Rearrange the code (put the server on top) so that the server imports only the
modules it requires. This reduces the startup time of child processes.
Signed-off-by: Michael Goldish <mgoldish@xxxxxxxxxx>
---
client/tests/kvm/kvm_subprocess.py | 359 ++++++++++++++++++------------------
1 files changed, 181 insertions(+), 178 deletions(-)
diff --git a/client/tests/kvm/kvm_subprocess.py b/client/tests/kvm/kvm_subprocess.py
index f748586..424c801 100755
--- a/client/tests/kvm/kvm_subprocess.py
+++ b/client/tests/kvm/kvm_subprocess.py
@@ -5,8 +5,187 @@ A class and functions used for running and controlling child processes.
@copyright: 2008-2009 Red Hat Inc.
"""
-import sys, subprocess, pty, select, os, time, signal, re, termios, fcntl
-import threading, logging, commands
+import os, sys, pty, select, termios, fcntl
+
+
+# The following helper functions are shared by the server and the client.
+
+def _lock(filename):
+ if not os.path.exists(filename):
+ open(filename, "w").close()
+ fd = os.open(filename, os.O_RDWR)
+ fcntl.lockf(fd, fcntl.LOCK_EX)
+ return fd
+
+
+def _unlock(fd):
+ fcntl.lockf(fd, fcntl.LOCK_UN)
+ os.close(fd)
+
+
+def _locked(filename):
+ try:
+ fd = os.open(filename, os.O_RDWR)
+ except:
+ return False
+ try:
+ fcntl.lockf(fd, fcntl.LOCK_EX | fcntl.LOCK_NB)
+ except:
+ os.close(fd)
+ return True
+ fcntl.lockf(fd, fcntl.LOCK_UN)
+ os.close(fd)
+ return False
+
+
+def _wait(filename):
+ fd = _lock(filename)
+ _unlock(fd)
+
+
+def _get_filenames(base_dir, id):
+ return [os.path.join(base_dir, s + id) for s in
+ "shell-pid-", "status-", "output-", "inpipe-",
+ "lock-server-running-", "lock-client-starting-"]
+
+
+def _get_reader_filename(base_dir, id, reader):
+ return os.path.join(base_dir, "outpipe-%s-%s" % (reader, id))
+
+
+# The following is the server part of the module.
+
+if __name__ == "__main__":
+ id = sys.stdin.readline().strip()
+ echo = sys.stdin.readline().strip() == "True"
+ readers = sys.stdin.readline().strip().split(",")
+ command = sys.stdin.readline().strip() + " && echo %s > /dev/null" % id
+
+ # Define filenames to be used for communication
+ base_dir = "/tmp/kvm_spawn"
+ (shell_pid_filename,
+ status_filename,
+ output_filename,
+ inpipe_filename,
+ lock_server_running_filename,
+ lock_client_starting_filename) = _get_filenames(base_dir, id)
+
+ # Populate the reader filenames list
+ reader_filenames = [_get_reader_filename(base_dir, id, reader)
+ for reader in readers]
+
+ # Set $TERM = dumb
+ os.putenv("TERM", "dumb")
+
+ (shell_pid, shell_fd) = pty.fork()
+ if shell_pid == 0:
+ # Child process: run the command in a subshell
+ os.execv("/bin/sh", ["/bin/sh", "-c", command])
+ else:
+ # Parent process
+ lock_server_running = _lock(lock_server_running_filename)
+
+ # Set terminal echo on/off and disable pre- and post-processing
+ attr = termios.tcgetattr(shell_fd)
+ attr[0] &= ~termios.INLCR
+ attr[0] &= ~termios.ICRNL
+ attr[0] &= ~termios.IGNCR
+ attr[1] &= ~termios.OPOST
+ if echo:
+ attr[3] |= termios.ECHO
+ else:
+ attr[3] &= ~termios.ECHO
+ termios.tcsetattr(shell_fd, termios.TCSANOW, attr)
+
+ # Open output file
+ output_file = open(output_filename, "w")
+ # Open input pipe
+ os.mkfifo(inpipe_filename)
+ inpipe_fd = os.open(inpipe_filename, os.O_RDWR)
+ # Open output pipes (readers)
+ reader_fds = []
+ for filename in reader_filenames:
+ os.mkfifo(filename)
+ reader_fds.append(os.open(filename, os.O_RDWR))
+
