2008-01-29 14:53:40 +01:00
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2009-07-31 11:49:12 -04:00
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2010-03-15 12:46:51 +01:00
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2009-11-11 13:47:45 +01:00
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include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
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>
2010-03-24 17:04:11 +09:00
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2008-01-29 14:53:40 +01:00
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block: hook up writeback throttling
Enable throttling of buffered writeback to make it a lot
more smooth, and has way less impact on other system activity.
Background writeback should be, by definition, background
activity. The fact that we flush huge bundles of it at the time
means that it potentially has heavy impacts on foreground workloads,
which isn't ideal. We can't easily limit the sizes of writes that
we do, since that would impact file system layout in the presence
of delayed allocation. So just throttle back buffered writeback,
unless someone is waiting for it.
The algorithm for when to throttle takes its inspiration in the
CoDel networking scheduling algorithm. Like CoDel, blk-wb monitors
the minimum latencies of requests over a window of time. In that
window of time, if the minimum latency of any request exceeds a
given target, then a scale count is incremented and the queue depth
is shrunk. The next monitoring window is shrunk accordingly. Unlike
CoDel, if we hit a window that exhibits good behavior, then we
simply increment the scale count and re-calculate the limits for that
scale value. This prevents us from oscillating between a
close-to-ideal value and max all the time, instead remaining in the
windows where we get good behavior.
Unlike CoDel, blk-wb allows the scale count to to negative. This
happens if we primarily have writes going on. Unlike positive
scale counts, this doesn't change the size of the monitoring window.
When the heavy writers finish, blk-bw quickly snaps back to it's
stable state of a zero scale count.
The patch registers a sysfs entry, 'wb_lat_usec'. This sets the latency
target to me met. It defaults to 2 msec for non-rotational storage, and
75 msec for rotational storage. Setting this value to '0' disables
blk-wb. Generally, a user would not have to touch this setting.
We don't enable WBT on devices that are managed with CFQ, and have
a non-root block cgroup attached. If we have a proportional share setup
on this particular disk, then the wbt throttling will interfere with
that. We don't have a strong need for wbt for that case, since we will
rely on CFQ doing that for us.
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-09 12:38:14 -07:00
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2008-01-29 14:53:40 +01:00
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2008-01-31 13:03:55 +01:00
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2008-01-29 14:53:40 +01:00
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2008-01-31 13:03:55 +01:00
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2008-01-29 14:53:40 +01:00
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2010-07-01 19:49:17 +09:00
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2008-01-29 14:53:40 +01:00
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2008-09-14 05:55:09 -07:00
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2017-08-23 10:56:29 -07:00
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2008-09-14 05:55:09 -07:00
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2008-10-01 16:12:15 +02:00
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2009-06-16 08:23:52 +02:00
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2009-06-19 09:18:32 +02:00
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2009-06-16 08:23:52 +02:00
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2012-01-11 16:27:11 +01:00
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2009-06-16 08:23:52 +02:00
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2010-02-26 00:20:39 -05:00
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2017-02-08 14:46:49 +01:00
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2010-09-10 20:50:10 +02:00
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2009-06-16 08:23:52 +02:00
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2015-08-19 14:24:05 -07:00
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2010-02-26 00:20:37 -05:00
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2016-02-10 16:52:47 -07:00
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2014-06-05 13:38:39 -06:00
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2012-09-18 12:19:27 -04:00
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2016-11-30 12:28:59 -08:00
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2009-11-10 11:50:21 +01:00
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2015-07-16 09:14:26 -06:00
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2009-11-10 11:50:21 +01:00
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2009-06-16 08:23:52 +02:00
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2009-06-18 09:56:03 +02:00
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2009-06-16 08:23:52 +02:00
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2010-12-01 19:41:49 +01:00
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2016-10-18 15:40:29 +09:00
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2009-06-16 08:23:52 +02:00
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2012-01-11 16:27:11 +01:00
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2017-02-08 14:46:49 +01:00
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2012-01-11 16:27:11 +01:00
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2013-10-18 09:44:49 -06:00
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2012-08-01 10:44:28 +02:00
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2015-11-13 16:46:48 -05:00
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2012-09-18 12:19:27 -04:00
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2016-11-30 12:28:59 -08:00
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2012-01-11 16:27:11 +01:00
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2008-01-29 14:53:40 +01:00
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2017-11-08 19:13:48 +01:00
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2008-01-29 14:53:40 +01:00
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2008-01-31 13:03:55 +01:00
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2008-01-29 14:53:40 +01:00
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2008-12-03 12:55:08 +01:00
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2008-01-29 14:53:40 +01:00
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2009-06-16 08:23:52 +02:00
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2008-01-29 14:53:40 +01:00
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2009-04-15 22:10:25 +09:00
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2013-07-29 14:17:54 +01:00
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2008-01-29 14:53:40 +01:00
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2013-07-29 14:17:54 +01:00
