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349,476 commits

Author SHA1 Message Date
Axel Lin
924a09873c gpio: tegra: Staticize non-exported symbols
Both tegra_gpio_request() and tegra_gpio_free() are not referenced outside of
this file, make them static.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-11-08 22:33:58 +01:00
Brian Foster
00ca79a04b xfs: add minimum file size filtering to eofblocks scan
Support minimum file size filtering in the eofblocks scan. The
caller must set the XFS_EOF_FLAGS_MINFILESIZE flags bit and minimum
file size value in bytes.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-11-08 15:32:29 -06:00
Brian Foster
1b5560488d xfs: support multiple inode id filtering in eofblocks scan
Enhance the eofblocks scan code to filter based on multiply specified
inode id values. When multiple inode id values are specified, only
inodes that match all id values are selected.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-11-08 15:31:13 -06:00
Brian Foster
3e3f9f5863 xfs: add inode id filtering to eofblocks scan
Support inode ID filtering in the eofblocks scan. The caller must
set the associated XFS_EOF_FLAGS_*ID bit and ID field.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-11-08 15:29:14 -06:00
Brian Foster
8ca149de80 xfs: add XFS_IOC_FREE_EOFBLOCKS ioctl
The XFS_IOC_FREE_EOFBLOCKS ioctl allows users to invoke an EOFBLOCKS
scan. The xfs_eofblocks structure is defined to support the command
parameters (scan mode).

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-11-08 15:27:49 -06:00
Brian Foster
41176a68e3 xfs: create function to scan and clear EOFBLOCKS inodes
xfs_inodes_free_eofblocks() implements scanning functionality for
EOFBLOCKS inodes. It uses the AG iterator to walk the tagged inodes
and free post-EOF blocks via the xfs_inode_free_eofblocks() execute
function. The scan can be invoked in best-effort mode or wait
(force) mode.

A best-effort scan (default) handles all inodes that do not have a
dirty cache and we successfully acquire the io lock via trylock. In
wait mode, we continue to cycle through an AG until all inodes are
handled.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-11-08 15:25:40 -06:00
Brian Foster
40165e2761 xfs: make xfs_free_eofblocks() non-static, return EAGAIN on trylock failure
Turn xfs_free_eofblocks() into a non-static function, return EAGAIN to
indicate trylock failure and make sure this error is not propagated in
xfs_release().

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-11-08 15:24:26 -06:00
Laxman Dewangan
8939ddc76a gpio: tegra: fix suspend/resume apis
Following are changes done to fix the suspend/resume
functionality of tegra gpio driver:
- Protect suspend/resume callbacks with CONFIG_PM_SLEEP
  because CONFIG_PM doesn't actually enable any of the PM callbacks, it
  only allows to enable CONFIG_PM_SLEEP and CONFIG_PM_RUNTIME.
  This means if CONFIG_PM is used to protect system sleep callbacks
  then it may end up unreferenced if only runtime PM is enabled.

- Fix the suspend/resume APIs declaration as per callback prototype.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-11-08 22:23:18 +01:00
Brian Foster
72b53efa4a xfs: create helper to check whether to free eofblocks on inode
This check is used in multiple places to determine whether we
should check for (and potentially free) post EOF blocks on an
inode. Add a helper to consolidate the check.

Note that when we remove an inode from the cache (xfs_inactive()),
we are required to trim post-EOF blocks even if the inode is marked
preallocated or append-only to maintain correct space accounting.
The 'force' parameter to xfs_can_free_eofblocks() specifies whether
we should ignore the prealloc/append-only status of the inode.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-11-08 15:22:34 -06:00
Brian Foster
a454f7428f xfs: support a tag-based inode_ag_iterator
Genericize xfs_inode_ag_walk() to support an optional radix tree tag
and args argument for the execute function. Create a new wrapper
called xfs_inode_ag_iterator_tag() that performs a tag based walk
of perag's and inodes.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-11-08 15:20:38 -06:00
Arnaldo Carvalho de Melo
bfaef4b46b perf diff: Use hists__link when not pairing just with baseline
Previously there were blind spots because we were not looking at symbols
that didn't ocurred in the latest run:

  # perf record usleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.018 MB perf.data (~801 samples) ]
  # perf record usleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.018 MB perf.data (~801 samples) ]

Before:

  # perf diff
  # Event 'cycles'
  #
  # Baseline    Delta      Shared Object                         Symbol
  # ........  .......  .................  .............................
  #
              +10.38%  [kernel.kallsyms]  [k] get_empty_filp
               +9.51%  [kernel.kallsyms]  [k] update_sd_lb_stats
               +9.41%  libpopt.so.0.0.0   [.] _init
               +9.29%  [kernel.kallsyms]  [k] vma_interval_tree_insert
       9.05%   +0.12%  [kernel.kallsyms]  [k] do_sys_open
               +9.14%  [kernel.kallsyms]  [k] kfree
               +8.98%  [kernel.kallsyms]  [k] free_pages_and_swap_cache
               +8.78%  [kernel.kallsyms]  [k] unmap_page_range
       9.36%   -0.90%  [kernel.kallsyms]  [k] zap_pte_range
       7.60%   +0.09%  [kernel.kallsyms]  [k] find_next_bit
               +4.37%  [kernel.kallsyms]  [k] place_entity
               +3.38%  [kernel.kallsyms]  [k] __do_page_fault
               +0.80%  [kernel.kallsyms]  [k] native_apic_mem_write
       0.21%   +0.43%  [kernel.kallsyms]  [k] native_write_msr_safe
  #

So 9.05 + 9.36 + 7.60 + 0.21 != 100%

Now using the recently introduced hists__link we can see the whole
picture:

  # perf diff
  # Event 'cycles'
  #
  # Baseline    Delta      Shared Object                         Symbol
  # ........  .......  .................  .............................
  #
       8.44%   -8.44%  [kernel.kallsyms]  [k] _raw_spin_lock
       9.05%   -9.05%  [kernel.kallsyms]  [k] sha_transform
      10.55%  -10.55%  [kernel.kallsyms]  [k] __d_lookup_rcu
              +10.38%  [kernel.kallsyms]  [k] get_empty_filp
      17.70%  -17.70%  [kernel.kallsyms]  [k] kmem_cache_free
               +9.51%  [kernel.kallsyms]  [k] update_sd_lb_stats
               +9.41%  libpopt.so.0.0.0   [.] _init
               +9.29%  [kernel.kallsyms]  [k] vma_interval_tree_insert
       9.05%   +0.12%  [kernel.kallsyms]  [k] do_sys_open
               +9.14%  [kernel.kallsyms]  [k] kfree
               +8.98%  [kernel.kallsyms]  [k] free_pages_and_swap_cache
               +8.78%  [kernel.kallsyms]  [k] unmap_page_range
       9.36%   -0.90%  [kernel.kallsyms]  [k] zap_pte_range
       7.60%   +0.09%  [kernel.kallsyms]  [k] find_next_bit
               +4.37%  [kernel.kallsyms]  [k] place_entity
               +3.38%  [kernel.kallsyms]  [k] __do_page_fault
       4.01%   -4.01%  [kernel.kallsyms]  [k] handle_pte_fault
       9.27%   -9.27%  [kernel.kallsyms]  [k] find_get_page
       0.78%   -0.78%  [kernel.kallsyms]  [k] rcu_irq_enter
       0.57%   -0.57%  [kernel.kallsyms]  [k] finish_task_switch
       4.25%   -4.25%  [kernel.kallsyms]  [k] run_timer_softirq
               +0.80%  [kernel.kallsyms]  [k] native_apic_mem_write
       0.21%   +0.43%  [kernel.kallsyms]  [k] native_write_msr_safe
       9.16%   -9.16%  ld-2.12.so         [.] close
  #

Now:

8.44 + 9.05 + 10.55 + 17.70 + 9.05 + 9.36 +
7.60 + 4.01 + 9.27 + 0.78 + 0.57 + 4.25 + 0.21 + 9.16 == 100%

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-jeq55qdgby1745bs8r9sscdh@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-11-08 18:08:26 -03:00
Arnaldo Carvalho de Melo
494d70a181 perf hists: Introduce hists__link
That given two hists will find the hist_entries (buckets) in the second
hists that are for the same bucket in the first and link them, then it
will look for all buckets in the second that don't have a counterpart in
the first and will create a dummy counterpart that will then be linked
to the entry in the second.

