Commit Graph

408276 Commits

Author SHA1 Message Date
Sangjung Woo
1fbc4c4d79 drivers/rtc/rtc-puv3.c: use dev_dbg() instead of pr_debug()
Because dev_*() are used along with pr_debug() function in this code, the
debug message is not tidy.  This patch converts from pr_debug() to
dev_dbg() since dev_*() are encouraged to use in device driver code.

Signed-off-by: Sangjung Woo <sangjung.woo@samsung.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:31 +09:00
Michal Simek
a272606192 drivers/rtc/rtc-pl03x.c: remove unnecessary amba_set_drvdata()
Driver core clears the driver data to NULL after device_release or on
probe failure, so just remove it from here.

The relevant driver core change was commit 0998d06310 ("device-core:
Ensure drvdata = NULL when no driver is bound").

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:31 +09:00
Peter Senna Tschudin
c8b18da776 drivers/rtc/rtc-ds1307.c: change variable type to bool
The variable want_irq is only assigned the values true and false.
Change its type to bool.

The simplified semantic patch that find this problem is as
follows (http://coccinelle.lip6.fr/):

@exists@
type T;
identifier b;
@@
- T
+ bool
  b = ...;
  ... when any
  b = \(true\|false\)

Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:30 +09:00
Sachin Kamat
462a465be2 drivers/rtc/rtc-stmp3xxx.c: remove redundant of_match_ptr
The data structure of_match_ptr() protects is always compiled in.
Hence of_match_ptr() is not needed.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:30 +09:00
Sachin Kamat
c39b3717b8 drivers/rtc/rtc-snvs.c: remove redundant of_match_ptr
The data structure of_match_ptr() protects is always compiled in.
Hence of_match_ptr() is not needed.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:30 +09:00
Sachin Kamat
d149632e03 drivers/rtc/rtc-sirfsoc.c: remove redundant of_match_ptr
The data structure of_match_ptr() protects is always compiled in.
Hence of_match_ptr() is not needed.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:30 +09:00
Sachin Kamat
616b734130 drivers/rtc/rtc-omap.c: remove redundant of_match_ptr
The data structure of_match_ptr() protects is always compiled in.
Hence of_match_ptr() is not needed.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:30 +09:00
Sachin Kamat
ce6bafdf94 drivers/rtc/rtc-vt8500.c: remove redundant of_match_ptr
The data structure of_match_ptr() protects is always compiled in.
Hence of_match_ptr() is not needed.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Tony Prisk <linux@prisktech.co.nz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:30 +09:00
Jingoo Han
a65ddcebab drivers/rtc/rtc-v3020.c: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.  This is a cosmetic change to make
the code simpler and enhance the readability.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:30 +09:00
Jingoo Han
e58c18d434 drivers/rtc/rtc-sh.c: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.  This is a cosmetic change to make
the code simpler and enhance the readability.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:30 +09:00
Jingoo Han
f6405afe23 drivers/rtc/rtc-rs5c348.c: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.  This is a cosmetic change to make
the code simpler and enhance the readability.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:29 +09:00
Jingoo Han
ffc75bb8f2 drivers/rtc/rtc-pcf2123.c: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.  This is a cosmetic change to make
the code simpler and enhance the readability.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:29 +09:00
Jingoo Han
b5f0902dcd drivers/rtc/rtc-m48t86.c: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.  This is a cosmetic change to make
the code simpler and enhance the readability.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:29 +09:00
Jingoo Han
8136032ba5 drivers/rtc/rtc-m48t59.c: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.  This is a cosmetic change to make
the code simpler and enhance the readability.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:29 +09:00
Jingoo Han
28dc5f8038 drivers/rtc/rtc-ep93xx.c: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.  This is a cosmetic change to make
the code simpler and enhance the readability.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:29 +09:00
Jingoo Han
77bf38223c drivers/rtc/rtc-ds2404.c: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.  This is a cosmetic change to make
the code simpler and enhance the readability.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:29 +09:00
Jingoo Han
01ce893d37 drivers/rtc/rtc-ds1307.c: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.  This is a cosmetic change to make
the code simpler and enhance the readability.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:29 +09:00
Jingoo Han
cfa13b249e drivers/rtc/rtc-ds1305.c: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.  This is a cosmetic change to make
the code simpler and enhance the readability.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:28 +09:00
Jingoo Han
d1fa245248 drivers/rtc/rtc-da9055.c: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.  This is a cosmetic change to make
the code simpler and enhance the readability.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:28 +09:00
Jingoo Han
97a92e77ca drivers/rtc/rtc-cmos.c: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.  This is a cosmetic change to make
the code simpler and enhance the readability.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:28 +09:00
Jingoo Han
82df0b2855 drivers/rtc/rtc-88pm860x.c: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.  This is a cosmetic change to make
the code simpler and enhance the readability.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Haojian Zhuang <haojian.zhuang@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:28 +09:00
Jingoo Han
b5ebf0780d drivers/rtc/rtc-88pm80x.c: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.  This is a cosmetic change to make
the code simpler and enhance the readability.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:28 +09:00
Jingoo Han
b7efdf3b1b drivers/rtc/rtc-sirfsoc.c: remove unneeded casts of void*
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:28 +09:00
Sachin Kamat
4271e7ff1a drivers/rtc/rtc-vr41xx.c: fix checkpatch warnings
Fixes the following warnings:
  WARNING: Use #include <linux/io.h> instead of <asm/io.h>
  WARNING: Use #include <linux/uaccess.h> instead of <asm/uaccess.h>

