Sapan's changes to address cgroups location
[lxc-userspace.git] / lxcsu
diff --git a/lxcsu b/lxcsu
index 3c63f74..11f1cce 100755 (executable)
--- a/lxcsu
+++ b/lxcsu
@@ -3,6 +3,7 @@
 import sys
 import os
 import setns
+import pdb
 
 from argparse import ArgumentParser
 
@@ -11,6 +12,129 @@ drop_capabilities='cap_sys_admin,cap_sys_boot,cap_sys_module'
 # can set to True here, but also use the -d option
 debug = False
 
+#################### should go into a separate libvirtsystemd.py
+# but we want to keep packaging simple for now
+
+# reproducing libvirt's systemd-oriented escaping mechanism
+# http://code.metager.de/source/xref/lib/virt/src/util/virsystemd.c
+# (see original code at the end of this file)
+
+def virSystemdEscapeName (name):
+    result=''
+    def ESCAPE(c,s):
+        # replace hex's output '0x..' into '\x..' 
+        return s+hex(ord(c)).replace('0','\\',1)
+    VALID_CHARS = \
+        "0123456789" + \
+        "abcdefghijklmnopqrstuvwxyz" + \
+        "ABCDEFGHIJKLMNOPQRSTUVWXYZ" + \
+        ":-_.\\"
+    for c in name:
+        if c=='/': 
+            result += '-'
+        elif c in '-\\' or c not in VALID_CHARS:
+            result=ESCAPE(c,result)
+        else:
+            result += c
+    return result
+
+#35static void virSystemdEscapeName(virBufferPtr buf,
+#36                                 const char *name)
+#37{
+#38    static const char hextable[16] = "0123456789abcdef";
+#39
+#40#define ESCAPE(c)                                                       \
+#41    do {                                                                \
+#42        virBufferAddChar(buf, '\\');                                    \
+#43        virBufferAddChar(buf, 'x');                                     \
+#44        virBufferAddChar(buf, hextable[(c >> 4) & 15]);                 \
+#45        virBufferAddChar(buf, hextable[c & 15]);                        \
+#46    } while (0)
+#47
+#48#define VALID_CHARS                             \
+#49        "0123456789"                            \
+#50        "abcdefghijklmnopqrstuvwxyz"            \
+#51        "ABCDEFGHIJKLMNOPQRSTUVWXYZ"            \
+#52        ":-_.\\"
+#53
+#54    if (*name == '.') {
+#55        ESCAPE(*name);
+#56        name++;
+#57    }
+#58
+#59    while (*name) {
+#60        if (*name == '/')
+#61            virBufferAddChar(buf, '-');
+#62        else if (*name == '-' ||
+#63                 *name == '\\' ||
+#64                 !strchr(VALID_CHARS, *name))
+#65            ESCAPE(*name);
+#66        else
+#67            virBufferAddChar(buf, *name);
+#68        name++;
+#69    }
+#70
+#71#undef ESCAPE
+#72#undef VALID_CHARS
+#73}
+
+def virSystemdMakeScopeName (name, drivername, partition):
+    result=''
+    result += virSystemdEscapeName (partition)
+    result += '-'
+    result += virSystemdEscapeName (drivername)
+    result += '\\x2d'
+    result += virSystemdEscapeName (name)
+    result += '.scope'
+    return result
+
+#76char *virSystemdMakeScopeName(const char *name,
+#77                              const char *drivername,
+#78                              const char *partition)
+#79{
+#80    virBuffer buf = VIR_BUFFER_INITIALIZER;
+#81
+#82    if (*partition == '/')
+#83        partition++;
+#84
+#85    virSystemdEscapeName(&buf, partition);
+#86    virBufferAddChar(&buf, '-');
+#87    virSystemdEscapeName(&buf, drivername);
+#88    virBufferAddLit(&buf, "\\x2d");
+#89    virSystemdEscapeName(&buf, name);
+#90    virBufferAddLit(&buf, ".scope");
+#91
+#92    if (virBufferError(&buf)) {
+#93        virReportOOMError();
+#94        return NULL;
+#95    }
+#96
+#97    return virBufferContentAndReset(&buf);
+#98}
+
+### our own additions
+import os.path
+def find_first_dir (candidates):
+    for candidate in candidates:
+        if os.path.isdir(candidate): return candidate
+    raise Exception,"Cannot find valid dir among %s"%'\n'.join(candidates)
+
+def find_sysfs_scope (subsystem, slice_name):
+    subsystem1=subsystem
+    subsystem2=subsystem
+    if subsystem=='cpuacct':
+        subsystem2='cpu,cpuacct'
+    candidates = [ 
+        # for f16 and our locally brewed libvirt 1.0.4
+        "/sys/fs/cgroup/%s/libvirt/lxc/%s"%(subsystem1, slice_name),
+        # f20 and libvirt 1.1.3
+        "/sys/fs/cgroup/%s/machine.slice/%s"%(subsystem2, 
+                                              virSystemdMakeScopeName(slice_name,'lxc','machine')),
+        ]
+    return find_first_dir (candidates)
+
+#################### end of libvirtsystemd.py
+
 def getarch(f):
     output = os.popen('readelf -h %s 2>&1'%f).readlines()
     classlines = [x for x in output if ('Class' in x.split(':')[0])]
@@ -23,6 +147,22 @@ def getarch(f):
     else:
         raise Exception('Could not determine architecture')
 
