[PATCH 14/17] lustre/ptlrpc: re-enqueue ptlrpcd worker
From: Liang Zhen
osc_extent_wait can be stuck in scenario like this:
1) thread-1 held an active extent
2) thread-2 called flush cache, and marked this extent as "urgent"
and "sync_wait"
3) thread-3 wants to write to the same extent, osc_extent_find will
get "conflict" because this extent is "sync_wait", so it starts
to wait...
4) cl_writeback_work has been scheduled by thread-4 to write some
other extents, it has sent RPCs but not returned yet.
5) thread-1 finished his work, and called osc_extent_release()->
osc_io_unplug_async()->ptlrpcd_queue_work(), but found
cl_writeback_work is still running, so it's ignored (-EBUSY)
6) thread-3 is stuck because nobody will wake him up.
This patch allows ptlrpcd_work to be rescheduled, so it will not
miss request anymore
Signed-off-by: Liang Zhen
Reviewed-on: http://review.whamcloud.com/8922
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4509
Reviewed-by: Jinshan Xiong
Reviewed-by: Bobi Jam
Reviewed-by: Oleg Drokin
Signed-off-by: Oleg Drokin
---
drivers/staging/lustre/lustre/ptlrpc/client.c | 64 +--
1 file changed, 40 insertions(+), 24 deletions(-)
diff --git a/drivers/staging/lustre/lustre/ptlrpc/client.c
b/drivers/staging/lustre/lustre/ptlrpc/client.c
index 7b97c64..4c9e006 100644
--- a/drivers/staging/lustre/lustre/ptlrpc/client.c
+++ b/drivers/staging/lustre/lustre/ptlrpc/client.c
@@ -48,6 +48,7 @@
#include "ptlrpc_internal.h"
static int ptlrpc_send_new_req(struct ptlrpc_request *req);
+static int ptlrpcd_check_work(struct ptlrpc_request *req);
/**
* Initialize passed in client structure \a cl.
@@ -1784,6 +1785,10 @@ interpret:
ptlrpc_req_interpret(env, req, req->rq_status);
+ if (ptlrpcd_check_work(req)) {
+ atomic_dec(>set_remaining);
+ continue;
+ }
ptlrpc_rqphase_move(req, RQ_PHASE_COMPLETE);
CDEBUG(req->rq_reqmsg != NULL ? D_RPCTRACE : 0,
@@ -2957,22 +2962,50 @@ EXPORT_SYMBOL(ptlrpc_sample_next_xid);
*have delay before it really runs by ptlrpcd thread.
*/
struct ptlrpc_work_async_args {
- __u64 magic;
int (*cb)(const struct lu_env *, void *);
void *cbdata;
};
-#define PTLRPC_WORK_MAGIC 0x6655436b676f4f44ULL /* magic code */
+static void ptlrpcd_add_work_req(struct ptlrpc_request *req)
+{
+ /* re-initialize the req */
+ req->rq_timeout = obd_timeout;
+ req->rq_sent= cfs_time_current_sec();
+ req->rq_deadline= req->rq_sent + req->rq_timeout;
+ req->rq_reply_deadline = req->rq_deadline;
+ req->rq_phase = RQ_PHASE_INTERPRET;
+ req->rq_next_phase = RQ_PHASE_COMPLETE;
+ req->rq_xid = ptlrpc_next_xid();
+ req->rq_import_generation = req->rq_import->imp_generation;
+
+ ptlrpcd_add_req(req, PDL_POLICY_ROUND, -1);
+}
static int work_interpreter(const struct lu_env *env,
struct ptlrpc_request *req, void *data, int rc)
{
struct ptlrpc_work_async_args *arg = data;
- LASSERT(arg->magic == PTLRPC_WORK_MAGIC);
+ LASSERT(ptlrpcd_check_work(req));
LASSERT(arg->cb != NULL);
- return arg->cb(env, arg->cbdata);
+ rc = arg->cb(env, arg->cbdata);
+
+ list_del_init(>rq_set_chain);
+ req->rq_set = NULL;