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2008-01-29 14:53:40 +01:00
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2013-07-29 14:17:54 +01:00
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2008-01-29 14:53:40 +01:00
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2013-07-29 14:17:54 +01:00
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2008-01-29 14:53:40 +01:00
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2009-04-15 22:10:25 +09:00
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2008-01-29 14:53:40 +01:00
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2010-10-01 14:45:27 +02:00
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2008-01-29 14:53:40 +01:00
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2008-01-31 13:03:55 +01:00
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2008-01-29 14:53:40 +01:00
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2010-09-24 20:25:49 +02:00
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2010-10-01 14:42:43 +02:00
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2008-01-29 14:53:40 +01:00
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2010-10-01 14:42:43 +02:00
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2008-01-29 14:53:40 +01:00
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2015-11-13 16:46:48 -05:00
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2010-02-26 00:20:35 -05:00
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2008-01-29 14:53:40 +01:00
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2010-02-26 00:20:35 -05:00
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2015-06-23 12:13:59 -04:00
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2010-02-26 00:20:35 -05:00
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2015-11-13 16:46:48 -05:00
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2010-02-26 00:20:35 -05:00
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2008-01-29 14:53:40 +01:00
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2015-11-13 16:46:48 -05:00
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2008-01-29 14:53:40 +01:00
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2015-11-13 16:46:48 -05:00
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mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.
This promise never materialized. And unlikely will.
We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE. And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.
Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.
Let's stop pretending that pages in page cache are special. They are
not.
The changes are pretty straight-forward:
- <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
- <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
- PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};
- page_cache_get() -> get_page();
- page_cache_release() -> put_page();
This patch contains automated changes generated with coccinelle using
script below. For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.
The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.
There are few places in the code where coccinelle didn't reach. I'll
fix them manually in a separate patch. Comments and documentation also
will be addressed with the separate patch.
virtual patch
@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E
@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E
@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT
@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE
@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK
@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)
@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)
@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
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2008-05-01 04:35:17 -07:00
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2010-02-26 00:20:35 -05:00
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2008-01-29 14:53:40 +01:00
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2015-08-13 14:57:56 -04:00
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2015-11-13 16:46:48 -05:00
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2017-02-02 15:56:50 +01:00
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2008-01-29 14:53:40 +01:00
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2010-02-26 00:20:38 -05:00
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2008-01-29 14:53:40 +01:00
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2014-06-05 13:38:39 -06:00
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2014-06-10 12:53:56 -06:00
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2014-06-05 13:38:39 -06:00
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2009-09-30 13:54:20 +02:00
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2009-10-12 08:20:47 +02:00
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2009-09-30 13:54:20 +02:00
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2015-07-16 09:14:26 -06:00
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2009-09-30 13:54:20 +02:00
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2012-09-18 12:19:27 -04:00
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2016-11-30 12:28:59 -08:00
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2008-01-29 14:53:40 +01:00
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2010-02-26 00:20:39 -05:00
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2008-01-29 14:53:40 +01:00
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2010-02-26 00:20:39 -05:00
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2008-01-29 14:53:40 +01:00
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2010-02-26 00:20:39 -05:00
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2008-01-29 14:53:40 +01:00
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2008-05-01 04:35:17 -07:00
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2008-01-29 14:53:40 +01:00
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2010-02-26 00:20:39 -05:00
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2008-01-29 14:53:40 +01:00
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2010-02-26 00:20:39 -05:00
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2008-01-29 14:53:40 +01:00
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2017-02-08 14:46:49 +01:00
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2008-01-29 14:53:40 +01:00
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mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.
This promise never materialized. And unlikely will.
We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE. And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.
Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.
Let's stop pretending that pages in page cache are special. They are
not.
The changes are pretty straight-forward:
- <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
- <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
- PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};
- page_cache_get() -> get_page();
- page_cache_release() -> put_page();
This patch contains automated changes generated with coccinelle using
script below. For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.
The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.
