diff options
Diffstat (limited to 'drivers/s390/char/sclp_con.c')
| -rw-r--r-- | drivers/s390/char/sclp_con.c | 31 |
1 files changed, 30 insertions, 1 deletions
diff --git a/drivers/s390/char/sclp_con.c b/drivers/s390/char/sclp_con.c index ecf45c54f8c4..5880def98fc1 100644 --- a/drivers/s390/char/sclp_con.c +++ b/drivers/s390/char/sclp_con.c @@ -130,6 +130,31 @@ sclp_console_timeout(unsigned long data) } /* + * Drop oldest console buffer if sclp_con_drop is set + */ +static int +sclp_console_drop_buffer(void) +{ + struct list_head *list; + struct sclp_buffer *buffer; + void *page; + + if (!sclp_console_drop) + return 0; + list = sclp_con_outqueue.next; + if (sclp_con_queue_running) + /* The first element is in I/O */ + list = list->next; + if (list == &sclp_con_outqueue) + return 0; + list_del(list); + buffer = list_entry(list, struct sclp_buffer, list); + page = sclp_unmake_buffer(buffer); + list_add_tail((struct list_head *) page, &sclp_con_pages); + return 1; +} + +/* * Writes the given message to S390 system console */ static void @@ -150,9 +175,13 @@ sclp_console_write(struct console *console, const char *message, do { /* make sure we have a console output buffer */ if (sclp_conbuf == NULL) { + if (list_empty(&sclp_con_pages)) + sclp_console_full++; while (list_empty(&sclp_con_pages)) { if (sclp_con_suspended) goto out; + if (sclp_console_drop_buffer()) + break; spin_unlock_irqrestore(&sclp_con_lock, flags); sclp_sync_wait(); spin_lock_irqsave(&sclp_con_lock, flags); @@ -297,7 +326,7 @@ sclp_console_init(void) return rc; /* Allocate pages for output buffering */ INIT_LIST_HEAD(&sclp_con_pages); - for (i = 0; i < MAX_CONSOLE_PAGES; i++) { + for (i = 0; i < sclp_console_pages; i++) { page = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA); list_add_tail(page, &sclp_con_pages); } |