Hotfixes

src/common/capio/shm.hpp

@@ -25,7 +25,7 @@
 
 #define SHM_CREATE_CHECK(condition, source)                                                        \
     if (condition) {                                                                               \
-        ERR_EXIT("Unable to open shm: %s", source);                                                \
+        ERR_EXIT("Unable to open shm: %s: %s", source, strerror(errno));                           \
     };
 
 #else
@@ -42,7 +42,7 @@
         LOG("error while creating %s", source);                                                    \
         std::cout << CAPIO_SERVER_CLI_LOG_SERVER_ERROR << " [ " << node_name << " ] "              \
                   << "Unable to create shm: " << source << std::endl;                              \
-        ERR_EXIT("Unable to open shm: %s", source);                                                \
+        ERR_EXIT("Unable to open shm %s: %s", source, strerror(errno));                            \
     };
 
 #endif
@@ -133,7 +133,12 @@ void *get_shm(const std::string &shm_name) {
     }
     void *p = mmap(nullptr, sb.st_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
     if (p == MAP_FAILED) {
-        ERR_EXIT("mmap get_shm %s", shm_name.c_str());
+        LOG("ERROR MMAP arg dump:");
+        LOG("mmap-size:  %ld", sb.st_size);
+        LOG("mmap-prot:  %ld", PROT_READ | PROT_WRITE);
+        LOG("mmap-flags: %ld", MAP_SHARED);
+        LOG("mmap-fd:    %ld", fd);
+        ERR_EXIT("ERROR: mmap failed at get_shm(%s): %s", shm_name.c_str(), strerror(errno));
     }
     if (close(fd) == -1) {
         ERR_EXIT("close");
@@ -151,7 +156,7 @@ void *get_shm_if_exist(const std::string &shm_name) {
         if (errno == ENOENT) {
             return nullptr;
         }
-        ERR_EXIT("get_shm shm_open %s", shm_name.c_str());
+        ERR_EXIT("ERROR: unable to open shared memory %s: %s", shm_name.c_str(), strerror(errno));
     }
     /* Open existing object */
     /* Use shared memory object size as length argument for mmap()
@@ -161,7 +166,13 @@ void *get_shm_if_exist(const std::string &shm_name) {
     }
     void *p = mmap(nullptr, sb.st_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
     if (p == MAP_FAILED) {
-        ERR_EXIT("mmap get_shm %s", shm_name.c_str());
+        LOG("ERROR MMAP arg dump:");
+        LOG("mmap-size:  %ld", sb.st_size);
+        LOG("mmap-prot:  %ld", PROT_READ | PROT_WRITE);
+        LOG("mmap-flags: %ld", MAP_SHARED);
+        LOG("mmap-fd:    %ld", fd);
+        ERR_EXIT("ERROR: mmap failed at get_shm_if_exist(%s): %s", shm_name.c_str(),
+                 strerror(errno));
     }
     if (close(fd) == -1) {
         ERR_EXIT("close");

src/posix/utils/clone.hpp

@@ -18,13 +18,17 @@ inline bool is_capio_tid(const pid_t tid) {
 }
 
 inline void register_capio_tid(const pid_t tid) {
+    START_LOG(syscall_no_intercept(SYS_gettid), "call(tid=%ld)", tid);
     const std::lock_guard<std::mutex> lg(clone_mutex);
     tids->insert(tid);
 }
 
 inline void remove_capio_tid(const pid_t tid) {
+    START_LOG(syscall_no_intercept(SYS_gettid), "call(tid=%ld)", tid);
     const std::lock_guard<std::mutex> lg(clone_mutex);
-    tids->erase(tid);
+    if (tids->find(tid) != tids->end()) {
+        tids->erase(tid);
+    }
 }
 
 inline void init_threading_support() { tids = new std::unordered_set<pid_t>{}; }
@@ -59,6 +63,21 @@ inline void hook_clone_child() {
 
 #ifdef __CAPIO_POSIX
     syscall_no_intercept_flag = true;
+
+    /*
+     * This piece of code is aimed at addressing issues with applications that spawn several
+     * thousand threads that only do computations. When this occurs, under some circumstances CAPIO
+     * might fail to allocate shared memory objects. As such, if child threads ONLY do computation,
+     * we can safely ignore them with CAPIO.
+     */
+    thread_local char *skip_child = std::getenv("CAPIO_IGNORE_CHILD_THREADS");
+    if (skip_child != nullptr) {
+        auto skip_child_str = std::string(skip_child);
+        if (skip_child_str == "ON" || skip_child_str == "TRUE" || skip_child_str == "YES") {
+            return;
+        }
+    }
+
 #endif
     std::unique_lock<std::mutex> lock(clone_mutex);
     clone_cv.wait(lock, [&tid] { return tids->find(tid) != tids->end(); });