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RDMA/cm: Base cm_id destruction timeout on CMA values

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When a GSI MAD packet is sent on the QP, it will potentially be
retried CMA_MAX_CM_RETRIES times with a timeout value of:

    4.096usec * 2 ^ CMA_CM_RESPONSE_TIMEOUT

The above equates to ~64 seconds using the default CMA values.

The cm_id_priv's refcount will be incremented for this period.
Therefore, the timeout value waiting for a cm_id destruction must be
based on the effective timeout of MAD packets.  To provide additional
leeway, we add 25% to this timeout and use that instead of the
constant 10 seconds timeout, which may result in false negatives.

Signed-off-by: Håkon Bugge <haakon.bugge@oracle.com>
Link: https://patch.msgid.link/20251021132738.4179604-1-haakon.bugge@oracle.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>
This commit is contained in:
Håkon Bugge
2025-10-21 15:27:33 +02:00
committed by Leon Romanovsky
parent be180c847a
commit 58aca1f3de
1 changed files with 3 additions and 4 deletions
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7
drivers/infiniband/core/cm.c
View File

@@ -34,7 +34,6 @@ MODULE_AUTHOR("Sean Hefty");
MODULE_DESCRIPTION("InfiniBand CM");
MODULE_LICENSE("Dual BSD/GPL");
#define CM_DESTROY_ID_WAIT_TIMEOUT 10000 /* msecs */
#define CM_DIRECT_RETRY_CTX ((void *) 1UL)
#define CM_MRA_SETTING 24 /* 4.096us * 2^24 = ~68.7 seconds */
@@ -1057,6 +1056,7 @@ static void cm_destroy_id(struct ib_cm_id *cm_id, int err)
{
struct cm_id_private *cm_id_priv;
enum ib_cm_state old_state;
unsigned long timeout;
struct cm_work *work;
int ret;
@@ -1167,10 +1167,9 @@ retest:
xa_erase(&cm.local_id_table, cm_local_id(cm_id->local_id));
cm_deref_id(cm_id_priv);
timeout = msecs_to_jiffies((cm_id_priv->max_cm_retries * cm_id_priv->timeout_ms * 5) / 4);
do {
ret = wait_for_completion_timeout(&cm_id_priv->comp,
msecs_to_jiffies(
CM_DESTROY_ID_WAIT_TIMEOUT));
ret = wait_for_completion_timeout(&cm_id_priv->comp, timeout);
if (!ret) /* timeout happened */
cm_destroy_id_wait_timeout(cm_id, old_state);
} while (!ret);