| Message ID | cover.1599813294.git.dimastep@yandex-team.ru |
|---|---|
| Headers | show |
| Series | vhost-user-blk: fix the migration issue and enhance qtests | expand |
On Fri, Sep 11, 2020 at 11:39:42AM +0300, Dima Stepanov wrote: > v4 -> v5: > - vhost: check queue state in the vhost_dev_set_log routine > tests/qtest/vhost-user-test: prepare the tests for adding new > dev class > tests/qtest/vhost-user-test: add support for the > vhost-user-blk device > tests/qtest/vhost-user-test: add migrate_reconnect test > Reviewed-by: Raphael Norwitz > - Update qtest, by merging vhost-user-blk "if" case with the > virtio-blk case. I dropped patches 3-7 since they were stalling on some systems. Pls work with Peter Maydell (cc'd) to figure it out. > v3 -> v4: > - vhost: recheck dev state in the vhost_migration_log routine > Reviewed-by: Raphael Norwitz > - vhost: check queue state in the vhost_dev_set_log routine > Use "continue" instead of "break" to handle non-initialized > virtqueue case. > > v2 -> v3: > - update commit message for the > "vhost: recheck dev state in the vhost_migration_log routine" commit > - rename "started" field of the VhostUserBlk structure to > "started_vu", so there will be no confustion with the VHOST started > field > - update vhost-user-test.c to always initialize nq local variable > (spotted by patchew) > > v1 -> v2: > - add comments to connected/started fields in the header file > - move the "s->started" logic from the vhost_user_blk_disconnect > routine to the vhost_user_blk_stop routine > > Reference e-mail threads: > - https://lists.gnu.org/archive/html/qemu-devel/2020-05/msg01509.html > - https://lists.gnu.org/archive/html/qemu-devel/2020-05/msg05241.html > > If vhost-user daemon is used as a backend for the vhost device, then we > should consider a possibility of disconnect at any moment. There was a general > question here: should we consider it as an error or okay state for the vhost-user > devices during migration process? > I think the disconnect event for the vhost-user devices should not break the > migration process, because: > - the device will be in the stopped state, so it will not be changed > during migration > - if reconnect will be made the migration log will be reinitialized as > part of reconnect/init process: > #0 vhost_log_global_start (listener=0x563989cf7be0) > at hw/virtio/vhost.c:920 > #1 0x000056398603d8bc in listener_add_address_space (listener=0x563989cf7be0, > as=0x563986ea4340 <address_space_memory>) > at softmmu/memory.c:2664 > #2 0x000056398603dd30 in memory_listener_register (listener=0x563989cf7be0, > as=0x563986ea4340 <address_space_memory>) > at softmmu/memory.c:2740 > #3 0x0000563985fd6956 in vhost_dev_init (hdev=0x563989cf7bd8, > opaque=0x563989cf7e30, backend_type=VHOST_BACKEND_TYPE_USER, > busyloop_timeout=0) > at hw/virtio/vhost.c:1385 > #4 0x0000563985f7d0b8 in vhost_user_blk_connect (dev=0x563989cf7990) > at hw/block/vhost-user-blk.c:315 > #5 0x0000563985f7d3f6 in vhost_user_blk_event (opaque=0x563989cf7990, > event=CHR_EVENT_OPENED) > at hw/block/vhost-user-blk.c:379 > The first patch in the patchset fixes this issue by setting vhost device to the > stopped state in the disconnect handler and check it the vhost_migration_log() > routine before returning from the function. > qtest framework was updated to test vhost-user-blk functionality. The > vhost-user-blk/vhost-user-blk-tests/migrate_reconnect test was added to reproduce > the original issue found. > > Dima Stepanov (7): > vhost: recheck dev state in the vhost_migration_log routine > vhost: check queue state in the vhost_dev_set_log routine > tests/qtest/vhost-user-test: prepare the tests for adding new dev > class > tests/qtest/libqos/virtio-blk: add support for vhost-user-blk > tests/qtest/vhost-user-test: add support for the vhost-user-blk device > tests/qtest/vhost-user-test: add migrate_reconnect test > tests/qtest/vhost-user-test: enable the reconnect tests > > hw/block/vhost-user-blk.c | 19 ++- > hw/virtio/vhost.c | 39 ++++- > include/hw/virtio/vhost-user-blk.h | 10 ++ > tests/qtest/libqos/virtio-blk.c | 14 +- > tests/qtest/vhost-user-test.c | 290 +++++++++++++++++++++++++++++++------ > 5 files changed, 322 insertions(+), 50 deletions(-) > > -- > 2.7.4