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Yoichi Yuasa <yuasa@linux-mips.org>
Cc: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:28 +09:00
Sachin Kamat
8e3dd0d8e9 drivers/rtc/rtc-mrst.c: remove redundant dev_set_drvdata
Driver core sets the driver data to NULL upon device_release or on probe
failure.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:27 +09:00
Sachin Kamat
d7d954acb7 drivers/rtc/rtc-cmos.c: remove redundant dev_set_drvdata
Driver core sets the driver data to NULL upon device_release or on probe
failure.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:27 +09:00
Sachin Kamat
3d09162e99 drivers/rtc/rtc-sirfsoc.c: use devm_rtc_device_register
devm_rtc_device_register simplifies the code.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Xianglong Du <Xianglong.Du@csr.com>
Cc: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:27 +09:00
Sachin Kamat
adce8c14c9 drivers/rtc/rtc-isl1208.c: use devm_* APIs
devm_* APIs are device managed and make code simpler.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Herbert Valerio Riedel <hvr@gnu.org>
Cc: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:27 +09:00
Sachin Kamat
f3766250b2 drivers/rtc/rtc-at91rm9200.c: use devm_* APIs
devm_* APIs are device managed and make code simpler.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:27 +09:00
Sachin Kamat
58f27d7d06 drivers/rtc/rtc-vt8500.c: fix return value
Propagate the return value from platform_get_irq() instead of hardcoding.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:27 +09:00
Sachin Kamat
f16189aca0 drivers/rtc/rtc-max6900.c: remove redundant checks
i2c_smbus_write_byte_data() returns negative errno on failure or 0 on
success.  Return the value obtained from it directly.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:27 +09:00
Sachin Kamat
c91fd91d68 drivers/rtc/rtc-isl1208.c: remove redundant checks
i2c_smbus_read_byte_data() returns negative errno on failure.  Return the
value obtained from it directly.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Herbert Valerio Riedel <hvr@gnu.org>
Cc: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:27 +09:00
Sachin Kamat
50ccf0455e drivers/rtc/rtc-ds1307.c: release irq on error
'client->irq' was not released on error. Fix it.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:26 +09:00
Wei Yongjun
10992435b3 drivers/message/i2o/driver.c: add missing destroy_workqueue() on error in i2o_driver_register()
Add the missing destroy_workqueue() before return from
i2o_driver_register() in the error handling case.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:26 +09:00
Joe Mario
ab76786561 kprobes: use KSYM_NAME_LEN to size identifier buffers
Use KSYM_NAME_LEN to size identifier buffers, so that it can be easier
increased.

Signed-off-by: Joe Mario <jmario@redhat.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:26 +09:00
P J P
9ba4bcb645 initramfs: read CONFIG_RD_ variables for initramfs compression
When expert configuration option(CONFIG_EXPERT) is enabled, menuconfig
offers a choice of compression algorithm to compress initial ramfs image;
This choice is stored into CONFIG_RD_* variables.  But usr/Makefile uses
earlier INITRAMFS_COMPRESSION_* macros to build initial ramfs file.  Since
none of them is defined, resulting 'initramfs_data.cpio' file remains
un-compressed.

This patch updates the Makefile to use CONFIG_RD_* variables and adds
support for LZ4 compression algorithm.  Also updates the
'gen_initramfs_list.sh' script to check whether a selected compression
command is accessible or not.  And fall-back to default gzip(1)
compression when it is not.

