The majority of SMP platforms handle their IPIs through do_IRQ()
which calls irq_{enter/exit}(). When a call function IPI is received,
smp_call_function_interrupt() is called which also calls
irq_{enter,exit}(), meaning irq_count is raised twice.
When tick broadcasting is used (which is implemented via a call
function IPI), this incorrectly causes all CPU idle time on the core
receiving broadcast ticks to be accounted as time spent servicing
IRQs, as account_process_tick() will account as such if irq_count is
greater than 1. This results in 100% CPU usage being reported on a
core which receives its ticks via broadcast.
This patch removes the SMP smp_call_function_interrupt() wrapper which
calls irq_{enter,exit}(). Platforms which handle their IPIs through
do_IRQ() now call generic_smp_call_function_interrupt() directly to
avoid incrementing irq_count a second time. Platforms which don't
(loongson, sgi-ip27, sibyte) call generic_smp_call_function_interrupt()
wrapped in irq_{enter,exit}().
Signed-off-by: Alex Smith <alex.smith@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10770/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Pass 1 parts had a number of significant erratas and were only available
in small numbers and under NDA. Full support also required the use of a
special toolchain that kept branches properly aligned. These workarounds
were never upstreamed and the only toolchain known to have them is
Montavista's GCC 3.0-based toolchain which completly obsoleted if not
useless these days.
So now that automated testing has tripped over the user of the
-msb1-pass1-workarounds option, rather than fixing it remove support for
pass 1 parts.
Probably nobody will notice. I seem to own the last know pass 1 board
and I haven't noticed another one in the wild in the past decade, at
least.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Based on the spatch
@@
expression e;
@@
- return (e);
+ return e;
with heavy hand editing because some of the changes are either whitespace
or identation only or result in excessivly long lines.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Fixes the following randconfig build problem:
arch/mips/built-in.o: In function `show_cpuinfo':
proc.c:(.text+0xde84): undefined reference to `get_system_type'
arch/mips/built-in.o: In function `sb1250_setup':
(.init.text+0x428): undefined reference to `get_system_type'
arch/mips/built-in.o: In function `setup_arch':
(.init.text+0x178c): undefined reference to `plat_mem_setup'
Makefile:930: recipe for target 'vmlinux' failed
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8106/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Nothing was using the method and there isn't any need for this hook. This
leaves smp_cpus_done() empty for the moment.
As suggested by Paul Bolle <pebolle@tiscali.nl>.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
commit 3747069b25e419f6b51395f48127e9812abc3596 upstream.
The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications. For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.
After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out. Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.
Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
and are flagged as __cpuinit -- so if we remove the __cpuinit from
the arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
related content into no-ops as early as possible, since that will get
rid of these warnings. In any case, they are temporary and harmless.
Here, we remove all the MIPS __cpuinit from C code and __CPUINIT
from asm files. MIPS is interesting in this respect, because there
are also uasm users hiding behind their own renamed versions of the
__cpuinit macros.
[1] https://lkml.org/lkml/2013/5/20/589
[ralf@linux-mips.org: Folded in Paul's followup fix.]
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5494/
Patchwork: https://patchwork.linux-mips.org/patch/5495/
Patchwork: https://patchwork.linux-mips.org/patch/5509/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
CC arch/mips/sibyte/bcm1480/bus_watcher.o
CHK kernel/config_data.h
arch/mips/sibyte/bcm1480/bus_watcher.c: In function ‘check_bus_watcher’:
arch/mips/sibyte/bcm1480/bus_watcher.c:86:82: error: ‘A_SCD_BUS_ERR_STATUS_DEBUG’ undeclared (first use in this function)
arch/mips/sibyte/bcm1480/bus_watcher.c:86:82: note: each undeclared identifier is reported only once for each function it appears in
make[3]: *** [arch/mips/sibyte/bcm1480/bus_watcher.o] Error 1
make[2]: *** [arch/mips/sibyte/bcm1480] Error 2
make[1]: *** [arch/mips/sibyte] Error 2
make: *** [arch/mips] Error 2
The register moved around though it's otherwise the same but because of
the changed address it now also has a different name.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/5514/
Reported-by: Markos Chandras <markos.chandras@imgtec.com>
It's needed for the TASK_INTERRUPTIBLE definition.
Fixes the following build problem:
arch/mips/sibyte/common/sb_tbprof.c:235:4: error: 'TASK_INTERRUPTIBLE'
undeclared (first use in this function)
[ralf@linux-mips.org: Ideally sched.h should be included into the actual
user of TASK_INTERRUPTIBLE, <linux/wait.h> but that seems way too risky
that close to a release.]
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Acked-by: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: sibyte-users@bitmover.com
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5479/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Andreas Ruprecht
Ralf Baechle
Alex Smith
Markos Chandras
Paul Bolle
Thomas Gleixner
Maciej W. Rozycki
Paul Gortmaker
Al Viro