There are few places in the code where coccinelle didn't reach. I'll
fix them manually in a separate patch. Comments and documentation also
will be addressed with the separate patch.
virtual patch
@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E
@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E
@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT
@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE
@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK
@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)
@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)
@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
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2008-05-01 04:35:17 -07:00
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2008-01-29 14:53:40 +01:00
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2009-05-22 17:17:51 -04:00
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2008-01-29 14:53:40 +01:00
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2009-05-22 17:17:49 -04:00
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2008-01-29 14:53:40 +01:00
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2009-05-22 17:17:49 -04:00
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2008-01-29 14:53:40 +01:00
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2009-05-22 17:17:49 -04:00
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2008-01-29 14:53:40 +01:00
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2009-05-22 17:17:49 -04:00
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2008-01-29 14:53:40 +01:00
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2009-05-22 17:17:51 -04:00
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2009-05-22 17:17:53 -04:00
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2008-01-29 14:53:40 +01:00
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2009-05-22 17:17:49 -04:00
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2008-01-29 14:53:40 +01:00
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2009-05-22 17:17:53 -04:00
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2010-10-13 21:18:03 +02:00
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2009-05-22 17:17:53 -04:00
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2009-06-11 20:00:41 -07:00
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2009-05-22 17:17:53 -04:00
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2009-07-31 11:49:11 -04:00
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2009-05-22 17:17:53 -04:00
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2009-06-11 20:00:41 -07:00
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2009-05-22 17:17:53 -04:00
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2009-07-31 11:49:13 -04:00
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2009-05-22 17:17:53 -04:00
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2009-07-31 11:49:11 -04:00
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2009-05-22 17:17:53 -04:00
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2009-09-11 21:54:52 +02:00
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2009-05-22 17:17:53 -04:00
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2009-06-11 20:00:41 -07:00
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2009-05-22 17:17:53 -04:00
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2009-07-31 11:49:13 -04:00
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2009-05-22 17:17:53 -04:00
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2009-09-11 21:54:52 +02:00
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2009-05-22 17:17:53 -04:00
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2008-01-29 14:53:40 +01:00
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2009-07-31 11:49:10 -04:00
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2008-01-29 14:53:40 +01:00
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2009-05-22 17:17:53 -04:00
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2009-12-29 08:35:35 +01:00
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2010-01-11 03:21:51 -05:00
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2009-05-22 17:17:53 -04:00
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2009-12-29 08:35:35 +01:00
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2009-05-22 17:17:53 -04:00
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2010-01-11 03:21:51 -05:00
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2009-05-22 17:17:53 -04:00
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2010-01-11 03:21:51 -05:00
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2009-11-10 11:50:21 +01:00
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2009-05-22 17:17:53 -04:00
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2015-11-13 16:46:48 -05:00
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2012-09-18 12:19:27 -04:00
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2016-11-30 12:28:59 -08:00
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2009-06-09 06:23:22 +02:00
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2009-05-22 17:17:53 -04:00
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2015-08-19 14:24:05 -07:00
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2009-05-22 17:17:53 -04:00
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2010-02-26 00:20:39 -05:00
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2017-02-08 14:46:49 +01:00
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2010-09-10 20:50:10 +02:00
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2009-05-22 17:17:53 -04:00
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2010-01-11 03:21:47 -05:00
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2010-01-11 03:21:51 -05:00
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2009-12-21 15:55:51 +01:00
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2009-12-29 08:35:35 +01:00
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2009-12-21 15:55:51 +01:00
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2009-12-29 08:35:35 +01:00
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2009-12-21 15:55:51 +01:00
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2009-12-29 08:35:35 +01:00
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2014-10-08 18:26:13 -04:00
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2009-12-21 15:55:51 +01:00
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2010-01-11 03:21:47 -05:00
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2009-12-21 15:55:51 +01:00
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2009-05-22 17:17:53 -04:00
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2015-03-30 13:39:09 -04:00
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2009-12-21 15:55:51 +01:00
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2010-12-01 19:41:49 +01:00
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2009-05-22 17:17:53 -04:00
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2009-12-29 08:35:35 +01:00
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2009-12-21 15:55:51 +01:00
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2009-05-22 17:17:53 -04:00
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2010-01-11 03:21:47 -05:00
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2009-11-10 11:50:21 +01:00
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2009-12-29 08:35:35 +01:00
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2009-12-21 15:55:51 +01:00
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2010-01-11 03:21:47 -05:00
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2009-05-22 17:17:53 -04:00
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2009-12-29 08:35:35 +01:00
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2009-12-21 15:55:51 +01:00
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2010-01-11 03:21:47 -05:00
