| Message ID | 1423532117-14490-17-git-send-email-jsnow@redhat.com |
|---|---|
| State | New |
| Headers | show |
On 2015-02-09 at 20:35, John Snow wrote: > Background: > The blkdebug scripts are currently engineered so that when a debug > event occurs, a prefilter browses a master list of parsed rules for a > certain event and adds them to an "active list" of rules to be used for > the forthcoming action, provided the events and state numbers match. > > Then, once the request is received, the last active rule is used to > inject an error if certain parameters match. > > This active list is cleared every time the prefilter injects a new > rule for the first time during a debug event. > > The "once" rule currently causes the error injection, if it is > triggered, to only clear the active list. This is insufficient for > preventing future injections of the same rule. > > Remedy: > This patch /deletes/ the rule from the list that the prefilter > browses, so it is gone for good. In V2, we remove only the rule of > interest from the active list instead of allowing the "once" rule to > clear the entire list of active rules. > > Impact: > This affects iotests 026. Several ENOSPC tests that used "once" can > be seen to have output that shows multiple failure messages. After > this patch, the error messages tend to be smaller and less severe, but > the injection can still be seen to be working. I have patched the > expected output to expect the smaller error messages. > > Signed-off-by: John Snow <jsnow@redhat.com> > --- > block/blkdebug.c | 6 ++++-- > tests/qemu-iotests/026.out | 24 ++++-------------------- > 2 files changed, 8 insertions(+), 22 deletions(-) Well, I think this shouldn't be part of this series, but you can find my R-b here: http://lists.nongnu.org/archive/html/qemu-devel/2015-02/msg01209.html Max
On 02/11/2015 04:50 PM, Max Reitz wrote: > On 2015-02-09 at 20:35, John Snow wrote: >> Background: >> The blkdebug scripts are currently engineered so that when a debug >> event occurs, a prefilter browses a master list of parsed rules for a >> certain event and adds them to an "active list" of rules to be used for >> the forthcoming action, provided the events and state numbers match. >> >> Then, once the request is received, the last active rule is used to >> inject an error if certain parameters match. >> >> This active list is cleared every time the prefilter injects a new >> rule for the first time during a debug event. >> >> The "once" rule currently causes the error injection, if it is >> triggered, to only clear the active list. This is insufficient for >> preventing future injections of the same rule. >> >> Remedy: >> This patch /deletes/ the rule from the list that the prefilter >> browses, so it is gone for good. In V2, we remove only the rule of >> interest from the active list instead of allowing the "once" rule to >> clear the entire list of active rules. >> >> Impact: >> This affects iotests 026. Several ENOSPC tests that used "once" can >> be seen to have output that shows multiple failure messages. After >> this patch, the error messages tend to be smaller and less severe, but >> the injection can still be seen to be working. I have patched the >> expected output to expect the smaller error messages. >> >> Signed-off-by: John Snow <jsnow@redhat.com> >> --- >> block/blkdebug.c | 6 ++++-- >> tests/qemu-iotests/026.out | 24 ++++-------------------- >> 2 files changed, 8 insertions(+), 22 deletions(-) > > Well, I think this shouldn't be part of this series, but you can find my > R-b here: > http://lists.nongnu.org/archive/html/qemu-devel/2015-02/msg01209.html > > Max I will need to do a version bump to address patches 7-9, fix error messages, and other house-cleaning issues. I can just put in the cover letter that this series *depends* on that other patch. Otherwise, this series can be merged up to this patch before it's actually needed and it won't have any ill effect. --js
diff --git a/block/blkdebug.c b/block/blkdebug.c index 9ce35cd..63611e0 100644 --- a/block/blkdebug.c +++ b/block/blkdebug.c @@ -472,12 +472,14 @@ static BlockAIOCB *inject_error(BlockDriverState *bs, int error = rule->options.inject.error; struct BlkdebugAIOCB *acb; QEMUBH *bh; + bool immediately = rule->options.inject.immediately; if (rule->options.inject.once) { - QSIMPLEQ_INIT(&s->active_rules); + QSIMPLEQ_REMOVE(&s->active_rules, rule, BlkdebugRule, active_next); + remove_rule(rule); } - if (rule->options.inject.immediately) { + if (immediately) { return NULL; } diff --git a/tests/qemu-iotests/026.out b/tests/qemu-iotests/026.out index 524f7ee..5e964fb 100644 --- a/tests/qemu-iotests/026.out +++ b/tests/qemu-iotests/026.out @@ -140,19 +140,13 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: l2_update; errno: 5; imm: off; once: on; write -Failed to flush the L2 table cache: Input/output error write failed: Input/output error - -127 leaked clusters were found on the image. -This means waste of disk space, but no harm to data. +No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: l2_update; errno: 5; imm: off; once: on; write -b -Failed to flush the L2 table cache: Input/output error write failed: Input/output error - -127 leaked clusters were found on the image. -This means waste of disk space, but no harm to data. +No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: l2_update; errno: 5; imm: off; once: off; write @@ -174,19 +168,13 @@ This means waste of disk space, but no harm to data. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: l2_update; errno: 28; imm: off; once: on; write -Failed to flush the L2 table cache: No space left on device write failed: No space left on device - -127 leaked clusters were found on the image. -This means waste of disk space, but no harm to data. +No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: l2_update; errno: 28; imm: off; once: on; write -b -Failed to flush the L2 table cache: No space left on device write failed: No space left on device - -127 leaked clusters were found on the image. -This means waste of disk space, but no harm to data. +No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: l2_update; errno: 28; imm: off; once: off; write @@ -356,13 +344,11 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_update_part; errno: 5; imm: off; once: on; write -Failed to flush the refcount block cache: Input/output error write failed: Input/output error No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_update_part; errno: 5; imm: off; once: on; write -b -Failed to flush the refcount block cache: Input/output error write failed: Input/output error No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 @@ -382,13 +368,11 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_update_part; errno: 28; imm: off; once: on; write -Failed to flush the refcount block cache: No space left on device write failed: No space left on device No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_update_part; errno: 28; imm: off; once: on; write -b -Failed to flush the refcount block cache: No space left on device write failed: No space left on device No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824
Background: The blkdebug scripts are currently engineered so that when a debug event occurs, a prefilter browses a master list of parsed rules for a certain event and adds them to an "active list" of rules to be used for the forthcoming action, provided the events and state numbers match. Then, once the request is received, the last active rule is used to inject an error if certain parameters match. This active list is cleared every time the prefilter injects a new rule for the first time during a debug event. The "once" rule currently causes the error injection, if it is triggered, to only clear the active list. This is insufficient for preventing future injections of the same rule. Remedy: This patch /deletes/ the rule from the list that the prefilter browses, so it is gone for good. In V2, we remove only the rule of interest from the active list instead of allowing the "once" rule to clear the entire list of active rules. Impact: This affects iotests 026. Several ENOSPC tests that used "once" can be seen to have output that shows multiple failure messages. After this patch, the error messages tend to be smaller and less severe, but the injection can still be seen to be working. I have patched the expected output to expect the smaller error messages. Signed-off-by: John Snow <jsnow@redhat.com> --- block/blkdebug.c | 6 ++++-- tests/qemu-iotests/026.out | 24 ++++-------------------- 2 files changed, 8 insertions(+), 22 deletions(-)