+ # Write shell PID to file
+ file = open(shell_pid_filename, "w")
+ file.write(str(shell_pid))
+ file.close()
+
+ # Print something to stdout so the client can start working
+ print "Server %s ready" % id
+ sys.stdout.flush()
+
+ # Initialize buffers
+ buffers = ["" for reader in readers]
+
+ # Read from child and write to files/pipes
+ while True:
+ check_termination = False
+ # Make a list of reader pipes whose buffers are not empty
+ fds = [fd for (i, fd) in enumerate(reader_fds) if buffers[i]]
+ # Wait until there's something to do
+ r, w, x = select.select([shell_fd, inpipe_fd], fds, [], 0.5)
+ # If a reader pipe is ready for writing --
+ for (i, fd) in enumerate(reader_fds):
+ if fd in w:
+ bytes_written = os.write(fd, buffers[i])
+ buffers[i] = buffers[i][bytes_written:]
+ # If there's data to read from the child process --
+ if shell_fd in r:
+ try:
+ data = os.read(shell_fd, 16384)
+ except OSError:
+ data = ""
+ if not data:
+ check_termination = True
+ # Remove carriage returns from the data -- they often cause
+ # trouble and are normally not needed
+ data = data.replace("\r", "")
+ output_file.write(data)
+ output_file.flush()
+ for i in range(len(readers)):
+ buffers[i] += data
+ # If os.read() raised an exception or there was nothing to read --
+ if check_termination or shell_fd not in r:
+ pid, status = os.waitpid(shell_pid, os.WNOHANG)
+ if pid:
+ status = os.WEXITSTATUS(status)
+ break
+ # If there's data to read from the client --
+ if inpipe_fd in r:
+ data = os.read(inpipe_fd, 1024)
+ os.write(shell_fd, data)
+
+ # Write the exit status to a file
+ file = open(status_filename, "w")
+ file.write(str(status))
+ file.close()
+
+ # Wait for the client to finish initializing
+ _wait(lock_client_starting_filename)
+
+ # Delete FIFOs
+ for filename in reader_filenames + [inpipe_filename]:
+ try:
+ os.unlink(filename)
+ except OSError:
+ pass
+
+ # Close all files and pipes
+ output_file.close()
+ os.close(inpipe_fd)
+ for fd in reader_fds:
+ os.close(fd)
+
+ _unlock(lock_server_running)
+ exit(0)
+
+
+# The following is the client part of the module.
+
+import subprocess, time, signal, re, threading, logging
import common, kvm_utils
@@ -77,49 +256,6 @@ def run_fg(command, output_func=None, output_prefix="", timeout=1.0):
return (status, output)
-def _lock(filename):
- if not os.path.exists(filename):
- open(filename, "w").close()
- fd = os.open(filename, os.O_RDWR)
- fcntl.lockf(fd, fcntl.LOCK_EX)
- return fd
-
-
-def _unlock(fd):
- fcntl.lockf(fd, fcntl.LOCK_UN)
- os.close(fd)
-
-
-def _locked(filename):
- try:
- fd = os.open(filename, os.O_RDWR)
- except:
- return False
- try:
- fcntl.lockf(fd, fcntl.LOCK_EX | fcntl.LOCK_NB)
- except:
- os.close(fd)
- return True
- fcntl.lockf(fd, fcntl.LOCK_UN)
- os.close(fd)
- return False
-
-
-def _wait(filename):
- fd = _lock(filename)
- _unlock(fd)
-
-
-def _get_filenames(base_dir, id):
- return [os.path.join(base_dir, s + id) for s in
- "shell-pid-", "status-", "output-", "inpipe-",
- "lock-server-running-", "lock-client-starting-"]
-
-
-def _get_reader_filename(base_dir, id, reader):
- return os.path.join(base_dir, "outpipe-%s-%s" % (reader, id))
-
-
class kvm_spawn:
"""
This class is used for spawning and controlling a child process.
@@ -1031,136 +1167,3 @@ class kvm_shell_session(kvm_expect):
internal_timeout,
print_func)
return output
-
-
-# The following is the server part of the module.
