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> 1800447ccdSAdrian Hunter #include "thread.h" 1900447ccdSAdrian Hunter #include "event.h" 2092a9e4f7SAdrian Hunter #include "machine.h" 2100447ccdSAdrian Hunter #include "util.h" 2200447ccdSAdrian Hunter #include "debug.h" 2392a9e4f7SAdrian Hunter #include "symbol.h" 2492a9e4f7SAdrian Hunter #include "comm.h" 25451db126SChris Phlipot #include "call-path.h" 2600447ccdSAdrian Hunter #include "thread-stack.h" 2700447ccdSAdrian Hunter 2892a9e4f7SAdrian Hunter /** 2992a9e4f7SAdrian Hunter * struct call_return_processor - provides a call-back to consume call-return 3092a9e4f7SAdrian Hunter * information. 3192a9e4f7SAdrian Hunter * @cpr: call path root 3292a9e4f7SAdrian Hunter * @process: call-back that accepts call/return information 3392a9e4f7SAdrian Hunter * @data: anonymous data for call-back 3492a9e4f7SAdrian Hunter */ 3592a9e4f7SAdrian Hunter struct call_return_processor { 3692a9e4f7SAdrian Hunter struct call_path_root *cpr; 3792a9e4f7SAdrian Hunter int (*process)(struct call_return *cr, void *data); 3892a9e4f7SAdrian Hunter void *data; 3992a9e4f7SAdrian Hunter }; 4092a9e4f7SAdrian Hunter 4192a9e4f7SAdrian Hunter #define STACK_GROWTH 2048 4292a9e4f7SAdrian Hunter 4392a9e4f7SAdrian Hunter /** 4492a9e4f7SAdrian Hunter * struct thread_stack_entry - thread stack entry. 4592a9e4f7SAdrian Hunter * @ret_addr: return address 4692a9e4f7SAdrian Hunter * @timestamp: timestamp (if known) 4792a9e4f7SAdrian Hunter * @ref: external reference (e.g. db_id of sample) 4892a9e4f7SAdrian Hunter * @branch_count: the branch count when the entry was created 4992a9e4f7SAdrian Hunter * @cp: call path 5092a9e4f7SAdrian Hunter * @no_call: a 'call' was not seen 5192a9e4f7SAdrian Hunter */ 5292a9e4f7SAdrian Hunter struct thread_stack_entry { 5392a9e4f7SAdrian Hunter u64 ret_addr; 5492a9e4f7SAdrian Hunter u64 timestamp; 5592a9e4f7SAdrian Hunter u64 ref; 5692a9e4f7SAdrian Hunter u64 branch_count; 5792a9e4f7SAdrian Hunter struct call_path *cp; 5892a9e4f7SAdrian Hunter bool no_call; 5992a9e4f7SAdrian Hunter }; 6092a9e4f7SAdrian Hunter 6192a9e4f7SAdrian Hunter /** 6292a9e4f7SAdrian Hunter * struct thread_stack - thread stack constructed from 'call' and 'return' 6392a9e4f7SAdrian Hunter * branch samples. 6492a9e4f7SAdrian Hunter * @stack: array that holds the stack 6592a9e4f7SAdrian Hunter * @cnt: number of entries in the stack 6692a9e4f7SAdrian Hunter * @sz: current maximum stack size 6792a9e4f7SAdrian Hunter * @trace_nr: current trace number 6892a9e4f7SAdrian Hunter * @branch_count: running branch count 6992a9e4f7SAdrian Hunter * @kernel_start: kernel start address 7092a9e4f7SAdrian Hunter * @last_time: last timestamp 7192a9e4f7SAdrian Hunter * @crp: call/return processor 7292a9e4f7SAdrian Hunter * @comm: current comm 7392a9e4f7SAdrian Hunter */ 7400447ccdSAdrian Hunter struct thread_stack { 7500447ccdSAdrian Hunter struct thread_stack_entry *stack; 7600447ccdSAdrian Hunter size_t cnt; 7700447ccdSAdrian Hunter size_t sz; 7800447ccdSAdrian Hunter u64 trace_nr; 7992a9e4f7SAdrian Hunter u64 branch_count; 8092a9e4f7SAdrian Hunter u64 kernel_start; 8192a9e4f7SAdrian Hunter u64 last_time; 8292a9e4f7SAdrian Hunter struct call_return_processor *crp; 8392a9e4f7SAdrian Hunter struct comm *comm; 8400447ccdSAdrian Hunter }; 8500447ccdSAdrian Hunter 8600447ccdSAdrian Hunter static int thread_stack__grow(struct thread_stack *ts) 8700447ccdSAdrian Hunter { 8800447ccdSAdrian Hunter struct thread_stack_entry *new_stack; 8900447ccdSAdrian Hunter size_t sz, new_sz; 9000447ccdSAdrian Hunter 9100447ccdSAdrian Hunter new_sz = ts->sz + STACK_GROWTH; 9200447ccdSAdrian