From aa938247e19afa419476fb2d0b7cb2d054c6dd47 Mon Sep 17 00:00:00 2001 From: Emmanuel Dreyfus Date: Wed, 29 Apr 2015 15:52:37 +0200 Subject: Tests: use a portable way to flush kernel cache On Linux, kernel cache can be flushed using echo 3 > /proc/sys/vm/drop_caches This non-portable approach can be replaced by an on-purpose failed attempt to unmount: if the mount point is the current directory and umount is called, the kernel will flush inodes until it realize it cannot complete the operation because root of filesystem is busy: ( cd $M0 ; umount $M0 ) Unfortunately this does not flush everything. Entries may still be present in the kenrel FUSE cache. Using $GFS to mount the filesystem ensure --entry-timeout=0 and clears this problem. Some stall information may also remain in glusterfs caches, and that may have to be adressed by appropriate volume option. For instance tests/bugs/rpc/bug-954057.t needs to disable performance.stat-prefetch. Qtherwise, root's new credentials are not evaluated after root-quash is enabled. The test could also be done with performance.stat-prefetch enabled using various tricks: copying the file to read, creating a hard link on it, or just waiting long enough for metadata cache to expire. BUG: 1129939 Change-Id: I54929e899d55c04dcd9d947809133549f01fd0e1 Signed-off-by: Emmanuel Dreyfus Reviewed-on: http://review.gluster.org/10411 Reviewed-by: Dan Lambright Tested-by: Gluster Build System Reviewed-by: Vijay Bellur --- tests/bugs/rpc/bug-954057.t | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) (limited to 'tests/bugs/rpc/bug-954057.t') diff --git a/tests/bugs/rpc/bug-954057.t b/tests/bugs/rpc/bug-954057.t index 9c48207b711..faaf261d88b 100755 --- a/tests/bugs/rpc/bug-954057.t +++ b/tests/bugs/rpc/bug-954057.t @@ -3,15 +3,25 @@ . $(dirname $0)/../../include.rc . $(dirname $0)/../../volume.rc -#This script checks if use-readdirp option works as accepted in mount options - +# This script checks if use-readdirp option works as accepted in mount options + +# Note on re-reading $M0/new after enabling root-squash: +# Since we have readen it once, the file is present in various caches. +# In order to actually fail on second attempt we must: +# 1) drop kernel cache, by ( cd $M0 ; umount $M0 ) +# 2) make sure FUSE does not cache the entry. This is also +# in the kernel, but not flushed by a failed umount. +# Using $GFS enforces this because it sets --entry-timeout=0 +# 3) make sure reading new permissins does not produce stale +# information from glusterfs metadata cache. Setting volume +# option performance.stat-prefetch off enforces that. TEST glusterd TEST pidof glusterd TEST $CLI volume create $V0 $H0:$B0/${V0} TEST $CLI volume start $V0 -TEST glusterfs --volfile-id=/$V0 --volfile-server=$H0 $M0 +TEST $GFS --volfile-id=/$V0 --volfile-server=$H0 $M0 TEST mkdir $M0/dir TEST mkdir $M0/nobody @@ -21,8 +31,9 @@ TEST cp $M0/file $M0/new TEST chmod 700 $M0/new TEST cat $M0/new +TEST $CLI volume set $V0 performance.stat-prefetch off TEST $CLI volume set $V0 server.root-squash enable -TEST `echo 3 > /proc/sys/vm/drop_caches` +( cd $M0 ; umount $M0 ) # fails but drops kernel cache TEST ! mkdir $M0/other TEST mkdir $M0/nobody/other TEST cat $M0/file @@ -30,7 +41,7 @@ TEST ! cat $M0/new TEST `echo "nobody" >> $M0/nobody/file` #mount the client without root-squashing -TEST glusterfs --volfile-id=/$V0 --volfile-server=$H0 --no-root-squash=yes $M1 +TEST $GFS --volfile-id=/$V0 --volfile-server=$H0 --no-root-squash=yes $M1 TEST mkdir $M1/m1_dir TEST `echo "file" >> $M1/m1_file` TEST cp $M0/file $M1/new -- cgit