The only place that uses LOG_PREFIX is log_store(), and that now strips it from the flags field before recording it in a log buffer.
Switch to passing a Boolean flag to log_store() to indicate whether this record should force a new record--that is, complete the previous one--and eliminate the LOG_PREFIX flag altogether. Update a few comments as well. Signed-off-by: Alex Elder <[email protected]> --- kernel/printk/printk.c | 60 ++++++++++++++++++++++++++------------------------ 1 file changed, 31 insertions(+), 29 deletions(-) diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index df38b5e..bfc2581 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -210,7 +210,6 @@ static int console_may_schedule; enum log_flags { LOG_NOCONS = 1, /* already flushed, do not print to console */ LOG_NEWLINE = 2, /* text ended with a newline */ - LOG_PREFIX = 4, /* text started with a prefix */ }; struct printk_log { @@ -397,7 +396,7 @@ static u32 truncate_msg(u16 *text_len, u16 *trunc_msg_len, } /* insert record into the buffer, discard old ones, update heads */ -static int log_store(int facility, int level, +static int log_store(int facility, int level, bool force_new, enum log_flags flags, u64 ts_nsec, const char *dict, u16 dict_len, const char *text, u16 text_len) @@ -432,11 +431,8 @@ static int log_store(int facility, int level, * If we're forcing a new log record, update the flags for * the previous one to mark it complete. */ - if (flags & LOG_PREFIX) { - if (log_last_msg) - log_last_msg->flags |= LOG_NEWLINE; - flags &= ~LOG_PREFIX; - } + if (force_new && log_last_msg) + log_last_msg->flags |= LOG_NEWLINE; msg = (struct printk_log *)(log_buf + log_next_idx); memcpy(log_text(msg), text, text_len); @@ -1493,7 +1489,7 @@ static struct cont { u64 ts_nsec; /* time of first print */ u8 level; /* log level of first message */ u8 facility; /* log level of first message */ - enum log_flags flags; /* prefix, newline flags */ + enum log_flags flags; /* nocons, newline flags */ bool flushed:1; /* buffer sealed and committed */ } cont; @@ -1510,7 +1506,7 @@ static void cont_flush(enum log_flags flags) * console; wait for the console to pick up the rest of the * line. LOG_NOCONS suppresses a duplicated output. */ - log_store(cont.facility, cont.level, flags | LOG_NOCONS, + log_store(cont.facility, cont.level, false, flags | LOG_NOCONS, cont.ts_nsec, NULL, 0, cont.buf, cont.len); cont.flags = flags; cont.flushed = true; @@ -1519,7 +1515,7 @@ static void cont_flush(enum log_flags flags) * If no fragment of this line ever reached the console, * just submit it to the store and free the buffer. */ - log_store(cont.facility, cont.level, flags, 0, + log_store(cont.facility, cont.level, false, flags, 0, NULL, 0, cont.buf, cont.len); cont.len = 0; } @@ -1596,6 +1592,7 @@ asmlinkage int vprintk_emit(int facility, int level, int this_cpu; int printed_len = 0; bool in_sched = false; + bool force_new = false; /* cpu currently holding logbuf_lock in this function */ static volatile unsigned int logbuf_cpu = UINT_MAX; @@ -1640,7 +1637,7 @@ asmlinkage int vprintk_emit(int facility, int level, recursion_bug = 0; text_len = strlen(recursion_msg); /* emit KERN_CRIT message */ - printed_len += log_store(0, 2, LOG_PREFIX|LOG_NEWLINE, 0, + printed_len += log_store(0, 2, true, LOG_NEWLINE, 0, NULL, 0, recursion_msg, text_len); } @@ -1676,7 +1673,7 @@ asmlinkage int vprintk_emit(int facility, int level, if (level == -1) level = kern_level - '0'; case 'd': /* KERN_DEFAULT */ - lflags |= LOG_PREFIX; + force_new = true; } /* * No need to check length here because vscnprintf @@ -1691,36 +1688,40 @@ asmlinkage int vprintk_emit(int facility, int level, if (level == -1) level = default_message_loglevel; - if (dict) - lflags = LOG_PREFIX|LOG_NEWLINE; + if (dict) { + force_new = true; + lflags = LOG_NEWLINE; + } if (!(lflags & LOG_NEWLINE)) { /* - * Flush the conflicting buffer. An earlier newline was missing, - * or another task also prints continuation lines. + * We're recording an incomplete record. We'll add it to the + * "cont" buffer if possible, but if it contains data written + * by somebody else we need to flush that to the log first. */ - if (cont.len && (lflags & LOG_PREFIX || cont.owner != current)) + if (cont.len && (force_new || cont.owner != current)) cont_flush(LOG_NEWLINE); - /* buffer line if possible, otherwise store it right away */ + /* If we're unable to buffer it, store it immediately */ if (cont_add(facility, level, text, text_len)) printed_len += text_len; else - printed_len += log_store(facility, level, lflags, 0, - NULL, 0, text, text_len); + printed_len += log_store(facility, level, force_new, + lflags, 0, NULL, 0, + text, text_len); } else { bool stored = false; /* - * If an earlier newline was missing and it was the same task, - * either merge it with the current buffer and flush, or if - * there was a race with interrupts (prefix == true) then just - * flush it out and store this line separately. - * If the preceding printk was from a different task and missed - * a newline, flush and append the newline. + * This record is complete (it should be formatted with a + * newline), so we'll be writing it to the log. If there + * are any incomplete records buffered we will need to + * flush those to the log first. If possible, we'll add + * this record to the buffer first. If there's nothing + * buffered, just write this record to the log. */ if (cont.len) { - if (cont.owner == current && !(lflags & LOG_PREFIX)) + if (cont.owner == current && !force_new) stored = cont_add(facility, level, text, text_len); cont_flush(LOG_NEWLINE); @@ -1729,8 +1730,9 @@ asmlinkage int vprintk_emit(int facility, int level, if (stored) printed_len += text_len; else - printed_len += log_store(facility, level, lflags, 0, - dict, dictlen, text, text_len); + printed_len += log_store(facility, level, force_new, + lflags, 0, dict, dictlen, + text, text_len); } logbuf_cpu = UINT_MAX; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
