Mercurial > hg > graal-compiler
view src/os/bsd/dtrace/jvm_dtrace.c @ 6275:957c266d8bc5
Merge with http://hg.openjdk.java.net/hsx/hsx24/hotspot/
author | Doug Simon <doug.simon@oracle.com> |
---|---|
date | Tue, 21 Aug 2012 10:39:19 +0200 |
parents | 436b4a3231bf |
children | e95fc50106cf |
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/* * Copyright (c) 2006, 2010, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #include <door.h> #include <errno.h> #include <fcntl.h> #include <limits.h> #include <poll.h> #include <signal.h> #include <stdarg.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/types.h> #include <sys/stat.h> #include <thread.h> #include <unistd.h> #include "jvm_dtrace.h" // NOTE: These constants are used in JVM code as well. // KEEP JVM CODE IN SYNC if you are going to change these... #define DTRACE_ALLOC_PROBES 0x1 #define DTRACE_METHOD_PROBES 0x2 #define DTRACE_MONITOR_PROBES 0x4 #define DTRACE_ALL_PROBES -1 // generic error messages #define JVM_ERR_OUT_OF_MEMORY "out of memory (native heap)" #define JVM_ERR_INVALID_PARAM "invalid input parameter(s)" #define JVM_ERR_NULL_PARAM "input paramater is NULL" // error messages for attach #define JVM_ERR_CANT_OPEN_DOOR "cannot open door file" #define JVM_ERR_CANT_CREATE_ATTACH_FILE "cannot create attach file" #define JVM_ERR_DOOR_FILE_PERMISSION "door file is not secure" #define JVM_ERR_CANT_SIGNAL "cannot send SIGQUIT to target" // error messages for enable probe #define JVM_ERR_DOOR_CMD_SEND "door command send failed" #define JVM_ERR_DOOR_CANT_READ_STATUS "cannot read door command status" #define JVM_ERR_DOOR_CMD_STATUS "door command error status" // error message for detach #define JVM_ERR_CANT_CLOSE_DOOR "cannot close door file" #define RESTARTABLE(_cmd, _result) do { \ do { \ _result = _cmd; \ } while((_result == -1) && (errno == EINTR)); \ } while(0) struct _jvm_t { pid_t pid; int door_fd; }; static int libjvm_dtrace_debug; static void print_debug(const char* fmt,...) { if (libjvm_dtrace_debug) { va_list alist; va_start(alist, fmt); fputs("libjvm_dtrace DEBUG: ", stderr); vfprintf(stderr, fmt, alist); va_end(alist); } } /* Key for thread local error message */ static thread_key_t jvm_error_key; /* init function for this library */ static void init_jvm_dtrace() { /* check for env. var for debug mode */ libjvm_dtrace_debug = getenv("LIBJVM_DTRACE_DEBUG") != NULL; /* create key for thread local error message */ if (thr_keycreate(&jvm_error_key, NULL) != 0) { print_debug("can't create thread_key_t for jvm error key\n"); // exit(1); ? } } #pragma init(init_jvm_dtrace) /* set thread local error message */ static void set_jvm_error(const char* msg) { thr_setspecific(jvm_error_key, (void*)msg); } /* clear thread local error message */ static void clear_jvm_error() { thr_setspecific(jvm_error_key, NULL); } /* file handling functions that can handle interrupt */ static int file_open(const char* path, int flag) { int ret; RESTARTABLE(open(path, flag), ret); return ret; } static int file_close(int fd) { int ret; RESTARTABLE(close(fd), ret); return ret; } static int file_read(int fd, char* buf, int len) { int ret; RESTARTABLE(read(fd, buf, len), ret); return ret; } /* send SIGQUIT signal to given process */ static int send_sigquit(pid_t pid) { int ret; RESTARTABLE(kill(pid, SIGQUIT), ret); return ret; } /* called to check permissions on attach file */ static int check_permission(const char* path) { struct stat64 sb; uid_t uid, gid; int res; /* * Check that the path is owned by the effective uid/gid of this * process. Also check that group/other access is not allowed. */ uid = geteuid(); gid = getegid(); res = stat64(path, &sb); if (res != 0) { print_debug("stat failed for %s\n", path); return -1; } if ((sb.st_uid != uid) || (sb.st_gid != gid) || ((sb.st_mode & (S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH)) != 0)) { print_debug("well-known file %s is not secure\n", path); return -1; } return 0; } #define ATTACH_FILE_PATTERN "/tmp/.attach_pid%d" /* fill-in the name of attach file name in given buffer */ static void fill_attach_file_name(char* path, int len, pid_t pid) { memset(path, 0, len); sprintf(path, ATTACH_FILE_PATTERN, pid); } #define DOOR_FILE_PATTERN "/tmp/.java_pid%d" /* open door file for the