Hunter sz = new_sz * sizeof(struct thread_stack_entry); 9300447ccdSAdrian Hunter 9400447ccdSAdrian Hunter new_stack = realloc(ts->stack, sz); 9500447ccdSAdrian Hunter if (!new_stack) 9600447ccdSAdrian Hunter return -ENOMEM; 9700447ccdSAdrian Hunter 9800447ccdSAdrian Hunter ts->stack = new_stack; 9900447ccdSAdrian Hunter ts->sz = new_sz; 10000447ccdSAdrian Hunter 10100447ccdSAdrian Hunter return 0; 10200447ccdSAdrian Hunter } 10300447ccdSAdrian Hunter 10492a9e4f7SAdrian Hunter static struct thread_stack *thread_stack__new(struct thread *thread, 10592a9e4f7SAdrian Hunter struct call_return_processor *crp) 10600447ccdSAdrian Hunter { 10700447ccdSAdrian Hunter struct thread_stack *ts; 10800447ccdSAdrian Hunter 10900447ccdSAdrian Hunter ts = zalloc(sizeof(struct thread_stack)); 11000447ccdSAdrian Hunter if (!ts) 11100447ccdSAdrian Hunter return NULL; 11200447ccdSAdrian Hunter 11300447ccdSAdrian Hunter if (thread_stack__grow(ts)) { 11400447ccdSAdrian Hunter free(ts); 11500447ccdSAdrian Hunter return NULL; 11600447ccdSAdrian Hunter } 11700447ccdSAdrian Hunter 11892a9e4f7SAdrian Hunter if (thread->mg && thread->mg->machine) 11992a9e4f7SAdrian Hunter ts->kernel_start = machine__kernel_start(thread->mg->machine); 12092a9e4f7SAdrian Hunter else 12192a9e4f7SAdrian Hunter ts->kernel_start = 1ULL << 63; 12292a9e4f7SAdrian Hunter ts->crp = crp; 12392a9e4f7SAdrian Hunter 12400447ccdSAdrian Hunter return ts; 12500447ccdSAdrian Hunter } 12600447ccdSAdrian Hunter 12700447ccdSAdrian Hunter static int thread_stack__push(struct thread_stack *ts, u64 ret_addr) 12800447ccdSAdrian Hunter { 12900447ccdSAdrian Hunter int err = 0; 13000447ccdSAdrian Hunter 13100447ccdSAdrian Hunter if (ts->cnt == ts->sz) { 13200447ccdSAdrian Hunter err = thread_stack__grow(ts); 13300447ccdSAdrian Hunter if (err) { 13400447ccdSAdrian Hunter pr_warning("Out of memory: discarding thread stack\n"); 13500447ccdSAdrian Hunter ts->cnt = 0; 13600447ccdSAdrian Hunter } 13700447ccdSAdrian Hunter } 13800447ccdSAdrian Hunter 13900447ccdSAdrian Hunter ts->stack[ts->cnt++].ret_addr = ret_addr; 14000447ccdSAdrian Hunter 14100447ccdSAdrian Hunter return err; 14200447ccdSAdrian Hunter } 14300447ccdSAdrian Hunter 14400447ccdSAdrian Hunter static void thread_stack__pop(struct thread_stack *ts, u64 ret_addr) 14500447ccdSAdrian Hunter { 14600447ccdSAdrian Hunter size_t i; 14700447ccdSAdrian Hunter 14800447ccdSAdrian Hunter /* 14900447ccdSAdrian Hunter * In some cases there may be functions which are not seen to return. 15000447ccdSAdrian Hunter * For example when setjmp / longjmp has been used. Or the perf context 15100447ccdSAdrian Hunter * switch in the kernel which doesn't stop and start tracing in exactly 15200447ccdSAdrian Hunter * the same code path. When that happens the return address will be 15300447ccdSAdrian Hunter * further down the stack. If the return address is not found at all, 15400447ccdSAdrian Hunter * we assume the opposite (i.e. this is a return for a call that wasn't 15500447ccdSAdrian Hunter * seen for some reason) and leave the stack alone. 15600447ccdSAdrian Hunter */ 15700447ccdSAdrian Hunter for (i = ts->cnt; i; ) { 15800447ccdSAdrian Hunter if (ts->stack[--i].ret_addr == ret_addr) { 15900447ccdSAdrian Hunter ts->cnt = i; 16000447ccdSAdrian Hunter return; 16100447ccdSAdrian Hunter } 16200447ccdSAdrian Hunter } 16300447ccdSAdrian Hunter } 16400447ccdSAdrian Hunter 16592a9e4f7SAdrian Hunter static bool thread_stack__in_kernel(struct thread_stack *ts) 16692a9e4f7SAdrian Hunter { 16792a9e4f7SAdrian Hunter if (!ts->cnt) 16892a9e4f7SAdrian Hunter return false; 16992a9e4f7SAdrian Hunter 17092a9e4f7SAdrian