am 3adbe79d: am 66e31dc5: am 3a088524: Merge "Rewrite unwind thread handling."
* commit '3adbe79d2f14665ff55a9b0db245abebc105658d':
Rewrite unwind thread handling.
diff --git a/include/backtrace/Backtrace.h b/include/backtrace/Backtrace.h
index 3c3a482..561dfeb 100644
--- a/include/backtrace/Backtrace.h
+++ b/include/backtrace/Backtrace.h
@@ -19,6 +19,7 @@
#include <inttypes.h>
#include <stdint.h>
+#include <ucontext.h>
#include <string>
#include <vector>
@@ -64,7 +65,7 @@
virtual ~Backtrace();
// Get the current stack trace and store in the backtrace_ structure.
- virtual bool Unwind(size_t num_ignore_frames);
+ virtual bool Unwind(size_t num_ignore_frames, ucontext_t* context = NULL);
// Get the function name and offset into the function given the pc.
// If the string is empty, then no valid function name was found.
diff --git a/libbacktrace/Android.mk b/libbacktrace/Android.mk
index 7fe52ef..fa79221 100755
--- a/libbacktrace/Android.mk
+++ b/libbacktrace/Android.mk
@@ -116,6 +116,9 @@
backtrace_test_shared_libraries_target := \
libcutils \
+backtrace_test_static_libraries_host := \
+ libcutils \
+
module := backtrace_test
module_tag := debug
build_type := target
diff --git a/libbacktrace/BacktraceImpl.cpp b/libbacktrace/BacktraceImpl.cpp
index 05007d9..d7ac0b2 100644
--- a/libbacktrace/BacktraceImpl.cpp
+++ b/libbacktrace/BacktraceImpl.cpp
@@ -55,8 +55,8 @@
}
}
-bool Backtrace::Unwind(size_t num_ignore_frames) {
- return impl_->Unwind(num_ignore_frames);
+bool Backtrace::Unwind(size_t num_ignore_frames, ucontext_t* ucontext) {
+ return impl_->Unwind(num_ignore_frames, ucontext);
}
extern "C" char* __cxa_demangle(const char* mangled, char* buf, size_t* len,
diff --git a/libbacktrace/BacktraceImpl.h b/libbacktrace/BacktraceImpl.h
index 7b31c38..8ed64b3 100755
--- a/libbacktrace/BacktraceImpl.h
+++ b/libbacktrace/BacktraceImpl.h
@@ -21,12 +21,13 @@
#include <backtrace/BacktraceMap.h>
#include <sys/types.h>
+#include <ucontext.h>
class BacktraceImpl {
public:
virtual ~BacktraceImpl() { }
- virtual bool Unwind(size_t num_ignore_frames) = 0;
+ virtual bool Unwind(size_t num_ignore_frames, ucontext_t* ucontext) = 0;
// The name returned is not demangled, Backtrace::GetFunctionName()
// takes care of demangling the name.
diff --git a/libbacktrace/BacktraceThread.cpp b/libbacktrace/BacktraceThread.cpp
index e0bab24..018d51f 100644
--- a/libbacktrace/BacktraceThread.cpp
+++ b/libbacktrace/BacktraceThread.cpp
@@ -16,10 +16,15 @@
#include <errno.h>
#include <inttypes.h>
+#include <limits.h>
+#include <linux/futex.h>
#include <pthread.h>
#include <signal.h>
#include <string.h>
+#include <sys/syscall.h>
+#include <sys/time.h>
#include <sys/types.h>
+#include <ucontext.h>
#include <cutils/atomic.h>
@@ -27,190 +32,173 @@
#include "BacktraceThread.h"
#include "thread_utils.h"
+static inline int futex(volatile int* uaddr, int op, int val, const struct timespec* ts, volatile int* uaddr2, int val3) {
+ return syscall(__NR_futex, uaddr, op, val, ts, uaddr2, val3);
+}
+
//-------------------------------------------------------------------------
// ThreadEntry implementation.
