This patch updates PEBS event constraints for Intel Atom, Nehalem, Westmere.
This patch also reorganizes the PEBS format/constraint detection code. It is
now based on processor model and not PEBS format. Two processors may use the
same PEBS format without have the same list of PEBS events.
In this second version, we simplified the initialization of the PEBS
constraints by leveraging the existing switch() statement in perf_event_intel.c.
We also renamed the constraint tables to be more consistent with regular
constraints.
In this 3rd version, we drop BR_INST_RETIRED.MISPRED from Intel Atom as it does
not seem to work. Use MISPREDICTED_BRANCH_RETIRED instead. Also add FP_ASSIST.*
o both Intel Nehalem and Westmere. I misssed those in the earlier patches.
Events were tested using libpfm4 perf_examples.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <4d6e6b02.815bdf0a.637b.07a7@mx.google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Li Zefan reported that the jump label code sleeps and we're calling it
under a spinlock, *fail* ;-)
Reported-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In the failure path, we call perf_detach_cgroup(), but we didn't
call perf_get_cgroup() prio to it.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <4D6F346E.9070606@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In perf_cgroup_connect(), fput_light() is missing in a failure path.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <4D6F3461.6060406@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Currently, the event is not initialized if pmu is found in idr. This
never causes bug just because now no pmu is associated with the idr
id.
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1298812411.2699.9.camel@localhost>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
PyVarObject_HEAD_INIT is undefined in python 2.5, resulting
in a build crash:
util/python.c:81: attention : déclaration implicite de la fonction « «PyVarObject_HEAD_INIT» »
util/python.c:82: erreur: request for member «tp_name» in something not a structure or union
util/python.c:117: erreur: request for member «tp_name» in something not a structure or union
util/python.c:146: erreur: request for member «tp_name» in something not a structure or union
util/python.c:177: erreur: request for member «tp_name» in something not a structure or union
util/python.c:290: erreur: request for member «tp_name» in something not a structure or union
util/python.c:359: erreur: request for member «tp_name» in something not a structure or union
util/python.c:532: erreur: request for member «tp_name» in something not a structure or union
util/python.c:761: erreur: request for member «tp_name» in something not a structure or union
error: command 'gcc' failed with exit status 1
make: *** [python/perf.so] Erreur 1
We can fix that by defining PyVarObject_HEAD_INIT as a wrapper on
PyObject_HEAD_INIT, thanks to a trick found on biopython:
d4eaf57946
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
<ctype.h> is included first without _GNU_SOURCE, so it ends up
including <string.h> without declaring strndup(). And further
<string.h> declarations, even with _GNU_SOURCE defined, are
of course without effect.
Therefore:
util/strfilter.c: Dans la fonction «strfilter_node__new» :
util/strfilter.c:134: attention : déclaration implicite de la fonction « «strndup» »
util/strfilter.c:134: attention : incompatible implicit declaration of built-in function «strndup»
make: *** [util/strfilter.o] Erreur 1
Just don't include ctype.h as it doesn't appear to be necessary
anyway.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
We currently set the filters after we mmap the events, this is a
race that let undesired events record themselves in the buffer before
we had the time to set the filters.
So set the filters before they can be recorded. That also librarizes
the filters setting so that filtering can be done more easily
from other tools than perf record later.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
This patch adds basic SandyBridge support, including hardware
cache events and PEBS events support.
It has been tested on SandyBridge CPUs with perf stat and also
with PEBS based profiling - both work fine.
The patch does not affect other models.
v2 -> v3:
- fix PEBS event 0xd0 with right umask combinations
- move snb pebs constraint assignment to intel_pmu_init
v1 -> v2:
- add more raw and PEBS events constraints
- use offcore events for LLC-* cache events
- remove the call to Nehalem workaround enable_all function
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Andi Kleen <andi@firstfloor.org>
LKML-Reference: <1299072424.2175.24.camel@localhost>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Using ui__warning, that will, in --tui, show a window with the message,
waiting for the user to press Ok.
