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| author | Mike Christie <mchristi@redhat.com> | 2017-03-29 00:19:24 -0500 |
|---|---|---|
| committer | Nicholas Bellinger <nab@linux-iscsi.org> | 2017-03-30 23:12:40 -0700 |
| commit | d19c4643a52f0a56a7ccc86b145f207a57f40116 (patch) | |
| tree | 869b8ea9d02571f9fdd7b62902aafd22a28d6d27 /include | |
| parent | 7a56dc8888be23f44158a85b92da45d545cbf548 (diff) | |
| download | linux-d19c4643a52f0a56a7ccc86b145f207a57f40116.tar.gz linux-d19c4643a52f0a56a7ccc86b145f207a57f40116.tar.bz2 linux-d19c4643a52f0a56a7ccc86b145f207a57f40116.zip | |
target: Fix ALUA transition state race between multiple initiators
Multiple threads could be writing to alua_access_state at
the same time, or there could be multiple STPGs in flight
(different initiators sending them or one initiator sending
them to different ports), or a combo of both and the
core_alua_do_transition_tg_pt calls will race with each other.
Because from the last patches we no longer delay running
core_alua_do_transition_tg_pt_work, there does not seem to be
any point in running that in a workqueue. And, we always
wait for it to complete one way or another, so we can sleep
in this code path. So, this patch made over target-pending just adds a
mutex and does the work core_alua_do_transition_tg_pt_work was doing in
core_alua_do_transition_tg_pt.
There is also no need to use an atomic for the
tg_pt_gp_alua_access_state. In core_alua_do_transition_tg_pt we will
test and set it under the transition mutex. And, it is a int/32 bits
so in the other places where it is read, we will never see it partially
updated.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/target/target_core_base.h | 8 |
1 files changed, 2 insertions, 6 deletions
diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h index 730ed3055336..ccfad0e9c2cd 100644 --- a/include/target/target_core_base.h +++ b/include/target/target_core_base.h @@ -280,8 +280,6 @@ struct t10_alua_tg_pt_gp { u16 tg_pt_gp_id; int tg_pt_gp_valid_id; int tg_pt_gp_alua_supported_states; - int tg_pt_gp_alua_pending_state; - int tg_pt_gp_alua_previous_state; int tg_pt_gp_alua_access_status; int tg_pt_gp_alua_access_type; int tg_pt_gp_nonop_delay_msecs; @@ -290,18 +288,16 @@ struct t10_alua_tg_pt_gp { int tg_pt_gp_pref; int tg_pt_gp_write_metadata; u32 tg_pt_gp_members; - atomic_t tg_pt_gp_alua_access_state; + int tg_pt_gp_alua_access_state; atomic_t tg_pt_gp_ref_cnt; spinlock_t tg_pt_gp_lock; - struct mutex tg_pt_gp_md_mutex; + struct mutex tg_pt_gp_transition_mutex; struct se_device *tg_pt_gp_dev; struct config_group tg_pt_gp_group; struct list_head tg_pt_gp_list; struct list_head tg_pt_gp_lun_list; struct se_lun *tg_pt_gp_alua_lun; struct se_node_acl *tg_pt_gp_alua_nacl; - struct work_struct tg_pt_gp_transition_work; - struct completion *tg_pt_gp_transition_complete; }; struct t10_vpd { |