//-------------------------------------------------------------------------
-static ThreadEntry* g_list = NULL;
-static pthread_mutex_t g_entry_mutex = PTHREAD_MUTEX_INITIALIZER;
-static pthread_mutex_t g_sigaction_mutex = PTHREAD_MUTEX_INITIALIZER;
+ThreadEntry* ThreadEntry::list_ = NULL;
+pthread_mutex_t ThreadEntry::list_mutex_ = PTHREAD_MUTEX_INITIALIZER;
-ThreadEntry::ThreadEntry(
- BacktraceThreadInterface* intf, pid_t pid, pid_t tid, size_t num_ignore_frames)
- : thread_intf(intf), pid(pid), tid(tid), next(NULL), prev(NULL),
- state(STATE_WAITING), num_ignore_frames(num_ignore_frames) {
+// Assumes that ThreadEntry::list_mutex_ has already been locked before
+// creating a ThreadEntry object.
+ThreadEntry::ThreadEntry(pid_t pid, pid_t tid)
+ : pid_(pid), tid_(tid), futex_(0), ref_count_(1), mutex_(PTHREAD_MUTEX_INITIALIZER), next_(ThreadEntry::list_), prev_(NULL) {
+ // Add ourselves to the list.
+ if (ThreadEntry::list_) {
+ ThreadEntry::list_->prev_ = this;
+ }
+ ThreadEntry::list_ = this;
}
-ThreadEntry::~ThreadEntry() {
- pthread_mutex_lock(&g_entry_mutex);
- if (g_list == this) {
- g_list = next;
+ThreadEntry* ThreadEntry::Get(pid_t pid, pid_t tid, bool create) {
+ pthread_mutex_lock(&ThreadEntry::list_mutex_);
+ ThreadEntry* entry = list_;
+ while (entry != NULL) {
+ if (entry->Match(pid, tid)) {
+ break;
+ }
+ entry = entry->next_;
+ }
+
+ if (!entry) {
+ if (create) {
+ entry = new ThreadEntry(pid, tid);
+ }
} else {
- if (next) {
- next->prev = prev;
- }
- prev->next = next;
+ entry->ref_count_++;
}
- pthread_mutex_unlock(&g_entry_mutex);
-
- next = NULL;
- prev = NULL;
-}
-
-ThreadEntry* ThreadEntry::AddThreadToUnwind(
- BacktraceThreadInterface* intf, pid_t pid, pid_t tid, size_t num_ignore_frames) {
- ThreadEntry* entry = new ThreadEntry(intf, pid, tid, num_ignore_frames);
-
- pthread_mutex_lock(&g_entry_mutex);
- ThreadEntry* cur_entry = g_list;
- while (cur_entry != NULL) {
- if (cur_entry->Match(pid, tid)) {
- // There is already an entry for this pid/tid, this is bad.
- BACK_LOGW("Entry for pid %d tid %d already exists.", pid, tid);
-
- pthread_mutex_unlock(&g_entry_mutex);
- return NULL;
- }
- cur_entry = cur_entry->next;
- }
-
- // Add the entry to the list.
- entry->next = g_list;
- if (g_list) {
- g_list->prev = entry;
- }
- g_list = entry;
- pthread_mutex_unlock(&g_entry_mutex);
+ pthread_mutex_unlock(&ThreadEntry::list_mutex_);
return entry;
}
+void ThreadEntry::Remove(ThreadEntry* entry) {
+ pthread_mutex_unlock(&entry->mutex_);
+
+ pthread_mutex_lock(&ThreadEntry::list_mutex_);
+ if (--entry->ref_count_ == 0) {
+ delete entry;
+ }
+ pthread_mutex_unlock(&ThreadEntry::list_mutex_);
+}
+
+// Assumes that ThreadEntry::list_mutex_ has already been locked before
+// deleting a ThreadEntry object.
