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Message-Id: <20210126211551.26536-13-john.ogness@linutronix.de>
Date: Tue, 26 Jan 2021 22:21:51 +0106
From: John Ogness <john.ogness@...utronix.de>
To: Petr Mladek <pmladek@...e.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@...il.com>,
Sergey Senozhatsky <sergey.senozhatsky@...il.com>,
Steven Rostedt <rostedt@...dmis.org>,
Thomas Gleixner <tglx@...utronix.de>,
linux-kernel@...r.kernel.org
Subject: [PATCH printk-rework 12/12] printk: kmsg_dump: remove _nolock() variants
kmsg_dump_rewind() and kmsg_dump_get_line() are lockless, so there is
no need for _nolock() variants. Remove these functions and switch all
callers of the _nolock() variants.
The functions without _nolock() were chosen because they are already
exported to kernel modules.
Signed-off-by: John Ogness <john.ogness@...utronix.de>
---
arch/powerpc/xmon/xmon.c | 4 +--
include/linux/kmsg_dump.h | 18 +------------
kernel/debug/kdb/kdb_main.c | 8 +++---
kernel/printk/printk.c | 52 +++++--------------------------------
4 files changed, 13 insertions(+), 69 deletions(-)
diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c
index 43162b885259..4cac114ba32d 100644
--- a/arch/powerpc/xmon/xmon.c
+++ b/arch/powerpc/xmon/xmon.c
@@ -3015,9 +3015,9 @@ dump_log_buf(void)
catch_memory_errors = 1;
sync();
- kmsg_dump_rewind_nolock(&iter);
+ kmsg_dump_rewind(&iter);
xmon_start_pagination();
- while (kmsg_dump_get_line_nolock(&iter, false, buf, sizeof(buf), &len)) {
+ while (kmsg_dump_get_line(&iter, false, buf, sizeof(buf), &len)) {
buf[len] = '\0';
printf("%s", buf);
}
diff --git a/include/linux/kmsg_dump.h b/include/linux/kmsg_dump.h
index ecc98f549d93..8a39d898a1a5 100644
--- a/include/linux/kmsg_dump.h
+++ b/include/linux/kmsg_dump.h
@@ -60,18 +60,13 @@ struct kmsg_dumper {
#ifdef CONFIG_PRINTK
void kmsg_dump(enum kmsg_dump_reason reason);
-bool kmsg_dump_get_line_nolock(struct kmsg_dumper_iter *iter, bool syslog,
- char *line, size_t size, size_t *len);
-
bool kmsg_dump_get_line(struct kmsg_dumper_iter *iter, bool syslog,
char *line, size_t size, size_t *len);
bool kmsg_dump_get_buffer(struct kmsg_dumper_iter *iter, bool syslog,
char *buf, size_t size, size_t *len_out);
-void kmsg_dump_rewind_nolock(struct kmsg_dumper_iter *iter);
-
-void kmsg_dump_rewind(struct kmsg_dumper_iter *dumper_iter);
+void kmsg_dump_rewind(struct kmsg_dumper_iter *iter);
int kmsg_dump_register(struct kmsg_dumper *dumper);
@@ -83,13 +78,6 @@ static inline void kmsg_dump(enum kmsg_dump_reason reason)
{
}
-static inline bool kmsg_dump_get_line_nolock(struct kmsg_dumper_iter *iter,
- bool syslog, const char *line,
- size_t size, size_t *len)
-{
- return false;
-}
-
static inline bool kmsg_dump_get_line(struct kmsg_dumper_iter *iter, bool syslog,
const char *line, size_t size, size_t *len)
{
@@ -102,10 +90,6 @@ static inline bool kmsg_dump_get_buffer(struct kmsg_dumper_iter *iter, bool sysl
return false;
}
-static inline void kmsg_dump_rewind_nolock(struct kmsg_dumper_iter *iter)
-{
-}
-
static inline void kmsg_dump_rewind(struct kmsg_dumper_iter *iter)
{
}
diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index 7ae9da245e4b..dbf1d126ac5e 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -2126,8 +2126,8 @@ static int kdb_dmesg(int argc, const char **argv)
kdb_set(2, setargs);
}
- kmsg_dump_rewind_nolock(&iter);
- while (kmsg_dump_get_line_nolock(&iter, 1, NULL, 0, NULL))
+ kmsg_dump_rewind(&iter);
+ while (kmsg_dump_get_line(&iter, 1, NULL, 0, NULL))
n++;
if (lines < 0) {
@@ -2159,8 +2159,8 @@ static int kdb_dmesg(int argc, const char **argv)
if (skip >= n || skip < 0)
return 0;
- kmsg_dump_rewind_nolock(&iter);