Hunter return ts->stack[ts->cnt - 1].cp->in_kernel; 17192a9e4f7SAdrian Hunter } 17292a9e4f7SAdrian Hunter 17392a9e4f7SAdrian Hunter static int thread_stack__call_return(struct thread *thread, 17492a9e4f7SAdrian Hunter struct thread_stack *ts, size_t idx, 17592a9e4f7SAdrian Hunter u64 timestamp, u64 ref, bool no_return) 17692a9e4f7SAdrian Hunter { 17792a9e4f7SAdrian Hunter struct call_return_processor *crp = ts->crp; 17892a9e4f7SAdrian Hunter struct thread_stack_entry *tse; 17992a9e4f7SAdrian Hunter struct call_return cr = { 18092a9e4f7SAdrian Hunter .thread = thread, 18192a9e4f7SAdrian Hunter .comm = ts->comm, 18292a9e4f7SAdrian Hunter .db_id = 0, 18392a9e4f7SAdrian Hunter }; 18492a9e4f7SAdrian Hunter 18592a9e4f7SAdrian Hunter tse = &ts->stack[idx]; 18692a9e4f7SAdrian Hunter cr.cp = tse->cp; 18792a9e4f7SAdrian Hunter cr.call_time = tse->timestamp; 18892a9e4f7SAdrian Hunter cr.return_time = timestamp; 18992a9e4f7SAdrian Hunter cr.branch_count = ts->branch_count - tse->branch_count; 19092a9e4f7SAdrian Hunter cr.call_ref = tse->ref; 19192a9e4f7SAdrian Hunter cr.return_ref = ref; 19292a9e4f7SAdrian Hunter if (tse->no_call) 19392a9e4f7SAdrian Hunter cr.flags |= CALL_RETURN_NO_CALL; 19492a9e4f7SAdrian Hunter if (no_return) 19592a9e4f7SAdrian Hunter cr.flags |= CALL_RETURN_NO_RETURN; 19692a9e4f7SAdrian Hunter 19792a9e4f7SAdrian Hunter return crp->process(&cr, crp->data); 19892a9e4f7SAdrian Hunter } 19992a9e4f7SAdrian Hunter 200a5499b37SAdrian Hunter static int __thread_stack__flush(struct thread *thread, struct thread_stack *ts) 20192a9e4f7SAdrian Hunter { 20292a9e4f7SAdrian Hunter struct call_return_processor *crp = ts->crp; 20392a9e4f7SAdrian Hunter int err; 20492a9e4f7SAdrian Hunter 20592a9e4f7SAdrian Hunter if (!crp) { 20692a9e4f7SAdrian Hunter ts->cnt = 0; 20792a9e4f7SAdrian Hunter return 0; 20892a9e4f7SAdrian Hunter } 20992a9e4f7SAdrian Hunter 21092a9e4f7SAdrian Hunter while (ts->cnt) { 21192a9e4f7SAdrian Hunter err = thread_stack__call_return(thread, ts, --ts->cnt, 21292a9e4f7SAdrian Hunter ts->last_time, 0, true); 21392a9e4f7SAdrian Hunter if (err) { 21492a9e4f7SAdrian Hunter pr_err("Error flushing thread stack!\n"); 21592a9e4f7SAdrian Hunter ts->cnt = 0; 21692a9e4f7SAdrian Hunter return err; 21792a9e4f7SAdrian Hunter } 21892a9e4f7SAdrian Hunter } 21992a9e4f7SAdrian Hunter 22092a9e4f7SAdrian Hunter return 0; 22192a9e4f7SAdrian Hunter } 22292a9e4f7SAdrian Hunter 223a5499b37SAdrian Hunter int thread_stack__flush(struct thread *thread) 224a5499b37SAdrian Hunter { 225a5499b37SAdrian Hunter if (thread->ts) 226a5499b37SAdrian Hunter return __thread_stack__flush(thread, thread->ts); 227a5499b37SAdrian Hunter 228a5499b37SAdrian Hunter return 0; 229a5499b37SAdrian Hunter } 230a5499b37SAdrian Hunter 23100447ccdSAdrian Hunter int thread_stack__event(struct thread *thread, u32 flags, u64 from_ip, 23200447ccdSAdrian Hunter u64 to_ip, u16 insn_len, u64 trace_nr) 23300447ccdSAdrian Hunter { 23400447ccdSAdrian Hunter if (!thread) 23500447ccdSAdrian Hunter return -EINVAL; 23600447ccdSAdrian Hunter 23700447ccdSAdrian Hunter if (!thread->ts) { 23892a9e4f7SAdrian Hunter thread->ts = thread_stack__new(thread, NULL); 23900447ccdSAdrian Hunter if (!thread->ts) { 24000447ccdSAdrian Hunter pr_warning("Out of memory: no thread stack\n"); 24100447ccdSAdrian Hunter return -ENOMEM; 24200447ccdSAdrian Hunter } 24300447ccdSAdrian Hunter thread->ts->trace_nr = trace_nr; 24400447ccdSAdrian Hunter } 24500447ccdSAdrian Hunter 24600447ccdSAdrian Hunter /* 24700447ccdSAdrian Hunter * When the trace is discontinuous, the trace_nr changes. In that case 24800447ccdSAdrian Hunter * the stack might be completely invalid. Better to report nothing than 24992a9e4f7SAdrian Hunter * to report something misleading, so flush the stack. 