linux/arch/arm/kernel
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>
2016-10-07 18:46:30 -07:00
..
.gitignore
arch_timer.c arch_timer: Move to generic sched_clock framework 2013-10-09 16:54:10 -07:00
armksyms.c ARM: 8479/2: add implementation for arm-smccc 2016-01-04 16:24:34 +00:00
asm-offsets.c ARM: save and reset the address limit when entering an exception 2016-07-07 16:01:01 +01:00
atags_compat.c ARM: convert printk(KERN_* to pr_* 2014-11-21 15:24:50 +00:00
atags_parse.c ARM: convert printk(KERN_* to pr_* 2014-11-21 15:24:50 +00:00
atags_proc.c ARM: convert printk(KERN_* to pr_* 2014-11-21 15:24:50 +00:00
atags.h ARM: 8495/1: ATAGS: move save_atags() to arch/arm/include/asm/setup.h 2016-01-04 11:26:00 +00:00
bios32.c Merge branches 'pci/demodularize-hosts' and 'pci/host-request-windows' into next 2016-08-01 12:23:57 -05:00
calls.S ARM: wire up preadv2 and pwritev2 syscalls 2016-04-07 21:57:02 +01:00
cpuidle.c ARM: 8595/2: apply more __ro_after_init 2016-08-12 16:47:06 +01:00
crash_dump.c ARM: 8012/1: kdump: Avoid overflow when converting pfn to physaddr 2014-04-07 12:10:00 +01:00
debug.S ARM: unify MMU/!MMU addruart calls 2015-05-20 23:09:51 +02:00
devtree.c ARM: 8616/1: dt: Respect property size when parsing CPUs 2016-09-29 16:57:43 +01:00
dma-isa.c ARM: convert printk(KERN_* to pr_* 2014-11-21 15:24:50 +00:00
dma.c ARM: convert printk(KERN_* to pr_* 2014-11-21 15:24:50 +00:00
early_printk.c
efi.c ARM/efi: Apply strict permissions for UEFI Runtime Services regions 2016-04-28 11:33:53 +02:00
elf.c
entry-armv.S ARM: fix address limit restoration for undefined instructions 2016-08-09 22:57:59 +01:00
entry-common.S ARM: rename S_FRAME_SIZE to PT_REGS_SIZE 2016-06-22 19:54:28 +01:00
entry-ftrace.S ARM: replace BSYM() with badr assembly macro 2015-05-08 17:33:50 +01:00
entry-header.S ARM: save and reset the address limit when entering an exception 2016-07-07 16:01:01 +01:00
entry-v7m.S ARM: rename S_FRAME_SIZE to PT_REGS_SIZE 2016-06-22 19:54:28 +01:00
fiq.c ARM: convert printk(KERN_* to pr_* 2014-11-21 15:24:50 +00:00
fiqasm.S ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+ 2014-07-18 12:29:04 +01:00
ftrace.c ftrace: Add return address pointer to ftrace_ret_stack 2016-08-24 12:15:14 +02:00
head-common.S ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+ 2014-07-18 12:29:04 +01:00
head-nommu.S ARM: 8607/1: V7M: Wire up caches for V7M processors with cache support. 2016-09-06 15:51:08 +01:00
head.S Merge branch 'uaccess' into fixes 2015-09-11 19:18:28 +01:00
hibernate.c ARM: use virt_to_idmap() for soft_restart() 2016-02-08 15:48:32 +00:00
hw_breakpoint.c perf/core: Set event's default ::overflow_handler() 2016-03-31 10:30:47 +02:00
hyp-stub.S ARM: 8600/1: Enforce some NS-SVC initialisation 2016-08-23 10:08:33 +01:00
insn.c
io.c ARM: io.c: clean up EXPORT_SYMBOL()s 2014-11-21 15:25:02 +00:00
irq.c ARM: 8499/1: irq: l2c: do not print error in case of missing l2c from 2016-01-26 23:49:02 +00:00
isa.c arm: convert use of typedef ctl_table to struct ctl_table 2014-06-06 16:08:15 -07:00
iwmmxt.S ARM: 8221/1: PJ4: allow building in Thumb-2 mode 2014-12-03 16:08:00 +00:00
jump_label.c jump_label: Rename JUMP_LABEL_{EN,DIS}ABLE to JUMP_LABEL_{JMP,NOP} 2015-08-03 11:34:12 +02:00
kgdb.c ARM: 8428/1: kgdb: Fix registers on sleeping tasks 2015-10-03 16:36:45 +01:00
machine_kexec.c ARM: kexec: fix kexec for Keystone 2 2016-08-02 19:35:29 -04:00
Makefile ARM: 8534/1: virt: fix hyp-stub build for pre-ARMv7 CPUs 2016-02-22 11:39:41 +00:00
module-plts.c ARM: kernel: avoid brute force search on PLT generation 2016-08-30 17:45:34 +01:00
module.c ARM: 8518/1: Use correct symbols for XIP_KERNEL 2016-02-11 15:43:14 +00:00