given JVM */ static int open_door(pid_t pid) { char path[PATH_MAX + 1]; int fd; sprintf(path, DOOR_FILE_PATTERN, pid); fd = file_open(path, O_RDONLY); if (fd < 0) { set_jvm_error(JVM_ERR_CANT_OPEN_DOOR); print_debug("cannot open door file %s\n", path); return -1; } print_debug("opened door file %s\n", path); if (check_permission(path) != 0) { set_jvm_error(JVM_ERR_DOOR_FILE_PERMISSION); print_debug("check permission failed for %s\n", path); file_close(fd); fd = -1; } return fd; } /* create attach file for given process */ static int create_attach_file(pid_t pid) { char path[PATH_MAX + 1]; int fd; fill_attach_file_name(path, sizeof(path), pid); fd = file_open(path, O_CREAT | O_RDWR); if (fd < 0) { set_jvm_error(JVM_ERR_CANT_CREATE_ATTACH_FILE); print_debug("cannot create file %s\n", path); } else { print_debug("created attach file %s\n", path); } return fd; } /* delete attach file for given process */ static void delete_attach_file(pid_t pid) { char path[PATH_MAX + 1]; fill_attach_file_name(path, sizeof(path), pid); int res = unlink(path); if (res) { print_debug("cannot delete attach file %s\n", path); } else { print_debug("deleted attach file %s\n", path); } } /* attach to given JVM */ jvm_t* jvm_attach(pid_t pid) { jvm_t* jvm; int door_fd, attach_fd, i; jvm = (jvm_t*) calloc(1, sizeof(jvm_t)); if (jvm == NULL) { set_jvm_error(JVM_ERR_OUT_OF_MEMORY); print_debug("calloc failed in %s at %d\n", __FILE__, __LINE__); return NULL; } jvm->pid = pid; attach_fd = -1; door_fd = open_door(pid); if (door_fd < 0) { print_debug("trying to create attach file\n"); if ((attach_fd = create_attach_file(pid)) < 0) { goto quit; } /* send QUIT signal to the target so that it will * check for the attach file. */ if (send_sigquit(pid) != 0) { set_jvm_error(JVM_ERR_CANT_SIGNAL); print_debug("sending SIGQUIT failed\n"); goto quit; } /* give the target VM time to start the attach mechanism */ do { int res; RESTARTABLE(poll(0, 0, 200), res); door_fd = open_door(pid); i++; } while (i <= 50 && door_fd == -1); if (door_fd < 0) { print_debug("Unable to open door to process %d\n", pid); goto quit; } } quit: if (attach_fd >= 0) { file_close(attach_fd); delete_attach_file(jvm->pid); } if (door_fd >= 0) { jvm->door_fd = door_fd; clear_jvm_error(); } else { free(jvm); jvm = NULL; } return jvm; } /* return the last thread local error message */ const char* jvm_get_last_error() { const char* res = NULL; thr_getspecific(jvm_error_key, (void**)&res); return res; } /* detach the givenb JVM */ int jvm_detach(jvm_t* jvm) { if (jvm) { int res; if (jvm->door_fd != -1) { if (file_close(jvm->door_fd) != 0) { set_jvm_error(JVM_ERR_CANT_CLOSE_DOOR); res = -1; } else { clear_jvm_error(); res = 0; } } free(jvm); return res; } else { set_jvm_error(JVM_ERR_NULL_PARAM); print_debug("jvm_t* is NULL\n"); return -1; } } /* * A simple table to translate some known errors into reasonable * error messages */ static struct { int err; const char* msg; } const error_messages[] = { { 100, "Bad request" }, { 101, "Protocol mismatch" }, { 102, "Resource failure" }, { 103, "Internal error" }, { 104, "Permission denied" }, }; /* * Lookup the given error code and return the appropriate * message. If not found return NULL. */ static const char* translate_error(int err) { int table_size = sizeof(error_messages) / sizeof(error_messages[0]); int i; for (i=0; i<table_size; i++) { if (err == error_messages[i].err) { return error_messages[i].msg; } } return NULL; } /* * Current protocol version */ static const char* PROTOCOL_VERSION = "1"; #define RES_BUF_SIZE 128 /* * Enqueue attach-on-demand command to the given JVM */ static int enqueue_command(jvm_t* jvm, const char* cstr, int arg_count, const char** args) { size_t size; door_arg_t door_args; char res_buffer[RES_BUF_SIZE]; int rc, i; char* buf = NULL; int result = -1; /* * First we get the command string and create the start of the * argument string to send to the target VM: * <ver>\0<cmd>\0 */ if (cstr == NULL) { print_debug("command name is NULL\n"); goto quit; } size = strlen(PROTOCOL_VERSION) + strlen(cstr) + 2; buf = (char*)malloc(size); if (buf != NULL) { char* pos = buf; strcpy(buf, PROTOCOL_VERSION); pos += strlen(PROTOCOL_VERSION)+1; strcpy(pos, cstr); } else { set_jvm_error(JVM_ERR_OUT_OF_MEMORY); print_debug("malloc