On Thu, Sep 24, 2020 at 07:26:14AM -0400, Michael S. Tsirkin wrote: > On Fri, Sep 11, 2020 at 11:39:42AM +0300, Dima Stepanov wrote: > > v4 -> v5: > > - vhost: check queue state in the vhost_dev_set_log routine > > tests/qtest/vhost-user-test: prepare the tests for adding new > > dev class > > tests/qtest/vhost-user-test: add support for the > > vhost-user-blk device > > tests/qtest/vhost-user-test: add migrate_reconnect test > > Reviewed-by: Raphael Norwitz > > - Update qtest, by merging vhost-user-blk "if" case with the > > virtio-blk case. > > I dropped patches 3-7 since they were stalling on some systems. > Pls work with Peter Maydell (cc'd) to figure it out. Thanks! Peter, can you share any details for the stalling errors with me? > > > > v3 -> v4: > > - vhost: recheck dev state in the vhost_migration_log routine > > Reviewed-by: Raphael Norwitz > > - vhost: check queue state in the vhost_dev_set_log routine > > Use "continue" instead of "break" to handle non-initialized > > virtqueue case. > > > > v2 -> v3: > > - update commit message for the > > "vhost: recheck dev state in the vhost_migration_log routine" commit > > - rename "started" field of the VhostUserBlk structure to > > "started_vu", so there will be no confustion with the VHOST started > > field > > - update vhost-user-test.c to always initialize nq local variable > > (spotted by patchew) > > > > v1 -> v2: > > - add comments to connected/started fields in the header file > > - move the "s->started" logic from the vhost_user_blk_disconnect > > routine to the vhost_user_blk_stop routine > > > > Reference e-mail threads: > > - https://lists.gnu.org/archive/html/qemu-devel/2020-05/msg01509.html > > - https://lists.gnu.org/archive/html/qemu-devel/2020-05/msg05241.html > > > > If vhost-user daemon is used as a backend for the vhost device, then we > > should consider a possibility of disconnect at any moment. There was a general > > question here: should we consider it as an error or okay state for the vhost-user > > devices during migration process? > > I think the disconnect event for the vhost-user devices should not break the > > migration process, because: > > - the device will be in the stopped state, so it will not be changed > > during migration > > - if reconnect will be made the migration log will be reinitialized as > > part of reconnect/init process: > > #0 vhost_log_global_start (listener=0x563989cf7be0) > > at hw/virtio/vhost.c:920 > > #1 0x000056398603d8bc in listener_add_address_space (listener=0x563989cf7be0, > > as=0x563986ea4340 <address_space_memory>) > > at softmmu/memory.c:2664 > > #2 0x000056398603dd30 in memory_listener_register (listener=0x563989cf7be0, > > as=0x563986ea4340 <address_space_memory>) > > at softmmu/memory.c:2740 > > #3 0x0000563985fd6956 in vhost_dev_init (hdev=0x563989cf7bd8, > > opaque=0x563989cf7e30, backend_type=VHOST_BACKEND_TYPE_USER, > > busyloop_timeout=0) > > at hw/virtio/vhost.c:1385 > > #4 0x0000563985f7d0b8 in vhost_user_blk_connect (dev=0x563989cf7990) > > at hw/block/vhost-user-blk.c:315 > > #5 0x0000563985f7d3f6 in vhost_user_blk_event (opaque=0x563989cf7990, > > event=CHR_EVENT_OPENED) > > at hw/block/vhost-user-blk.c:379 > > The first patch in the patchset fixes this issue by setting vhost device to the > > stopped state in the disconnect handler and check it the vhost_migration_log() > > routine