mbox series

[printk,v5,0/8] provide nbcon base

Message ID 20230916192007.608398-1-john.ogness@linutronix.de
Headers
Series provide nbcon base |

Message

John Ogness Sept. 16, 2023, 7:19 p.m. UTC 
  Hi,

This is v5 of a series to introduce the new non-BKL (nbcon)
consoles. v4 is here [0]. For information about the motivation
of the atomic consoles, please read the cover letter of v1 [1].

This series focuses on providing the base functionality of the
nbcon consoles. In particular, it implements the ownership and
priority semantics for nbcon consoles. This series does _not_
include threaded printing, atomic printing regions, or nbcon
drivers. Those features will be added in separate follow-up
series.

The changes since v4:

- Remove nbcon_seq_init() and use nbcon_seq_force() instead.

- For nbcon_seq_force(), use the oldest record if the specified
  record no longer exists.

- For all try_acquire_*() variants, do not update the nbcon
  state on success since it was not used.

- For nbcon_context_try_acquire_requested(), replace the cmpxhg
  loop with a single cmpxchg.

- For nbcon_context_try_acquire_requested(), remove an explicit
  check for @unsafe_takeover. The nbcon_waiter_matches() check
  is enough to detect unsafe hostile takeovers.

- Rename nbcon_context_acquire_hostile() back to
  nbcon_context_try_acquire_hostile().

- Decide in nbcon_context_try_acquire_hostile() if an unsafe
  hostile acquire is allowed rather than at the end of and
  after nbcon_context_try_acquire_handover().

- For register_console(), call nbcon_free() if it is a braille
  console.

- Change many comments as suggested by pmladek. In the feedback
  thread I mentioned some other comment changes that I made.

- Added various WARN_ON_ONCE() checks as suggested by pmladek.

John Ogness

[0] https://lore.kernel.org/lkml/20230908185008.468566-1-john.ogness@linutronix.de

[1] https://lore.kernel.org/lkml/20230302195618.156940-1-john.ogness@linutronix.de

John Ogness (1):
  printk: Make static printk buffers available to nbcon

Thomas Gleixner (7):
  printk: Add non-BKL (nbcon) console basic infrastructure
  printk: nbcon: Add acquire/release logic
  printk: nbcon: Add buffer management
  printk: nbcon: Add ownership state functions
  printk: nbcon: Add sequence handling
  printk: nbcon: Add emit function and callback function for atomic
    printing
  printk: nbcon: Allow drivers to mark unsafe regions and check state

 include/linux/console.h  |  129 +++++
 kernel/printk/Makefile   |    2 +-
 kernel/printk/internal.h |   31 ++
 kernel/printk/nbcon.c    | 1029 ++++++++++++++++++++++++++++++++++++++
 kernel/printk/printk.c   |   78 ++-
 5 files changed, 1245 insertions(+), 24 deletions(-)
 create mode 100644 kernel/printk/nbcon.c


base-commit: 189f53ec666838729ab29a220ca4c1e1f1359f95

Comments

Petr Mladek Sept. 18, 2023, 2:54 p.m. UTC | #1 
On Sat 2023-09-16 21:25:59, John Ogness wrote:
> Hi,
> 
> This is v5 of a series to introduce the new non-BKL (nbcon)
> consoles. v4 is here [0]. For information about the motivation
> of the atomic consoles, please read the cover letter of v1 [1].
> 
> This series focuses on providing the base functionality of the
> nbcon consoles. In particular, it implements the ownership and
> priority semantics for nbcon consoles. This series does _not_
> include threaded printing, atomic printing regions, or nbcon
> drivers. Those features will be added in separate follow-up
> series.

This series seems to be ready for linux-next and I am going to
push it.

Thanks a lot for the effort.

Best Regards,
Petr
Petr Mladek Sept. 19, 2023, 12:08 p.m. UTC | #2 
On Mon 2023-09-18 16:54:06, Petr Mladek wrote:
> On Sat 2023-09-16 21:25:59, John Ogness wrote:
> > Hi,
> > 
> > This is v5 of a series to introduce the new non-BKL (nbcon)
> > consoles. v4 is here [0]. For information about the motivation
> > of the atomic consoles, please read the cover letter of v1 [1].
> > 
> > This series focuses on providing the base functionality of the
> > nbcon consoles. In particular, it implements the ownership and
> > priority semantics for nbcon consoles. This series does _not_
> > include threaded printing, atomic printing regions, or nbcon
> > drivers. Those features will be added in separate follow-up
> > series.
> 
> This series seems to be ready for linux-next and I am going to
> push it.

JFYI, the patches has been pushed into printk/linux.git,
branch rework/nbcon-base.

Best Regards,
Petr