percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
This functions are implicitly called by core functions like cpu_relax(),
and since those functions may be called early on before common code has
initialized the per-cpu data area, we need to tweak the stats gathering.
Now the statistics are maintained in common bss which makes these funcs
safe to use as soon as the C runtime env is setup.
Signed-off-by: Graf Yang <graf.yang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
SMP systems require per-cpu local clock event devices in order to enable
HRT support. One a BF561, we can use local core timer for this purpose.
Originally, there was one global core-timer clock event device set up for
core A.
To accomplish this feat, we need to split the gptimer0/core timer logic
so that each is a standalone clock event. There is no requirement that
we only have one clock event source anyways. Once we have this, we just
define per-cpu clock event devices for each local core timer.
Signed-off-by: Yi Li <yi.li@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Sometimes a SMP system will randomly panic at boot. This is due to caches
being out of sync when one core tries to signal the other. So when one
core calls another via IPI, flush the data caches.
Signed-off-by: Yi Li <yi.li@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
When testing PREEMPT_RT kernel on BF561-EZKit, the kernel blocks while
booting. When the kernel initializes the ethernet driver, it sleeps and
never wakes up.
The issue happens when the kernel waits for a timer for Core B to timeout
(the timers are per-cpu based: static DEFINE_PER_CPU(struct tvec_base *,
tvec_bases) = &boot_tvec_bases).
However, the ksoftirqd thread for Core B (note, the ksoftirqd thread is
also per-cpu based) cannot work properly, and the timers for Core B never
times out.
When ksoftirqd() for the first time runs on core B, it is possible core A
is still initializing core B (see smp_init() -> cpu_up() -> __cpu_up()).
So the "cpu_is_offline()" check may return true and ksoftirqd moves to
"wait_to_die".
So delay the core b start up until the per-cpu timers have been set up
fully.
Signed-off-by: Yi Li <yi.li@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
To set zeroes the sizeof the struct should be used rather
than sizeof the pointer, kzalloc does that.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Bill Gatliff & David Brownell pointed out we were missing some
copyrights, and licensing terms in some of the files in
./arch/blackfin, so this fixes things, and cleans them up.
It also removes:
- verbose GPL text(refer to the top level ./COPYING file)
- file names (you are looking at the file)
- bug url (it's in the ./MAINTAINERS file)
- "or later" on GPL-2, when we did not have that right
It also allows some Blackfin-specific assembly files to be under a BSD
like license (for people to use them outside of Linux).
Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Check that the result of kmalloc is not NULL before passing it to other
functions.
In the first two cases, the new code returns -ENOMEM, which seems
compatible with what is done for similar functions for other architectures.
In the last two cases, the new code fails silently, ie just returns,
because the function has void return type.
The semantic match that finds this problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@@
expression *x;
identifier f;
constant char *C;
@@
x = \(kmalloc\|kcalloc\|kzalloc\)(...);
... when != x == NULL
when != x != NULL
when != (x || ...)
(
kfree(x)
|
f(...,C,...,x,...)
|
*f(...,x,...)
|
*x->f
)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
On Blackfin SMP, a per-cpu loops_per_jiffy is pointless since both cores
always run at the same CCLK. In addition, the current implementation has
flaws since the main consumer for loops_per_jiffy (asm/delay.h) uses the
global kernel loops_per_jiffy and not the per_cpu one. So punt all of the
per-cpu handling and go back to the global shared one.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
When a low priority interrupt (like ethernet) is triggered between 2 high
priority IPI messages, a deadlock in disable_irq() is hit by the second
IPI handler. This is because the second IPI message is queued within the
first IPI handler, but the handler doesn't process all messages, and new
ones are inserted rather than appended. So now we process all the pending
messages, and append new ones to the pending list.
URL: http://blackfin.uclinux.org/gf/tracker/5226
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
The KGDB code uses this when switching processors to make sure the icache
is in a valid state.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
The Per-processor Data Area isn't actually reserved by this function, and
all it ended up doing was issuing a printk(), so punt it.
Signed-off-by: Graf Yang <graf.yang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
For systems where the core cycles are not a usable tick source (like SMP
or cycles gets updated), enable gptimer0 as an alternative.
Signed-off-by: Graf Yang <graf.yang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Add some notes for anomaly 05000120 to make sure we work around it.
Signed-off-by: Graf Yang <graf.yang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
[Mike Frysinger <vapier.adi@gmail.com>:
- handle bf531/bf532/bf534/bf536 variants in ipipe.h
- cleanup IPIPE logic for bfin_set_irq_handler()
- cleanup ipipe asm code a bit and add missing ENDPROC()
- simplify IPIPE code in trap_c
- unify some of the IPIPE code and fix style
- simplify DO_IRQ_L1 handling with ipipe code
- revert IRQ_SW_INT# addition from ipipe merge
- remove duplicate get_{c,s}clk() prototypes
]
Signed-off-by: Yi Li <yi.li@analog.com>
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
rename irq_flags to bfin_irq_flags to avoid namespace
collision with common code
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Blackfin dual core BF561 processor can support SMP like features.
https://docs.blackfin.uclinux.org/doku.php?id=linux-kernel:smp-like
In this patch, we provide SMP extend to Blackfin header files
and machine common code
Signed-off-by: Graf Yang <graf.yang@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
