From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: John Ogness Subject: [PATCH next v3 00/15] printk: remove logbuf_lock Date: Thu, 25 Feb 2021 21:24:23 +0100 Message-Id: <20210225202438.28985-1-john.ogness@linutronix.de> MIME-Version: 1.0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-um" Errors-To: linux-um-bounces+geert=linux-m68k.org@lists.infradead.org To: Petr Mladek Cc: linux-hyperv@vger.kernel.org, Sergey Senozhatsky , Vignesh Raghavendra , Benjamin Herrenschmidt , Douglas Anderson , linux-mtd@lists.infradead.org, Michael Ellerman , Miquel Raynal , "K. Y. Srinivasan" , Thomas Meyer , Kees Cook , Daniel Thompson , Madhavan Srinivasan , Stephen Hemminger , Richard Weinberger , Anton Vorontsov , Joel Stanley , Jordan Niethe , Anton Ivanov , Wei Li , Haiyang Zhang , Ravi Bangoria , Pavel Tatashin , Alistair Popple , Jeff Dike , Colin Cross , linux-um@lists.infradead.org, Wei Liu , Steven Rostedt , Davidlohr Bueso , Nicholas Piggin , Oleg Nesterov , Thomas Gleixner , Andy Shevchenko , Michael Kelley , Christophe Leroy , Sumit Garg , Tony Luck , linux-kernel@vger.kernel.org, Sergey Senozhatsky , Jason Wessel , kgdb-bugreport@lists.sourceforge.net, Paul Mackerras , linuxppc-dev@lists.ozlabs.org, Mike Rapoport Hello, Here is v3 of a series to remove @logbuf_lock, exposing the ringbuffer locklessly to both readers and writers. v2 is here [0]. Since @logbuf_lock was protecting much more than just the ringbuffer, this series clarifies and cleans up the various protections using comments, lockless accessors, atomic types, and a new finer-grained @syslog_lock. Removing @logbuf_lock required changing the semantics of the kmsg_dumper callback in order to work locklessly. Since this involved touching all the kmsg_dump users, we also decided [1] to use this opportunity to clean up and clarify the kmsg_dump semantics in general. This series is based on next-20210225. Changes since v2: - use get_maintainer.pl to get the full list of developers that should at least see the changes in their respective areas - do not disable interrupts in arch/um kmsg_dumper (because there is no need to) - protect the mtd/mtdoops kmsg_dumper buffer against concurrent dumps - update kerneldoc for kmsg_dump_get_line() (@len_out) - remove ksmg_dump's @active flag - change kmsg_dumper callback to: void (*dump)(enum kmsg_dump_reason reason); - rename kmsg_dumper_iter to kmsg_dump_iter - update kmsg_dumpers to use their own kmsg_dump_iter (and initialize it with kmsg_dump_rewind() if necessary) John Ogness [0] https://lkml.kernel.org/r/20210218081817.28849-1-john.ogness@linutronix.de [1] https://lkml.kernel.org/r/YDeZAA08NKCHa4s%2F@alley John Ogness (15): um: synchronize kmsg_dumper mtd: mtdoops: synchronize kmsg_dumper printk: limit second loop of syslog_print_all printk: kmsg_dump: remove unused fields printk: refactor kmsg_dump_get_buffer() printk: consolidate kmsg_dump_get_buffer/syslog_print_all code printk: introduce CONSOLE_LOG_MAX for improved multi-line support printk: use seqcount_latch for clear_seq printk: use atomic64_t for devkmsg_user.seq printk: add syslog_lock printk: kmsg_dumper: remove @active field printk: introduce a kmsg_dump iterator printk: remove logbuf_lock printk: kmsg_dump: remove _nolock() variants printk: console: remove unnecessary safe buffer usage arch/powerpc/kernel/nvram_64.c | 14 +- arch/powerpc/platforms/powernv/opal-kmsg.c | 3 +- arch/powerpc/xmon/xmon.c | 6 +- arch/um/kernel/kmsg_dump.c | 15 +- drivers/hv/vmbus_drv.c | 7 +- drivers/mtd/mtdoops.c | 20 +- fs/pstore/platform.c | 8 +- include/linux/kmsg_dump.h | 49 +-- kernel/debug/kdb/kdb_main.c | 10 +- kernel/printk/internal.h | 4 +- kernel/printk/printk.c | 456 ++++++++++----------- kernel/printk/printk_safe.c | 27 +- 12 files changed, 309 insertions(+), 310 deletions(-) -- 2.20.1 _______________________________________________ linux-um mailing list linux-um@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-um