- while (kmsg_dump_get_line_nolock(&iter, 1, buf, sizeof(buf), &len)) {
+ kmsg_dump_rewind(&iter);
+ while (kmsg_dump_get_line(&iter, 1, buf, sizeof(buf), &len)) {
if (skip) {
skip--;
continue;
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index b57dba7f077d..a2d4ba00bf77 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -3333,7 +3333,7 @@ void kmsg_dump(enum kmsg_dump_reason reason)
/* initialize iterator with data about the stored records */
iter.active = true;
- kmsg_dump_rewind_nolock(&iter);
+ kmsg_dump_rewind(&iter);
/* invoke dumper which will iterate over records */
dumper->dump(dumper, reason, &iter);
@@ -3342,7 +3342,7 @@ void kmsg_dump(enum kmsg_dump_reason reason)
}
/**
- * kmsg_dump_get_line_nolock - retrieve one kmsg log line (unlocked version)
+ * kmsg_dump_get_line - retrieve one kmsg log line
* @iter: kmsg dumper iterator
* @syslog: include the "<4>" prefixes
* @line: buffer to copy the line to
@@ -3357,11 +3357,9 @@ void kmsg_dump(enum kmsg_dump_reason reason)
*
* A return value of FALSE indicates that there are no more records to
* read.
- *
- * The function is similar to kmsg_dump_get_line(), but grabs no locks.
*/
-bool kmsg_dump_get_line_nolock(struct kmsg_dumper_iter *iter, bool syslog,
- char *line, size_t size, size_t *len)
+bool kmsg_dump_get_line(struct kmsg_dumper_iter *iter, bool syslog,
+ char *line, size_t size, size_t *len)
{
struct printk_info info;
unsigned int line_count;
@@ -3399,29 +3397,6 @@ bool kmsg_dump_get_line_nolock(struct kmsg_dumper_iter *iter, bool syslog,
*len = l;
return ret;
}
-
-/**
- * kmsg_dump_get_line - retrieve one kmsg log line
- * @iter: kmsg dumper iterator
- * @syslog: include the "<4>" prefixes
- * @line: buffer to copy the line to
- * @size: maximum size of the buffer
- * @len: length of line placed into buffer
- *
- * Start at the beginning of the kmsg buffer, with the oldest kmsg
- * record, and copy one record into the provided buffer.
- *
- * Consecutive calls will return the next available record moving
- * towards the end of the buffer with the youngest messages.
- *
- * A return value of FALSE indicates that there are no more records to
- * read.
- */
-bool kmsg_dump_get_line(struct kmsg_dumper_iter *iter, bool syslog,
- char *line, size_t size, size_t *len)
-{
- return kmsg_dump_get_line_nolock(iter, syslog, line, size, len);
-}
EXPORT_SYMBOL_GPL(kmsg_dump_get_line);
/**
@@ -3506,16 +3481,14 @@ bool kmsg_dump_get_buffer(struct kmsg_dumper_iter *iter, bool syslog,
EXPORT_SYMBOL_GPL(kmsg_dump_get_buffer);
/**
- * kmsg_dump_rewind_nolock - reset the iterator (unlocked version)
+ * kmsg_dump_rewind - reset the iterator
* @iter: kmsg dumper iterator
*
* Reset the dumper's iterator so that kmsg_dump_get_line() and
* kmsg_dump_get_buffer() can be called again and used multiple
* times within the same dumper.dump() callback.
- *
- * The function is similar to kmsg_dump_rewind(), but grabs no locks.
*/
-void kmsg_dump_rewind_nolock(struct kmsg_dumper_iter *iter)
+void kmsg_dump_rewind(struct kmsg_dumper_iter *iter)
{
unsigned long flags;
@@ -3524,19 +3497,6 @@ void kmsg_dump_rewind_nolock(struct kmsg_dumper_iter *iter)
iter->next_seq = prb_next_seq(prb);
printk_safe_exit_irqrestore(flags);
}
-
-/**
- * kmsg_dump_rewind - reset the iterator
- * @iter: kmsg dumper iterator
- *
- * Reset the dumper's iterator so that kmsg_dump_get_line() and
- * kmsg_dump_get_buffer() can be called again and used multiple
- * times within the same dumper.dump() callback.
- */
-void kmsg_dump_rewind(struct kmsg_dumper_iter *iter)
-{
- kmsg_dump_rewind_nolock(iter);
-}
EXPORT_SYMBOL_GPL(kmsg_dump_rewind);
#endif
--
2.20.1
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