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2009-12-21 15:55:51 +01:00
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2009-05-22 17:17:53 -04:00
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2013-07-11 22:39:53 -07:00
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2009-12-29 08:35:35 +01:00
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2015-03-30 13:39:09 -04:00
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2014-10-08 18:26:13 -04:00
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2009-11-10 11:50:21 +01:00
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2009-12-29 08:35:35 +01:00
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2010-01-11 03:21:47 -05:00
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2009-05-22 17:17:53 -04:00
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2010-01-11 03:21:47 -05:00
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2009-05-22 17:17:53 -04:00
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2009-12-21 15:55:51 +01:00
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2010-01-11 03:21:51 -05:00
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2009-12-21 15:55:51 +01:00
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2009-07-31 11:49:12 -04:00
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2009-12-21 15:55:51 +01:00
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2012-12-14 11:15:36 +08:00
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2009-12-21 15:55:51 +01:00
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2009-12-29 08:35:35 +01:00
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2015-07-16 09:14:26 -06:00
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2009-12-21 15:55:51 +01:00
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2015-03-30 13:39:09 -04:00
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2012-12-14 11:15:36 +08:00
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2009-12-21 15:55:51 +01:00
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2009-07-31 11:49:12 -04:00
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2016-10-18 15:40:31 +09:00
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2010-01-11 03:21:47 -05:00
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2009-05-22 17:17:53 -04:00
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2009-05-28 11:04:53 +02:00
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2009-05-22 17:17:53 -04:00
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2010-01-11 03:21:49 -05:00
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2010-01-11 03:21:51 -05:00
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2010-01-11 03:21:49 -05:00
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2009-05-22 17:17:53 -04:00
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2009-06-09 06:23:22 +02:00
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2009-05-22 17:17:53 -04:00
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2010-01-11 03:21:51 -05:00
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2009-05-22 17:17:53 -04:00
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2010-01-11 03:21:51 -05:00
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2009-05-22 17:17:53 -04:00
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2008-03-04 11:18:17 +01:00
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2008-07-04 09:30:03 +02:00
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2008-03-04 11:18:17 +01:00
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2008-07-04 09:30:03 +02:00
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2008-03-04 11:18:17 +01:00
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2008-07-04 09:30:03 +02:00
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2008-01-29 14:53:40 +01:00
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2008-02-19 11:36:53 +01:00
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2008-01-29 14:53:40 +01:00
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2010-02-26 00:20:39 -05:00
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2008-01-29 14:53:40 +01:00
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2008-03-04 11:30:18 +01:00
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2008-02-19 11:36:53 +01:00
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2008-01-29 14:53:40 +01:00
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2010-02-26 00:20:39 -05:00
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2008-01-29 14:53:40 +01:00
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2010-02-26 00:20:39 -05:00
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2008-02-19 11:36:53 +01:00
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2008-01-29 14:53:40 +01:00
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mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.
This promise never materialized. And unlikely will.
We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE. And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.
Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.
Let's stop pretending that pages in page cache are special. They are
not.
The changes are pretty straight-forward:
- <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
- <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
- PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};
- page_cache_get() -> get_page();
- page_cache_release() -> put_page();
This patch contains automated changes generated with coccinelle using
script below. For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.
The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.
There are few places in the code where coccinelle didn't reach. I'll
fix them manually in a separate patch. Comments and documentation also
will be addressed with the separate patch.
virtual patch
@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E
@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E
@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT
@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE
@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK
@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)
@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)
@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
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2008-05-01 04:35:17 -07:00
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2008-01-29 14:53:40 +01:00
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2009-05-22 17:17:51 -04:00
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2008-01-29 14:53:40 +01:00
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2015-08-19 14:24:05 -07:00
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2008-01-29 14:53:40 +01:00
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2008-08-19 20:13:11 +02:00
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2009-04-01 15:01:39 +01:00
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2008-01-29 14:53:40 +01:00
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2008-08-19 20:13:11 +02:00
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2008-01-29 14:53:40 +01:00
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2011-05-06 11:34:32 -06:00
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2016-04-13 13:33:19 -06:00
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2018-03-07 17:10:04 -08:00
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2016-04-13 13:33:19 -06:00
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2018-03-07 17:10:04 -08:00
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2011-05-06 11:34:32 -06:00
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2016-03-30 10:21:08 -06:00
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block: hook up writeback throttling
Enable throttling of buffered writeback to make it a lot
more smooth, and has way less impact on other system activity.
