[Devel] [PATCH 1/3] fs/fuse kio: fix loss of FUSE_FSYNC/FUSE_FLUSH reqs

[Pavel Butsykin]

sorry, Not there XD

pls, don't ignore this.

On 03.12.2018 16:04, Pavel Butsykin wrote:
> pls ignore this.
> 
> On 03.12.2018 16:02, Pavel Butsykin wrote:
>> Fast-Path can loss fsync/flush requests, because PCS_REQ_T_SYNC 
>> request set up
>> PCS_MAP_FLUSHING flag, but never cleans it. Although initially 
>> PCS_MAP_FLUSHING
>> flag was created for sync timer, so PCS_REQ_T_SYNC request should ignore
>> everything related to PCS_REQ_T_SYNC flag.
>>
>> This patch adds timer_sync flag in prepare_map_flush_ireq() to ignore 
>> all sync
>> timer stuff on PCS_REQ_T_SYNC way.
>>
>> Signed-off-by: Pavel Butsykin <pbutsykin at virtuozzo.com>
>> ---
>>   fs/fuse/kio/pcs/pcs_map.c | 27 ++++++++++++++++-----------
>>   1 file changed, 16 insertions(+), 11 deletions(-)
>>
>> diff --git a/fs/fuse/kio/pcs/pcs_map.c b/fs/fuse/kio/pcs/pcs_map.c
>> index 459645417462..4bd18c5224ab 100644
>> --- a/fs/fuse/kio/pcs/pcs_map.c
>> +++ b/fs/fuse/kio/pcs/pcs_map.c
>> @@ -2959,20 +2959,24 @@ static void prepare_map_flush_msg(struct 
>> pcs_map_entry * m, struct pcs_int_reque
>>       msg->done = sync_done;
>>   }
>> -static bool valid_for_flush(struct pcs_map_entry *m)
>> +static bool valid_for_flush(struct pcs_map_entry *m, bool timer_sync)
>>   {
>> -    if (m->state & PCS_MAP_DEAD)
>> -        return false;
>> +    if (timer_sync) {
>> +        if (m->state & PCS_MAP_DEAD)
>> +            return false;
>> +        if (m->flags & PCS_MAP_FLUSHING)
>> +            return false;
>> +    }
>>       if (!(m->flags & PCS_MAP_DIRTY))
>>           return false;
>> -    if (m->flags & PCS_MAP_FLUSHING)
>> -        return false;
>>       return true;
>>   }
>> -static int prepare_map_flush_ireq(struct pcs_map_entry *m, struct 
>> pcs_int_request **sreqp)
>> +static int prepare_map_flush_ireq(struct pcs_map_entry *m,
>> +                  struct pcs_int_request **sreqp,
>> +                  bool timer_sync)
>>   {
>>       struct pcs_dentry_info *de;
>>       struct pcs_cs_list *cslist;
>> @@ -2980,7 +2984,7 @@ static int prepare_map_flush_ireq(struct 
>> pcs_map_entry *m, struct pcs_int_reques
>>       struct pcs_msg * msg;
>>       spin_lock(&m->lock);
>> -    if (!valid_for_flush(m)) {
>> +    if (!valid_for_flush(m, timer_sync)) {
>>           spin_unlock(&m->lock);
>>           return 0;
>>       }
>> @@ -3010,7 +3014,7 @@ static int prepare_map_flush_ireq(struct 
>> pcs_map_entry *m, struct pcs_int_reques
>>       /* All resources allocated, we need to recheck maps state again */
>>       spin_lock(&m->lock);
>>       cslist_put(cslist);
>> -    if (!valid_for_flush(m) || m->cs_list != cslist) {
>> +    if (!valid_for_flush(m, timer_sync) || m->cs_list != cslist) {
>>           spin_unlock(&m->lock);
>>           return 0;
>>       }
>> @@ -3025,7 +3029,8 @@ static int prepare_map_flush_ireq(struct 
>> pcs_map_entry *m, struct pcs_int_reques
>>       sreq->complete_cb = pcs_flushreq_complete;
>>       sreq->flushreq.msg = msg;
>>       FUSE_KTRACE(sreq->cc->fc, "timed FLUSH " MAP_FMT, MAP_ARGS(m));
>> -    m->flags |= PCS_MAP_FLUSHING;
>> +    if (timer_sync)
>> +        m->flags |= PCS_MAP_FLUSHING;
>>       __pcs_map_get(m);
>>       spin_unlock(&m->lock);
>>       *sreqp    = sreq;
>> @@ -3047,7 +3052,7 @@ static void sync_timer_work(struct work_struct *w)
>>       struct pcs_int_request * sreq = NULL;
>>       int err;
>> -    err = prepare_map_flush_ireq(m, &sreq);
>> +    err = prepare_map_flush_ireq(m, &sreq, true);
>>       if (err) {
>>           spin_lock(&m->lock);
>>           if (!(m->state & PCS_MAP_DEAD))
>> @@ -3125,7 +3130,7 @@ void map_inject_flush_req(struct pcs_int_request 
>> *ireq)
>>                   break;
>>               if (!maps[i])
>>                   continue;
>> -            err = prepare_map_flush_ireq(maps[i], &sreq);
>> +            err = prepare_map_flush_ireq(maps[i], &sreq, false);
>>               pcs_map_put(maps[i]);
>>               if (err) {
>>                   pcs_set_local_error(&ireq->error, PCS_ERR_NOMEM);
>>