before returning from the function. > > qtest framework was updated to test vhost-user-blk functionality. The > > vhost-user-blk/vhost-user-blk-tests/migrate_reconnect test was added to reproduce > > the original issue found. > > > > Dima Stepanov (7): > > vhost: recheck dev state in the vhost_migration_log routine > > vhost: check queue state in the vhost_dev_set_log routine > > tests/qtest/vhost-user-test: prepare the tests for adding new dev > > class > > tests/qtest/libqos/virtio-blk: add support for vhost-user-blk > > tests/qtest/vhost-user-test: add support for the vhost-user-blk device > > tests/qtest/vhost-user-test: add migrate_reconnect test > > tests/qtest/vhost-user-test: enable the reconnect tests > > > > hw/block/vhost-user-blk.c | 19 ++- > > hw/virtio/vhost.c | 39 ++++- > > include/hw/virtio/vhost-user-blk.h | 10 ++ > > tests/qtest/libqos/virtio-blk.c | 14 +- > > tests/qtest/vhost-user-test.c | 290 +++++++++++++++++++++++++++++++------ > > 5 files changed, 322 insertions(+), 50 deletions(-) > > > > -- > > 2.7.4 >
On Sun, Sep 27, 2020 at 09:48:28AM +0300, Dima Stepanov wrote: > On Thu, Sep 24, 2020 at 07:26:14AM -0400, Michael S. Tsirkin wrote: > > On Fri, Sep 11, 2020 at 11:39:42AM +0300, Dima Stepanov wrote: > > > v4 -> v5: > > > - vhost: check queue state in the vhost_dev_set_log routine > > > tests/qtest/vhost-user-test: prepare the tests for adding new > > > dev class > > > tests/qtest/vhost-user-test: add support for the > > > vhost-user-blk device > > > tests/qtest/vhost-user-test: add migrate_reconnect test > > > Reviewed-by: Raphael Norwitz > > > - Update qtest, by merging vhost-user-blk "if" case with the > > > virtio-blk case. > > > > I dropped patches 3-7 since they were stalling on some systems. > > Pls work with Peter Maydell (cc'd) to figure it out. > Thanks! > > Peter, can you share any details for the stalling errors with me? I can say for sure that even on x86/linux the affected tests take much longer to run with these applied. I'd suggest making sure there are no timeouts involved in the good case .... > > > > > > > v3 -> v4: > > > - vhost: recheck dev state in the vhost_migration_log routine > > > Reviewed-by: Raphael Norwitz > > > - vhost: check queue state in the vhost_dev_set_log routine > > > Use "continue" instead of "break" to handle non-initialized > > > virtqueue case. > > > > > > v2 -> v3: > > > - update commit message for the > > > "vhost: recheck dev state in the vhost_migration_log routine" commit > > > - rename "started" field of the VhostUserBlk structure to > > > "started_vu", so there will be no confustion with the VHOST started > > > field > > > - update vhost-user-test.c to always initialize nq local variable > > > (spotted by patchew) > > > > > > v1 -> v2: > > > - add comments to connected/started fields in the header file > > > - move the "s->started" logic from the vhost_user_blk_disconnect > > > routine to the vhost_user_blk_stop routine > > > > > > Reference e-mail threads: > > > - https://lists.gnu.org/archive/html/qemu-devel/2020-05/msg01509.html > > > - https://lists.gnu.org/archive/html/qemu-devel/2020-05/msg05241.html > > > > > > If vhost-user daemon is used as a backend for the vhost device, then we > > > should consider a possibility of disconnect at any moment. There was a general > > > question here: should we consider it as an error or okay state for the vhost-user > > > devices during migration process? > > > I think the disconnect event for the vhost-user devices should not break the > > > migration process, because: > > > - the device will be in the stopped state, so it will not be changed > > > during migration > > > - if reconnect will be made the migration log will be reinitialized as > > > part of reconnect/init process: > > > #0 vhost_log_global_start (listener=0x563989cf7be0) > > > at hw/virtio/vhost.c:920 > > > #1 0x000056398603d8bc in listener_add_address_space (listener=0x563989cf7be0, > > > as=0x563986ea4340 <address_space_memory>) > > > at softmmu/memory.c:2664 > > > #2 0x000056398603dd30 in memory_listener_register (listener=0x563989cf7be0, > > > as=0x563986ea4340 <address_space_memory>) > > > at softmmu/memory.c:2740 > > > #3 0x0000563985fd6956 in vhost_dev_init (hdev=0x563989cf7bd8, > > > opaque=0x563989cf7e30, backend_type=VHOST_BACKEND_TYPE_USER, > > > busyloop_timeout=0) > > > at hw/virtio/vhost.c:1385 > > > #4 0x0000563985f7d0b8 in vhost_user_blk_connect (dev=0x563989cf7990) > > > at hw/block/vhost-user-blk.c:315 > > > #5 0x0000563985f7d3f6 in vhost_user_blk_event (opaque=0x563989cf7990, > > > event=CHR_EVENT_OPENED) > > > at hw/block/vhost-user-blk.c:379 > > > The first patch in the patchset fixes this issue by setting vhost device to the > > > stopped state in the disconnect handler and check it the vhost_migration_log() > > > routine before returning from the function. > > > qtest framework was updated to test vhost-user-blk functionality. The > > > vhost-user-blk/vhost-user-blk-tests/migrate_reconnect test was added to reproduce > > > the original issue found. > > > > > > Dima Stepanov (7): > > > vhost: recheck dev state in the vhost_migration_log routine > > > vhost: check queue state in the vhost_dev_set_log routine > > > tests/qtest/vhost-user-test: prepare the tests for adding new dev > > > class > > > tests/qtest/libqos/virtio-blk: add support for vhost-user-blk > > > tests/qtest/vhost-user-test: add support for the vhost-user-blk device > > > tests/qtest/vhost-user-test: add migrate_reconnect test > > > tests/qtest/vhost-user-test: enable the reconnect tests > > > > > > hw/block/vhost-user-blk.c | 19 ++- > > > hw/virtio/vhost.c | 39 ++++- > > > include/hw/virtio/vhost-user-blk.h | 10 ++ > > > tests/qtest/libqos/virtio-blk.c | 14 +- > > > tests/qtest/vhost-user-test.c | 290 +++++++++++++++++++++++++++++++------ > > > 5 files changed, 322 insertions(+), 50 deletions(-) > > > > > > -- > > > 2.7.4 > >
On Tue, Sep 29, 2020 at 03:13:09AM -0400, Michael S. Tsirkin wrote: > On Sun, Sep 27, 2020 at 09:48:28AM +0300, Dima Stepanov wrote: > > On Thu, Sep 24, 2020 at 07:26:14AM -0400, Michael S. Tsirkin wrote: > > > On Fri, Sep 11, 2020 at 11:39:42AM +0300, Dima Stepanov wrote: > > > > v4 -> v5: > > > > - vhost: check queue state in the vhost_dev_set_log routine > > > > tests/qtest/vhost-user-test: prepare the tests for adding new > > > > dev class > > > > tests/qtest/vhost-user-test: add support for the > > > > vhost-user-blk device > > > > tests/qtest/vhost-user-test: add migrate_reconnect test > > > > Reviewed-by: Raphael Norwitz > > > > - Update qtest, by merging vhost-user-blk "if" case with the > > > > virtio-blk case. > > > > > > I dropped patches 3-7 since they were stalling on some systems. > > > Pls work with Peter Maydell (cc'd) to figure it out. > > Thanks! > > > > Peter, can you share any details for the stalling errors with me? > > I can say for sure that even on x86/linux the affected tests take > much longer to run with these applied. > I'd suggest making sure there are no timeouts involved in the good case .... Could you help me to reproduce it? Because on my system i see only 10+ seconds increase for the qos-test set to pass (both x86_64 and i386). So on the current master i'm running it like: - ./configure --target-list="x86_64-softmmu i386-softmmu" - with no patch set: time QTEST_QEMU_BINARY=./build/x86_64-softmmu/qemu-system-x86_64 ./build/tests/qtest/qos-test real 0m6.394s user 0m3.643s sys 0m3.477s - without patch 7 (where i include vhost-user-net tests also): real 0m9.955s user 0m4.133s sys 0m4.397s - full patch set: real 0m17.263s user 0m4.530s sys 0m4.802s For i386 target