Commit Graph

40 Commits

Author SHA1 Message Date
Jim Cromie
85f7f6c0ed dynamic_debug: process multiple debug-queries on a line
Insert ddebug_exec_queries() in place of ddebug_exec_query().  It
splits the query string on [;\n], and calls ddebug_exec_query() on
each.  All queries are processed independent of errors, allowing a
query to fail, for example when a module is not installed.  Empty
lines and comments are skipped.  Errors are counted, and the last
error seen (negative) or the number of callsites found (0 or positive)
is returned.  Return code checks are altered accordingly.

With this, multiple queries can be given in ddebug_query, allowing
more selective enabling of callsites.  As a side effect, a set of
commands can be batched in:

	cat cmd-file > $DBGMT/dynamic_debug/control

We dont want a ddebug_query syntax error to kill the dynamic debug
facility, so dynamic_debug_init() zeros ddebug_exec_queries()'s return
code after logging the appropriate message, so that ddebug tables are
preserved and $DBGMT/dynamic_debug/control file is created.  This
would be appropriate even without accepting multiple queries.

This patch also alters ddebug_change() to return number of callsites
matched (which typically is the same as number of callsites changed).
ddebug_exec_query() also returns the number found, or a negative value
if theres a parse error on the query.

Splitting on [;\n] prevents their use in format-specs, but selecting
callsites on punctuation is brittle anyway, meaningful and selective
substrings are more typical.

Note: splitting queries on ';' before handling trailing #comments
means that a ';' also terminates a comment, and text after the ';' is
treated as another query.  This trailing query will almost certainly
result in a parse error and thus have no effect other than the error
message.  The double corner case with unexpected results is:

     ddebug_query="func foo +p # enable foo ; +p"

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-24 12:50:36 -08:00
Jim Cromie
574b3725e3 dynamic_debug: factor vpr_info_dq out of ddebug_parse_query
Factor pr_info(query) out of ddebug_parse_query, into vpr_info_dq(),
for reuse later.  Also change the printed labels: file, func to agree
with the query-spec keywords accepted in the control file.  Pass ""
when string is null, to avoid "(null)" output from sprintf.  For
format print, use precision to skip last char, assuming its '\n', no
great harm if not, its a debug msg.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-24 12:50:36 -08:00
Jim Cromie
2b6783191d dynamic_debug: add trim_prefix() to provide source-root relative paths
trim_prefix(path) skips past the absolute source path root, and
returns the pointer to the relative path from there.  It is used to
shorten the displayed path in $DBGMT/dynamic_debug/control via
ddebug_proc_show(), and in ddebug_change() to allow relative filenames
to be used in applied queries.  For example:

  ~# echo file kernel/freezer.c +p > $DBGMT/dynamic_debug/control

  kernel/freezer.c:128 [freezer]cancel_freezing p "  clean up: %s\012"

trim_prefix(path) insures common prefix before trimming it, so
out-of-tree module paths are shown as full absolute paths.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-24 12:48:55 -08:00
Jim Cromie
7281491c59 dynamic_debug: enlarge command/query write buffer
Current query write buffer is 256 bytes, on stack.  In comparison, the
ddebug_query boot-arg is 1024.  Allocate the buffer off heap, and
enlarge it to 4096 bytes, big enough for ~100 queries (at 40 bytes
each), and error out if not.  This makes it play nicely with large
query sets (to be added later).  The buffer should be enough for most
uses, and others should probably be split into subsets.

[jbaron@redhat.com: changed USER_BUF_PAGE from 4095 -> 4096 ]
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-24 12:48:55 -08:00
Jim Cromie
8bd6026e88 dynamic_debug: chop off comments in ddebug_tokenize
If a token begins with #, the remainder of query string is a comment,
so drop it.  Doing it here avoids '#' in quoted strings.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-24 12:48:54 -08:00
Jim Cromie
b5b78f8385 dynamic_debug: early return if _ddebug table is empty
If _ddebug table is empty (in a CONFIG_DYNAMIC_DEBUG build this
shouldn't happen), then warn (error?) and return early.  This skips
empty table scan and parsing of setup-string, including the pr_info
call noting the parse.  By inspection, copy return-code handling from
1st ddebug_add_module() callsite to 2nd.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-24 12:48:54 -08:00
Jim Cromie
820874c75e dynamic_debug: tighten up error checking on debug queries
Issue error when a match-spec is given multiple times in a rule.
Previous code kept last one, but was silent about it.  Docs imply only
one is allowed by saying match-specs are ANDed together, given that
module M cannot match both A and B.  Also error when last_line < 1st_line.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-24 12:48:53 -08:00
Jim Cromie
5ca7d2a6c5 dynamic_debug: describe_flags with '=[pmflt_]*'
Change describe_flags() to emit '=[pmflt_]+' for current callsite
flags, or just '=_' when they're disabled.  Having '=' in output
allows a more selective grep expression; in contrast '-' may appear
in filenames, line-ranges, and format-strings.  '=' also has better
mnemonics, saying; "the current setting is equal to <flags>".