For multiple events this will be done pairing the leader with all the
other events in the group, so that in the end the leader will have all
the buckets in all the hists in a group, dummy or not while the other
hists will be left untouched.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-l9l9ieozqdhn9lieokd95okw@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-11-08 18:08:15 -03:00
Arnaldo Carvalho de Melo
95529be478 perf diff: Move hists__match to the hists lib
Its not 'diff' specific and will be useful for other use cases, like
bucketizing multiple events in a single session.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-o35urjgxfxxm70aw1wa81s4w@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-11-08 17:57:37 -03:00
Arnaldo Carvalho de Melo
b821c73253 perf diff: Start moving to support matching more than two hists
We want to match more than two hists, so that we can match more than two
perf.data files and moreover, match hist_entries (buckets) in multiple
events in a group.

So the "baseline"/"leader" will instead of a ->pair pointer, use a
list_head, that will link to the pairs and hists__match use it.

Following that perf_evlist__link will link the hists in its evsel
groups.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-2kbmzepoi544ygj9godseqpv@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-11-08 17:43:09 -03:00
Namhyung Kim
ff6f7778a6 perf tools: Don't try to lookup objdump for live mode
Arnaldo reported that annotation during perf top resulted in a segfault.
It was because the env->arch was NULL and we don't set it for a live
session.  In fact, no need to look up objdump in this case since we can
use system's default (native) objdump.

Reported-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Irina Tirdea <irina.tirdea@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1352251815-12615-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-11-08 17:26:52 -03:00
Brian Foster
27b5286792 xfs: add EOFBLOCKS inode tagging/untagging
Add the XFS_ICI_EOFBLOCKS_TAG inode tag to identify inodes with
speculatively preallocated blocks beyond EOF. An inode is tagged
when speculative preallocation occurs and untagged either via
truncate down or when post-EOF blocks are freed via release or
reclaim.

The tag management is intentionally not aggressive to prefer
simplicity over the complexity of handling all the corner cases
under which post-EOF blocks could be freed (i.e., forward
truncation, fallocate, write error conditions, etc.). This means
that a tagged inode may or may not have post-EOF blocks after a
period of time. The tag is eventually cleared when the inode is
released or reclaimed.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-11-08 14:20:44 -06:00
Zheng Liu
c0677e6d0f ext4: add data structures for the extent status tree
This patch adds two structures that supports extent status tree, extent_status
and ext4_es_tree.  Currently extent_status is used to track a delay extent for
an inode, which record the start block and the length of the delay extent.
ext4_es_tree is used to store all extent_status for an inode in memory.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: Allison Henderson <achender@linux.vnet.ibm.com>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-11-08 15:18:54 -05:00
Lukas Czerner
07aa2ea138 ext4: fix error handling in ext4_fill_super()
There are some places in ext4_fill_super() where we would not return
proper error code if something fails. The confusion is caused probably
due to the fact that we have two "kind-of" return variables 'ret'and
'err'.

'ret' is used to return error code from ext4_fill_super() where err is
used to store return values from other functions within ext4_fill_super().
However some places were missing the obligatory 'ret = err'. We could
put the assignment where it is missing, but we can have better "future
proof" solution. Or we could convert the code to use just one, but it
would require more rewrites.

This commit fixes the problem by returning value from 'err' variable if
it is set and 'ret' otherwise in error handling branch of the
ext4_fill_super(). The reasoning is that 'ret' value is often set to
default "-EINVAL" or explicit value, where 'err' is used to store
return value from other functions and should be otherwise zero.

https://bugzilla.kernel.org/show_bug.cgi?id=48431

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-11-08 15:16:54 -05:00
Eugene Shatokhin
24ec19b0ae ext4: fix memory leak in ext4_xattr_set_acl()'s error path
In ext4_xattr_set_acl(), if ext4_journal_start() returns an error,
posix_acl_release() will not be called for 'acl' which may result in a
memory leak.

This patch fixes that.

Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Eugene Shatokhin <eugene.shatokhin@rosalab.ru>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
2012-11-08 15:11:11 -05:00
Anatol Pomozov
8b0f165f79 ext4: remove code duplication in ext4_get_block_write_nolock()
729f52c6be introduced function ext4_get_block_write_nolock() that
is very similar to _ext4_get_block(). Eliminate code duplication
by passing different flags to _ext4_get_block()

Tested: xfs tests

Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-11-08 15:07:16 -05:00
Paul E. McKenney
7bd8f2a74b rcu: Add tracing for synchronize_sched_expedited()
This commit adds a per-RCU-flavor "rcuexp" file that dumps out
statistics for synchonize_sched_expedited().