i see pretty the same numbers: time QTEST_QEMU_BINARY=./build/i386-softmmu/qemu-system-i386 ./build/tests/qtest/qos-test real 0m17.386s user 0m4.503s sys 0m4.911s So it looks like that i'm missing some step to reproduce an issue. And if i run the exact test it takes ~2-3s to pass: $ time QTEST_QEMU_BINARY=./build/x86_64-softmmu/qemu-system-x86_64 ./build/tests/qtest/qos-test -p /x86_64/pc/i440FX-pcihost/pci-bus-pc/pci-bus/vhost-user-blk-pci/vhost-user-blk/vhost-user-blk-tests/reconnect /x86_64/pc/i440FX-pcihost/pci-bus-pc/pci-bus/vhost-user-blk-pci/vhost-user-blk/vhost-user-blk-tests/reconnect: OK real 0m2.253s user 0m0.118s sys 0m0.104s And same numbers for i386. > > > > > > > > > > > v3 -> v4: > > > > - vhost: recheck dev state in the vhost_migration_log routine > > > > Reviewed-by: Raphael Norwitz > > > > - vhost: check queue state in the vhost_dev_set_log routine > > > > Use "continue" instead of "break" to handle non-initialized > > > > virtqueue case. > > > > > > > > v2 -> v3: > > > > - update commit message for the > > > > "vhost: recheck dev state in the vhost_migration_log routine" commit > > > > - rename "started" field of the VhostUserBlk structure to > > > > "started_vu", so there will be no confustion with the VHOST started > > > > field > > > > - update vhost-user-test.c to always initialize nq local variable > > > > (spotted by patchew) > > > > > > > > v1 -> v2: > > > > - add comments to connected/started fields in the header file > > > > - move the "s->started" logic from the vhost_user_blk_disconnect > > > > routine to the vhost_user_blk_stop routine > > > > > > > > Reference e-mail threads: > > > > - https://lists.gnu.org/archive/html/qemu-devel/2020-05/msg01509.html > > > > - https://lists.gnu.org/archive/html/qemu-devel/2020-05/msg05241.html > > > > > > > > If vhost-user daemon is used as a backend for the vhost device, then we > > > > should consider a possibility of disconnect at any moment. There was a general > > > > question here: should we consider it as an error or okay state for the vhost-user > > > > devices during migration process? > > > > I think the disconnect event for the vhost-user devices should not break the > > > > migration process, because: > > > > - the device will be in the stopped state, so it will not be changed > > > > during migration > > > > - if reconnect will be made the migration log will be reinitialized as > > > > part of reconnect/init process: > > > > #0 vhost_log_global_start (listener=0x563989cf7be0) > > > > at hw/virtio/vhost.c:920 > > > > #1 0x000056398603d8bc in listener_add_address_space (listener=0x563989cf7be0, > > > > as=0x563986ea4340 <address_space_memory>) > > > > at softmmu/memory.c:2664 > > > > #2 0x000056398603dd30 in memory_listener_register (listener=0x563989cf7be0, > > > > as=0x563986ea4340 <address_space_memory>) > > > > at softmmu/memory.c:2740 > > > > #3 0x0000563985fd6956 in vhost_dev_init (hdev=0x563989cf7bd8, > > > > opaque=0x563989cf7e30, backend_type=VHOST_BACKEND_TYPE_USER, > > > > busyloop_timeout=0) > > > > at hw/virtio/vhost.c:1385 > > > > #4 0x0000563985f7d0b8 in vhost_user_blk_connect (dev=0x563989cf7990) > > > > at hw/block/vhost-user-blk.c:315 > > > > #5 0x0000563985f7d3f6 in vhost_user_blk_event (opaque=0x563989cf7990, > > > > event=CHR_EVENT_OPENED) > > > > at hw/block/vhost-user-blk.c:379 > > > > The first patch in the patchset fixes this issue by setting vhost device to the > > > > stopped state in the disconnect handler and check it the vhost_migration_log() > > > > routine before returning from the function. > > > > qtest framework was updated to test vhost-user-blk functionality. The > > > > vhost-user-blk/vhost-user-blk-tests/migrate_reconnect test was added to reproduce > > > > the original issue found. > > > > > > > > Dima Stepanov (7): > > > > vhost: recheck dev state in the vhost_migration_log routine > > > > vhost: check queue state in the vhost_dev_set_log routine > > > > tests/qtest/vhost-user-test: prepare the tests for adding new dev > > > > class > > > > tests/qtest/libqos/virtio-blk: add support for vhost-user-blk > > > > tests/qtest/vhost-user-test: add support for the vhost-user-blk device > > > > tests/qtest/vhost-user-test: add migrate_reconnect test > > > > tests/qtest/vhost-user-test: enable the reconnect tests > > > > > > > > hw/block/vhost-user-blk.c | 19 ++- > > > > hw/virtio/vhost.c | 39 ++++- > > > > include/hw/virtio/vhost-user-blk.h | 10 ++ > > > > tests/qtest/libqos/virtio-blk.c | 14 +- > > > > tests/qtest/vhost-user-test.c | 290 +++++++++++++++++++++++++++++++------ > > > > 5 files changed, 322 insertions(+), 50 deletions(-) > > > > > > > > -- > > > > 2.7.4 > > > >
On Tue, Sep 29, 2020 at 12:48:38PM +0300, Dima Stepanov wrote: > On Tue, Sep 29, 2020 at 03:13:09AM -0400, Michael S. Tsirkin wrote: > > On Sun, Sep 27, 2020 at 09:48:28AM +0300, Dima Stepanov wrote: > > > On Thu, Sep 24, 2020 at 07:26:14AM -0400, Michael S. Tsirkin wrote: > > > > On Fri, Sep 11, 2020 at 11:39:42AM +0300, Dima Stepanov wrote: > > > > > v4 -> v5: > > > > > - vhost: check queue state in the vhost_dev_set_log routine > > > > > tests/qtest/vhost-user-test: prepare the tests for adding new > > > > > dev class > > > > > tests/qtest/vhost-user-test: add support for the > > > > > vhost-user-blk device > > > > > tests/qtest/vhost-user-test: add migrate_reconnect test > > > > > Reviewed-by: Raphael Norwitz > > > > > - Update qtest, by merging vhost-user-blk "if" case with the > > > > > virtio-blk case. > > > > > > > > I dropped patches 3-7 since they were stalling on some systems. > > > > Pls work with Peter Maydell (cc'd) to figure it out. > > > Thanks! > > > > > > Peter, can you share any details for the stalling errors with me? > > > > I can say for sure that even on x86/linux the affected tests take > > much longer to run with these applied. > > I'd suggest making sure there are no timeouts involved in the good case .... > Could you help me to reproduce it? Because on my system i see only 10+ seconds > increase for the qos-test set to pass (both x86_64 and i386). So on the > current master i'm running it like: > - ./configure --target-list="x86_64-softmmu i386-softmmu" > - with no patch set: > time QTEST_QEMU_BINARY=./build/x86_64-softmmu/qemu-system-x86_64 ./build/tests/qtest/qos-test > real 0m6.394s > user 0m3.643s > sys 0m3.477s > - without patch 7 (where i include vhost-user-net tests also): > real 0m9.955s > user 0m4.133s > sys 0m4.397s > - full patch set: > real 0m17.263s > user 0m4.530s > sys 0m4.802s > For i386 target i see pretty the same numbers: > time QTEST_QEMU_BINARY=./build/i386-softmmu/qemu-system-i386 ./build/tests/qtest/qos-test > real 0m17.386s > user 0m4.503s > sys 0m4.911s > So it looks like that i'm missing some step to reproduce an issue. > > And if i run the exact test it takes ~2-3s to pass: > $ time QTEST_QEMU_BINARY=./build/x86_64-softmmu/qemu-system-x86_64 ./build/tests/qtest/qos-test -p /x86_64/pc/i440FX-pcihost/pci-bus-pc/pci-bus/vhost-user-blk-pci/vhost-user-blk/vhost-user-blk-tests/reconnect > /x86_64/pc/i440FX-pcihost/pci-bus-pc/pci-bus/vhost-user-blk-pci/vhost-user-blk/vhost-user-blk-tests/reconnect: OK > real 0m2.253s > user 0m0.118s > sys 0m0.104s > And same numbers for i386. > Sorry, but still fail to reproduce the stall issue on both i386 and x86_64 targets. Any help is highly appreciated. Thanks, Dima. > > > > > > > > > > > > > > > v3 -> v4: > > > > > - vhost: recheck dev state in the vhost_migration_log routine > > > > > Reviewed-by: Raphael Norwitz > > > > > - vhost: check queue state in the vhost_dev_set_log routine > > > > > Use "continue" instead of "break" to handle non-initialized > > > > > virtqueue case. > > > > > > > > > > v2 -> v3: > > > > > - update commit message for the > > > > > "vhost: recheck dev state in the vhost_migration_log routine" commit > > > > > - rename "started" field of the VhostUserBlk structure to > > > > > "started_vu", so there will be no confustion with the VHOST started > > > > > field > > > > > - update vhost-user-test.c to always initialize nq local variable > > > > > (spotted by patchew) > > > > > > > > > > v1 -> v2: > > > > > - add comments to connected/started fields in the header file > > > > > - move the "s->started" logic from the vhost_user_blk_disconnect > > > > > routine to the vhost_user_blk_stop routine > > > > > > > > > > Reference e-mail threads: > > > > > - https://lists.gnu.org/archive/html/qemu-devel/2020-05/msg01509.html > > > > > - https://lists.gnu.org/archive/html/qemu-devel/2020-05/msg05241.html > > > > > > > > > > If vhost-user daemon is used as a backend for the vhost device, then we > > > > > should consider a possibility of disconnect at any moment. There was a general > > > > > question here: should we consider it as an error or okay state for the vhost-user > > > > > devices during migration process? > > > > > I think the disconnect event for the vhost-user devices should not break the > > > > > migration process, because: > > > > > - the device will be in the stopped state, so it will not be changed > > > > > during migration > > > > > - if reconnect will be made the migration log will be reinitialized as > > > > > part of reconnect/init process: > > > > > #0 vhost_log_global_start (listener=0x563989cf7be0) > > > > > at hw/virtio/vhost.c:920 > > > > > #1 0x000056398603d8bc in listener_add_address_space (listener=0x563989cf7be0, > > > > > as=0x563986ea4340 <address_space_memory>) > > > > > at softmmu/memory.c:2664 > > > > > #2 0x000056398603dd30 in memory_listener_register (listener=0x563989cf7be0, > > > > > as=0x563986ea4340 <address_space_memory>) > > > > > at softmmu/memory.c:2740 > > > > > #3 0x0000563985fd6956 in vhost_dev_init (hdev=0x563989cf7bd8, > > > > > opaque=0x563989cf7e30, backend_type=VHOST_BACKEND_TYPE_USER, > > > > > busyloop_timeout=0) > > > > > at hw/virtio/vhost.c:1385 > > > > > #4 0x0000563985f7d0b8 in vhost_user_blk_connect (dev=0x563989cf7990) > > > > > at hw/block/vhost-user-blk.c:315 > > > > > #5 0x0000563985f7d3f6 in vhost_user_blk_event (opaque=0x563989cf7990, > > > > > event=CHR_EVENT_OPENED) > > > > > at hw/block/vhost-user-blk.c:379 > > > > > The first patch in the patchset fixes this issue by setting vhost device to the > > > > > stopped state in the disconnect handler and check it the vhost_migration_log() > > > > > routine before returning from the function. > > > > > qtest framework was updated to test vhost-user-blk functionality. The > > > > > vhost-user-blk/vhost-user-blk-tests/migrate_reconnect test was added to reproduce > > > > > the original issue found. > > > > > > > > > > Dima Stepanov (7): > > > > > vhost: recheck dev state in the vhost_migration_log routine > > > > > vhost: check queue state in the vhost_dev_set_log routine > > > > > tests/qtest/vhost-user-test: prepare the tests for adding new dev > > > > > class > > > > > tests/qtest/libqos/virtio-blk: add support for vhost-user-blk > > > > > tests/qtest/vhost-user-test: add support for the vhost-user-blk device > > > > > tests/qtest/vhost-user-test: add migrate_reconnect test > > > > > tests/qtest/vhost-user-test: enable the reconnect tests > > > > > > > > > > hw/block/vhost-user-blk.c | 19 ++- > > > > > hw/virtio/vhost.c | 39 ++++- > > > > > include/hw/virtio/vhost-user-blk.h | 10 ++ > > > > > tests/qtest/libqos/virtio-blk.c | 14 +- > > > > > tests/qtest/vhost-user-test.c | 290 +++++++++++++++++++++++++++++++------ > > > > > 5 files changed, 322 insertions(+), 50 deletions(-) > > > > > > > > > > -- > > > > > 2.7.4 > > > > > >
