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ebbbab66bd
Convert wait_caps_flush() from a silent indefinite wait into a diagnostic wait loop that periodically dumps pending cap flush state. The underlying wait semantics remain intact: callers still wait until the requested cap flushes complete. The difference is that long stalls now produce actionable diagnostics instead of looking like a silent hang. CEPH_CAP_FLUSH_MAX_DUMP_ENTRIES limits the number of entries emitted per diagnostic dump, and CEPH_CAP_FLUSH_MAX_DUMP_ITERS limits the number of timed diagnostic dumps before the wait continues silently. When more entries exist than the per-dump limit, a truncation count is reported. When the dump iteration limit is reached, a final suppression message is emitted so the transition to silence is explicit. The diagnostic dump collects flush entry data under cap_dirty_lock into a bounded on-stack array, then prints after releasing the lock. This avoids holding the spinlock across printk calls. A null cf->ci on the global flush list indicates a bug since all cap_flush entries are initialized with a valid ci before being added. Signal this with WARN_ON_ONCE while still printing enough context for debugging. READ_ONCE is used for the i_last_cap_flush_ack field, which is read outside the inode lock domain. Flush tids are monotonically increasing and acks are processed in order under i_ceph_lock, so the latest ack tid is always the most recently written value. Add a ci pointer to struct ceph_cap_flush so that the diagnostic dump can identify which inode each pending flush belongs to. The new i_last_cap_flush_ack field tracks the latest acknowledged flush tid per inode for diagnostic correlation. This improves reset-drain observability and is also useful for existing sync and writeback troubleshooting paths. Signed-off-by: Alex Markuze <amarkuze@redhat.com> Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com> Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
3258 lines
91 KiB
3258 lines
91 KiB