25000447ccdSAdrian Hunter */ 25100447ccdSAdrian Hunter if (trace_nr != thread->ts->trace_nr) { 25292a9e4f7SAdrian Hunter if (thread->ts->trace_nr) 253a5499b37SAdrian Hunter __thread_stack__flush(thread, thread->ts); 25400447ccdSAdrian Hunter thread->ts->trace_nr = trace_nr; 25500447ccdSAdrian Hunter } 25600447ccdSAdrian Hunter 25792a9e4f7SAdrian Hunter /* Stop here if thread_stack__process() is in use */ 25892a9e4f7SAdrian Hunter if (thread->ts->crp) 25992a9e4f7SAdrian Hunter return 0; 26092a9e4f7SAdrian Hunter 26100447ccdSAdrian Hunter if (flags & PERF_IP_FLAG_CALL) { 26200447ccdSAdrian Hunter u64 ret_addr; 26300447ccdSAdrian Hunter 26400447ccdSAdrian Hunter if (!to_ip) 26500447ccdSAdrian Hunter return 0; 26600447ccdSAdrian Hunter ret_addr = from_ip + insn_len; 26700447ccdSAdrian Hunter if (ret_addr == to_ip) 26800447ccdSAdrian Hunter return 0; /* Zero-length calls are excluded */ 26900447ccdSAdrian Hunter return thread_stack__push(thread->ts, ret_addr); 27000447ccdSAdrian Hunter } else if (flags & PERF_IP_FLAG_RETURN) { 27100447ccdSAdrian Hunter if (!from_ip) 27200447ccdSAdrian Hunter return 0; 27300447ccdSAdrian Hunter thread_stack__pop(thread->ts, to_ip); 27400447ccdSAdrian Hunter } 27500447ccdSAdrian Hunter 27600447ccdSAdrian Hunter return 0; 27700447ccdSAdrian Hunter } 27800447ccdSAdrian Hunter 27992a9e4f7SAdrian Hunter void thread_stack__set_trace_nr(struct thread *thread, u64 trace_nr) 28092a9e4f7SAdrian Hunter { 28192a9e4f7SAdrian Hunter if (!thread || !thread->ts) 28292a9e4f7SAdrian Hunter return; 28392a9e4f7SAdrian Hunter 28492a9e4f7SAdrian Hunter if (trace_nr != thread->ts->trace_nr) { 28592a9e4f7SAdrian Hunter if (thread->ts->trace_nr) 286a5499b37SAdrian Hunter __thread_stack__flush(thread, thread->ts); 28792a9e4f7SAdrian Hunter thread->ts->trace_nr = trace_nr; 28892a9e4f7SAdrian Hunter } 28992a9e4f7SAdrian Hunter } 29092a9e4f7SAdrian Hunter 29100447ccdSAdrian Hunter void thread_stack__free(struct thread *thread) 29200447ccdSAdrian Hunter { 29300447ccdSAdrian Hunter if (thread->ts) { 294a5499b37SAdrian Hunter __thread_stack__flush(thread, thread->ts); 29500447ccdSAdrian Hunter zfree(&thread->ts->stack); 29600447ccdSAdrian Hunter zfree(&thread->ts); 29700447ccdSAdrian Hunter } 29800447ccdSAdrian Hunter } 29900447ccdSAdrian Hunter 30000447ccdSAdrian Hunter void thread_stack__sample(struct thread *thread, struct ip_callchain *chain, 30100447ccdSAdrian Hunter size_t sz, u64 ip) 30200447ccdSAdrian Hunter { 30300447ccdSAdrian Hunter size_t i; 30400447ccdSAdrian Hunter 30500447ccdSAdrian Hunter if (!thread || !thread->ts) 30600447ccdSAdrian Hunter chain->nr = 1; 30700447ccdSAdrian Hunter else 30800447ccdSAdrian Hunter chain->nr = min(sz, thread->ts->cnt + 1); 30900447ccdSAdrian Hunter 31000447ccdSAdrian Hunter chain->ips[0] = ip; 31100447ccdSAdrian Hunter 31200447ccdSAdrian Hunter for (i = 1; i < chain->nr; i++) 31300447ccdSAdrian Hunter chain->ips[i] = thread->ts->stack[thread->ts->cnt - i].ret_addr; 31400447ccdSAdrian Hunter } 31592a9e4f7SAdrian Hunter 31692a9e4f7SAdrian Hunter struct call_return_processor * 31792a9e4f7SAdrian Hunter call_return_processor__new(int (*process)(struct call_return *cr, void *data), 31892a9e4f7SAdrian Hunter void *data) 31992a9e4f7SAdrian Hunter { 32092a9e4f7SAdrian Hunter struct call_return_processor *crp; 32192a9e4f7SAdrian Hunter 32292a9e4f7SAdrian Hunter crp = zalloc(sizeof(struct call_return_processor)); 32392a9e4f7SAdrian Hunter if (!crp) 32492a9e4f7SAdrian Hunter return NULL; 