stacktrace.cc revision 5254 
1/*
2 * Copyright (c) 2004-2005 The Regents of The University of Michigan
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Authors: Nathan Binkert
29 */
30
31#include <string>
32
33#include "arch/mips/isa_traits.hh"
34#include "arch/mips/stacktrace.hh"
35#include "arch/mips/vtophys.hh"
36#include "base/bitfield.hh"
37#include "base/trace.hh"
38#include "cpu/base.hh"
39#include "cpu/thread_context.hh"
40#include "sim/system.hh"
41
42using namespace std;
43using namespace MipsISA;
44
45ProcessInfo::ProcessInfo(ThreadContext *_tc)
46    : tc(_tc)
47{
48//     Addr addr = 0;
49
50    VirtualPort *vp;
51
52    vp = tc->getVirtPort();
53
54//     if (!tc->getSystemPtr()->kernelSymtab->findAddress("thread_info_size", addr))
55//         panic("thread info not compiled into kernel\n");
56//     thread_info_size = vp->readGtoH<int32_t>(addr);
57
58//     if (!tc->getSystemPtr()->kernelSymtab->findAddress("task_struct_size", addr))
59//         panic("thread info not compiled into kernel\n");
60//     task_struct_size = vp->readGtoH<int32_t>(addr);
61
62//     if (!tc->getSystemPtr()->kernelSymtab->findAddress("thread_info_task", addr))
63//         panic("thread info not compiled into kernel\n");
64//     task_off = vp->readGtoH<int32_t>(addr);
65
66//     if (!tc->getSystemPtr()->kernelSymtab->findAddress("task_struct_pid", addr))
67//         panic("thread info not compiled into kernel\n");
68//     pid_off = vp->readGtoH<int32_t>(addr);
69
70//     if (!tc->getSystemPtr()->kernelSymtab->findAddress("task_struct_comm", addr))
71//         panic("thread info not compiled into kernel\n");
72//     name_off = vp->readGtoH<int32_t>(addr);
73
74    tc->delVirtPort(vp);
75}
76
77Addr
78ProcessInfo::task(Addr ksp) const
79{
80    Addr base = ksp & ~0x3fff;
81    if (base == ULL(0xfffffc0000000000))
82        return 0;
83
84    Addr tsk;
85
86    VirtualPort *vp;
87
88    vp = tc->getVirtPort();
89    tsk = vp->readGtoH<Addr>(base + task_off);
90    tc->delVirtPort(vp);
91
92    return tsk;
93}
94
95int
96ProcessInfo::pid(Addr ksp) const
97{
98    Addr task = this->task(ksp);
99    if (!task)
100        return -1;
101
102    uint16_t pd;
103
104    VirtualPort *vp;
105
106    vp = tc->getVirtPort();
107    pd = vp->readGtoH<uint16_t>(task + pid_off);
108    tc->delVirtPort(vp);
109
110    return pd;
111}
112
113string
114ProcessInfo::name(Addr ksp) const
115{
116    Addr task = this->task(ksp);
117    if (!task)
118        return "console";
119
120    char comm[256];
121    CopyStringOut(tc, comm, task + name_off, sizeof(comm));
122    if (!comm[0])
123        return "startup";
124
125    return comm;
126}
127
128StackTrace::StackTrace()
129    : tc(0), stack(64)
130{
131}
132
133StackTrace::StackTrace(ThreadContext *_tc, StaticInstPtr inst)
134    : tc(0), stack(64)
135{
136    trace(_tc, inst);
137}
138
139StackTrace::~StackTrace()
140{
141}
142
143void
144StackTrace::trace(ThreadContext *_tc, bool is_call)
145{
146    tc = _tc;
147    /* FIXME - Jaidev - What is IPR_DTB_CM in Alpha? */
148    bool usermode = 0;
149      //(tc->readMiscReg(MipsISA::IPR_DTB_CM) & 0x18) != 0;
150
151//     Addr pc = tc->readNextPC();
152//     bool kernel = tc->getSystemPtr()->kernelStart <= pc &&
153//         pc <= tc->getSystemPtr()->kernelEnd;
154
155    if (usermode) {
156        stack.push_back(user);
157        return;
158    }
159
160//     if (!kernel) {
161//         stack.push_back(console);
162//         return;
163//     }
164
165//     SymbolTable *symtab = tc->getSystemPtr()->kernelSymtab;
166//     Addr ksp = tc->readIntReg(TheISA::StackPointerReg);
167//     Addr bottom = ksp & ~0x3fff;
168//     Addr addr;
169
170//     if (is_call) {
171//         if (!symtab->findNearestAddr(pc, addr))
172//             panic("could not find address %#x", pc);
173
174//         stack.push_back(addr);
175//         pc = tc->readPC();
176//     }
177
178//     Addr ra;
179//     int size;
180
181//     while (ksp > bottom) {
182//         if (!symtab->findNearestAddr(pc, addr))
183//             panic("could not find symbol for pc=%#x", pc);
184//         assert(pc >= addr && "symbol botch: callpc < func");
185
186//         stack.push_back(addr);
187
188//         if (isEntry(addr))
189//             return;
190
191//         if (decodePrologue(ksp, pc, addr, size, ra)) {
192//             if (!ra)
193//                 return;
194
195//             if (size <= 0) {
196//                 stack.push_back(unknown);
197//                 return;