-
-def _server_main():
- id = sys.stdin.readline().strip()
- echo = sys.stdin.readline().strip() == "True"
- readers = sys.stdin.readline().strip().split(",")
- command = sys.stdin.readline().strip() + " && echo %s > /dev/null" % id
-
- # Define filenames to be used for communication
- base_dir = "/tmp/kvm_spawn"
- (shell_pid_filename,
- status_filename,
- output_filename,
- inpipe_filename,
- lock_server_running_filename,
- lock_client_starting_filename) = _get_filenames(base_dir, id)
-
- # Populate the reader filenames list
- reader_filenames = [_get_reader_filename(base_dir, id, reader)
- for reader in readers]
-
- # Set $TERM = dumb
- os.putenv("TERM", "dumb")
-
- (shell_pid, shell_fd) = pty.fork()
- if shell_pid == 0:
- # Child process: run the command in a subshell
- os.execv("/bin/sh", ["/bin/sh", "-c", command])
- else:
- # Parent process
- lock_server_running = _lock(lock_server_running_filename)
-
- # Set terminal echo on/off and disable pre- and post-processing
- attr = termios.tcgetattr(shell_fd)
- attr[0] &= ~termios.INLCR
- attr[0] &= ~termios.ICRNL
- attr[0] &= ~termios.IGNCR
- attr[1] &= ~termios.OPOST
- if echo:
- attr[3] |= termios.ECHO
- else:
- attr[3] &= ~termios.ECHO
- termios.tcsetattr(shell_fd, termios.TCSANOW, attr)
-
- # Open output file
- output_file = open(output_filename, "w")
- # Open input pipe
- os.mkfifo(inpipe_filename)
- inpipe_fd = os.open(inpipe_filename, os.O_RDWR)
- # Open output pipes (readers)
- reader_fds = []
- for filename in reader_filenames:
- os.mkfifo(filename)
- reader_fds.append(os.open(filename, os.O_RDWR))
-
- # Write shell PID to file
- file = open(shell_pid_filename, "w")
- file.write(str(shell_pid))
- file.close()
-
- # Print something to stdout so the client can start working
- print "Server %s ready" % id
- sys.stdout.flush()
-
- # Initialize buffers
- buffers = ["" for reader in readers]
-
- # Read from child and write to files/pipes
- while True:
- check_termination = False
- # Make a list of reader pipes whose buffers are not empty
- fds = [fd for (i, fd) in enumerate(reader_fds) if buffers[i]]
- # Wait until there's something to do
- r, w, x = select.select([shell_fd, inpipe_fd], fds, [], 0.5)
- # If a reader pipe is ready for writing --
- for (i, fd) in enumerate(reader_fds):
- if fd in w:
- bytes_written = os.write(fd, buffers[i])
- buffers[i] = buffers[i][bytes_written:]
- # If there's data to read from the child process --
- if shell_fd in r:
- try:
- data = os.read(shell_fd, 16384)
- except OSError:
- data = ""
- if not data:
- check_termination = True
- # Remove carriage returns from the data -- they often cause
- # trouble and are normally not needed
- data = data.replace("\r", "")
- output_file.write(data)
- output_file.flush()
- for i in range(len(readers)):
- buffers[i] += data
- # If os.read() raised an exception or there was nothing to read --
- if check_termination or shell_fd not in r:
- pid, status = os.waitpid(shell_pid, os.WNOHANG)
- if pid:
- status = os.WEXITSTATUS(status)
- break
- # If there's data to read from the client --
- if inpipe_fd in r:
- data = os.read(inpipe_fd, 1024)
- os.write(shell_fd, data)
-
- # Write the exit status to a file
- file = open(status_filename, "w")
- file.write(str(status))
- file.close()
-
- # Wait for the client to finish initializing
- _wait(lock_client_starting_filename)
-
- # Delete FIFOs
- for filename in reader_filenames + [inpipe_filename]:
- try:
- os.unlink(filename)
- except OSError:
- pass
-
- # Close all files and pipes
- output_file.close()
- os.close(inpipe_fd)
- for fd in reader_fds:
- os.close(fd)
-
- _unlock(lock_server_running)
-
-
-if __name__ == "__main__":
- _server_main()
--
1.5.4.1
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