failed at %d in %s\n", __LINE__, __FILE__); goto quit; } /* * Next we iterate over the arguments and extend the buffer * to include them. */ for (i=0; i<arg_count; i++) { cstr = args[i]; if (cstr != NULL) { size_t len = strlen(cstr); char* newbuf = (char*)realloc(buf, size+len+1); if (newbuf == NULL) { set_jvm_error(JVM_ERR_OUT_OF_MEMORY); print_debug("realloc failed in %s at %d\n", __FILE__, __LINE__); goto quit; } buf = newbuf; strcpy(buf+size, cstr); size += len+1; } } /* * The arguments to the door function are in 'buf' so we now * do the door call */ door_args.data_ptr = buf; door_args.data_size = size; door_args.desc_ptr = NULL; door_args.desc_num = 0; door_args.rbuf = (char*)&res_buffer; door_args.rsize = sizeof(res_buffer); RESTARTABLE(door_call(jvm->door_fd, &door_args), rc); /* * door_call failed */ if (rc == -1) { print_debug("door_call failed\n"); } else { /* * door_call succeeded but the call didn't return the the expected jint. */ if (door_args.data_size < sizeof(int)) { print_debug("Enqueue error - reason unknown as result is truncated!"); } else { int* res = (int*)(door_args.data_ptr); if (*res != 0) { const char* msg = translate_error(*res); if (msg == NULL) { print_debug("Unable to enqueue command to target VM: %d\n", *res); } else { print_debug("Unable to enqueue command to target VM: %s\n", msg); } } else { /* * The door call should return a file descriptor to one end of * a socket pair */ if ((door_args.desc_ptr != NULL) && (door_args.desc_num == 1) && (door_args.desc_ptr->d_attributes & DOOR_DESCRIPTOR)) { result = door_args.desc_ptr->d_data.d_desc.d_descriptor; } else { print_debug("Reply from enqueue missing descriptor!\n"); } } } } quit: if (buf) free(buf); return result; } /* read status code for a door command */ static int read_status(int fd) { char ch, buf[16]; int index = 0; while (1) { if (file_read(fd, &ch, sizeof(ch)) != sizeof(ch)) { set_jvm_error(JVM_ERR_DOOR_CANT_READ_STATUS); print_debug("door cmd status: read status failed\n"); return -1; } buf[index++] = ch; if (ch == '\n') { buf[index - 1] = '\0'; return atoi(buf); } if (index == sizeof(buf)) { set_jvm_error(JVM_ERR_DOOR_CANT_READ_STATUS); print_debug("door cmd status: read status overflow\n"); return -1; } } } static const char* ENABLE_DPROBES_CMD = "enabledprobes"; /* enable one or more DTrace probes for a given JVM */ int jvm_enable_dtprobes(jvm_t* jvm, int num_probe_types, const char** probe_types) { int fd, status = 0; char ch; const char* args[1]; char buf[16]; int probe_type = 0, index; int count = 0; if (jvm == NULL) { set_jvm_error(JVM_ERR_NULL_PARAM); print_debug("jvm_t* is NULL\n"); return -1; } if (num_probe_types == 0 || probe_types == NULL || probe_types[0] == NULL) { set_jvm_error(JVM_ERR_INVALID_PARAM); print_debug("invalid probe type argument(s)\n"); return -1; } for (index = 0; index < num_probe_types; index++) { const char* p = probe_types[index]; if (strcmp(p, JVM_DTPROBE_OBJECT_ALLOC) == 0) { probe_type |= DTRACE_ALLOC_PROBES; count++; } else if (strcmp(p, JVM_DTPROBE_METHOD_ENTRY) == 0 || strcmp(p, JVM_DTPROBE_METHOD_RETURN) == 0) { probe_type |= DTRACE_METHOD_PROBES; count++; } else if (strcmp(p, JVM_DTPROBE_MONITOR_ENTER) == 0 || strcmp(p, JVM_DTPROBE_MONITOR_ENTERED) == 0 || strcmp(p, JVM_DTPROBE_MONITOR_EXIT) == 0 || strcmp(p, JVM_DTPROBE_MONITOR_WAIT) == 0 || strcmp(p, JVM_DTPROBE_MONITOR_WAITED) == 0 || strcmp(p, JVM_DTPROBE_MONITOR_NOTIFY) == 0 || strcmp(p, JVM_DTPROBE_MONITOR_NOTIFYALL) == 0) { probe_type |= DTRACE_MONITOR_PROBES; count++; } else if (strcmp(p, JVM_DTPROBE_ALL) == 0) { probe_type |= DTRACE_ALL_PROBES; count++; } } if (count == 0) { return count; } sprintf(buf, "%d", probe_type); args[0] = buf; fd = enqueue_command(jvm, ENABLE_DPROBES_CMD, 1, args); if (fd < 0) { set_jvm_error(JVM_ERR_DOOR_CMD_SEND); return -1; } status = read_status(fd); // non-zero status is error if (status) { set_jvm_error(JVM_ERR_DOOR_CMD_STATUS); print_debug("%s command failed (status: %d) in target JVM\n", ENABLE_DPROBES_CMD, status); file_close(fd); return -1; } // read from stream until EOF while (file_read(fd, &ch, sizeof(ch)) == sizeof(ch)) { if (libjvm_dtrace_debug) { printf("%c", ch); } } file_close(fd); clear_jvm_error(); return count; }