32592a9e4f7SAdrian Hunter crp->cpr = call_path_root__new(); 32692a9e4f7SAdrian Hunter if (!crp->cpr) 32792a9e4f7SAdrian Hunter goto out_free; 32892a9e4f7SAdrian Hunter crp->process = process; 32992a9e4f7SAdrian Hunter crp->data = data; 33092a9e4f7SAdrian Hunter return crp; 33192a9e4f7SAdrian Hunter 33292a9e4f7SAdrian Hunter out_free: 33392a9e4f7SAdrian Hunter free(crp); 33492a9e4f7SAdrian Hunter return NULL; 33592a9e4f7SAdrian Hunter } 33692a9e4f7SAdrian Hunter 33792a9e4f7SAdrian Hunter void call_return_processor__free(struct call_return_processor *crp) 33892a9e4f7SAdrian Hunter { 33992a9e4f7SAdrian Hunter if (crp) { 34092a9e4f7SAdrian Hunter call_path_root__free(crp->cpr); 34192a9e4f7SAdrian Hunter free(crp); 34292a9e4f7SAdrian Hunter } 34392a9e4f7SAdrian Hunter } 34492a9e4f7SAdrian Hunter 34592a9e4f7SAdrian Hunter static int thread_stack__push_cp(struct thread_stack *ts, u64 ret_addr, 34692a9e4f7SAdrian Hunter u64 timestamp, u64 ref, struct call_path *cp, 34792a9e4f7SAdrian Hunter bool no_call) 34892a9e4f7SAdrian Hunter { 34992a9e4f7SAdrian Hunter struct thread_stack_entry *tse; 35092a9e4f7SAdrian Hunter int err; 35192a9e4f7SAdrian Hunter 35292a9e4f7SAdrian Hunter if (ts->cnt == ts->sz) { 35392a9e4f7SAdrian Hunter err = thread_stack__grow(ts); 35492a9e4f7SAdrian Hunter if (err) 35592a9e4f7SAdrian Hunter return err; 35692a9e4f7SAdrian Hunter } 35792a9e4f7SAdrian Hunter 35892a9e4f7SAdrian Hunter tse = &ts->stack[ts->cnt++]; 35992a9e4f7SAdrian Hunter tse->ret_addr = ret_addr; 36092a9e4f7SAdrian Hunter tse->timestamp = timestamp; 36192a9e4f7SAdrian Hunter tse->ref = ref; 36292a9e4f7SAdrian Hunter tse->branch_count = ts->branch_count; 36392a9e4f7SAdrian Hunter tse->cp = cp; 36492a9e4f7SAdrian Hunter tse->no_call = no_call; 36592a9e4f7SAdrian Hunter 36692a9e4f7SAdrian Hunter return 0; 36792a9e4f7SAdrian Hunter } 36892a9e4f7SAdrian Hunter 36992a9e4f7SAdrian Hunter static int thread_stack__pop_cp(struct thread *thread, struct thread_stack *ts, 37092a9e4f7SAdrian Hunter u64 ret_addr, u64 timestamp, u64 ref, 37192a9e4f7SAdrian Hunter struct symbol *sym) 37292a9e4f7SAdrian Hunter { 37392a9e4f7SAdrian Hunter int err; 37492a9e4f7SAdrian Hunter 37592a9e4f7SAdrian Hunter if (!ts->cnt) 37692a9e4f7SAdrian Hunter return 1; 37792a9e4f7SAdrian Hunter 37892a9e4f7SAdrian Hunter if (ts->cnt == 1) { 37992a9e4f7SAdrian Hunter struct thread_stack_entry *tse = &ts->stack[0]; 38092a9e4f7SAdrian Hunter 38192a9e4f7SAdrian Hunter if (tse->cp->sym == sym) 38292a9e4f7SAdrian Hunter return thread_stack__call_return(thread, ts, --ts->cnt, 38392a9e4f7SAdrian Hunter timestamp, ref, false); 38492a9e4f7SAdrian Hunter } 38592a9e4f7SAdrian Hunter 38692a9e4f7SAdrian Hunter if (ts->stack[ts->cnt - 1].ret_addr == ret_addr) { 38792a9e4f7SAdrian Hunter return thread_stack__call_return(thread, ts, --ts->cnt, 38892a9e4f7SAdrian Hunter timestamp, ref, false); 38992a9e4f7SAdrian Hunter } else { 39092a9e4f7SAdrian Hunter size_t i = ts->cnt - 1; 39192a9e4f7SAdrian Hunter 39292a9e4f7SAdrian Hunter while (i--) { 39392a9e4f7SAdrian Hunter if (ts->stack[i].ret_addr != ret_addr) 39492a9e4f7SAdrian Hunter continue; 39592a9e4f7SAdrian Hunter i += 1; 39692a9e4f7SAdrian Hunter while (ts->cnt > i) { 39792a9e4f7SAdrian Hunter err = thread_stack__call_return(thread, ts, 39892a9e4f7SAdrian Hunter --ts->cnt, 39992a9e4f7SAdrian Hunter timestamp, ref, 40092a9e4f7SAdrian Hunter true); 40192a9e4f7SAdrian Hunter if (err) 40292a9e4f7SAdrian Hunter return err; 40392a9e4f7SAdrian Hunter } 40492a9e4f7SAdrian Hunter return thread_stack__call_return(thread, ts, --ts->cnt, 40592a9e4f7SAdrian Hunter timestamp, ref, false); 