+ThreadEntry::~ThreadEntry() {
+ if (list_ == this) {
+ list_ = next_;
+ } else {
+ if (next_) {
+ next_->prev_ = prev_;
+ }
+ prev_->next_ = next_;
+ }
+
+ next_ = NULL;
+ prev_ = NULL;
+}
+
+void ThreadEntry::Wait(int value) {
+ timespec ts;
+ ts.tv_sec = 10;
+ ts.tv_nsec = 0;
+ errno = 0;
+ futex(&futex_, FUTEX_WAIT, value, &ts, NULL, 0);
+ if (errno != 0 && errno != EWOULDBLOCK) {
+ BACK_LOGW("futex wait failed, futex = %d: %s", futex_, strerror(errno));
+ }
+}
+
+void ThreadEntry::Wake() {
+ futex_++;
+ futex(&futex_, FUTEX_WAKE, INT_MAX, NULL, NULL, 0);
+}
+
//-------------------------------------------------------------------------
// BacktraceThread functions.
//-------------------------------------------------------------------------
-static void SignalHandler(int n __attribute__((unused)), siginfo_t* siginfo,
- void* sigcontext) {
- if (pthread_mutex_lock(&g_entry_mutex) == 0) {
- pid_t pid = getpid();
- pid_t tid = gettid();
- ThreadEntry* cur_entry = g_list;
- while (cur_entry) {
- if (cur_entry->Match(pid, tid)) {
- break;
- }
- cur_entry = cur_entry->next;
- }
- pthread_mutex_unlock(&g_entry_mutex);
- if (!cur_entry) {
- BACK_LOGW("Unable to find pid %d tid %d information", pid, tid);
- return;
- }
+static pthread_mutex_t g_sigaction_mutex = PTHREAD_MUTEX_INITIALIZER;
- if (android_atomic_acquire_cas(STATE_WAITING, STATE_DUMPING, &cur_entry->state) == 0) {
- cur_entry->thread_intf->ThreadUnwind(siginfo, sigcontext,
- cur_entry->num_ignore_frames);
- }
- android_atomic_release_store(STATE_DONE, &cur_entry->state);
+static void SignalHandler(int, siginfo_t*, void* sigcontext) {
+ ThreadEntry* entry = ThreadEntry::Get(getpid(), gettid(), false);
+ if (!entry) {
+ BACK_LOGW("Unable to find pid %d tid %d information", getpid(), gettid());
+ return;
}
+
+ entry->CopyUcontext(reinterpret_cast<ucontext_t*>(sigcontext));
+
+ // Indicate the ucontext is now valid.
+ entry->Wake();
+
+ // Pause the thread until the unwind is complete. This avoids having
+ // the thread run ahead causing problems.
+ entry->Wait(1);
+
+ ThreadEntry::Remove(entry);
}
-BacktraceThread::BacktraceThread(
- BacktraceImpl* impl, BacktraceThreadInterface* thread_intf, pid_t tid,
- BacktraceMap* map)
- : BacktraceCurrent(impl, map), thread_intf_(thread_intf) {
+BacktraceThread::BacktraceThread(BacktraceImpl* impl, pid_t tid, BacktraceMap* map)
+ : BacktraceCurrent(impl, map) {
tid_ = tid;
}
BacktraceThread::~BacktraceThread() {
}
-void BacktraceThread::FinishUnwind() {
- for (std::vector<backtrace_frame_data_t>::iterator it = frames_.begin();
- it != frames_.end(); ++it) {
- it->map = FindMap(it->pc);
-
- it->func_offset = 0;
- it->func_name = GetFunctionName(it->pc, &it->func_offset);
- }
-}
-
-bool BacktraceThread::TriggerUnwindOnThread(ThreadEntry* entry) {
- entry->state = STATE_WAITING;
-
- if (tgkill(Pid(), Tid(), THREAD_SIGNAL) != 0) {
- BACK_LOGW("tgkill failed %s", strerror(errno));
- return false;
- }
-
- // Allow up to ten seconds for the dump to start.