module.lds ARM: kernel: merge core and init PLTs 2016-08-30 17:45:34 +01:00
opcodes.c
paravirt.c arm: introduce CONFIG_PARAVIRT, PARAVIRT_TIME_ACCOUNTING and pv_time_ops 2015-12-21 14:40:54 +00:00
patch.c ARM: probes: move all probe code to dedicate directory 2015-01-09 09:36:50 +00:00
perf_callchain.c perf core: Add a 'nr' field to perf_event_callchain_context 2016-05-16 23:11:51 -03:00
perf_event_v6.c arm: perf: factor arm_pmu core out to drivers 2015-07-31 15:01:14 +01:00
perf_event_v7.c arm: perf: move to common attr_group fields 2016-09-09 14:51:51 +01:00
perf_event_xscale.c arm: perf: factor arm_pmu core out to drivers 2015-07-31 15:01:14 +01:00
perf_regs.c perf: Move task_pt_regs sampling into arch code 2015-01-09 11:12:28 +01:00
pj4-cp0.c ARM: 8452/3: PJ4: make coprocessor access sequences buildable in Thumb2 mode 2016-01-04 11:12:10 +00:00
process.c ARM: save and reset the address limit when entering an exception 2016-07-07 16:01:01 +01:00
psci_smp.c ARM: use const and __initconst for smp_operations 2015-12-01 22:17:45 +01:00
ptrace.c arm/ptrace: run seccomp after ptrace 2016-06-14 10:54:42 -07:00
reboot.c ARM: 8568/1: reboot: remove duplicated local_irq_disable() 2016-05-05 19:02:09 +01:00
reboot.h ARM: move reboot code to arch/arm/kernel/reboot.c 2015-04-02 09:50:45 +01:00
relocate_kernel.S ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+ 2014-07-18 12:29:04 +01:00
return_address.c ARM: 8328/1: remove empty preprocessor #else branch 2015-03-28 16:54:53 +00:00
setup.c ARM: 8604/1: V7M: Add support for reading the CTR with read_cpuid_cachetype() 2016-09-06 15:51:07 +01:00
signal.c Merge branch 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm 2015-09-19 21:05:02 -07:00
sigreturn_codes.S ARM: 7895/1: signal: fix armv7-m build issue in sigreturn_codes.S 2013-11-30 22:21:00 +00:00
sleep.S ARM: fix new BSYM() usage introduced via for-arm-soc branch 2015-06-12 21:19:35 +01:00
smccc-call.S ARM: 8479/2: add implementation for arm-smccc 2016-01-04 16:24:34 +00:00
smp_scu.c ARM: 8122/1: smp_scu: enable SCU standby support 2014-08-02 08:51:53 +01:00
smp_tlb.c ARM: 8577/1: Fix Cortex-A15 798181 errata initialization 2016-07-02 12:13:03 +01:00
smp_twd.c arm/twd: Convert to hotplug state machine 2016-07-15 10:40:28 +02:00
smp.c nmi_backtrace: add more trigger_*_cpu_backtrace() methods 2016-10-07 18:46:30 -07:00
stacktrace.c ARM: 8172/1: Use current_stack_pointer in save_stack_trace_tsk 2014-11-13 23:58:03 +00:00
suspend.c ARM: 8248/1: pm: remove outdated comment 2015-01-21 15:58:57 +00:00
swp_emulate.c ARM: 8475/1: SWP emulation: Restore original *data when failed 2015-12-15 11:51:42 +00:00
sys_arm.c
sys_oabi-compat.c arm: oabi compat: add missing access checks 2016-08-10 12:57:45 -07:00
tcm.c ARM: 8388/1: tcm: Don't crash when TCM banks are protected by TrustZone 2015-06-06 10:37:28 +01:00
thumbee.c ARM: convert printk(KERN_* to pr_* 2014-11-21 15:24:50 +00:00
time.c clocksource: cosmetic: Drop OF 'dependency' from symbols 2015-10-01 02:18:39 +02:00
topology.c ARM: 8497/1: initialize cpu_scale to its default 2016-01-26 23:49:02 +00:00
traps.c ARM: remove user cmpxchg syscall 2015-10-03 16:36:45 +01:00
unwind.c ARM: 8176/1: Use current_stack_pointer in unwind_backtrace 2014-11-13 23:58:09 +00:00
v7m.c ARM: 7828/1: ARMv7-M: implement restart routine common to all v7-M machines 2013-09-02 13:49:29 +01:00
vdso.c Merge branch 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm 2016-10-06 07:59:37 -07:00
vmlinux-xip.lds.S ARM: 8537/1: drop unused DEBUG_RODATA from XIP_KERNEL 2016-02-22 11:39:43 +00:00
vmlinux.lds.S arm: jump label may reference text in __exit 2016-08-04 08:50:07 -04:00
xscale-cp0.c ARM: make xscale iwmmxt code multiplatform aware 2015-12-01 21:44:24 +01:00