Soft lockup during cache start

[Kamoppl]

Description

During cache startup, a soft lockup may occur on slower machine (triggered with low cache line size).

Expected Behavior

Cache starts without soft lockups

Actual Behavior

Soft lockup during cache start (cache starts after a while)

Steps to Reproduce

1. Start cache

Context

Possible Fix

Logs

Configuration files

Your Environment

• OpenCAS version (commit hash or tag): v25.03

• Operating System: Ubuntu 22.05

• Kernel version: 5.15.144

• Cache device type (NAND/Optane/other):

• Core device type (HDD/SSD/other):

• Cache configuration:

• • Cache mode: (default: wt)
• • Cache line size: (default: 4)
• • Promotion policy: (default: always)
• • Cleaning policy: (default: alru)
• • Sequential cutoff policy: (default: full)

• Other (e.g. lsblk, casadm -P, casadm -L)

soft_lockup_cache_start.txt

[mmichal10]

Adding cond_reschedule() or using the parallelize ocf api should resolve the issue.
The softlockup was triggered by:

ocf/src/concurrency/ocf_metadata_concurrency.c

Lines 83 to 87 in 989fb2c

	for (i = 0; i < hash_table_entries; i++) {
	err = env_rwsem_init(&metadata_lock->hash[i]);
	if (err)
	break;
	}