This allows grep "=_" <dbgfs>/dynamic_debug/control to see disabled
callsites while avoiding the many occurrences of " = " seen in format
strings.

Enlarge flagsbufs to handle additional flag char, and alter
ddebug_parse_flags() to allow flags=0, so that user can turn off all
debug flags via:

  ~# echo =_ > <dbgfs>/dynamic_debug/control

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-24 12:48:52 -08:00
Jim Cromie
d6a238d250 dynamic_debug: drop explicit !=NULL checks
Convert 'if (x !=NULL)' checks into 'if (x)'.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-24 12:46:46 -08:00
Jim Cromie
ae27f86a21 dynamic_debug: pr_err() call should not depend upon verbosity
Issue keyword/parsing errors even w/o verbose set;
uncover otherwize mysterious non-functionality.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-24 12:46:45 -08:00
Jim Cromie
bc757f6f5b dynamic_debug: replace strcpy with strlcpy, in ddebug_setup_query()
Replace strcpy with strlcpy, and add define for the size constant.

[jbaron@redhat.com: Use DDEBUG_STRING_SIZE for overflow check]
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-24 12:46:45 -08:00
Jim Cromie
74df138d50 dynamic_debug: change verbosity at runtime
Allow changing dynamic_debug verbosity at run-time, to ease debugging
of ddebug queries as you add them, improving usability.

at boot time: dynamic_debug.verbose=1
at runtime:
root@voyage:~# echo 1 > /sys/module/dynamic_debug/parameters/verbose

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-24 12:46:45 -08:00
Jim Cromie
87e6f96833 dynamic_debug: drop enabled field from struct _ddebug, use _DPRINTK_FLAGS_PRINT
Currently any enabled dynamic-debug flag on a pr_debug callsite will
enable printing, even if _DPRINTK_FLAGS_PRINT is off.  Checking print
flag directly allows "-p" to disable callsites without fussing with
other flags, so the following disables everything, without altering
flags user may have set:

	echo -p > $DBGFS/dynamic_debug/control

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-24 12:46:44 -08:00
Jim Cromie
07100be7e0 dynamic_debug: fix whitespace complaints from scripts/cleanfile
Style cleanups.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-24 12:46:43 -08:00
Linus Torvalds
2d03423b23 Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
* 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (38 commits)
  mm: memory hotplug: Check if pages are correctly reserved on a per-section basis
  Revert "memory hotplug: Correct page reservation checking"
  Update email address for stable patch submission
  dynamic_debug: fix undefined reference to `__netdev_printk'
  dynamic_debug: use a single printk() to emit messages
  dynamic_debug: remove num_enabled accounting
  dynamic_debug: consolidate repetitive struct _ddebug descriptor definitions
  uio: Support physical addresses >32 bits on 32-bit systems
  sysfs: add unsigned long cast to prevent compile warning
  drivers: base: print rejected matches with DEBUG_DRIVER
  memory hotplug: Correct page reservation checking
  memory hotplug: Refuse to add unaligned memory regions
  remove the messy code file Documentation/zh_CN/SubmitChecklist
  ARM: mxc: convert device creation to use platform_device_register_full
  new helper to create platform devices with dma mask
  docs/driver-model: Update device class docs
  docs/driver-model: Document device.groups
  kobj_uevent: Ignore if some listeners cannot handle message
  dynamic_debug: make netif_dbg() call __netdev_printk()
  dynamic_debug: make netdev_dbg() call __netdev_printk()
  ...
2011-10-25 12:13:59 +02:00
Jason Baron
0feefd9786 dynamic_debug: fix undefined reference to `__netdev_printk'
Dynamic debug recently added support for netdev_printk.  It uses
__netdev_printk() to support this functionality.  However, when CONFIG_NET
is not set, we get the following error:

lib/built-in.o: In function `__dynamic_netdev_dbg':
(.text+0x9fda): undefined reference to `__netdev_printk'

