fs/xfs/xfs_log_priv.h

1 // SPDX-License-Identifier: GPL-2.0
3  * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
4  * All Rights Reserved.
63  * By covering, we mean changing the h_tail_lsn in the last on-disk
64  * log write such that no allocation transactions will be re-done during
65  * recovery after a system crash. Recovery starts at the last on-disk
69  * space allocation transactions which can undo non-transactional changes
82  * non-dummy transaction. The first dummy changes the h_tail_lsn to
91  *  IDLE -- no logging has been done on the file system or
93  *  NEED -- logging has occurred and we need a dummy transaction
95  *  DONE -- we were in the NEED state and have committed a dummy
97  *  NEED2 -- we detected that a dummy transaction has gone to the
99  *  DONE2 -- we committed a dummy transaction when in the NEED2 state.
107  * 2.) When we finish writing the on-disk log (xlog_state_clean_log).
170  * - A log record header is 512 bytes.  There is plenty of room to grow the
171  *	xlog_rec_header_t into the reserved space.
172  * - ic_data follows, so a write to disk can start at the beginning of
174  * - ic_forcewait is used to implement synchronous forcing of the iclog to disk.
175  * - ic_next is the pointer to the next iclog in the ring.
176  * - ic_log is a pointer back to the global log structure.
177  * - ic_size is the full size of the log buffer, minus the cycle headers.
178  * - ic_offset is the current number of bytes written to in this iclog.
179  * - ic_refcnt is bumped when someone is writing to the log.
180  * - ic_state is the state of the iclog.
187  *	- ic_callbacks
188  *	- ic_refcnt
189  *	- fields protected by the global l_icloglock
192  * We'll put all the read-only and l_icloglock fields in the first cacheline,
213 #define ic_header	ic_data->hic_header
224  * The CIL context is used to aggregate per-transaction details as well be
225  * passed to the iclog for checkpoint post-commit processing.  After being
285  * track both space consumed and the number of vectors in the checkpoint
288  * Every log buffer we write out during a push needs a header reserved, which
293  * io vectors, so limiting on a specific number of vectors is going to result
321  * CIL is large enough to maintain sufficient in-memory relogging to avoid
325  * issues when we are running low on memory - pinned memory cannot be reclaimed,
332  * - a threshold large enough that it allows CIL to be pushed and progress to be
334  *   defined to be 12.5% of the log space - half the 25% push threshold of the
336  * - small enough that it doesn't pin excessive amounts of memory but maintains
346  * yeild the CPU, giving the CIL push work a chance to be scheduled and start
348  * the CIL because it is not yielding the CPU. We set the blocking limit at
352  * Note: this is not a -hard- limit as blocking is applied after the transaction
363 	min_t(int, (log)->l_logsize >> 3, BBTOB(XLOG_TOTAL_REC_SHIFT(log)) << 4)
442 	((log)->l_buf_cancel_table + ((uint64_t)blkno % XLOG_BC_TABLE_SIZE))
445 	(unlikely((log)->l_flags & XLOG_IO_ERROR))
473 	*len -= bytes;  in xlog_write_adv_cnt()
562 	xlog_cil_force_lsn(log, log->l_cilp->xc_current_sequence);  in xlog_cil_force()
612 	cur_cycle = READ_ONCE(log->l_curr_cycle);  in xlog_valid_lsn()
614 	cur_block = READ_ONCE(log->l_curr_block);  in xlog_valid_lsn()
623 		spin_lock(&log->l_icloglock);  in xlog_valid_lsn()
624 		cur_cycle = log->l_curr_cycle;  in xlog_valid_lsn()
625 		cur_block = log->l_curr_block;  in xlog_valid_lsn()
626 		spin_unlock(&log->l_icloglock);  in xlog_valid_lsn()