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nvme: Free I/O qpair now even if it is in poll group completion

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spdk_nvme_poll_group has followed spdk_nvme_qpair about how to
process I/O qpair deletion inside of a completion context.

spdk_nvme_qpair_process_completions() accesses qpair after
returning from nvme_transport_qpair_process_completions().

So this is reasonable.

On the other hand, if spdk_nvme_poll_group_process_completions()
can execute spdk_nvme_ctrlr_free_io_qpair() inside of a completion
context, the target qpair is ensured to be deleted after returning
from spdk_nvme_ctrlr_free_io_qpair(). Then the target qpair is
not accessed anymore in spdk_nvme_poll_group_process_completions().

Remove two variables, in_completion_context and num_qpairs_to_delete,
of spdk_nvme_transport_poll_group and the related code.

This change is really necessary to support the following case.

In the NVMe bdev module, a nvme_qpair has a qpair and a poll_group
channel. disconnected_qpair_cb calls spdk_nvme_ctrlr_free_io_qpair()
for the qpair and spdk_put_io_channel() to the poll_group_channel.
spdk_nvme_ctrlr_free_io_qpair() is executed after unwinding stack
but spdk_put_io_channel() is executed now. The callback to
spdk_put_io_channel() calls spdk_nvme_poll_group_destroy(). However,
spdk_nvme_ctrlr_free_io_qpair() is not executed. Hence
spdk_nvme_poll_group_destroy() fails.

Update the corresponding stub in unit test together.

Signed-off-by: Shuhei Matsumoto <smatsumoto@nvidia.com>
Change-Id: Icd1f1daf049c6c7ffb28790fe87989a1060f8952
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/11496
Community-CI: Broadcom CI <spdk-ci.pdl@broadcom.com>
Community-CI: Mellanox Build Bot
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
This commit is contained in:
Shuhei Matsumoto 2022-02-10 10:52:59 +09:00 committed by Tomasz Zawadzki
parent c113e4cdca
commit 1285481917
4 changed files with 1 additions and 73 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
lib/nvme/nvme_ctrlr.c
View File

@ -619,13 +619,6 @@ spdk_nvme_ctrlr_free_io_qpair(struct spdk_nvme_qpair *qpair)
return 0;
}
if (qpair->poll_group && qpair->poll_group->in_completion_context) {
/* Same as above, but in a poll group. */
qpair->poll_group->num_qpairs_to_delete++;
qpair->delete_after_completion_context = 1;
return 0;
}
nvme_transport_ctrlr_disconnect_qpair(ctrlr, qpair);
if (qpair->poll_group) {

2
lib/nvme/nvme_internal.h
View File

@ -502,8 +502,6 @@ struct spdk_nvme_transport_poll_group {
STAILQ_HEAD(, spdk_nvme_qpair) connected_qpairs;
STAILQ_HEAD(, spdk_nvme_qpair) disconnected_qpairs;
STAILQ_ENTRY(spdk_nvme_transport_poll_group) link;
bool in_completion_context;
uint64_t num_qpairs_to_delete;
};
struct spdk_nvme_ns {

33
lib/nvme/nvme_transport.c
View File

@ -707,39 +707,8 @@ int64_t
nvme_transport_poll_group_process_completions(struct spdk_nvme_transport_poll_group *tgroup,
uint32_t completions_per_qpair, spdk_nvme_disconnected_qpair_cb disconnected_qpair_cb)
{
struct spdk_nvme_qpair *qpair;
int64_t rc;
tgroup->in_completion_context = true;
rc = tgroup->transport->ops.poll_group_process_completions(tgroup, completions_per_qpair,
return tgroup->transport->ops.poll_group_process_completions(tgroup, completions_per_qpair,
disconnected_qpair_cb);
tgroup->in_completion_context = false;
if (spdk_unlikely(tgroup->num_qpairs_to_delete > 0)) {
/* deleted qpairs are more likely to be in the disconnected qpairs list. */
STAILQ_FOREACH(qpair, &tgroup->disconnected_qpairs, poll_group_stailq) {
if (spdk_unlikely(qpair->delete_after_completion_context)) {
spdk_nvme_ctrlr_free_io_qpair(qpair);
if (--tgroup->num_qpairs_to_delete == 0) {
return rc;
}
}
}
STAILQ_FOREACH(qpair, &tgroup->connected_qpairs, poll_group_stailq) {
if (spdk_unlikely(qpair->delete_after_completion_context)) {
spdk_nvme_ctrlr_free_io_qpair(qpair);
if (--tgroup->num_qpairs_to_delete == 0) {
return rc;
}
}
}
/* Just in case. */
SPDK_DEBUGLOG(nvme, "Mismatch between qpairs to delete and poll group number.\n");
tgroup->num_qpairs_to_delete = 0;
}
return rc;
}
int

32
test/unit/lib/bdev/nvme/bdev_nvme.c/bdev_nvme_ut.c
View File

@ -261,8 +261,6 @@ struct spdk_nvme_poll_group {
struct spdk_nvme_accel_fn_table accel_fn_table;
TAILQ_HEAD(, spdk_nvme_qpair) connected_qpairs;
TAILQ_HEAD(, spdk_nvme_qpair) disconnected_qpairs;
bool in_completion_context;
uint64_t num_qpairs_to_delete;
};
struct spdk_nvme_probe_ctx {
@ -746,12 +744,6 @@ spdk_nvme_ctrlr_free_io_qpair(struct spdk_nvme_qpair *qpair)
return 0;
}
if (qpair->poll_group && qpair->poll_group->in_completion_context) {
qpair->poll_group->num_qpairs_to_delete++;
qpair->delete_after_completion_context = true;
return 0;
}
spdk_nvme_ctrlr_disconnect_io_qpair(qpair);
if (qpair->poll_group != NULL) {
@ -1136,8 +1128,6 @@ spdk_nvme_poll_group_process_completions(struct spdk_nvme_poll_group *group,
return -EINVAL;
}
group->in_completion_context = true;
TAILQ_FOREACH_SAFE(qpair, &group->disconnected_qpairs, poll_group_tailq, tmp_qpair) {
disconnected_qpair_cb(qpair, group->ctx);
}
@ -1158,28 +1148,6 @@ spdk_nvme_poll_group_process_completions(struct spdk_nvme_poll_group *group,
}
}
group->in_completion_context = false;
if (group->num_qpairs_to_delete > 0) {
TAILQ_FOREACH_SAFE(qpair, &group->disconnected_qpairs, poll_group_tailq, tmp_qpair) {
if (qpair->delete_after_completion_context) {
spdk_nvme_ctrlr_free_io_qpair(qpair);
CU_ASSERT(group->num_qpairs_to_delete > 0);
group->num_qpairs_to_delete--;
}
}
TAILQ_FOREACH_SAFE(qpair, &group->connected_qpairs, poll_group_tailq, tmp_qpair) {
if (qpair->delete_after_completion_context) {
spdk_nvme_ctrlr_free_io_qpair(qpair);
CU_ASSERT(group->num_qpairs_to_delete > 0);
group->num_qpairs_to_delete--;
}
}
CU_ASSERT(group->num_qpairs_to_delete == 0);
}
return error_reason ? error_reason : num_completions;
}