+
+ if (atomic_dec_return(>rq_refcount) > 1) {
+ atomic_set(>rq_refcount, 2);
+ ptlrpcd_add_work_req(req);
+ }
+ return rc;
+}
+
+static int worker_format;
+
+static int ptlrpcd_check_work(struct ptlrpc_request *req)
+{
+ return req->rq_pill.rc_fmt == (void *)_format;
}
/**
@@ -3005,6 +3038,7 @@ void *ptlrpcd_alloc_work(struct obd_import *imp,
req->rq_receiving_reply = 0;
req->rq_must_unlink = 0;
req->rq_no_delay = req->rq_no_resend = 1;
+ req->rq_pill.rc_fmt = (void *)_format;
spin_lock_init(>rq_lock);
INIT_LIST_HEAD(>rq_list);
@@ -3018,7 +3052,6 @@ void *ptlrpcd_alloc_work(struct obd_import *imp,
CLASSERT(sizeof(*args) <= sizeof(req->rq_async_args));
args = ptlrpc_req_async_args(req);
- args->magic = PTLRPC_WORK_MAGIC;
args->cb = cb;
args->cbdata = cbdata;
@@ -3048,25 +3081,8 @@ int ptlrpcd_queue_work(void *handler)
* req as opaque data. - Jinshan
*/
LASSERT(atomic_read(>rq_refcount) > 0);
- if (atomic_read(>rq_refcount) > 1)
- return -EBUSY;
-
- if (atomic_inc_return(>rq_refcount) > 2) { /* race */
- atomic_dec(>rq_refcount);
- return -EBUSY;
- }
-
- /* re-initialize the req */
- req->rq_timeout = obd_timeout;
- req->rq_sent = cfs_time_current_sec();
- req->rq_deadline = req->rq_sent + req->rq_timeout;
- req->rq_reply_deadline = req->rq_deadline;
- req->rq_phase =
[PATCH 14/17] lustre/ptlrpc: re-enqueue ptlrpcd worker
From: Liang Zhen liang.z...@intel.com
osc_extent_wait can be stuck in scenario like this:
1) thread-1 held an active extent
2) thread-2 called flush cache, and marked this extent as urgent
and sync_wait
3) thread-3 wants to write to the same extent, osc_extent_find will
get conflict because this extent is sync_wait, so it starts
to wait...
4) cl_writeback_work has been scheduled by thread-4 to write some
other extents, it has sent RPCs but not returned yet.
5) thread-1 finished his work, and called osc_extent_release()-
osc_io_unplug_async()-ptlrpcd_queue_work(), but found
cl_writeback_work is still running, so it's ignored (-EBUSY)
6) thread-3 is stuck because nobody will wake him up.
This patch allows ptlrpcd_work to be rescheduled, so it will not
miss request anymore
Signed-off-by: Liang Zhen liang.z...@intel.com
Reviewed-on: http://review.whamcloud.com/8922
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4509
Reviewed-by: Jinshan Xiong jinshan.xi...@intel.com
Reviewed-by: Bobi Jam bobi...@gmail.com
Reviewed-by: Oleg Drokin oleg.dro...@intel.com
Signed-off-by: Oleg Drokin oleg.dro...@intel.com
---
drivers/staging/lustre/lustre/ptlrpc/client.c | 64 +--
1 file changed, 40 insertions(+), 24 deletions(-)
diff --git a/drivers/staging/lustre/lustre/ptlrpc/client.c
b/drivers/staging/lustre/lustre/ptlrpc/client.c
index 7b97c64..4c9e006 100644
--- a/drivers/staging/lustre/lustre/ptlrpc/client.c
+++ b/drivers/staging/lustre/lustre/ptlrpc/client.c
@@ -48,6 +48,7 @@
#include ptlrpc_internal.h
static int ptlrpc_send_new_req(struct ptlrpc_request *req);
+static int ptlrpcd_check_work(struct ptlrpc_request *req);
/**
* Initialize passed in client structure \a cl.