- int wait_millis = 10000;
- int32_t state;
- while (true) {
- state = android_atomic_acquire_load(&entry->state);
- if (state != STATE_WAITING) {
- break;
- }
- if (wait_millis--) {
- usleep(1000);
- } else {
- break;
- }
- }
-
- bool cancelled = false;
- if (state == STATE_WAITING) {
- if (android_atomic_acquire_cas(state, STATE_CANCEL, &entry->state) == 0) {
- BACK_LOGW("Cancelled dump of thread %d", entry->tid);
- state = STATE_CANCEL;
- cancelled = true;
- } else {
- state = android_atomic_acquire_load(&entry->state);
- }
- }
-
- // Wait for at most ten seconds for the cancel or dump to finish.
- wait_millis = 10000;
- while (android_atomic_acquire_load(&entry->state) != STATE_DONE) {
- if (wait_millis--) {
- usleep(1000);
- } else {
- BACK_LOGW("Didn't finish thread unwind in 60 seconds.");
- break;
- }
- }
- return !cancelled;
-}
-
-bool BacktraceThread::Unwind(size_t num_ignore_frames) {
- ThreadEntry* entry = ThreadEntry::AddThreadToUnwind(
- thread_intf_, Pid(), Tid(), num_ignore_frames);
- if (!entry) {
- return false;
+bool BacktraceThread::Unwind(size_t num_ignore_frames, ucontext_t* ucontext) {
+ if (ucontext) {
+ // Unwind using an already existing ucontext.
+ return impl_->Unwind(num_ignore_frames, ucontext);
}
// Prevent multiple threads trying to set the trigger action on different
// threads at the same time.
- bool retval = false;
- if (pthread_mutex_lock(&g_sigaction_mutex) == 0) {
- struct sigaction act, oldact;
- memset(&act, 0, sizeof(act));
- act.sa_sigaction = SignalHandler;
- act.sa_flags = SA_RESTART | SA_SIGINFO | SA_ONSTACK;
- sigemptyset(&act.sa_mask);
- if (sigaction(THREAD_SIGNAL, &act, &oldact) == 0) {
- retval = TriggerUnwindOnThread(entry);
- sigaction(THREAD_SIGNAL, &oldact, NULL);
- } else {
- BACK_LOGW("sigaction failed %s", strerror(errno));
- }
+ if (pthread_mutex_lock(&g_sigaction_mutex) < 0) {
+ BACK_LOGW("sigaction failed: %s", strerror(errno));
+ return false;
+ }
+
+ ThreadEntry* entry = ThreadEntry::Get(Pid(), Tid());
+ entry->Lock();
+
+ struct sigaction act, oldact;
+ memset(&act, 0, sizeof(act));
+ act.sa_sigaction = SignalHandler;
+ act.sa_flags = SA_RESTART | SA_SIGINFO | SA_ONSTACK;
+ sigemptyset(&act.sa_mask);
+ if (sigaction(THREAD_SIGNAL, &act, &oldact) != 0) {
+ BACK_LOGW("sigaction failed %s", strerror(errno));
+ entry->Unlock();
+ ThreadEntry::Remove(entry);
pthread_mutex_unlock(&g_sigaction_mutex);
- } else {
- BACK_LOGW("unable to acquire sigaction mutex.");
+ return false;
}
- if (retval) {
- FinishUnwind();
+ if (tgkill(Pid(), Tid(), THREAD_SIGNAL) != 0) {
+ BACK_LOGW("tgkill %d failed: %s", Tid(), strerror(errno));
+ sigaction(THREAD_SIGNAL, &oldact, NULL);
+ entry->Unlock();
+ ThreadEntry::Remove(entry);
+ pthread_mutex_unlock(&g_sigaction_mutex);
+ return false;
}
- delete entry;
- return retval;
+ // Wait for the thread to get the ucontext.