Signed-off-by: P J P <prasad@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:26 +09:00
Michael Opdenacker
ba24762bd5 init: make init failures more explicit
This patch proposes to make init failures more explicit.

Before this, the "No init found" message didn't help much.  It could
sometimes be misleading and actually mean "No *working* init found".

This message could hide many different issues:
 - no init program candidates found at all
 - some init program candidates exist but can't be executed (missing
   execute permissions, failed to load shared libraries, executable
   compiled for an unknown architecture...)

This patch notifies the kernel user when a candidate init program is found
but can't be executed.  In each failure situation, the error code is
displayed, to quickly find the root cause.  "No init found" is also
replaced by "No working init found", which is more correct.

This will help embedded Linux developers (especially the newcomers),
regularly making and debugging new root filesystems.

Credits to Geert Uytterhoeven and Janne Karhunen for their improvement
suggestions.

Signed-off-by: Michael Opdenacker <michael.opdenacker@free-electrons.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Janne Karhunen <Janne.Karhunen@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:26 +09:00
P J P
df3ef3af50 init/do_mounts_rd.c: fix NULL pointer dereference while loading initramfs
Make menuconfig allows one to choose compression format of an initial
ramdisk image.  But this choice does not result in duly compressed initial
ramdisk image.  Because - $ make install - does not pass on the selected
compression choice to the dracut(8) tool, which creates the initramfs
file.  dracut(8) generates the image with the default compression, ie.
gzip(1).

If a user chose any other compression instead of gzip(1), it leads to a
crash due to NULL pointer dereference in crd_load(), caused by a NULL
function pointer returned by the 'decompress_method()' routine.  Because
the initramfs image is gzip(1) compressed, whereas the kernel knows only
to decompress the chosen format and not gzip(1).

This patch replaces the crash by an explicit panic() call with an
appropriate error message. This shall prevent the kernel from
eventually panicking in: init/do_mounts.c: mount_block_root() with
  -> panic("VFS: Unable to mount root fs on %s", b);

[akpm@linux-foundation.org: mention that the problem is with the ramdisk, don't print known-to-be-NULL value]
Signed-off-by: P J P <prasad@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:26 +09:00
Geert Uytterhoeven
65321547c8 init.h: document the existence of __initconst
Initdata can be const since more than 5 years, using the __initconst
keyword.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:26 +09:00
Jason Baron
67347fe4e6 epoll: do not take global 'epmutex' for simple topologies
When calling EPOLL_CTL_ADD for an epoll file descriptor that is attached
directly to a wakeup source, we do not need to take the global 'epmutex',
unless the epoll file descriptor is nested.  The purpose of taking the
'epmutex' on add is to prevent complex topologies such as loops and deep
wakeup paths from forming in parallel through multiple EPOLL_CTL_ADD
operations.  However, for the simple case of an epoll file descriptor
attached directly to a wakeup source (with no nesting), we do not need to
hold the 'epmutex'.

This patch along with 'epoll: optimize EPOLL_CTL_DEL using rcu' improves
scalability on larger systems.  Quoting Nathan Zimmer's mail on SPECjbb
performance:

"On the 16 socket run the performance went from 35k jOPS to 125k jOPS.  In
addition the benchmark when from scaling well on 10 sockets to scaling
well on just over 40 sockets.

...

Currently the benchmark stops scaling at around 40-44 sockets but it seems like
I found a second unrelated bottleneck."

[akpm@linux-foundation.org: use `bool' for boolean variables, remove unneeded/undesirable cast of void*, add missed ep_scan_ready_list() kerneldoc]
Signed-off-by: Jason Baron <jbaron@akamai.com>
Tested-by: Nathan Zimmer <nzimmer@sgi.com>
Cc: Eric Wong <normalperson@yhbt.net>
Cc: Nelson Elhage <nelhage@nelhage.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Davide Libenzi <davidel@xmailserver.org>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:25 +09:00
Jason Baron
ae10b2b4eb epoll: optimize EPOLL_CTL_DEL using rcu
Nathan Zimmer found that once we get over 10+ cpus, the scalability of
SPECjbb falls over due to the contention on the global 'epmutex', which is
taken in on EPOLL_CTL_ADD and EPOLL_CTL_DEL operations.

Patch #1 removes the 'epmutex' lock completely from the EPOLL_CTL_DEL path
by using rcu to guard against any concurrent traversals.

