Commit 5f6c7648 authored by John Ogness's avatar John Ogness Committed by Petr Mladek
Browse files

printk: kmsg_dumper: remove @active field 



All 6 kmsg_dumpers do not benefit from the @active flag:

  (provide their own synchronization)
  - arch/powerpc/kernel/nvram_64.c
  - arch/um/kernel/kmsg_dump.c
  - drivers/mtd/mtdoops.c
  - fs/pstore/platform.c

  (only dump on KMSG_DUMP_PANIC, which does not require
  synchronization)
  - arch/powerpc/platforms/powernv/opal-kmsg.c
  - drivers/hv/vmbus_drv.c

The other 2 kmsg_dump users also do not rely on @active:

  (hard-code @active to always be true)
  - arch/powerpc/xmon/xmon.c
  - kernel/debug/kdb/kdb_main.c

Therefore, @active can be removed.

Signed-off-by: default avatarJohn Ogness <john.ogness@linutronix.de>
Reviewed-by: default avatarPetr Mladek <pmladek@suse.com>
Signed-off-by: default avatarPetr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210303101528.29901-12-john.ogness@linutronix.de
parent 636babdc

arch/powerpc/xmon/xmon.c

+1 −1
Original line number Diff line number Diff line
@@ -3005,7 +3005,7 @@ print_address(unsigned long addr) 
static void

dump_log_buf(void)

{

	struct kmsg_dumper dumper = { .active = 1 };

	struct kmsg_dumper dumper;

	unsigned char buf[128];

	size_t len;

include/linux/kmsg_dump.h

+0 −2
Original line number Diff line number Diff line
@@ -36,7 +36,6 @@ enum kmsg_dump_reason { 
 * 		through the record iterator

 * @max_reason:	filter for highest reason number that should be dumped

 * @registered:	Flag that specifies if this is already registered

 * @active:	Flag that specifies if this is currently dumping

 * @cur_seq:	Points to the oldest message to dump

 * @next_seq:	Points after the newest message to dump

 */
@@ -44,7 +43,6 @@ struct kmsg_dumper { 
	struct list_head list;

	void (*dump)(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason);

	enum kmsg_dump_reason max_reason;

	bool active;

	bool registered;



	/* private state of the kmsg iterator */

kernel/debug/kdb/kdb_main.c

+1 −1
Original line number Diff line number Diff line
@@ -2101,7 +2101,7 @@ static int kdb_dmesg(int argc, const char **argv) 
	int adjust = 0;

	int n = 0;

	int skip = 0;

	struct kmsg_dumper dumper = { .active = 1 };

	struct kmsg_dumper dumper;

	size_t len;

	char buf[201];

kernel/printk/printk.c

+1 −9
Original line number Diff line number Diff line
@@ -3408,8 +3408,6 @@ void kmsg_dump(enum kmsg_dump_reason reason) 
			continue;



		/* initialize iterator with data about the stored records */

		dumper->active = true;



		logbuf_lock_irqsave(flags);

		dumper->cur_seq = latched_seq_read_nolock(&clear_seq);

		dumper->next_seq = prb_next_seq(prb);
@@ -3417,9 +3415,6 @@ void kmsg_dump(enum kmsg_dump_reason reason) 


		/* invoke dumper which will iterate over records */

		dumper->dump(dumper, reason);



		/* reset iterator */

		dumper->active = false;

	}

	rcu_read_unlock();

}
@@ -3454,9 +3449,6 @@ bool kmsg_dump_get_line_nolock(struct kmsg_dumper *dumper, bool syslog, 


	prb_rec_init_rd(&r, &info, line, size);



	if (!dumper->active)

		goto out;



	/* Read text or count text lines? */

	if (line) {

		if (!prb_read_valid(prb, dumper->cur_seq, &r))
@@ -3542,7 +3534,7 @@ bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog, 
	bool ret = false;

	bool time = printk_time;



	if (!dumper->active || !buf || !size)

	if (!buf || !size)

		goto out;



	logbuf_lock_irqsave(flags);