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Paul Burton 97c8580e85
MIPS: Annotate cpu_wait implementations with __cpuidle
Annotate cpu_wait implementations using the __cpuidle macro which
places these functions in the .cpuidle.text section. This allows
cpu_in_idle() to return true for PC values which fall within these
functions, allowing nmi_backtrace() to produce cleaner output for CPUs
running idle functions. For example:

  # echo l >/proc/sysrq-trigger
  [   38.587170] sysrq: SysRq : Show backtrace of all active CPUs
  [   38.593657] NMI backtrace for cpu 1
  [   38.597611] CPU: 1 PID: 161 Comm: sh Not tainted 4.18.0-rc1+ #27
  [   38.604306] Stack : 00000000 00000004 00000006 80486724 00000000 00000000 00000000 00000000
  [   38.613647]         80e17eda 00000034 00000000 00000000 80d20000 80b67e98 8e559c90 0ffe1e88
  [   38.622986]         00000000 00000000 80e70000 00000000 8f61db18 38312e34 722d302e 202b3163
  [   38.632324]         8e559d3c 8e559adc 00000001 6b636162 80d20000 80000000 00000000 80d1cfa4
  [   38.641664]         00000001 80d20000 80d19520 00000000 00000003 80836724 00000004 80e10004
  [   38.650993]         ...
  [   38.653724] Call Trace:
  [   38.656499] [<8040cdd0>] show_stack+0xa0/0x144
  [   38.661475] [<80b67e98>] dump_stack+0xe8/0x120
  [   38.666455] [<80b6f6d4>] nmi_cpu_backtrace+0x1b4/0x1cc
  [   38.672189] [<80b6f81c>] nmi_trigger_cpumask_backtrace+0x130/0x1e4
  [   38.679081] [<808295d8>] __handle_sysrq+0xc0/0x180
  [   38.684421] [<80829b84>] write_sysrq_trigger+0x50/0x64
  [   38.690176] [<8061c984>] proc_reg_write+0xd0/0xfc
  [   38.695447] [<805aac1c>] __vfs_write+0x54/0x194
  [   38.700500] [<805aaf24>] vfs_write+0xe0/0x18c
  [   38.705360] [<805ab190>] ksys_write+0x7c/0xf0
  [   38.710238] [<80416018>] syscall_common+0x34/0x58
  [   38.715558] Sending NMI from CPU 1 to CPUs 0,2-3:
  [   38.720916] NMI backtrace for cpu 0 skipped: idling at r4k_wait_irqoff+0x2c/0x34
  [   38.729186] NMI backtrace for cpu 3 skipped: idling at r4k_wait_irqoff+0x2c/0x34
  [   38.737449] NMI backtrace for cpu 2 skipped: idling at r4k_wait_irqoff+0x2c/0x34

Without this we get register value & backtrace output from all CPUs,
which is generally useless for those running the idle function & serves
only to overwhelm & obfuscate the meaningful output from non-idle CPUs.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/19598/
2018-06-28 14:18:54 -07:00
arch MIPS: Annotate cpu_wait implementations with __cpuidle 2018-06-28 14:18:54 -07:00
block for-linus-20180623 2018-06-24 06:33:54 +08:00
certs docs: Fix some broken references 2018-06-15 18:10:01 -03:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2018-06-24 06:31:54 +08:00
Documentation This contains a few fixes and a clean up. 2018-06-24 06:23:28 +08:00
drivers Merge branch 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-06-24 20:16:17 +08:00
firmware kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
fs \n 2018-06-22 18:04:56 +09:00
include dma-noncoherent: add a arch_sync_dma_for_cpu_all hook 2018-06-24 09:27:27 -07:00
init dma-mapping: move all DMA mapping code to kernel/dma 2018-06-14 08:50:37 +02:00
ipc ipc: use new return type vm_fault_t 2018-06-15 07:55:25 +09:00
kernel dma-noncoherent: add a arch_sync_dma_for_cpu_all hook 2018-06-24 09:27:27 -07:00
lib Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-06-24 19:36:16 +08:00
LICENSES LICENSES: Add Linux-OpenIB license text 2018-04-27 16:41:53 -06:00
mm for-linus-20180623 2018-06-24 06:33:54 +08:00
net NFS client bugfixes for Linux 4.18 2018-06-22 06:21:34 +09:00
samples VFIO updates for v4.18 2018-06-12 13:11:26 -07:00
scripts tracing: Fix SKIP_STACK_VALIDATION=1 build due to bad merge with -mrecord-mcount 2018-06-21 15:12:56 -04:00
security docs: Fix some broken references 2018-06-15 18:10:01 -03:00
sound docs: Fix some broken references 2018-06-15 18:10:01 -03:00
tools Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-06-24 20:29:15 +08:00
usr kbuild: rename built-in.o to built-in.a 2018-03-26 02:01:19 +09:00
virt KVM: arm64: Prevent KVM_COMPAT from being selected 2018-06-21 17:17:50 +01:00
.clang-format clang-format: add configuration file 2018-04-11 10:28:35 -07:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap Merge branch 'asoc-4.17' into asoc-4.18 for compress dependencies 2018-04-26 12:24:28 +01:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS MAINTAINERS/CREDITS: Drop METAG ARCHITECTURE 2018-03-05 16:34:24 +00:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: add basic helper macros to scripts/Kconfig.include 2018-05-29 03:31:19 +09:00
MAINTAINERS Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-06-24 19:59:52 +08:00
Makefile Linux 4.18-rc2 2018-06-24 20:54:29 +08:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.