Changeset 543

Timestamp:

12/15/2011 16:59:40 (5 months ago)

Author:

ccowart

Message:

WIP: Fixing race condition.

Overall design change:

• Commit modules in _reverse_ order
• Keep a list of "committed" files and don't re-commit if we encounter the same filesystem path in a later module

I need some help reviewing this change, especially as it relates to the
install operation; I'm not convinced the implementation is complete yet.

See #120.

Location:

branches/confman-1.9

Files:

• confaudit.in (modified) (2 diffs)
• confman.in (modified) (9 diffs)
• confmanlib.sh.in (modified) (7 diffs)
• confsync.in (modified) (2 diffs)

branches/confman-1.9/confaudit.in

@@ -109 +109 @@
 tmproot=$(conf_tmp_dir)
 live_root="${LIVE_ROOT}"
+statefile=$(conf_tmp_file)
 
 # Override LIVE_ROOT to commit into our temporary directory.
@@ -116 +117 @@
 for layer in $(conf_get_recipe) ; do
     echo "Rolling on $layer..."
-    conf_rollout $layer || conf_cleanExit
+    conf_rollout $layer $statefile || conf_cleanExit
 done
 for file in $SINGULARITIES ; do

branches/confman-1.9/confman.in

@@ -189 +189 @@
 
 function commit {
-    local msg status modules module symlink abswork files
+    local msg status modules module symlink abswork files statefile
     local nocommit=true
     local opt OPTIND OPTARG
@@ -212 +212 @@
     abswork=$(conf_abswork)
     
-    for module in $(conf_get_recipe); do
+    for module in $(conf_get_reverse_recipe); do
         modules=${modules:+${modules} }${module}
         for symlink in $(find ${WORK_PATH}/${module} \
@@ -236 +236 @@
     echo "Commit operation started" >&2
     $nocommit || conf_commit_file $msg $files || return $?
-    for layer in $(conf_get_recipe) ; do
+    statefile=$(conf_tmp_file)
+    for layer in $(conf_get_reverse_recipe) ; do
         echo "Rolling on $layer..."
-        conf_rollout $layer || return $?
+        conf_rollout $layer $statefile || return $?
     done
     for file in $SINGULARITIES ; do
@@ -259 +260 @@
     local opt OPTIND OPTARG
     local module
+    local statefile
 
     while getopts ":m:F:" opt ; do
@@ -292 +294 @@
     $nocommit || conf_commit_file "$msg" "$files" || return $?
     
-    for layer in $(conf_get_recipe) ; do
+    for layer in $(conf_get_reverse_recipe) ; do
         for file in "$@"; do
             module=$(conf_wfile_module $file)
             if conf_wfile_is_singularity $file; then
-                conf_install $layer "${file%-$module}-${layer}"
+                conf_install $layer $statefile "${file%-$module}-${layer}"
             else
-                conf_install $layer "$file"
+                conf_install $layer $statefile "$file"
             fi
         done
@@ -761 +763 @@
     local checkpoint=$2
     local clock=$3
-    local wcopy_lock system_lock
+    local wcopy_lock system_lock statefile
 
     if [ -z "$2" ] ; then
@@ -771 +773 @@
         echo "Rolling $module back to $checkpoint $clock" >&2
         conf_rollback $module $checkpoint $clock || conf_cleanExit
-        for layer in $(conf_get_recipe) ; do
+        statefile=$(conf_tmp_file)
+        for layer in $(conf_get_reverse_recipe) ; do
             echo "Rolling on $layer..."
-            conf_rollout $layer || conf_cleanExit
+            conf_rollout $layer $statefile || conf_cleanExit
         done
 
@@ -925 +928 @@
         local tmproot=$(conf_tmp_dir)
         local live_root="${LIVE_ROOT}"
+        local statefile
 
         # Override LIVE_ROOT to commit into our tmporary directory.
@@ -932 +936 @@
 
         echo "Audit operation started" >&2
-        for layer in $(conf_get_recipe) ; do
+        for layer in $(conf_get_reverse_recipe) ; do
             echo "Rolling on $layer..."
-            conf_rollout $layer || return $?
+            conf_rollout $layer $statefile || return $?
         done >/dev/null
         for file in $SINGULARITIES ; do