+ entry->Wait(0);
+
+ // After the thread has received the signal, allow other unwinders to
+ // continue.
+ sigaction(THREAD_SIGNAL, &oldact, NULL);
+ pthread_mutex_unlock(&g_sigaction_mutex);
+
+ bool unwind_done = impl_->Unwind(num_ignore_frames, entry->GetUcontext());
+
+ // Tell the signal handler to exit and release the entry.
+ entry->Wake();
+
+ return unwind_done;
}
diff --git a/libbacktrace/BacktraceThread.h b/libbacktrace/BacktraceThread.h
index 9310a44..a75a807 100644
--- a/libbacktrace/BacktraceThread.h
+++ b/libbacktrace/BacktraceThread.h
@@ -18,18 +18,14 @@
#define _LIBBACKTRACE_BACKTRACE_THREAD_H
#include <inttypes.h>
+#include <pthread.h>
#include <signal.h>
+#include <string.h>
#include <sys/types.h>
+#include <ucontext.h>
#include "BacktraceImpl.h"
-enum state_e {
- STATE_WAITING = 0,
- STATE_DUMPING,
- STATE_DONE,
- STATE_CANCEL,
-};
-
// The signal used to cause a thread to dump the stack.
#if defined(__GLIBC__)
// GLIBC reserves __SIGRTMIN signals, so use SIGRTMIN to avoid errors.
@@ -38,62 +34,57 @@
#define THREAD_SIGNAL (__SIGRTMIN+1)
#endif
-class BacktraceThreadInterface;
+class ThreadEntry {
+public:
+ static ThreadEntry* Get(pid_t pid, pid_t tid, bool create = true);
-struct ThreadEntry {
- ThreadEntry(
- BacktraceThreadInterface* impl, pid_t pid, pid_t tid,
- size_t num_ignore_frames);
+ static void Remove(ThreadEntry* entry);
+
+ inline void CopyUcontext(ucontext_t* ucontext) {
+ memcpy(&ucontext_, ucontext, sizeof(ucontext_));
+ }
+
+ void Wake();
+
+ void Wait(int);
+
+ inline void Lock() {
+ pthread_mutex_lock(&mutex_);
+ // Reset the futex value in case of multiple unwinds of the same thread.
+ futex_ = 0;
+ }
+
+ inline void Unlock() {
+ pthread_mutex_unlock(&mutex_);
+ }
+
+ inline ucontext_t* GetUcontext() { return &ucontext_; }
+
+private:
+ ThreadEntry(pid_t pid, pid_t tid);
~ThreadEntry();
- bool Match(pid_t chk_pid, pid_t chk_tid) { return (chk_pid == pid && chk_tid == tid); }
+ bool Match(pid_t chk_pid, pid_t chk_tid) { return (chk_pid == pid_ && chk_tid == tid_); }
- static ThreadEntry* AddThreadToUnwind(
- BacktraceThreadInterface* thread_intf, pid_t pid, pid_t tid,
- size_t num_ignored_frames);
+ pid_t pid_;
+ pid_t tid_;
+ int futex_;
+ int ref_count_;
+ pthread_mutex_t mutex_;
+ ThreadEntry* next_;
+ ThreadEntry* prev_;
+ ucontext_t ucontext_;
- BacktraceThreadInterface* thread_intf;
- pid_t pid;
- pid_t tid;
- ThreadEntry* next;
- ThreadEntry* prev;
- int32_t state;
- int num_ignore_frames;
-};
-
-// Interface class that does not contain any local storage, only defines
-// virtual functions to be defined by subclasses.
-class BacktraceThreadInterface {
-public:
- virtual ~BacktraceThreadInterface() { }
-
- virtual void ThreadUnwind(
- siginfo_t* siginfo, void* sigcontext, size_t num_ignore_frames) = 0;
+ static ThreadEntry* list_;
+ static pthread_mutex_t list_mutex_;
};
class BacktraceThread : public BacktraceCurrent {
public:
- // impl and thread_intf should point to the same object, this allows
- // the compiler to catch if an implementation does not properly
- // subclass both.