Also run exit_browser() to let newt do its final cleaning of the screen.
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
By taking the ui__lock so that no other screen updates take place while
waiting for the user.
That was happening when handling an invalid --vmlinux parameter in 'perf
top --tui', with the screen refresh routine repainting the screen and
removing the warning window.
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fixing a SEGV. An empty list could happen when not being able to resolve
symbols, for instance when --vmlinux invalid-file is used.
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The ec5761e cset introduced the symfs feature with a bug for loading vmlinux
files that ended up causing this failure:
[root@emilia v2.6.38-rc5+]# strace -e trace=open perf top --vmlinux ./vmlinux 2>&1 | tail -3
open("/./vmlinux", O_RDONLY) = -1 ENOENT (No such file or directory)
./vmlinux with build id b9266bf40e98dadb5d43a2f3e95d3c5d4aff46dc not found, continuing without symbols
The ./vmlinux file can't be used
[root@emilia v2.6.38-rc5+]#
Remove the extra slash, just like is done in the DSO__ORIG_DSO handling in
dso__load() and other parts of the ec5761e cset.
Reported-by: Ingo Molnar <mingo@elte.hu>
Cc: David Ahern <daahern@cisco.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently numcpus is determined in pid_put_sample which is only
called on sched_switch/sched_wakeup sample processing.
On a machine with a lot cpus I often saw the last cpu missing.
Check for (max) numcpus on every event happening and in the
beginning. -> fixes the issue for me.
Signed-off-by: Thomas Renninger <trenn@suse.de>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: lenb@kernel.org
LKML-Reference: <1298842606-55712-6-git-send-email-trenn@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This fix is needed for eye of gnome and firefox svg viewers.
Only Inkscape can handle the broken case.
Compare with the other svg_legenda_box declarations, looks
like a typo slipped in at this place.
Signed-off-by: Thomas Renninger <trenn@suse.de>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: lenb@kernel.org
LKML-Reference: <1298842606-55712-5-git-send-email-trenn@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Needed because we were only showing the title in ui_browser__show,
not in ui_browser__run, and in the run loop we may be calling other
browsers that would then change the title, when we go back to the
previous browser, we need to redraw the title.
We could have done this as the Newt help line, with pop, etc, but I
don't think its worth, doing it explicitely, when needed (some browsers
may not use the title area at all) seems enough/more flexible.
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The left key was exiting 'perf top --tui' when it really shouldn't, it
was too easy to leave the live annotation window and then press one too
many <- and get out of the tool altogether.
Do just like the report TUI does, ignore the left key for exit and also
ask the user when pressing ESC if that is really what is wanted.
Reported-by: Mike Galbraith <efault@gmx.de>
Suggested-by: Ingo Molnar <mingo@elte.hu>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In both --tui and --stdio, in 'annotate', 'top', 'report' when trying to
annotate a kernel symbol having just access to a kallsyms file, that
doesn't have the DWARF info needed for annotation.
Suggested-by: Ingo Molnar <mingo@elte.hu>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There is no point in us having different code paths for nmi and !nmi
here, so remove the !nmi one.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patches ensures that we do not end up calling
perf_cgroup_from_task() when there is no cgroup event.
This avoids potential RCU and locking issues.
The change in perf_cgroup_set_timestamp() ensures we
check against ctx->nr_cgroups. It also avoids calling
perf_clock() tiwce in a row. It also ensures we do need
to grab ctx->lock before calling the function.
We drop update_cgrp_time() from task_clock_event_read()
because it is not needed. This also avoids having to
deal with perf_cgroup_from_task().
Thanks to Peter Zijlstra for his help on this.
Signed-off-by: Stephane Eranian <eranian@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <4d5e76b8.815bdf0a.7ac3.774f@mx.google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This is not a problem when we're not at the bottom of the active symbols
list, so was not noticed, but at the end of the screen it falls apart.
