a9e4f7SAdrian Hunter /* Supersede thread_stack__event() */ 59992a9e4f7SAdrian Hunter thread_stack__free(thread); 60092a9e4f7SAdrian Hunter thread->ts = thread_stack__new(thread, crp); 60192a9e4f7SAdrian Hunter if (!thread->ts) 60292a9e4f7SAdrian Hunter return -ENOMEM; 60392a9e4f7SAdrian Hunter ts = thread->ts; 60492a9e4f7SAdrian Hunter ts->comm = comm; 60592a9e4f7SAdrian Hunter } 60692a9e4f7SAdrian Hunter } else { 60792a9e4f7SAdrian Hunter thread->ts = thread_stack__new(thread, crp); 60892a9e4f7SAdrian Hunter if (!thread->ts) 60992a9e4f7SAdrian Hunter return -ENOMEM; 61092a9e4f7SAdrian Hunter ts = thread->ts; 61192a9e4f7SAdrian Hunter ts->comm = comm; 61292a9e4f7SAdrian Hunter } 61392a9e4f7SAdrian Hunter 61492a9e4f7SAdrian Hunter /* Flush stack on exec */ 61592a9e4f7SAdrian Hunter if (ts->comm != comm && thread->pid_ == thread->tid) { 616a5499b37SAdrian Hunter err = __thread_stack__flush(thread, ts); 61792a9e4f7SAdrian Hunter if (err) 61892a9e4f7SAdrian Hunter return err; 61992a9e4f7SAdrian Hunter ts->comm = comm; 62092a9e4f7SAdrian Hunter } 62192a9e4f7SAdrian Hunter 62292a9e4f7SAdrian Hunter /* If the stack is empty, put the current symbol on the stack */ 62392a9e4f7SAdrian Hunter if (!ts->cnt) { 62492a9e4f7SAdrian Hunter err = thread_stack__bottom(thread, ts, sample, from_al, to_al, 62592a9e4f7SAdrian Hunter ref); 62692a9e4f7SAdrian Hunter if (err) 62792a9e4f7SAdrian Hunter return err; 62892a9e4f7SAdrian Hunter } 62992a9e4f7SAdrian Hunter 63092a9e4f7SAdrian Hunter ts->branch_count += 1; 63192a9e4f7SAdrian Hunter ts->last_time = sample->time; 63292a9e4f7SAdrian Hunter 63392a9e4f7SAdrian Hunter if (sample->flags & PERF_IP_FLAG_CALL) { 6342dcde4e1SAdrian Hunter bool trace_end = sample->flags & PERF_IP_FLAG_TRACE_END; 63592a9e4f7SAdrian Hunter struct call_path_root *cpr = ts->crp->cpr; 63692a9e4f7SAdrian Hunter struct call_path *cp; 63792a9e4f7SAdrian Hunter u64 ret_addr; 63892a9e4f7SAdrian Hunter 63992a9e4f7SAdrian Hunter if (!sample->ip || !sample->addr) 64092a9e4f7SAdrian Hunter return 0; 64192a9e4f7SAdrian Hunter 64292a9e4f7SAdrian Hunter ret_addr = sample->ip + sample->insn_len; 64392a9e4f7SAdrian Hunter if (ret_addr == sample->addr) 64492a9e4f7SAdrian Hunter return 0; /* Zero-length calls are excluded */ 64592a9e4f7SAdrian Hunter 64692a9e4f7SAdrian Hunter cp = call_path__findnew(cpr, ts->stack[ts->cnt - 1].cp, 64792a9e4f7SAdrian Hunter to_al->sym, sample->addr, 64892a9e4f7SAdrian Hunter ts->kernel_start); 64992a9e4f7SAdrian Hunter if (!cp) 65092a9e4f7SAdrian Hunter return -ENOMEM; 65192a9e4f7SAdrian Hunter err = thread_stack__push_cp(ts, ret_addr, sample->time, ref, 6522dcde4e1SAdrian Hunter cp, false, trace_end); 65392a9e4f7SAdrian Hunter } else if (sample->flags & PERF_IP_FLAG_RETURN) { 65492a9e4f7SAdrian Hunter if (!sample->ip || !sample->addr) 65592a9e4f7SAdrian Hunter return 0; 65692a9e4f7SAdrian Hunter 65792a9e4f7SAdrian Hunter err = thread_stack__pop_cp(thread, ts, sample->addr, 65892a9e4f7SAdrian Hunter sample->time, ref, from_al->sym); 65992a9e4f7SAdrian Hunter if (err) { 66092a9e4f7SAdrian Hunter if (err < 0) 66192a9e4f7SAdrian Hunter return err; 66292a9e4f7SAdrian Hunter err = thread_stack__no_call_return(thread, ts, sample, 66392a9e4f7SAdrian Hunter from_al, to_al, ref); 66492a9e4f7SAdrian Hunter } 66592a9e4f7SAdrian Hunter } else if (sample->flags & PERF_IP_FLAG_TRACE_BEGIN) { 66692a9e4f7SAdrian Hunter err = thread_stack__trace_begin(thread, ts, sample->time, ref); 66792a9e4f7SAdrian Hunter } else if (sample->flags & PERF_IP_FLAG_TRACE_END) { 66892a9e4f7SAdrian Hunter err = thread_stack__trace_end(ts, sample, ref); 66992a9e4f7SAdrian Hunter } 67092a9e4f7SAdrian Hunter 67192a9e4f7SAdrian Hunter return err; 67292a9e4f7SAdrian Hunter } 673e216708dSAdrian Hunter 674e216708dSAdrian Hunter size_t thread_stack__depth(struct thread *thread) 675e216708dSAdrian Hunter { 676e216708dSAdrian Hunter if (!thread->ts) 677e216708dSAdrian Hunter return 0; 678e216708dSAdrian Hunter return thread->ts->cnt; 679e216708dSAdrian Hunter } 680