On 08/27/2018 08:04 AM, Yi Wang wrote:

When doing some job holding state lock for a long time, we may come across error: "Timed out during operation: cannot acquire state change lock" Well, sometimes it's not a problem and users wanner continue to wait, and this patch allow users decide how long time they can wait the state lock.

Signed-off-by: Yi Wang <wang.yi59@zte.com.cn> Reviewed-by: Xi Xu <xu.xi8@zte.com.cn> --- src/qemu/libvirtd_qemu.aug | 1 + src/qemu/qemu.conf | 6 ++++++ src/qemu/qemu_conf.c | 3 +++ src/qemu/qemu_conf.h | 2 ++ src/qemu/qemu_domain.c | 6 +++++- src/qemu/test_libvirtd_qemu.aug.in | 1 + 6 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/src/qemu/libvirtd_qemu.aug b/src/qemu/libvirtd_qemu.aug index ddc4bbf..f7287ae 100644 --- a/src/qemu/libvirtd_qemu.aug +++ b/src/qemu/libvirtd_qemu.aug @@ -93,6 +93,7 @@ module Libvirtd_qemu = | limits_entry "max_core" | bool_entry "dump_guest_core" | str_entry "stdio_handler" + | int_entry "state_lock_timeout"

let device_entry = bool_entry "mac_filter" | bool_entry "relaxed_acs_check" diff --git a/src/qemu/qemu.conf b/src/qemu/qemu.conf index cd57b3c..e88db3f 100644 --- a/src/qemu/qemu.conf +++ b/src/qemu/qemu.conf @@ -813,3 +813,9 @@ # #swtpm_user = "tss" #swtpm_group = "tss" + +# Override the timeout (in seconds) for acquiring state lock. +# +# Default is 0 +# +#state_lock_timeout = 60

Firstly, the default value should be set for the variable. So if the default is really 0 (which it is not) then this line should read: #state_lock_timeout = 0 Secondly, the default is not zero, because if user sets it to zero your code uses the hardcoded timeout of 30 seconds. Also, we should probably reserve 0 for some special future use (no timeouts perhaps?)

diff --git a/src/qemu/qemu_conf.c b/src/qemu/qemu_conf.c index a4f545e..f452714 100644 --- a/src/qemu/qemu_conf.c +++ b/src/qemu/qemu_conf.c @@ -863,6 +863,9 @@ int virQEMUDriverConfigLoadFile(virQEMUDriverConfigPtr cfg, if (virConfGetValueUInt(conf, "keepalive_count", &cfg->keepAliveCount) < 0) goto cleanup;

+ if (virConfGetValueInt(conf, "state_lock_timeout", &cfg->stateLockTimeout) < 0) + goto cleanup; + if (virConfGetValueInt(conf, "seccomp_sandbox", &cfg->seccompSandbox) < 0) goto cleanup;

diff --git a/src/qemu/qemu_conf.h b/src/qemu/qemu_conf.h index a8d84ef..97cf2e1 100644 --- a/src/qemu/qemu_conf.h +++ b/src/qemu/qemu_conf.h @@ -190,6 +190,8 @@ struct _virQEMUDriverConfig { int keepAliveInterval; unsigned int keepAliveCount;

+ int stateLockTimeout; + int seccompSandbox;

char *migrateHost; diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c index 886e3fb..d375a73 100644 --- a/src/qemu/qemu_domain.c +++ b/src/qemu/qemu_domain.c @@ -6714,7 +6714,11 @@ qemuDomainObjBeginJobInternal(virQEMUDriverPtr driver, }

priv->jobs_queued++; - then = now + QEMU_JOB_WAIT_TIME; + if (cfg->stateLockTimeout > 0) + then = now + cfg->stateLockTimeout; + else + then = now + QEMU_JOB_WAIT_TIME;

You can set the default in virQEMUDriverConfigNew() so that it's always set and simplify this line then.

+

retry: if ((!async && job != QEMU_JOB_DESTROY) && diff --git a/src/qemu/test_libvirtd_qemu.aug.in b/src/qemu/test_libvirtd_qemu.aug.in index f1e8806..dc5de96 100644 --- a/src/qemu/test_libvirtd_qemu.aug.in +++ b/src/qemu/test_libvirtd_qemu.aug.in @@ -105,3 +105,4 @@ module Test_libvirtd_qemu = { "pr_helper" = "/usr/bin/qemu-pr-helper" } { "swtpm_user" = "tss" } { "swtpm_group" = "tss" } +{ "state_lock_timeout" = "60" }

Michal