summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorManjunath Patil <manjunath.b.patil@oracle.com>2024-03-08 22:33:23 -0800
committerLeon Romanovsky <leon@kernel.org>2024-03-10 13:17:54 +0200
commit96d9cbe2f2ff7abde021bac75eafaceabe9a51fa (patch)
tree06f5ce1c681da5d07cdbd2f0e22dbdb8b5c4067d
parent2d5c00815778ec4f4e0a84e405e3e157b7815db1 (diff)
RDMA/cm: add timeout to cm_destroy_id wait
Add timeout to cm_destroy_id, so that userspace can trigger any data collection that would help in analyzing the cause of delay in destroying the cm_id. New noinline function helps dtrace/ebpf programs to hook on to it. Existing functionality isn't changed except triggering a probe-able new function at every timeout interval. We have seen cases where CM messages stuck with MAD layer (either due to software bug or faulty HCA), leading to cm_id getting stuck in the following call stack. This patch helps in resolving such issues faster. kernel: ... INFO: task XXXX:56778 blocked for more than 120 seconds. ... Call Trace: __schedule+0x2bc/0x895 schedule+0x36/0x7c schedule_timeout+0x1f6/0x31f ? __slab_free+0x19c/0x2ba wait_for_completion+0x12b/0x18a ? wake_up_q+0x80/0x73 cm_destroy_id+0x345/0x610 [ib_cm] ib_destroy_cm_id+0x10/0x20 [ib_cm] rdma_destroy_id+0xa8/0x300 [rdma_cm] ucma_destroy_id+0x13e/0x190 [rdma_ucm] ucma_write+0xe0/0x160 [rdma_ucm] __vfs_write+0x3a/0x16d vfs_write+0xb2/0x1a1 ? syscall_trace_enter+0x1ce/0x2b8 SyS_write+0x5c/0xd3 do_syscall_64+0x79/0x1b9 entry_SYSCALL_64_after_hwframe+0x16d/0x0 Signed-off-by: Manjunath Patil <manjunath.b.patil@oracle.com> Link: https://lore.kernel.org/r/20240309063323.458102-1-manjunath.b.patil@oracle.com Signed-off-by: Leon Romanovsky <leon@kernel.org>
-rw-r--r--drivers/infiniband/core/cm.c20
1 files changed, 19 insertions, 1 deletions
diff --git a/drivers/infiniband/core/cm.c b/drivers/infiniband/core/cm.c
index ff58058aeadc..bf0df6ee4f78 100644
--- a/drivers/infiniband/core/cm.c
+++ b/drivers/infiniband/core/cm.c
@@ -34,6 +34,7 @@ MODULE_AUTHOR("Sean Hefty");
MODULE_DESCRIPTION("InfiniBand CM");
MODULE_LICENSE("Dual BSD/GPL");
+#define CM_DESTROY_ID_WAIT_TIMEOUT 10000 /* msecs */
static const char * const ibcm_rej_reason_strs[] = {
[IB_CM_REJ_NO_QP] = "no QP",
[IB_CM_REJ_NO_EEC] = "no EEC",
@@ -1025,10 +1026,20 @@ static void cm_reset_to_idle(struct cm_id_private *cm_id_priv)
}
}
+static noinline void cm_destroy_id_wait_timeout(struct ib_cm_id *cm_id)
+{
+ struct cm_id_private *cm_id_priv;
+
+ cm_id_priv = container_of(cm_id, struct cm_id_private, id);
+ pr_err("%s: cm_id=%p timed out. state=%d refcnt=%d\n", __func__,
+ cm_id, cm_id->state, refcount_read(&cm_id_priv->refcount));
+}
+
static void cm_destroy_id(struct ib_cm_id *cm_id, int err)
{
struct cm_id_private *cm_id_priv;
struct cm_work *work;
+ int ret;
cm_id_priv = container_of(cm_id, struct cm_id_private, id);
spin_lock_irq(&cm_id_priv->lock);
@@ -1135,7 +1146,14 @@ retest:
xa_erase(&cm.local_id_table, cm_local_id(cm_id->local_id));
cm_deref_id(cm_id_priv);
- wait_for_completion(&cm_id_priv->comp);
+ do {
+ ret = wait_for_completion_timeout(&cm_id_priv->comp,
+ msecs_to_jiffies(
+ CM_DESTROY_ID_WAIT_TIMEOUT));
+ if (!ret) /* timeout happened */
+ cm_destroy_id_wait_timeout(cm_id);
+ } while (!ret);
+
while ((work = cm_dequeue_work(cm_id_priv)) != NULL)
cm_free_work(work);