- BacktraceThread(
- BacktraceImpl* impl, BacktraceThreadInterface* thread_intf, pid_t tid,
- BacktraceMap* map);
+ BacktraceThread(BacktraceImpl* impl, pid_t tid, BacktraceMap* map);
virtual ~BacktraceThread();
- virtual bool Unwind(size_t num_ignore_frames);
-
- virtual void ThreadUnwind(
- siginfo_t* siginfo, void* sigcontext, size_t num_ignore_frames) {
- thread_intf_->ThreadUnwind(siginfo, sigcontext, num_ignore_frames);
- }
-
-private:
- virtual bool TriggerUnwindOnThread(ThreadEntry* entry);
-
- virtual void FinishUnwind();
-
- BacktraceThreadInterface* thread_intf_;
+ virtual bool Unwind(size_t num_ignore_frames, ucontext_t* ucontext);
};
#endif // _LIBBACKTRACE_BACKTRACE_THREAD_H
diff --git a/libbacktrace/UnwindCurrent.cpp b/libbacktrace/UnwindCurrent.cpp
index 67d372a..e5f7c3d 100755
--- a/libbacktrace/UnwindCurrent.cpp
+++ b/libbacktrace/UnwindCurrent.cpp
@@ -24,6 +24,7 @@
#include <libunwind.h>
#include "BacktraceLog.h"
+#include "BacktraceThread.h"
#include "UnwindCurrent.h"
#include "UnwindMap.h"
@@ -36,15 +37,45 @@
UnwindCurrent::~UnwindCurrent() {
}
-bool UnwindCurrent::Unwind(size_t num_ignore_frames) {
- int ret = unw_getcontext(&context_);
- if (ret < 0) {
- BACK_LOGW("unw_getcontext failed %d", ret);
- return false;
+bool UnwindCurrent::Unwind(size_t num_ignore_frames, ucontext_t* ucontext) {
+ if (!ucontext) {
+ int ret = unw_getcontext(&context_);
+ if (ret < 0) {
+ BACK_LOGW("unw_getcontext failed %d", ret);
+ return false;
+ }
+ }
+ else {
+ GetUnwContextFromUcontext(ucontext);
}
return UnwindFromContext(num_ignore_frames, false);
}
+void UnwindCurrent::GetUnwContextFromUcontext(const ucontext_t* ucontext) {
+ unw_tdep_context_t* unw_context = reinterpret_cast<unw_tdep_context_t*>(&context_);
+
+#if defined(__arm__)
+ unw_context->regs[0] = ucontext->uc_mcontext.arm_r0;
+ unw_context->regs[1] = ucontext->uc_mcontext.arm_r1;
+ unw_context->regs[2] = ucontext->uc_mcontext.arm_r2;
+ unw_context->regs[3] = ucontext->uc_mcontext.arm_r3;
+ unw_context->regs[4] = ucontext->uc_mcontext.arm_r4;
+ unw_context->regs[5] = ucontext->uc_mcontext.arm_r5;
+ unw_context->regs[6] = ucontext->uc_mcontext.arm_r6;
+ unw_context->regs[7] = ucontext->uc_mcontext.arm_r7;
+ unw_context->regs[8] = ucontext->uc_mcontext.arm_r8;
+ unw_context->regs[9] = ucontext->uc_mcontext.arm_r9;
+ unw_context->regs[10] = ucontext->uc_mcontext.arm_r10;
+ unw_context->regs[11] = ucontext->uc_mcontext.arm_fp;
+ unw_context->regs[12] = ucontext->uc_mcontext.arm_ip;
+ unw_context->regs[13] = ucontext->uc_mcontext.arm_sp;
+ unw_context->regs[14] = ucontext->uc_mcontext.arm_lr;
+ unw_context->regs[15] = ucontext->uc_mcontext.arm_pc;
+#else
+ unw_context->uc_mcontext = ucontext->uc_mcontext;
+#endif
+}
+
std::string UnwindCurrent::GetFunctionNameRaw(uintptr_t pc, uintptr_t* offset) {
*offset = 0;
char buf[512];
@@ -122,47 +153,6 @@