Fix this by making the call to netdev_printk() contingent upon CONFIG_NET.
 We could have fixed this by defining netdev_printk() to a 'no-op' in the
!CONFIG_NET case.  However, this is not consistent with how the networking
layer uses netdev_printk.  For example, CONFIG_NET is not set,
netdev_printk() does not have a 'no-op' definition defined.

Signed-off-by: Jason Baron <jbaron@redhat.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-10-18 11:22:01 -07:00
Jason Baron
431625dac1 dynamic_debug: use a single printk() to emit messages
We were using KERN_CONT to combine messages with their prefix.  However,
KERN_CONT is not smp safe, in the sense that it can interleave messages.
This interleaving can result in printks coming out at the wrong loglevel.
With the high frequency of printks that dynamic debug can produce this is
not desirable.

So make dynamic_emit_prefix() fill a char buf[64] instead of doing a
printk directly.  If we enable printing out of function, module, line, or
pid info, they are placed in this 64 byte buffer.  In my testing 64 bytes
was enough size to fulfill all requests.  Even if it's not, we can match
up the printk itself to see where it's from, so to me this is no big deal.

[akpm@linux-foundation.org: convert dangerous macro to C]
Signed-off-by: Jason Baron <jbaron@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-10-18 11:22:00 -07:00
Jason Baron
bd22c01e84 dynamic_debug: remove num_enabled accounting
The num_enabled accounting isn't actually used anywhere - remove them.

Signed-off-by: Jason Baron <jbaron@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-10-18 11:22:00 -07:00
Jesper Juhl
c9bab38f70 Remove unneeded version.h include from lib/
This patch removes an unneeded include of linux/version.h from
lib/dynamic_debug.c - identified by 'make versioncheck'.
This is the only file in lib/ with this issue.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-09-15 14:57:05 +02:00
Jason Baron
ffa10cb47a dynamic_debug: make netdev_dbg() call __netdev_printk()
Previously, if dynamic debug was enabled netdev_dbg() was using
dynamic_dev_dbg() to print out the underlying msg. Fix this by making
sure netdev_dbg() uses __netdev_printk().

Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-22 18:23:06 -07:00
Joe Perches
4ad275e5cb dynamic_debug: Convert printks to pr_<level>
Add pr_fmt(fmt) with __func__.
Converts "ddebug:" prefix to "dynamic_debug:".

Most likely the if (verbose) outputs could
also be converted from pr_info to pr_debug.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-22 18:23:05 -07:00
Joe Perches
5b2ebce482 dynamic_debug: Remove uses of KERN_CONT in dynamic_emit_prefix
Multiple printks with KERN_CONT can be interleaved by
other printks.  Reduce the likelihood of that interleaving
by consolidating multiple calls to printk.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-22 18:23:04 -07:00
Joe Perches
6c2140ee0e dynamic_debug: Consolidate prefix output to single routine
Adding dynamic_dev_dbg duplicated prefix output.
Consolidate that output to a single routine.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-22 18:23:04 -07:00
Joe Perches
cbc4663552 dynamic_debug: Add __dynamic_dev_dbg
Unlike dynamic_pr_debug, dynamic uses of dev_dbg can not
currently add task_pid/KBUILD_MODNAME/__func__/__LINE__
to selected debug output.

Add a new function similar to dynamic_pr_debug to
optionally emit these prefixes.

Cc: Aloisio Almeida <aloisio.almeida@openbossa.org>
Noticed-by: Aloisio Almeida <aloisio.almeida@openbossa.org>
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-22 18:23:04 -07:00
Greg Kroah-Hartman
e8d9792aa5 dynamic_debug: add #include <linux/sched.h>
This fixes a build breakage caused by
8ba6ebf583 "Dynamic debug: Add more flags"

Cc: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-02-03 15:59:58 -08:00