+def get_cgroup_subdirs_for_pid(pid):
+    cgroup_info_file = '/proc/%s/cgroup'%pid
+    cgroup_lines = open(cgroup_info_file).read().splitlines()
+    
+    subdirs = {}
+    for line in cgroup_lines:
+        try:
+            _, cgroup_name, subdir = line.split(':')
+            subdirs[cgroup_name] = subdir
+        except Exception, e:
+            print "Error reading cgroup info: %s"%str(e)
+            pass
+    
+    return subdirs
+        
+    
 def umount(fs_dir, opts=''):
     output = os.popen('/bin/umount %s %s 2>&1'%(opts, fs_dir)).read()
     return ('device is busy' not in output)
@@ -115,37 +255,51 @@ def main ():
                sysctl_val = open(sysctl_file).read()
                sysctls.append((sysctl_file, sysctl_name, sysctl_val))
 
-    # Enter cgroups
-    try:
-       for subsystem in ['cpuset','memory','blkio']:
-           open('/sys/fs/cgroup/%s/libvirt/lxc/%s/tasks'%(subsystem,slice_name),'w').write(str(os.getpid()))
-
-    except Exception,e:
-       if debug: print e 
-       print "Error assigning resources: %s"%slice_name
-       exit(1)
-
-    try:
-        open('/sys/fs/cgroup/cpuacct/system/libvirtd.service/libvirt/lxc/%s/tasks'%slice_name,'w').write(str(os.getpid()))
-    except Exception,e:
-       if debug: print e 
-       print "Error assigning cpuacct: %s" % slice_name
-       exit(1)
+    subdirs = get_cgroup_subdirs_for_pid(pid) 
+    sysfs_root = '/sys/fs/cgroup'
 
     # If the slice is frozen, then we'll get an EBUSY when trying to write to the task
     # list for the freezer cgroup. Since the user couldn't do anything anyway, it's best
     # in this case to error out the shell. (an alternative would be to un-freeze it,
     # add the task, and re-freeze it)
-    try:
-       f=open('/sys/fs/cgroup/freezer/libvirt/lxc/%s/tasks'%(slice_name),'w')
-       f.write(str(os.getpid()))
-       # note: we need to call f.close() explicitly, or we'll get an exception in
-       # the object destructor, which will not be caught
-       f.close()
-    except Exception,e:
-       if debug: print e 
-       print "Error adding task to freezer cgroup. Slice is probably frozen: %s" % slice_name
-       exit(1)
+    # Enter cgroups
+    current_cgroup = ''
+    for subsystem in ['cpuset','memory','blkio','cpuacct','cpuacct,cpu','freezer']:
+        try:
+            current_cgroup = subsystem
+
+            # There seems to be a bug in the cgroup schema: cpuacct,cpu can become cpu,cpuacct
+            # We need to handle both
+            task_path_alt = None
+            try:
+               subsystem_comps = subsystem.split(',')
+               subsystem_comps.reverse()
+               subsystem_alt = ','.join(subsystem_comps)
+               tasks_path_alt = [sysfs_root, subsystem_alt, subdirs[subsystem], 'tasks']
+            except Exception,e:
+                pass
+               
+            tasks_path = [sysfs_root,subsystem,subdirs[subsystem],'tasks']
+            tasks_path_str = '/'.join(tasks_path)
+     
+            try:
+                f = open(tasks_path_str, 'w')
+            except:
+                tasks_path_alt_str = '/'.join(tasks_path_alt)
+                f = open(tasks_path_alt_str, 'w')
+
+            f.write(str(os.getpid()))
+            if (subsystem=='freezer'):
+                f.close()
+
+        except Exception,e:
+            if (not subdirs.has_key(subsystem)):
+                pass
+            else:
+                if debug: print e 
+                print "Error assigning cgroup %s (%s) for slice %s"%(current_cgroup,pid, slice_name)
+                exit(1)
+
 
     setns.chcontext('/proc/%s/ns/uts'%pid)
     setns.chcontext('/proc/%s/ns/ipc'%pid)