40692a9e4f7SAdrian Hunter } 40792a9e4f7SAdrian Hunter } 40892a9e4f7SAdrian Hunter 40992a9e4f7SAdrian Hunter return 1; 41092a9e4f7SAdrian Hunter } 41192a9e4f7SAdrian Hunter 41292a9e4f7SAdrian Hunter static int thread_stack__bottom(struct thread *thread, struct thread_stack *ts, 41392a9e4f7SAdrian Hunter struct perf_sample *sample, 41492a9e4f7SAdrian Hunter struct addr_location *from_al, 41592a9e4f7SAdrian Hunter struct addr_location *to_al, u64 ref) 41692a9e4f7SAdrian Hunter { 41792a9e4f7SAdrian Hunter struct call_path_root *cpr = ts->crp->cpr; 41892a9e4f7SAdrian Hunter struct call_path *cp; 41992a9e4f7SAdrian Hunter struct symbol *sym; 42092a9e4f7SAdrian Hunter u64 ip; 42192a9e4f7SAdrian Hunter 42292a9e4f7SAdrian Hunter if (sample->ip) { 42392a9e4f7SAdrian Hunter ip = sample->ip; 42492a9e4f7SAdrian Hunter sym = from_al->sym; 42592a9e4f7SAdrian Hunter } else if (sample->addr) { 42692a9e4f7SAdrian Hunter ip = sample->addr; 42792a9e4f7SAdrian Hunter sym = to_al->sym; 42892a9e4f7SAdrian Hunter } else { 42992a9e4f7SAdrian Hunter return 0; 43092a9e4f7SAdrian Hunter } 43192a9e4f7SAdrian Hunter 43292a9e4f7SAdrian Hunter cp = call_path__findnew(cpr, &cpr->call_path, sym, ip, 43392a9e4f7SAdrian Hunter ts->kernel_start); 43492a9e4f7SAdrian Hunter if (!cp) 43592a9e4f7SAdrian Hunter return -ENOMEM; 43692a9e4f7SAdrian Hunter 43792a9e4f7SAdrian Hunter return thread_stack__push_cp(thread->ts, ip, sample->time, ref, cp, 43892a9e4f7SAdrian Hunter true); 43992a9e4f7SAdrian Hunter } 44092a9e4f7SAdrian Hunter 44192a9e4f7SAdrian Hunter static int thread_stack__no_call_return(struct thread *thread, 44292a9e4f7SAdrian Hunter struct thread_stack *ts, 44392a9e4f7SAdrian Hunter struct perf_sample *sample, 44492a9e4f7SAdrian Hunter struct addr_location *from_al, 44592a9e4f7SAdrian Hunter struct addr_location *to_al, u64 ref) 44692a9e4f7SAdrian Hunter { 44792a9e4f7SAdrian Hunter struct call_path_root *cpr = ts->crp->cpr; 44892a9e4f7SAdrian Hunter struct call_path *cp, *parent; 44992a9e4f7SAdrian Hunter u64 ks = ts->kernel_start; 45092a9e4f7SAdrian Hunter int err; 45192a9e4f7SAdrian Hunter 45292a9e4f7SAdrian Hunter if (sample->ip >= ks && sample->addr < ks) { 45392a9e4f7SAdrian Hunter /* Return to userspace, so pop all kernel addresses */ 45492a9e4f7SAdrian Hunter while (thread_stack__in_kernel(ts)) { 45592a9e4f7SAdrian Hunter err = thread_stack__call_return(thread, ts, --ts->cnt, 45692a9e4f7SAdrian Hunter sample->time, ref, 45792a9e4f7SAdrian Hunter true); 45892a9e4f7SAdrian Hunter if (err) 45992a9e4f7SAdrian Hunter return err; 46092a9e4f7SAdrian Hunter } 46192a9e4f7SAdrian Hunter 46292a9e4f7SAdrian Hunter /* If the stack is empty, push the userspace address */ 46392a9e4f7SAdrian Hunter if (!ts->cnt) { 46492a9e4f7SAdrian Hunter cp = call_path__findnew(cpr, &cpr->call_path, 46592a9e4f7SAdrian Hunter to_al->sym, sample->addr, 46692a9e4f7SAdrian Hunter ts->kernel_start); 46792a9e4f7SAdrian Hunter if (!cp) 46892a9e4f7SAdrian Hunter return -ENOMEM; 46992a9e4f7SAdrian Hunter return thread_stack__push_cp(ts, 0, sample->time, ref, 47092a9e4f7SAdrian Hunter cp, true); 47192a9e4f7SAdrian Hunter } 47292a9e4f7SAdrian Hunter } else if (thread_stack__in_kernel(ts) && sample->ip < ks) { 47392a9e4f7SAdrian Hunter /* Return to userspace, so pop all kernel addresses */ 47492a9e4f7SAdrian Hunter while (thread_stack__in_kernel(ts)) { 47592a9e4f7SAdrian Hunter err = thread_stack__call_return(thread, ts, --ts->cnt, 47692a9e4f7SAdrian Hunter sample->time, ref, 47792a9e4f7SAdrian Hunter true); 47892a9e4f7SAdrian Hunter if (err) 47992a9e4f7SAdrian Hunter return err; 48092a9e4f7SAdrian Hunter } 48192a9e4f7SAdrian Hunter } 48292a9e4f7SAdrian Hunter 48392a9e4f7SAdrian Hunter if (ts->cnt) 48492a9e4f7SAdrian Hunter parent = ts->stack[ts->cnt - 1].cp; 48592a9e4f7SAdrian Hunter else 48692a9e4f7SAdrian Hunter parent = &cpr->call_path; 48792a9e4f7SAdrian Hunter 48892a9e4f7SAdrian Hunter /* This 'return' had no 'call', so push and pop top of stack */ 48992a9e4f7SAdrian Hunter cp = call_path__findnew(cpr, parent, from_al->sym, sample->ip, 49092a9e4f7SAdrian Hunter ts->kernel_start); 49192a9e4f7SAdrian Hunter if (!cp) 49292a9e4f7SAdrian Hunter return -ENOMEM; 49392a9e4f7SAdrian Hunter 49492a9e4f7SAdrian Hunter err = thread_stack__push_cp(ts, sample->addr, sample->time, ref, cp, 49592a9e4f7SAdrian Hunter true); 49692a9e4f7SAdrian Hunter if (err) 49792a9e4f7SAdrian Hunter return err; 49892a9e4f7SAdrian Hunter 49992a9e4f7SAdrian Hunter return thread_stack__pop_cp(thread, ts, sample->addr, sample->time, ref, 50092a9e4f7SAdrian Hunter to_al->sym); 50192a9e4f7SAdrian Hunter } 50292a9e4f7SAdrian Hunter 50392a9e4f7SAdrian Hunter static int thread_stack__trace_begin(struct thread *thread, 50492a9e4f7SAdrian Hunter struct thread_stack *ts, u64 timestamp, 50592a9e4f7SAdrian Hunter u64 ref) 50692a9e4f7SAdrian Hunter { 50792a9e4f7SAdrian Hunter struct thread_stack_entry *tse; 50892a9e4f7SAdrian Hunter int err; 50992a9e4f7SAdrian Hunter 51092a9e4f7SAdrian Hunter if (!ts->cnt) 51192a9e4f7SAdrian Hunter return 0; 51292a9e4f7SAdrian Hunter 51392a9e4f7SAdrian Hunter /* Pop trace end */ 51492a9e4f7SAdrian Hunter tse = &ts->stack[ts->cnt - 1]; 51592a9e4f7SAdrian Hunter if (tse->cp->sym == NULL && tse->cp->ip == 0) { 51692a9e4f7SAdrian Hunter err = thread_stack__call_return(thread, ts, --ts->cnt, 51792a9e4f7SAdrian Hunter timestamp, ref, false); 51892a9e4f7SAdrian Hunter if (err) 51992a9e4f7SAdrian Hunter return err; 52092a9e4f7SAdrian Hunter } 52192a9e4f7SAdrian Hunter 52292a9e4f7SAdrian Hunter return 0; 52392a9e4f7SAdrian Hunter } 52492a9e4f7SAdrian Hunter 52592a9e4f7SAdrian Hunter static int thread_stack__trace_end(struct thread_stack *ts, 52692a9e4f7SAdrian Hunter struct perf_sample *sample, u64 ref) 52792a9e4f7SAdrian Hunter { 52892a9e4f7SAdrian Hunter struct call_path_root *cpr = ts->crp->cpr; 52992a9e4f7SAdrian Hunter struct call_path *cp; 53092a9e4f7SAdrian Hunter u64 ret_addr; 53192a9e4f7SAdrian Hunter 53292a9e4f7SAdrian Hunter /* No point having 'trace end' on the bottom of the stack */ 53392a9e4f7SAdrian Hunter if (!ts->cnt || (ts->cnt == 1 && ts->stack[0].ref == ref)) 53492a9e4f7SAdrian Hunter return 0; 53592a9e4f7SAdrian Hunter 53692a9e4f7SAdrian Hunter cp = call_path__findnew(cpr, ts->stack[ts->cnt - 1].cp, NULL, 0, 53792a9e4f7SAdrian Hunter ts->kernel_start); 53892a9e4f7SAdrian Hunter if (!cp) 53992a9e4f7SAdrian Hunter return -ENOMEM; 54092a9e4f7SAdrian Hunter 54192a9e4f7SAdrian Hunter ret_addr = sample->ip + sample->insn_len; 54292a9e4f7SAdrian Hunter 54392a9e4f7SAdrian Hunter return thread_stack__push_cp(ts, ret_addr, sample->time, ref, cp, 54492a9e4f7SAdrian Hunter false); 54592a9e4f7SAdrian Hunter } 54692a9e4f7SAdrian Hunter 54792a9e4f7SAdrian Hunter int thread_stack__process(struct thread *thread, struct comm *comm, 54892a9e4f7SAdrian Hunter struct perf_sample *sample, 54992a9e4f7SAdrian Hunter struct addr_location *from_al, 55092a9e4f7SAdrian Hunter struct addr_location *to_al, u64 ref, 55192a9e4f7SAdrian Hunter struct call_return_processor *crp) 55292a9e4f7SAdrian Hunter { 55392a9e4f7SAdrian Hunter struct thread_stack *ts = thread->ts; 55492a9e4f7SAdrian Hunter int err = 0; 55592a9e4f7SAdrian Hunter 55692a9e4f7SAdrian Hunter if (ts) { 55792a9e4f7SAdrian Hunter if (!ts->crp) { 