linux/include
Chris Metcalf 9a01c3ed5c nmi_backtrace: add more trigger_*_cpu_backtrace() methods
Patch series "improvements to the nmi_backtrace code" v9.

This patch series modifies the trigger_xxx_backtrace() NMI-based remote
backtracing code to make it more flexible, and makes a few small
improvements along the way.

The motivation comes from the task isolation code, where there are
scenarios where we want to be able to diagnose a case where some cpu is
about to interrupt a task-isolated cpu.  It can be helpful to see both
where the interrupting cpu is, and also an approximation of where the
cpu that is being interrupted is.  The nmi_backtrace framework allows us
to discover the stack of the interrupted cpu.

I've tested that the change works as desired on tile, and build-tested
x86, arm, mips, and sparc64.  For x86 I confirmed that the generic
cpuidle stuff as well as the architecture-specific routines are in the
new cpuidle section.  For arm, mips, and sparc I just build-tested it
and made sure the generic cpuidle routines were in the new cpuidle
section, but I didn't attempt to figure out which the platform-specific
idle routines might be.  That might be more usefully done by someone
with platform experience in follow-up patches.

This patch (of 4):

Currently you can only request a backtrace of either all cpus, or all
cpus but yourself.  It can also be helpful to request a remote backtrace
of a single cpu, and since we want that, the logical extension is to
support a cpumask as the underlying primitive.

This change modifies the existing lib/nmi_backtrace.c code to take a
cpumask as its basic primitive, and modifies the linux/nmi.h code to use
the new "cpumask" method instead.

The existing clients of nmi_backtrace (arm and x86) are converted to
using the new cpumask approach in this change.

The other users of the backtracing API (sparc64 and mips) are converted
to use the cpumask approach rather than the all/allbutself approach.
The mips code ignored the "include_self" boolean but with this change it
will now also dump a local backtrace if requested.

Link: http://lkml.kernel.org/r/1472487169-14923-2-git-send-email-cmetcalf@mellanox.com
Signed-off-by: Chris Metcalf <cmetcalf@mellanox.com>
Tested-by: Daniel Thompson <daniel.thompson@linaro.org> [arm]
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
History 2016-10-07 18:46:30 -07:00
..
acpi Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-10-03 19:43:08 -07:00
asm-generic mm: move phys_mem_access_prot_allowed() declaration to pgtable.h 2016-10-07 18:46:29 -07:00
clocksource clocksource/drivers/sp804: Convert init function to return error 2016-06-28 10:19:30 +02:00
crypto A number of improvements for the /dev/random driver; the most 2016-07-27 15:11:55 -07:00
drm Merge branch 'drm-next-4.8' of git://people.freedesktop.org/~agd5f/linux into drm-next 2016-08-08 16:45:33 +10:00
dt-bindings - Core Frameworks 2016-10-07 08:35:35 -07:00
keys KEYS: Strip trailing spaces 2016-06-14 10:29:44 +01:00
kvm ARM: KVM: Support vgic-v3 2016-09-22 13:22:21 +02:00
linux nmi_backtrace: add more trigger_*_cpu_backtrace() methods 2016-10-07 18:46:30 -07:00
math-emu math-emu: fix floating-point to integer overflow detection 2014-01-07 18:36:24 -06:00
media [media] cec: rename cec_devnode fhs_lock to just lock 2016-08-22 13:09:06 -03:00
memory ddr: add LPDDR2 data from JESD209-2 2012-05-02 00:04:06 -07:00
misc cxl: Add cxl_check_and_switch_mode() API to switch bi-modal cards 2016-07-14 20:28:11 +10:00
net Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2016-10-06 09:52:23 -07:00
pcmcia pcmcia/ds.h: introduce helper for pcmcia_driver module boilerplate 2013-03-15 12:26:03 -07:00
ras tracing, RAS: Cleanup on __get_str() usage 2016-07-15 15:51:16 -04:00
rdma IB/core: Add ib headers for general use 2016-10-02 08:40:35 -04:00
rxrpc rxrpc: Add tracepoint for ACK proposal 2016-09-23 15:49:19 +01:00
scsi Merge remote-tracking branch 'mkp-scsi/4.8/scsi-fixes' into fixes 2016-09-27 22:30:51 -07:00
soc The core clk framework changes are small again. They're mostly minor fixes 2016-10-04 11:04:57 -07:00
sound ASoC: Updates for v4.9 2016-09-30 18:40:40 +02:00
target target: Fix ordered task CHECK_CONDITION early exception handling 2016-07-20 00:58:40 -07:00
trace mm, compaction: rename COMPACT_PARTIAL to COMPACT_SUCCESS 2016-10-07 18:46:27 -07:00
uapi Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid 2016-10-07 11:58:38 -07:00
video gpu: ipu-v3: ipu-dmfc: Use static DMFC FIFO allocation mechanism 2016-07-12 18:23:43 +02:00
xen xen: features and fixes for 4.9-rc0 2016-10-06 11:19:10 -07:00
Kbuild UAPI: remove empty Kbuild files 2013-04-30 17:04:09 -07:00