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>
The debugging function dbg_chk_lpt_sz() was not working
correctly for small min_io_unit size e.g. NOR flash.
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
The function to traverse and dirty the LPT was still not
dirtying all nodes, with the result that the LPT could
run out of space.
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
These are mostly long lines and wrong indentation warning
fixes. But also there are two volatile variables and
checkpatch.pl complains about them:
WARNING: Use of volatile is usually wrong: see Documentation/volatile-considered-harmful.txt
+ volatile int gc_seq;
WARNING: Use of volatile is usually wrong: see Documentation/volatile-considered-harmful.txt
+ volatile int gced_lnum;
Well, we anyway use smp_wmb() for c->gc_seq and c->gced_lnum, so
these 'volatile' modifiers can be just dropped.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Do not forget to check whether lpt debugging is enabled before
running the check functions. This commit also makes some spelling
fixes.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Introduce a new data structure which contains all debugging
stuff inside. This is cleaner than having debugging stuff
directly in 'c'.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
The LPT may have gaps in it because initially empty LEBs
are not added by mkfs.ubifs - because it does not know how
many there are. Then UBIFS allocates empty LEBs in the
reverse order that they are discovered i.e. they are
added to, and removed from, the front of a list. That
creates a gap in the middle of the LPT.
The function dirtying the LPT tree (for the purpose of
small model garbage collection) assumed that a gap could
only occur at the very end of the LPT and stopped dirtying
prematurely, which in turn resulted in the LPT running
out of space - something that is designed to be impossible.
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Also add debugging checks for LPT size and separate
out c->check_lpt_free from unrelated bitfields.
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
This is a new flash file system. See
http://www.linux-mtd.infradead.org/doc/ubifs.html
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