Fix it by adjusting the ui_browser indexes according to the new number
of entries in the rb_tree and by seeking from the start of the rb_tree
to find the new symbol at the top of the screen.
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* 'for-2639-rc4/i2c-fixes' of git://git.fluff.org/bjdooks/linux:
i2c-omap: fixup commit cb527ede1b whitespace
i2c-omap: Double clear of ARDY status in IRQ handler
i2c-omap: fix build for !CONFIG_SUSPEND
i2c-omap: fix static suspend vs. runtime suspend
i2c-stu300: make sure adapter-name is terminated
This errata occurs when the ARDY interrupt generation is enabled.
At the begining of every new transaction the ARDY interrupt is cleared.
On continuous i2c transactions where after clearing the ARDY bit from
I2C_STAT register (clearing the interrupt), the IRQ line is reasserted and the
I2C_STAT[ARDY] bit set again on 1. In fact, the ARDY status bit is not cleared
at the write access to I2C_STAT[ARDY] and only the IRQ line is deasserted and
then reasserted. This is not captured in the usual errata documents.
The workaround is to have a double clear of ARDY status in irq handler.
Signed-off-by: Richard woodruff <r-woodruff2@ti.com>
Signed-off-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
When runtime PM is enabled, each OMAP i2c device is suspended after
each i2c xfer. However, there are two cases when the static suspend
methods must be used to ensure the devices are suspended:
1) runtime PM is disabled, either at compile time or dynamically
via /sys/devices/.../power/control.
2) an i2c client driver uses i2c during it's suspend callback, thus
leaving the i2c driver active (NOTE: runtime suspend transitions are
disabled during system suspend, so i2c activity during system
suspend will runtime resume the device, but not runtime (re)suspend it.)
Since the actual work to suspend the device is handled by the
subsytem, call the bus methods to take care of it.
NOTE: This takes care of a known suspend problem on OMAP3 where the
TWL RTC driver does i2c xfers during its suspend path leaving the i2c
driver in an active state (since runtime suspend transistions are
disabled.)
Signed-off-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Use strlcpy instead of strncpy.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Linus Walleij <linus.walleij@stericsson.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* 'urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/brodo/pcmcia-2.6:
pcmcia: re-enable Zoomed Video support
cm4000_cs: Fix undefined ops warning
pcmcia vs. MECR on pxa25x/sa1111
drivers/char/pcmcia/ipwireless/main.c: Convert release_resource to release_region/release_mem_region
* 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
genirq: Disable the SHIRQ_DEBUG call in request_threaded_irq for now
genirq: Prevent access beyond allocated_irqs bitmap
* 'fix/asoc' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
ASoC: Ensure supplies are maintained for force enabled widgets
ASoC: WM8994: Improve playback robustness
ASoC: WM8994: Improve robustness in some use cases
ASoC: WM8903: Fix mic detection enable logic
ASoC: WM8903: Fix mic detection register definitions
ASoC: CX20442: fix wrong reg_cache_default content
ASoC: Sync initial widget state with hardware
Building with CONFIG_KERNEL_XZ results in the following:
# Untracked files:
# (use "git add <file>..." to include in what will be committed)
#
# arch/x86/boot/compressed/vmlinux.bin.xz
So ignore xz-compressed files at the top level like we already do for
other compression types.
Signed-off-by: Romain Francoise <romain@orebokech.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now one has just to press the right key, 'a' or Enter on the main 'perf
top --tui' screen to live annotate the symbol under the cursor.
The annotate window starts centered on the hottest line (the one with
most samples so far) then TAB and shift+TAB can be used to go to the
prev/next hot line.
Pressing 'H' at any point will center again the screen on the hottest
line.
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
While fixing an error propagating problem in f809b25 I added two
redundant checks.
I did that because I didn't expect the checks to be on the while and for
loop condition expression, where they are tested before we run the loop,
where the 'ret' variable is set.
So remove it from there and leave it just after it is actually set,
eliminating unneded tests.