Patch #2 remove the 'epmutex' lock from EPOLL_CTL_ADD operations for
simple topologies.  IE when adding a link from an epoll file descriptor to
a wakeup source, where the epoll file descriptor is not nested.

This patch (of 2):

Optimize EPOLL_CTL_DEL such that it does not require the 'epmutex' by
converting the file->f_ep_links list into an rcu one.  In this way, we can
traverse the epoll network on the add path in parallel with deletes.
Since deletes can't create loops or worse wakeup paths, this is safe.

This patch in combination with the patch "epoll: Do not take global 'epmutex'
for simple topologies", shows a dramatic performance improvement in
scalability for SPECjbb.

Signed-off-by: Jason Baron <jbaron@akamai.com>
Tested-by: Nathan Zimmer <nzimmer@sgi.com>
Cc: Eric Wong <normalperson@yhbt.net>
Cc: Nelson Elhage <nelhage@nelhage.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Davide Libenzi <davidel@xmailserver.org>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
CC: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:25 +09:00
Joe Perches
823b794ce1 checkpatch: add check for sscanf without return use
Naked use sscanf can be troublesome because the pointed to variables may
not have been set.

Add a warning when the sscanf return value is not used.

For now, do not add __must_check to the sscanf prototype because that will
cause a couple of hundred new warnings when compiling a kernel.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:25 +09:00
Joe Perches
2b7ab45395 checkpatch: don't require kernel style __attribute__ shortcuts in uapi paths
Avoid prescribing kernel styled shortcuts for gcc extensions of
__attribute__((foo)) in the uapi include paths.

Fix $realfile filename when using -f/--file to not remove first level
directory as if the filename was used in a -P1 patch.  Only strip the
first level directory (typically a or b) for P1 patches.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: "Dixit, Ashutosh" <ashutosh.dixit@intel.com>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:25 +09:00
Joe Perches
507e51418c checkpatch: improve "return is not a function" test
Find a few more cases where parentheses are used around the value of a
return statement.

This now uses the "$balanced_parens" test and also makes the test depend
on perl v5.10 and higher.

This now finds return with parenthesis uses the old code did not find
like:

ERROR: return is not a function, parentheses are not required
#211: FILE: arch/m68k/include/asm/sun3xflop.h:211:
+		return ((error == 0) ? 0 : -1);

Signed-off-by: Joe Perches <joe@perches.com>
Tested-by: David Cohen <david.a.cohen@linux.intel.com>
Acked-by: David Cohen <david.a.cohen@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:25 +09:00
Josh Triplett
4783f894d0 checkpatch.pl: check for the FSF mailing address
Kernel maintainers reject new instances of the GPL boilerplate paragraph
directing people to write to the FSF for a copy of the GPL, since the FSF
has moved in the past and may do so again.

Make this an error for new code, but just a --strict CHK in --file mode;
anyone interested in doing tree-wide cleanups of this form can enable this
test explicitly.

Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:25 +09:00
Joe Perches
c1fd7bb996 checkpatch: make the memory barrier test noisier
Peter Zijlstra prefers that comments be required near uses of memory
barriers.

Change the message level for memory barrier uses from a --strict test only
to a normal WARN so it's always emitted.

This might produce false positives around insertions of memory barriers
when a comment is outside the patch context block.

And checkpatch is still stupid, it only looks for existence of any
comment, not at the comment content.

Signed-off-by: Joe Perches <joe@perches.com>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:25 +09:00
Joe Perches
e970b8846a checkpatch: add rules to check init attribute and const defects
People get this regularly wrong and it breaks the LTO builds, as it causes
a section attribute conflict.

Add --fix capability too.

Based on a patch from Andi Kleen.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:25 +09:00
Joe Perches
52ea85061d checkpatch: add test for #defines of ARCH_HAS_<foo>
Add a test for these #defines

Additionally, moved string_find_replace sub as it screws up subsequent
formatting when placed inside another sub.

Signed-off-by: Joe Perches <joe@perches.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:24 +09:00
Joe Perches
11ea516a6c checkpatch: find CamelCase definitions of struct/union/enum
Checkpatch doesn't currently find CamelCase definitions of structs, unions
or enums.

Add that ability.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:24 +09:00
Joe Perches
066687279c checkpatch: update seq_<foo> tests
seq_vprintf, seq_printf and seq_puts are logging functions and should be
allowed to exceed the maximium line length.

Add maximum line length exceptions for these functions.

Also, suggesting seq_printf conversions to seq_puts should be tested for
arguments after the format.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:24 +09:00