v4 -> v5: - vhost: check queue state in the vhost_dev_set_log routine tests/qtest/vhost-user-test: prepare the tests for adding new dev class tests/qtest/vhost-user-test: add support for the vhost-user-blk device tests/qtest/vhost-user-test: add migrate_reconnect test Reviewed-by: Raphael Norwitz - Update qtest, by merging vhost-user-blk "if" case with the virtio-blk case. v3 -> v4: - vhost: recheck dev state in the vhost_migration_log routine Reviewed-by: Raphael Norwitz - vhost: check queue state in the vhost_dev_set_log routine Use "continue" instead of "break" to handle non-initialized virtqueue case. v2 -> v3: - update commit message for the "vhost: recheck dev state in the vhost_migration_log routine" commit - rename "started" field of the VhostUserBlk structure to "started_vu", so there will be no confustion with the VHOST started field - update vhost-user-test.c to always initialize nq local variable (spotted by patchew) v1 -> v2: - add comments to connected/started fields in the header file - move the "s->started" logic from the vhost_user_blk_disconnect routine to the vhost_user_blk_stop routine Reference e-mail threads: - https://lists.gnu.org/archive/html/qemu-devel/2020-05/msg01509.html - https://lists.gnu.org/archive/html/qemu-devel/2020-05/msg05241.html If vhost-user daemon is used as a backend for the vhost device, then we should consider a possibility of disconnect at any moment. There was a general question here: should we consider it as an error or okay state for the vhost-user devices during migration process? I think the disconnect event for the vhost-user devices should not break the migration process, because: - the device will be in the stopped state, so it will not be changed during migration - if reconnect will be made the migration log will be reinitialized as part of reconnect/init process: #0 vhost_log_global_start (listener=0x563989cf7be0) at hw/virtio/vhost.c:920 #1 0x000056398603d8bc in listener_add_address_space (listener=0x563989cf7be0, as=0x563986ea4340 <address_space_memory>) at softmmu/memory.c:2664 #2 0x000056398603dd30 in memory_listener_register (listener=0x563989cf7be0, as=0x563986ea4340 <address_space_memory>) at softmmu/memory.c:2740 #3 0x0000563985fd6956 in vhost_dev_init (hdev=0x563989cf7bd8, opaque=0x563989cf7e30, backend_type=VHOST_BACKEND_TYPE_USER, busyloop_timeout=0) at hw/virtio/vhost.c:1385 #4 0x0000563985f7d0b8 in vhost_user_blk_connect (dev=0x563989cf7990) at hw/block/vhost-user-blk.c:315 #5 0x0000563985f7d3f6 in vhost_user_blk_event (opaque=0x563989cf7990, event=CHR_EVENT_OPENED) at hw/block/vhost-user-blk.c:379 The first patch in the patchset fixes this issue by setting vhost device to the stopped state in the disconnect handler and check it the vhost_migration_log() routine before returning from the function. qtest framework was updated to test vhost-user-blk functionality. The vhost-user-blk/vhost-user-blk-tests/migrate_reconnect test was added to reproduce the original issue found. Dima Stepanov (7): vhost: recheck dev state in the vhost_migration_log routine vhost: check queue state in the vhost_dev_set_log routine tests/qtest/vhost-user-test: prepare the tests for adding new dev class tests/qtest/libqos/virtio-blk: add support for vhost-user-blk tests/qtest/vhost-user-test: add support for the vhost-user-blk device tests/qtest/vhost-user-test: add migrate_reconnect test tests/qtest/vhost-user-test: enable the reconnect tests hw/block/vhost-user-blk.c | 19 ++- hw/virtio/vhost.c | 39 ++++- include/hw/virtio/vhost-user-blk.h | 10 ++ tests/qtest/libqos/virtio-blk.c | 14 +- tests/qtest/vhost-user-test.c | 290 +++++++++++++++++++++++++++++++------ 5 files changed, 322 insertions(+), 50 deletions(-)