Reported-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The kernel refuses mmapping an event with the inherit flag set for
something that is systemwide (cpu == -1), and the evsel layer got this
reversed at some point, fix it.
The symtom was that the --pid and --tid parameters for 'perf record' and
'perf top' returned with -EINVAL, like:
# /tmp/build-perf/perf record -v -fo/tmp/perf.data -p 1042
Warning: ... trying to fall back to cpu-clock-ticks
Fatal: failed to mmap with 22 (Invalid argument)
Reported-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ecryptfs/ecryptfs-2.6:
eCryptfs: Copy up lower inode attrs in getattr
ecryptfs: read on a directory should return EISDIR if not supported
eCryptfs: Handle NULL nameidata pointers
eCryptfs: Revert "dont call lookup_one_len to avoid NULL nameidata"
There are two hunks in this patch that stops probe processing as soon as one
error is found, breaking out of loops, the other fix an error propagation that
should return a negative error number but instead was returning the result of
"ret < 0", which is 1 and thus made several error checks fail because they test
agains < 0.
The problem could be triggered by asking for a variable that was optimized out,
fact that should stop the whole probe processing but instead was segfaulting
while installing broken probes:
[root@emilia ~]# probe perf_mmap:55 user_lock_limit
Failed to find the location of user_lock_limit at this address.
Perhaps, it has been optimized out.
Failed to find 'user_lock_limit' in this function.
Add new events:
probe:perf_mmap (on perf_mmap:55 with user_lock_limit)
probe:perf_mmap_1 (on perf_mmap:55 with user_lock_limit)
Segmentation fault (core dumped)
[root@emilia ~]# perf probe -l
probe:perf_mmap (on perf_mmap:55@git/linux/kernel/perf_event.c with user_lock_limit)
probe:perf_mmap_1 (on perf_mmap:55@git/linux/kernel/perf_event.c with user_lock_limit)
[root@emilia ~]#
After the fix:
[root@emilia ~]# probe perf_mmap:55 user_lock_limit
Failed to find the location of user_lock_limit at this address.
Perhaps, it has been optimized out.
Failed to find 'user_lock_limit' in this function.
Error: Failed to add events. (-2)
[root@emilia ~]#
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The current code does not follow Intel documentation: It misses some things
and does other, undocumented things. This causes wrong backlight values in
certain conditions. Instead of adding tricky code handling badly documented
and rare corner cases, don't handle combination mode specially at all. This
way PCI_LBPC is never touched and weird things shouldn't happen.
If combination mode is enabled, then the only downside is that changing the
brightness has a greater granularity (the LBPC value), but LBPC is at most
254 and the maximum is in the thousands, so this is no real functional loss.
A potential problem with not handling combined mode is that a brightness of
max * PCI_LBPC is not bright enough. However, this is very unlikely because
from the documentation LBPC seems to act as a scaling factor and doesn't look
like it's supposed to be changed after boot. The value at boot should always
result in a bright enough screen.
IMPORTANT: However, although usually the above is true, it may not be when
people ran an older (2.6.37) kernel which messed up the LBPC register, and
they are unlucky enough to have a BIOS that saves and restores the LBPC value.
Then a good kernel may seem to not work: Max brightness isn't bright enough.
If this happens people should boot back into the old kernel, set brightness
to the maximum, and then reboot. After that everything should be fine.
For more information see the below links. This fixes bugs:
http://bugzilla.kernel.org/show_bug.cgi?id=23472http://bugzilla.kernel.org/show_bug.cgi?id=25072
Signed-off-by: Indan Zupancic <indan@nul.nu>
Tested-by: Alex Riesen <raa.lkml@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We force particular alignment when we generate attribute structures
when generation MODULE_VERSION() data and we need to make sure that
this alignment is followed when we iterate over these structures,
otherwise we may crash on platforms whose natural alignment is not
sizeof(void *), such as m68k.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Dmitry Torokhov <dtor@vmware.com>
[ There are more issues here, but the fixes are incredibly ugly - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Stephane Eranian