Background writeback should be, by definition, background
activity. The fact that we flush huge bundles of it at the time
means that it potentially has heavy impacts on foreground workloads,
which isn't ideal. We can't easily limit the sizes of writes that
we do, since that would impact file system layout in the presence
of delayed allocation. So just throttle back buffered writeback,
unless someone is waiting for it.
The algorithm for when to throttle takes its inspiration in the
CoDel networking scheduling algorithm. Like CoDel, blk-wb monitors
the minimum latencies of requests over a window of time. In that
window of time, if the minimum latency of any request exceeds a
given target, then a scale count is incremented and the queue depth
is shrunk. The next monitoring window is shrunk accordingly. Unlike
CoDel, if we hit a window that exhibits good behavior, then we
simply increment the scale count and re-calculate the limits for that
scale value. This prevents us from oscillating between a
close-to-ideal value and max all the time, instead remaining in the
windows where we get good behavior.
Unlike CoDel, blk-wb allows the scale count to to negative. This
happens if we primarily have writes going on. Unlike positive
scale counts, this doesn't change the size of the monitoring window.
When the heavy writers finish, blk-bw quickly snaps back to it's
stable state of a zero scale count.
The patch registers a sysfs entry, 'wb_lat_usec'. This sets the latency
target to me met. It defaults to 2 msec for non-rotational storage, and
75 msec for rotational storage. Setting this value to '0' disables
blk-wb. Generally, a user would not have to touch this setting.
We don't enable WBT on devices that are managed with CFQ, and have
a non-root block cgroup attached. If we have a proportional share setup
on this particular disk, then the wbt throttling will interfere with
that. We don't have a strong need for wbt for that case, since we will
rely on CFQ doing that for us.
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-09 12:38:14 -07:00
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2016-03-30 10:21:08 -06:00
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2016-04-12 12:32:46 -06:00
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2016-04-13 13:33:19 -06:00
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2016-04-12 12:32:46 -06:00
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2016-04-13 13:33:19 -06:00
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2016-04-12 12:32:46 -06:00
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2016-04-13 13:33:19 -06:00
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2016-04-12 12:32:46 -06:00
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2016-04-13 13:33:19 -06:00
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2016-04-12 12:32:46 -06:00
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block: hook up writeback throttling
Enable throttling of buffered writeback to make it a lot
more smooth, and has way less impact on other system activity.
Background writeback should be, by definition, background
activity. The fact that we flush huge bundles of it at the time
means that it potentially has heavy impacts on foreground workloads,
which isn't ideal. We can't easily limit the sizes of writes that
we do, since that would impact file system layout in the presence
of delayed allocation. So just throttle back buffered writeback,
unless someone is waiting for it.
The algorithm for when to throttle takes its inspiration in the
CoDel networking scheduling algorithm. Like CoDel, blk-wb monitors
the minimum latencies of requests over a window of time. In that
window of time, if the minimum latency of any request exceeds a
given target, then a scale count is incremented and the queue depth
is shrunk. The next monitoring window is shrunk accordingly. Unlike
CoDel, if we hit a window that exhibits good behavior, then we
simply increment the scale count and re-calculate the limits for that
scale value. This prevents us from oscillating between a
close-to-ideal value and max all the time, instead remaining in the
windows where we get good behavior.
Unlike CoDel, blk-wb allows the scale count to to negative. This
happens if we primarily have writes going on. Unlike positive
scale counts, this doesn't change the size of the monitoring window.
When the heavy writers finish, blk-bw quickly snaps back to it's
stable state of a zero scale count.
The patch registers a sysfs entry, 'wb_lat_usec'. This sets the latency
target to me met. It defaults to 2 msec for non-rotational storage, and
75 msec for rotational storage. Setting this value to '0' disables
blk-wb. Generally, a user would not have to touch this setting.
We don't enable WBT on devices that are managed with CFQ, and have
a non-root block cgroup attached. If we have a proportional share setup
on this particular disk, then the wbt throttling will interfere with
that. We don't have a strong need for wbt for that case, since we will
rely on CFQ doing that for us.
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-09 12:38:14 -07:00
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2016-04-12 12:32:46 -06:00
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2008-08-28 09:27:42 +02:00
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2008-01-29 14:53:40 +01:00
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