branches/confman-1.9/confmanlib.sh.in

@@ -414 +414 @@
 }
 
+# Test to see if the pathname has been added to a statefile yet
+function conf_beenthere {
+    local statefile="$1"
+    local pathname="$2"
+    fgrep -q "$pathname" "$statefile"
+}
+
+# Record this file in the given statefile
+function conf_gothere {
+    local statefile="$1"
+    local pathname="$2"
+    echo "$pathname" >> $statefile
+}
+
 # Roll out the specified module, optionally at the specified checkpoint
-# eg:   conf_rollout MODULE [checkpoint]
+# A statefile is a place to record the files that have been rolled out to
+# prevent a lower-priority module from installing a committed file.
+# eg:   conf_rollout MODULE STATEFILE [checkpoint]
 function conf_rollout {
         local module="$1"
-        if [ -z $2 ] ; then
+    local statefile="$2"
+        if [ -z $3 ] ; then
                 local moduledir="${WORK_PATH}/$module"
         else 
@@ -436 +453 @@
                 local livedir=`echo $directory | ${sed_cmd} -e "s:$moduledir::"`
                 livedir="${LIVE_ROOT}${livedir}"
-                local owner=`conf_get_prop ${directory} owner`
-                local group=`conf_get_prop ${directory} group`
-                local mode=`conf_get_prop ${directory} mode`
-                local opts="-d -o $owner -g $group -m $mode"
-                local cmd="$SUDO $install_cmd $opts $livedir"
-                echo $cmd
-                $cmd
-        done
+        if ! conf_beenthere $statefile "$livedir" ; then
+                    local owner=`conf_get_prop ${directory} owner`
+                    local group=`conf_get_prop ${directory} group`
+                    local mode=`conf_get_prop ${directory} mode`
+                    local opts="-d -o $owner -g $group -m $mode"
+                    local cmd="$SUDO $install_cmd $opts $livedir"
+                    echo $cmd
+            conf_gothere $statefile "$livedir"
+                    $cmd
+        fi
+        done    
         for file in `find -L $moduledir -type f | grep -v "\.svn"` ; do
                 local livefile=`echo "$file" | ${sed_cmd} -e "s:$moduledir::"`
@@ -450 +470 @@
                 local mode=`conf_get_prop ${file} mode`
         local symlink="`conf_get_prop ${file} symlink`"
-        file=`$readlink_cmd -m $file`
-        if [ -n "$symlink" ]; then
-            local cmd="$SUDO ln -snf $symlink ${LIVE_ROOT}$livefile"
-            echo $cmd
-            $cmd
-        else
-                    local opts="-o $owner -g $group -m $mode"
-                    local cmd="$SUDO $install_cmd $opts $file ${LIVE_ROOT}$livefile"
+        livefile="${LIVE_ROOT}${livefile}"
+        if ! conf_beenthere $statefile "$livefile" ; then
+            file=`$readlink_cmd -m $file`
+            if [ -n "$symlink" ]; then
+                local cmd="$SUDO ln -snf $symlink $livefile"
+            else
+                        local opts="-o $owner -g $group -m $mode"
+                        local cmd="$SUDO $install_cmd $opts $file $livefile"
+            fi
                     echo $cmd
+            conf_gothere $statefile "$livefile"
                     $cmd
         fi
@@ -539 +561 @@
     ABS_WORK=$(${readlink_cmd} -m "$WORK_PATH")
         local module="$1"
-    local file="$2"
+    local statefile="$2"
+    local file="$3"
     shift 2
     local livefile
@@ -553 +576 @@
     livefile="/${file#*/}"
     file="${ABS_WORK}/${module}${livefile}"
+    livefile="${LIVE_ROOT}${livefile}"
 
         # See if it even exists
     if [ ! -e "$file" ] ; then
         conf_debug "$file" does not appear to exist
-        conf_install $module "$@"
+        conf_install $module $statefile "$@"
         return 1
     fi
@@ -574 +598 @@
     
     if [ -n "$symlink" ] ; then
-        local cmd="$SUDO ln -snf $symlink ${LIVE_ROOT}$livefile"
-    else
-            local cmd="$SUDO $install_cmd $opts $file ${LIVE_ROOT}$livefile"
-    fi
-
-        ${NFS_HACK:-false} && chmod o+rx ${ABS_WORK}
-        echo $cmd
-        $cmd || failures=true
-        ${NFS_HACK:-false} && chmod o-rx ${ABS_WORK}
+        local cmd="$SUDO ln -snf $symlink $livefile"
+    else
+            local cmd="$SUDO $install_cmd $opts $file $livefile"
+    fi
+
+    if ! conf_beenthere $statefile "$livefile" ; then
+            ${NFS_HACK:-false} && chmod o+rx ${ABS_WORK}
+            echo $cmd
+        conf_gothere $statefile "$lifefile"
+            $cmd || failures=true
+            ${NFS_HACK:-false} && chmod o-rx ${ABS_WORK}
+    fi
 
     if [ -d "$file" ] ; then
         conf_debug "conf_install encountered a directory. Recursing."
-        conf_install $module $(find "$file" \
+        conf_install $module $statefile $(find "$file" \
             -mindepth 1 -maxdepth 1 -not -name '.svn') || failures=true
     fi
     conf_debug "conf_install recursing"
-        conf_install $module "$@" || failures=true
+        conf_install $module $statefile "$@" || failures=true
     conf_debug "conf_install returning"
     if $failures ; then 
@@ -1013 +1040 @@
 }
 
+# Gets a reversed copy of the recipe
+function conf_get_reverse_recipe {
+    local fwd_recipe=$(conf_get_recipe "$@")
+    local rev_recipe
+    for module in $fwd_recipe ; do
+        rev_recipe="$module $rev_recipe"
+    done
+    echo $rev_recipe
+}
+
 # Spits the recipe, modules separated by whitespace, out on stdout
 function conf_get_recipe {

branches/confman-1.9/confsync.in

@@ -116 +116 @@
 sys_revision=`conf_sysrev`
 last_action=$(conf_lastact)
+statefile=$(conf_tmp_file)
 
 if [ "x$last_action" = "xinstall" ] && [ $tar_revision -lt $sys_revision ]
@@ -139 +140 @@
 for layer in $(conf_get_recipe) ; do
     echo "Rolling on $layer..."
-    conf_rollout $layer || conf_cleanExit
+    conf_rollout $layer $statefile || conf_cleanExit
 done
 for file in $SINGULARITIES ; do