return true;
}
-void UnwindCurrent::ExtractContext(void* sigcontext) {
- unw_tdep_context_t* context = reinterpret_cast<unw_tdep_context_t*>(&context_);
- const ucontext_t* uc = reinterpret_cast<const ucontext_t*>(sigcontext);
-
-#if defined(__arm__)
- context->regs[0] = uc->uc_mcontext.arm_r0;
- context->regs[1] = uc->uc_mcontext.arm_r1;
- context->regs[2] = uc->uc_mcontext.arm_r2;
- context->regs[3] = uc->uc_mcontext.arm_r3;
- context->regs[4] = uc->uc_mcontext.arm_r4;
- context->regs[5] = uc->uc_mcontext.arm_r5;
- context->regs[6] = uc->uc_mcontext.arm_r6;
- context->regs[7] = uc->uc_mcontext.arm_r7;
- context->regs[8] = uc->uc_mcontext.arm_r8;
- context->regs[9] = uc->uc_mcontext.arm_r9;
- context->regs[10] = uc->uc_mcontext.arm_r10;
- context->regs[11] = uc->uc_mcontext.arm_fp;
- context->regs[12] = uc->uc_mcontext.arm_ip;
- context->regs[13] = uc->uc_mcontext.arm_sp;
- context->regs[14] = uc->uc_mcontext.arm_lr;
- context->regs[15] = uc->uc_mcontext.arm_pc;
-#else
- context->uc_mcontext = uc->uc_mcontext;
-#endif
-}
-
-//-------------------------------------------------------------------------
-// UnwindThread functions.
-//-------------------------------------------------------------------------
-UnwindThread::UnwindThread() {
-}
-
-UnwindThread::~UnwindThread() {
-}
-
-void UnwindThread::ThreadUnwind(
- siginfo_t* /*siginfo*/, void* sigcontext, size_t num_ignore_frames) {
- ExtractContext(sigcontext);
- UnwindFromContext(num_ignore_frames, true);
-}
-
//-------------------------------------------------------------------------
// C++ object creation function.
//-------------------------------------------------------------------------
@@ -171,6 +161,5 @@
}
Backtrace* CreateThreadObj(pid_t tid, BacktraceMap* map) {
- UnwindThread* thread_obj = new UnwindThread();
- return new BacktraceThread(thread_obj, thread_obj, tid, map);
+ return new BacktraceThread(new UnwindCurrent(), tid, map);
}
diff --git a/libbacktrace/UnwindCurrent.h b/libbacktrace/UnwindCurrent.h
index 41080c7..2375e6e 100644
--- a/libbacktrace/UnwindCurrent.h
+++ b/libbacktrace/UnwindCurrent.h
@@ -20,7 +20,6 @@
#include <string>
#include "BacktraceImpl.h"
-#include "BacktraceThread.h"
#define UNW_LOCAL_ONLY
#include <libunwind.h>
@@ -30,25 +29,16 @@
UnwindCurrent();
virtual ~UnwindCurrent();
- virtual bool Unwind(size_t num_ignore_frames);
+ virtual bool Unwind(size_t num_ignore_frames, ucontext_t* ucontext);
virtual std::string GetFunctionNameRaw(uintptr_t pc, uintptr_t* offset);
bool UnwindFromContext(size_t num_ignore_frames, bool within_handler);
- void ExtractContext(void* sigcontext);
+ void GetUnwContextFromUcontext(const ucontext_t* context);
protected:
unw_context_t context_;
};
-class UnwindThread : public UnwindCurrent, public BacktraceThreadInterface {
-public:
- UnwindThread();
- virtual ~UnwindThread();
-
- virtual void ThreadUnwind(