198//             }
199
200//             pc = ra;
201//             ksp += size;
202//         } else {
203//             stack.push_back(unknown);
204//             return;
205//         }
206
207//         bool kernel = tc->getSystemPtr()->kernelStart <= pc &&
208//             pc <= tc->getSystemPtr()->kernelEnd;
209//         if (!kernel)
210//             return;
211
212//         if (stack.size() >= 1000)
213//             panic("unwinding too far");
214//     }
215
216//     panic("unwinding too far");
217}
218
219bool
220StackTrace::isEntry(Addr addr)
221{
222  /*    if (addr == tc->readMiscReg(MipsISA::IPR_PALtemp2))
223        return true;*/
224
225    return false;
226}
227
228bool
229StackTrace::decodeStack(MachInst inst, int &disp)
230{
231    // lda $sp, -disp($sp)
232    //
233    // Opcode<31:26> == 0x08
234    // RA<25:21> == 30
235    // RB<20:16> == 30
236    // Disp<15:0>
237    const MachInst mem_mask = 0xffff0000;
238    const MachInst lda_pattern = 0x23de0000;
239    const MachInst lda_disp_mask = 0x0000ffff;
240
241    // subq $sp, disp, $sp
242    // addq $sp, disp, $sp
243    //
244    // Opcode<31:26> == 0x10
245    // RA<25:21> == 30
246    // Lit<20:13>
247    // One<12> = 1
248    // Func<11:5> == 0x20 (addq)
249    // Func<11:5> == 0x29 (subq)
250    // RC<4:0> == 30
251    const MachInst intop_mask = 0xffe01fff;
252    const MachInst addq_pattern = 0x43c0141e;
253    const MachInst subq_pattern = 0x43c0153e;
254    const MachInst intop_disp_mask = 0x001fe000;
255    const int intop_disp_shift = 13;
256
257    if ((inst & mem_mask) == lda_pattern)
258        disp = -sext<16>(inst & lda_disp_mask);
259    else if ((inst & intop_mask) == addq_pattern)
260        disp = -int((inst & intop_disp_mask) >> intop_disp_shift);
261    else if ((inst & intop_mask) == subq_pattern)
262        disp = int((inst & intop_disp_mask) >> intop_disp_shift);
263    else
264        return false;
265
266    return true;
267}
268
269bool
270StackTrace::decodeSave(MachInst inst, int &reg, int &disp)
271{
272    // lda $stq, disp($sp)
273    //
274    // Opcode<31:26> == 0x08
275    // RA<25:21> == ?
276    // RB<20:16> == 30
277    // Disp<15:0>
278    const MachInst stq_mask = 0xfc1f0000;
279    const MachInst stq_pattern = 0xb41e0000;
280    const MachInst stq_disp_mask = 0x0000ffff;
281    const MachInst reg_mask = 0x03e00000;
282    const int reg_shift = 21;
283
284    if ((inst & stq_mask) == stq_pattern) {
285        reg = (inst & reg_mask) >> reg_shift;
286        disp = sext<16>(inst & stq_disp_mask);
287    } else {
288        return false;
289    }
290
291    return true;
292}
293
294/*
295 * Decode the function prologue for the function we're in, and note
296 * which registers are stored where, and how large the stack frame is.
297 */
298bool
299StackTrace::decodePrologue(Addr sp, Addr callpc, Addr func,
300                           int &size, Addr &ra)
301{
302    size = 0;
303    ra = 0;
304
305    for (Addr pc = func; pc < callpc; pc += sizeof(MachInst)) {
306        MachInst inst;
307        CopyOut(tc, (uint8_t *)&inst, pc, sizeof(MachInst));
308
309        int reg, disp;
310        if (decodeStack(inst, disp)) {
311            if (size) {
312                // panic("decoding frame size again");
313                return true;
314            }
315            size += disp;
316        } else if (decodeSave(inst, reg, disp)) {
317            if (!ra && reg == ReturnAddressReg) {
318                CopyOut(tc, (uint8_t *)&ra, sp + disp, sizeof(Addr));
319                if (!ra) {
320                    // panic("no return address value pc=%#x\n", pc);
321                    return false;
322                }
323            }
324        }
325    }
326
327    return true;
328}
329
330#if TRACING_ON
331void
332StackTrace::dump()
333{
334    StringWrap name(tc->getCpuPtr()->name());
335//     SymbolTable *symtab = tc->getSystemPtr()->kernelSymtab;
336
337    DPRINTFN("------ Stack ------\n");
338
339//     string symbol;
340//     for (int i = 0, size = stack.size(); i < size; ++i) {
341//         Addr addr = stack[size - i - 1];
342//         if (addr == user)
343//             symbol = "user";
344//         else if (addr == console)
345//             symbol = "console";
346//         else if (addr == unknown)
347//             symbol = "unknown";
348//         else
349//             symtab->findSymbol(addr, symbol);
350
351//         DPRINTFN("%#x: %s\n", addr, symbol);
352//     }
353}
354#endif
355