55892a9e4f7SAdrian Hunter /* Supersede thread_stack__event() */ 55992a9e4f7SAdrian Hunter thread_stack__free(thread); 56092a9e4f7SAdrian Hunter thread->ts = thread_stack__new(thread, crp); 56192a9e4f7SAdrian Hunter if (!thread->ts) 56292a9e4f7SAdrian Hunter return -ENOMEM; 56392a9e4f7SAdrian Hunter ts = thread->ts; 56492a9e4f7SAdrian Hunter ts->comm = comm; 56592a9e4f7SAdrian Hunter } 56692a9e4f7SAdrian Hunter } else { 56792a9e4f7SAdrian Hunter thread->ts = thread_stack__new(thread, crp); 56892a9e4f7SAdrian Hunter if (!thread->ts) 56992a9e4f7SAdrian Hunter return -ENOMEM; 57092a9e4f7SAdrian Hunter ts = thread->ts; 57192a9e4f7SAdrian Hunter ts->comm = comm; 57292a9e4f7SAdrian Hunter } 57392a9e4f7SAdrian Hunter 57492a9e4f7SAdrian Hunter /* Flush stack on exec */ 57592a9e4f7SAdrian Hunter if (ts->comm != comm && thread->pid_ == thread->tid) { 576a5499b37SAdrian Hunter err = __thread_stack__flush(thread, ts); 57792a9e4f7SAdrian Hunter if (err) 57892a9e4f7SAdrian Hunter return err; 57992a9e4f7SAdrian Hunter ts->comm = comm; 58092a9e4f7SAdrian Hunter } 58192a9e4f7SAdrian Hunter 58292a9e4f7SAdrian Hunter /* If the stack is empty, put the current symbol on the stack */ 58392a9e4f7SAdrian Hunter if (!ts->cnt) { 58492a9e4f7SAdrian Hunter err = thread_stack__bottom(thread, ts, sample, from_al, to_al, 58592a9e4f7SAdrian Hunter ref); 58692a9e4f7SAdrian Hunter if (err) 58792a9e4f7SAdrian Hunter return err; 58892a9e4f7SAdrian Hunter } 58992a9e4f7SAdrian Hunter 59092a9e4f7SAdrian Hunter ts->branch_count += 1; 59192a9e4f7SAdrian Hunter ts->last_time = sample->time; 59292a9e4f7SAdrian Hunter 59392a9e4f7SAdrian Hunter if (sample->flags & PERF_IP_FLAG_CALL) { 59492a9e4f7SAdrian Hunter struct call_path_root *cpr = ts->crp->cpr; 59592a9e4f7SAdrian Hunter struct call_path *cp; 59692a9e4f7SAdrian Hunter u64 ret_addr; 59792a9e4f7SAdrian Hunter 59892a9e4f7SAdrian Hunter if (!sample->ip || !sample->addr) 59992a9e4f7SAdrian Hunter return 0; 60092a9e4f7SAdrian Hunter 60192a9e4f7SAdrian Hunter ret_addr = sample->ip + sample->insn_len; 60292a9e4f7SAdrian Hunter if (ret_addr == sample->addr) 60392a9e4f7SAdrian Hunter return 0; /* Zero-length calls are excluded */ 60492a9e4f7SAdrian Hunter 60592a9e4f7SAdrian Hunter cp = call_path__findnew(cpr, ts->stack[ts->cnt - 1].cp, 60692a9e4f7SAdrian Hunter to_al->sym, sample->addr, 60792a9e4f7SAdrian Hunter ts->kernel_start); 60892a9e4f7SAdrian Hunter if (!cp) 60992a9e4f7SAdrian Hunter return -ENOMEM; 61092a9e4f7SAdrian Hunter err = thread_stack__push_cp(ts, ret_addr, sample->time, ref, 61192a9e4f7SAdrian Hunter cp, false); 61292a9e4f7SAdrian Hunter } else if (sample->flags & PERF_IP_FLAG_RETURN) { 61392a9e4f7SAdrian Hunter if (!sample->ip || !sample->addr) 61492a9e4f7SAdrian Hunter return 0; 61592a9e4f7SAdrian Hunter 61692a9e4f7SAdrian Hunter err = thread_stack__pop_cp(thread, ts, sample->addr, 61792a9e4f7SAdrian Hunter sample->time, ref, from_al->sym); 61892a9e4f7SAdrian Hunter if (err) { 61992a9e4f7SAdrian Hunter if (err < 0) 62092a9e4f7SAdrian Hunter return err; 62192a9e4f7SAdrian Hunter err = thread_stack__no_call_return(thread, ts, sample, 62292a9e4f7SAdrian Hunter from_al, to_al, ref); 62392a9e4f7SAdrian Hunter } 62492a9e4f7SAdrian Hunter } else if (sample->flags & PERF_IP_FLAG_TRACE_BEGIN) { 62592a9e4f7SAdrian Hunter err = thread_stack__trace_begin(thread, ts, sample->time, ref); 62692a9e4f7SAdrian Hunter } else if (sample->flags & PERF_IP_FLAG_TRACE_END) { 62792a9e4f7SAdrian Hunter err = thread_stack__trace_end(ts, sample, ref); 62892a9e4f7SAdrian Hunter } 62992a9e4f7SAdrian Hunter 63092a9e4f7SAdrian Hunter return err; 63192a9e4f7SAdrian Hunter } 632