@@ -1784,6 +1785,10 @@ interpret:
ptlrpc_req_interpret(env, req, req-rq_status);
+ if (ptlrpcd_check_work(req)) {
+ atomic_dec(set-set_remaining);
+ continue;
+ }
ptlrpc_rqphase_move(req, RQ_PHASE_COMPLETE);
CDEBUG(req-rq_reqmsg != NULL ? D_RPCTRACE : 0,
@@ -2957,22 +2962,50 @@ EXPORT_SYMBOL(ptlrpc_sample_next_xid);
*have delay before it really runs by ptlrpcd thread.
*/
struct ptlrpc_work_async_args {
- __u64 magic;
int (*cb)(const struct lu_env *, void *);
void *cbdata;
};
-#define PTLRPC_WORK_MAGIC 0x6655436b676f4f44ULL /* magic code */
+static void ptlrpcd_add_work_req(struct ptlrpc_request *req)
+{
+ /* re-initialize the req */
+ req-rq_timeout = obd_timeout;
+ req-rq_sent= cfs_time_current_sec();
+ req-rq_deadline= req-rq_sent + req-rq_timeout;
+ req-rq_reply_deadline = req-rq_deadline;
+ req-rq_phase = RQ_PHASE_INTERPRET;
+ req-rq_next_phase = RQ_PHASE_COMPLETE;
+ req-rq_xid = ptlrpc_next_xid();
+ req-rq_import_generation = req-rq_import-imp_generation;
+
+ ptlrpcd_add_req(req, PDL_POLICY_ROUND, -1);
+}
static int work_interpreter(const struct lu_env *env,
struct ptlrpc_request *req, void *data, int rc)
{
struct ptlrpc_work_async_args *arg = data;
- LASSERT(arg-magic == PTLRPC_WORK_MAGIC);
+ LASSERT(ptlrpcd_check_work(req));
LASSERT(arg-cb != NULL);
- return arg-cb(env, arg-cbdata);
+ rc = arg-cb(env, arg-cbdata);
+
+ list_del_init(req-rq_set_chain);
+ req-rq_set = NULL;
+
+ if (atomic_dec_return(req-rq_refcount) 1) {
+ atomic_set(req-rq_refcount, 2);
+ ptlrpcd_add_work_req(req);
+ }
+ return rc;
+}
+
+static int worker_format;
+
+static int ptlrpcd_check_work(struct ptlrpc_request *req)
+{
+ return req-rq_pill.rc_fmt == (void *)worker_format;
}
/**
@@ -3005,6 +3038,7 @@ void *ptlrpcd_alloc_work(struct obd_import *imp,
req-rq_receiving_reply = 0;
req-rq_must_unlink = 0;
req-rq_no_delay = req-rq_no_resend = 1;
+ req-rq_pill.rc_fmt = (void *)worker_format;
spin_lock_init(req-rq_lock);
INIT_LIST_HEAD(req-rq_list);
@@ -3018,7 +3052,6 @@ void *ptlrpcd_alloc_work(struct obd_import *imp,
CLASSERT(sizeof(*args) = sizeof(req-rq_async_args));
args = ptlrpc_req_async_args(req);
- args-magic = PTLRPC_WORK_MAGIC;
args-cb = cb;
args-cbdata = cbdata;
@@ -3048,25 +3081,8 @@ int ptlrpcd_queue_work(void *handler)
* req as opaque data. - Jinshan
*/
LASSERT(atomic_read(req-rq_refcount) 0);
- if (atomic_read(req-rq_refcount) 1)
- return -EBUSY;
-
- if (atomic_inc_return(req-rq_refcount) 2) { /* race */
- atomic_dec(req-rq_refcount);
- return -EBUSY;
- }
-
- /* re-initialize the req */
- req-rq_timeout = obd_timeout;
- req-rq_sent = cfs_time_current_sec();
- req-rq_deadline =
