kernel/printk/printk_ringbuffer.c

273  *     push descriptor tail (id), then push descriptor head (id)
279  *     push descriptor tail (id), then set new descriptor reserved (state)
282  *     push descriptor tail (id), then set new descriptor reserved (state)
285  *     set new descriptor id and reserved (state), then allow writer changes
300  *     set new descriptor committed (state), then check descriptor head (id)
306  *     set descriptor reusable (state), then push descriptor tail (id)
337 #define DESC_ID_PREV_WRAP(desc_ring, id) \
338 DESC_ID((id) - DESCS_COUNT(desc_ring))
344  * @id:   the ID of the associated descriptor
351 	unsigned long	id;
388 	size = ALIGN(size, sizeof(db->id));
411 	if (size > DATA_SIZE(data_ring) - sizeof(db->id))
418 static enum desc_state get_desc_state(unsigned long id,
421 	if (id != DESC_ID(state_val))
437 				 unsigned long id, struct prb_desc *desc_out,
440 	struct printk_info *info = to_info(desc_ring, id);
441 	struct prb_desc *desc = to_desc(desc_ring, id);
448 	d_state = get_desc_state(id, state_val);
535 	d_state = get_desc_state(id, state_val);
548 			       unsigned long id)
550 	unsigned long val_finalized = DESC_SV(id, desc_finalized);
551 	unsigned long val_reusable = DESC_SV(id, desc_reusable);
552 	struct prb_desc *desc = to_desc(desc_ring, id);
580 	unsigned long id;
594 		id = blk->id; /* LMM(data_make_reusable:A) */
596 		d_state = desc_read(desc_ring, id, &desc,
611 			desc_make_reusable(desc_ring, id);
886 	unsigned long id;
891 		id = DESC_ID(head_id + 1);
892 		id_prev_wrap = DESC_ID_PREV_WRAP(desc_ring, id);
970 					  id)); /* LMM(desc_reserve:D) */
972 	desc = to_desc(desc_ring, id);
994 			DESC_SV(id, desc_reserved))) { /* LMM(desc_reserve:F) */
1001 	*id_out = id;
1029 			struct prb_data_blk_lpos *blk_lpos, unsigned long id)
1082 	blk->id = id; /* LMM(data_alloc:B) */
1092 		blk->id = id;
1103  * specified by @id. If the resized data block should become wrapped, it
1114 			  struct prb_data_blk_lpos *blk_lpos, unsigned long id)
1164 		blk->id = id;
1173 			       (blk_lpos->next - blk_lpos->begin) - sizeof(blk->id));
1255 	if (WARN_ON_ONCE(blk_lpos->begin != ALIGN(blk_lpos->begin, sizeof(db->id))) ||
1256 	    WARN_ON_ONCE(blk_lpos->next != ALIGN(blk_lpos->next, sizeof(db->id)))) {
1261 	if (WARN_ON_ONCE(*data_size < sizeof(db->id)))
1265 	*data_size -= sizeof(db->id);
1282 	unsigned long id;
1285 	id = atomic_long_read(&desc_ring->head_id);
1291 	d_state = desc_read(desc_ring, id, &desc, NULL, &cid);
1295 	d = to_desc(desc_ring, id);
1297 	prev_state_val = DESC_SV(id, desc_committed);
1316 			DESC_SV(id, desc_reserved))) { /* LMM(desc_reopen_last:A) */
1320 	*id_out = id;
1373 	unsigned long id;
1378 	d = desc_reopen_last(desc_ring, caller_id, &id);
1386 	info = to_info(desc_ring, id);
1393 	e->id = id;
1417 					 &d->text_blk_lpos, id);
1441 					   &d->text_blk_lpos, id);
1562 static void desc_make_final(struct printk_ringbuffer *rb, unsigned long id)
1565 	unsigned long prev_state_val = DESC_SV(id, desc_committed);
1566 	struct prb_desc *d = to_desc(desc_ring, id);
1569 			DESC_SV(id, desc_finalized))) { /* LMM(desc_make_final:A) */
1605 	unsigned long id;
1619 	if (!desc_reserve(rb, &id)) {
1626 	d = to_desc(desc_ring, id);
1627 	info = to_info(desc_ring, id);
1642 	e->id = id;
1655 	if (seq == 0 && DESC_INDEX(desc_ring, id) != 0)
1656 		info->seq = DESC_INDEX(desc_ring, id);
1667 		desc_make_final(rb, DESC_ID(id - 1));
1669 	r->text_buf = data_alloc(rb, r->text_buf_size, &d->text_blk_lpos, id);
1693 	struct prb_desc *d = to_desc(desc_ring, e->id);
1694 	unsigned long prev_state_val = DESC_SV(e->id, desc_reserved);
1722 			DESC_SV(e->id, state_val))) { /* LMM(_prb_commit:B) */
1759 	if (head_id != e->id)
1760 		desc_make_final(e->rb, e->id);
1867 				   unsigned long id, u64 seq,
1874 	d_state = desc_read(desc_ring, id, desc_out, &s, NULL);
1877 	 * An unexpected @id (desc_miss) or @seq mismatch means the record
1915 	unsigned long id;
1919 	id = DESC_ID(atomic_long_read(state_var));
1922 	err = desc_read_finalized_seq(desc_ring, id, seq, &desc);
1942 	return desc_read_finalized_seq(desc_ring, id, seq, &desc);
1951 	unsigned long id;
1955 		id = atomic_long_read(&rb->desc_ring.tail_id); /* LMM(prb_first_seq:A) */
1957 		d_state = desc_read(desc_ring, id, &desc, &seq, NULL); /* LMM(prb_first_seq:B) */