- siginfo_t* siginfo, void* sigcontext, size_t num_ignore_frames);
-};
-
#endif // _LIBBACKTRACE_UNWIND_CURRENT_H
diff --git a/libbacktrace/UnwindPtrace.cpp b/libbacktrace/UnwindPtrace.cpp
index 5ca7e60..63b4f16 100644
--- a/libbacktrace/UnwindPtrace.cpp
+++ b/libbacktrace/UnwindPtrace.cpp
@@ -45,7 +45,12 @@
}
}
-bool UnwindPtrace::Unwind(size_t num_ignore_frames) {
+bool UnwindPtrace::Unwind(size_t num_ignore_frames, ucontext_t* ucontext) {
+ if (ucontext) {
+ BACK_LOGW("Unwinding from a specified context not supported yet.");
+ return false;
+ }
+
addr_space_ = unw_create_addr_space(&_UPT_accessors, 0);
if (!addr_space_) {
BACK_LOGW("unw_create_addr_space failed.");
diff --git a/libbacktrace/UnwindPtrace.h b/libbacktrace/UnwindPtrace.h
index 1e82117..2fb7967 100644
--- a/libbacktrace/UnwindPtrace.h
+++ b/libbacktrace/UnwindPtrace.h
@@ -28,7 +28,7 @@
UnwindPtrace();
virtual ~UnwindPtrace();
- virtual bool Unwind(size_t num_ignore_frames);
+ virtual bool Unwind(size_t num_ignore_frames, ucontext_t* ucontext);
virtual std::string GetFunctionNameRaw(uintptr_t pc, uintptr_t* offset);
diff --git a/libbacktrace/backtrace_test.cpp b/libbacktrace/backtrace_test.cpp
index 9744922..ed6b211 100644
--- a/libbacktrace/backtrace_test.cpp
+++ b/libbacktrace/backtrace_test.cpp
@@ -615,6 +615,49 @@
}
}
+TEST(libbacktrace, thread_multiple_dump_same_thread) {
+ pthread_attr_t attr;
+ pthread_attr_init(&attr);
+ pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
+ thread_t runner;
+ runner.tid = 0;
+ runner.state = 0;
+ ASSERT_TRUE(pthread_create(&runner.threadId, &attr, ThreadMaxRun, &runner) == 0);
+
+ // Wait for tids to be set.
+ ASSERT_TRUE(WaitForNonZero(&runner.state, 10));
+
+ // Start all of the dumpers at once, they will spin until they are signalled
+ // to begin their dump run.
+ int32_t dump_now = 0;
+ // Dump the same thread NUM_THREADS simultaneously.
+ std::vector<dump_thread_t> dumpers(NUM_THREADS);
+ for (size_t i = 0; i < NUM_THREADS; i++) {
+ dumpers[i].thread.tid = runner.tid;
+ dumpers[i].thread.state = 0;
+ dumpers[i].done = 0;
+ dumpers[i].now = &dump_now;
+
+ ASSERT_TRUE(pthread_create(&dumpers[i].thread.threadId, &attr, ThreadDump, &dumpers[i]) == 0);
+ }
+
+ // Start all of the dumpers going at once.
+ android_atomic_acquire_store(1, &dump_now);
+
+ for (size_t i = 0; i < NUM_THREADS; i++) {
+ ASSERT_TRUE(WaitForNonZero(&dumpers[i].done, 100));
+
+ ASSERT_TRUE(dumpers[i].backtrace != NULL);
+ VerifyMaxDump(dumpers[i].backtrace);
+
+ delete dumpers[i].backtrace;
+ dumpers[i].backtrace = NULL;
+ }
+
+ // Tell the runner thread to exit its infinite loop.
+ android_atomic_acquire_store(0, &runner.state);
+}
+
// This test is for UnwindMaps that should share the same map cursor when
// multiple maps are created for the current process at the same time.
TEST(libbacktrace, simultaneous_maps) {