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-08 11:57:07 -08:00
Michael Wang
6ee0886ff6 rcu: Remove old debugfs interfaces and also RCU flavor name
This commit removes the old debugfs interfaces, so that the new
directory-per-RCU-flavor versions remain.  Because the RCU flavor is
given by the directory name, there is no need to print it out, so remove
the name from the printout.

Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-08 11:56:44 -08:00
Michael Wang
a608d84bdb rcu: split 'rcuhier' to each flavor
This patch add new 'rcuhier' to each flavor's folder, now we could use:
	'cat /debugfs/rcu/rsp/rcuhier'
to get the selected rsp info.

Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-08 11:55:45 -08:00
Michael Wang
66b38bc52b rcu: split 'rcugp' to each flavor
This patch add new 'rcugp' to each flavor's folder, now we could use:
	'cat /debugfs/rcu/rsp/rcugp'
to get the selected rsp info.

Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-08 11:55:44 -08:00
Michael Wang
29c67764f1 rcu: split 'rcuboost' to each flavor
This patch add new 'rcuboost' to each flavor's folder, now we could use:
	'cat /debugfs/rcu/rsp/rcuboost'
to get the selected rsp info.

Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-08 11:55:42 -08:00
Michael Wang
c25e557f5d rcu: split 'rcubarrier' to each flavor
This patch add new 'rcubarrier' to each flavor's folder, now we could use:
	'cat /debugfs/rcu/rsp/rcubarrier'
to get the selected rsp info.

Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-08 11:55:41 -08:00
Paul E. McKenney
42c3533eee rcu: Fix tracing formatting
The rcu_state structure's ->completed field is unsigned long, so this
commit adjusts show_one_rcugp()'s printf() format to suit.  Also add
the required ACCESS_ONCE() directives while we are in this function.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-08 11:55:30 -08:00
Anatol Pomozov
8d8c182570 ext4: use 'inode' variable that is already dereferenced
Tested: xfs tests

Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-11-08 14:53:35 -05:00
Trond Myklebust
642fe4d00d SUNRPC: Fix validity issues with rpc_pipefs sb->s_fs_info
rpc_kill_sb() must defer calling put_net() until after the notifier
has been called, since most (all?) of the notifier callbacks assume
that sb->s_fs_info points to a valid net namespace. It also must not
call put_net() if the call to rpc_fill_super was unsuccessful.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=48421

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Stanislav Kinsbursky <skinsbursky@parallels.com>
Cc: stable@vger.kernel.org [>= v3.4]
2012-11-08 14:53:28 -05:00
Michael Wang
5f4ee1fa16 rcu: Remove the interface "rcudata.csv"
This patch removes the interface "rcudata.csv" since it is apparently
not used.

Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-08 11:50:19 -08:00
Michael Wang
c011c41f11 rcu: Replace the old interface with the new one
This patch removed the old RCU debugfs interface and replaced it with
the new one.

Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-08 11:50:18 -08:00
Michael Wang
51d0f16d49 rcu: Optimize the 'rcu_pending' for RCU trace
This patch implements the new 'rcu_pending' interface under each rsp
directory, by using the 'CPU units sequence reading', thus avoiding loss
of tracing data.

Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-08 11:50:17 -08:00
Michael Wang
d29200efa2 rcu: Optimize the 'rcudata.csv' for RCU trace
This patch implements the new 'rcudata.csv' interface under each rsp
directory, by using the 'CPU units sequence reading', thus avoiding loss
of tracing data.

Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-08 11:50:16 -08:00
Michael Wang
878eda72e2 rcu: Optimize the 'rcudata' for RCU trace
This patch implements the new 'rcudata' interface under each rsp
directory, by using the 'CPU units sequence reading', thus avoiding loss
of tracing data.

Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-08 11:50:16 -08:00
Michael Wang
374b928ee8 rcu: Fundamental facility for 'CPU units sequence reading'
This patch add the fundamental facility used by the following patches, so we
can implement the 'CPU units sequence reading' later.

This helps us avoid losing data when there are too many CPUs and too
small of a buffer, since this new approach allows userspace to read out
the data one CPU at a time.  Thus, if the buffer is not large enough,
userspace will get whatever CPUs fit, and can then issue another read
for the remainder of the data.

Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-08 11:50:15 -08:00
Michael Wang
573bcd40d2 rcu: Create directory for each flavor of rcu
This patch will create subdirectory according to each flavor of rcu, the new
structure will be:

	/debugfs/rcu/ -> rsp_0
		      -> rsp_1
		      -> ...

So we can go to '/debugfs/rcu/rsp_0' and get the cpu info of rsp_0 there.
The flavors of RCU are currently rcu_bh, rcu_preempt, and rcu_sched.

Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-08 11:50:14 -08:00
Paul E. McKenney
a30489c522 rcu: Instrument synchronize_rcu_expedited() for debugfs tracing
This commit adds the counters to rcu_state and updates them in
synchronize_rcu_expedited() to provide the data needed for debugfs
tracing.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-08 11:50:13 -08:00
Paul E. McKenney
40694d6644 rcu: Move synchronize_sched_expedited() state to rcu_state
Tracing (debugfs) of expedited RCU primitives is required, which in turn
requires that the relevant data be located where the tracing code can find
it, not in its current static global variables in kernel/rcutree.c.
This commit therefore moves sync_sched_expedited_started and
sync_sched_expedited_done to the rcu_state structure, as fields
->expedited_start and ->expedited_done, respectively.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-08 11:50:12 -08:00
Paul E. McKenney
1924bcb025 rcu: Avoid counter wrap in synchronize_sched_expedited()
There is a counter scheme similar to ticket locking that
synchronize_sched_expedited() uses to service multiple concurrent
callers with the same expedited grace period.  Upon entry, a
sync_sched_expedited_started variable is atomically incremented,
and upon completion of a expedited grace period a separate
sync_sched_expedited_done variable is atomically incremented.

However, if a synchronize_sched_expedited() is delayed while
in try_stop_cpus(), concurrent invocations will increment the
sync_sched_expedited_started counter, which will eventually overflow.
If the original synchronize_sched_expedited() resumes execution just
as the counter overflows, a concurrent invocation could incorrectly
conclude that an expedited grace period elapsed in zero time, which
would be bad.  One could rely on counter size to prevent this from
happening in practice, but the goal is to formally validate this
code, so it needs to be fixed anyway.

This commit therefore checks the gap between the two counters before
incrementing sync_sched_expedited_started, and if the gap is too
large, does a normal grace period instead.  Overflow is thus only
possible if there are more than about 3.5 billion threads on 32-bit
systems, which can be excluded until such time as task_struct fits
into a single byte and 4G/4G patches are accepted into mainline.
It is also easy to encode this limitation into mechanical theorem
provers.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-08 11:50:12 -08:00
Paul E. McKenney
7b2e6011f1 rcu: Rename ->onofflock to ->orphan_lock
The ->onofflock field in the rcu_state structure at one time synchronized
CPU-hotplug operations for RCU.  However, its scope has decreased over time
so that it now only protects the lists of orphaned RCU callbacks.  This
commit therefore renames it to ->orphan_lock to reflect its current use.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-08 11:50:11 -08:00
Zheng Liu
3779473246 ext4: fix missing call to trace_ext4_ext_map_blocks_exit
When ext4_ext_handle_uninitialized_extents(), we will directly return
from ext4_ext_map_blocks().  The trace point of
trace_ext4_ext_map_blocks_exit isn't called, and the user doesn't see
any result.  This patch tries to fix this problem.

Meanwhile in ext4_ext_handle_uninitialized_extents it returns errors
or the number of allocated blocks.  So 'ret' variable can be removed
due to previously modifications.

Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
2012-11-08 14:47:52 -05:00
Paul E. McKenney
a4d611fdca rcu: Document alternative RCU/reference-count algorithms
The approach for mixing RCU and reference counting listed in the RCU
documentation only describes one possible approach.  This approach can
result in failure on the read side, which is nice if you want fresh data,
but not so good if you want simple code.  This commit therefore adds
two additional approaches that feature unconditional reference-count
acquisition by RCU readers.  These approaches are very similar to that
used in the security code.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-08 11:44:38 -08:00
Kees Cook
57d34a6cee rcu: Update docs to include kfree_rcu()
Mention kfree_rcu() in the call_rcu() section.  Additionally fix the
example code for list replacement that used the wrong structure element.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-08 11:44:25 -08:00
Zheng Liu
19b303d8b5 ext4: print map->m_flags in trace_ext4_ext/ind_map_blocks_exit
When we use trace_ext4_ext/ind_map_blocks_exit, print the value of
map->m_flags in order that we can understand the extent's current
status.

Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-11-08 14:34:04 -05:00
Zheng Liu
b5645534ce ext4: print 'flags' in ext4_ext_handle_uninitialized_extents
In trace_ext4_ext_handle_uninitialized_extents we don't care about the
value of map->m_flags because this value is probably 0, and we prefer
to get the value of flags because we can know how to handle this
extent in this function.

Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-11-08 14:33:43 -05:00
Paul Walmsley
c4ceedcb18 ARM: OMAP2+: CM/clock: convert _omap2_module_wait_ready() to use SoC-independent CM functions
Convert the OMAP clock code's _omap2_module_wait_ready() to use
SoC-independent CM functions that are provided by the CM code, rather
than using a deprecated function from mach-omap2/prcm.c.

This facilitates the future conversion of the CM code to a driver, and
also removes a mach-omap2/prcm.c user.  mach-omap2/prcm.c will be removed
by a subsequent patch.

Some modules have IDLEST registers that aren't in the CM module, such
as the AM3517 IDLEST bits.  So we also need a fallback function for
these non-CM odd cases.  Create a temporary one in mach-omap2/clock.c,
intended to exist until the SCM drivers are ready.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Tested-by: Vaibhav Hiremath <hvaibhav@ti.com>
2012-11-08 12:33:08 -07:00
Paul Walmsley
b6ffa05091 ARM: OMAP2xxx: APLL/CM: convert to use omap2_cm_wait_module_ready()
Convert the OMAP2xxx APLL code to use omap2_cm_wait_module_ready(),
and move the low-level CM register manipulation functions to
mach-omap2/cm2xxx.c.  The objectives here are to remove the dependency
on the deprecated omap2_cm_wait_idlest() function in
mach-omap2/prcm.c, so that code can be removed later; and move
low-level register accesses to the CM IP block to the CM code, which
will soon be moved into drivers/.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Tested-by: Vaibhav Hiremath <hvaibhav@ti.com>
2012-11-08 12:33:08 -07:00
Paul Walmsley
187e3e06e8 ARM: OMAP2+: board files: use SoC-specific system restart functions
Modify the board files to use the SoC-specific system restart
functions.  At this point it's possible to remove omap_prcm_restart()
from mach-omap2/prcm.c.

While removing the prototypes for the now-unused restart functions, clean
up a few more obsolete prototypes in mach-omap2/clock.h.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Tested-by: Vaibhav Hiremath <hvaibhav@ti.com>
2012-11-08 12:33:08 -07:00
Paul Walmsley
2f334a3896 ARM: OMAP2+: PRCM: create SoC-specific chip restart functions
Split omap_prcm_restart() from mach-omap2/prcm.c into SoC-specific
variants.  These functions need to be able to save the reboot reason
into the scratchpad RAM.  This implies a dependency on both the PRM
and SCM IP blocks, so they've been moved into their own file.  This
will eventually call functions in the PRM and SCM drivers, once those
are created.

Vaibhav Hiremath <hvaibhav@ti.com> identified an unused prototype in
the first version of this patch - now removed.  Tony Lindgren
<tony@atomide.com> noted a compile problem with some RMK Kconfigs;
resolved in this patch.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Vaibhav Hiremath <hvaibhav@ti.com>
Tested-by: Vaibhav Hiremath <hvaibhav@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
2012-11-08 12:33:08 -07:00
Paul Walmsley
baa689b8b2 ARM: OMAP2xxx: clock: move virt_prcm_set code into clkt2xxx_virt_prcm_set.c
Collect all of the virt_prcm_set-specific clocktype code into
mach-omap2/clkt2xxx_virt_prcm_set.c.  Remove its dependency on the
'sclk' and 'vclk' global variables.  Those variables will be removed
by subsequent patches.

This is part of the process of cleaning up the OMAP2xxx clock code
and preparing for the removal of the omap_prcm_restart() function.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Tested-by: Vaibhav Hiremath <hvaibhav@ti.com>
2012-11-08 12:33:08 -07:00