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2010-05-20kgdb: Add the ability to schedule a breakpoint via a taskletJason Wessel1-0/+26
Some kgdb I/O modules require the ability to create a breakpoint tasklet, such as kgdboc and external modules such as kgdboe. The breakpoint tasklet is used as an asynchronous entry point into the debugger which will have a different function scope than the current execution path where it might not be safe to have an inline breakpoint. This is true of some of the kgdb I/O drivers which share code with kgdb and rest of the kernel users. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20x86,kgdb: Add low level debug hookJason Wessel1-1/+1
The only way the debugger can handle a trap in inside rcu_lock, notify_die, or atomic_notifier_call_chain without a triple fault is to have a low level "first opportunity handler" in the int3 exception handler. Generally this will be something the vast majority of folks will not need, but for those who need it, it is added as a kernel .config option called KGDB_LOW_LEVEL_TRAP. CC: Ingo Molnar <mingo@elte.hu> CC: Thomas Gleixner <tglx@linutronix.de> CC: H. Peter Anvin <hpa@zytor.com> CC: x86@kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20kgdb: remove post_primary_code referencesJason Wessel1-8/+0
Remove all the references to the kgdb_post_primary_code. This function serves no useful purpose because you can obtain the same information from the "struct kgdb_state *ks" from with in the debugger, if for some reason you want the data. Also remove the unintentional duplicate assignment for ks->ex_vector. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20kgdboc,keyboard: Keyboard driver for kdb with kgdbJason Wessel2-0/+213
This patch adds in the kdb PS/2 keyboard driver. This was mostly a direct port from the original kdb where I cleaned up the code against checkpatch.pl and added the glue to stitch it into kgdb. This patch also enables early kdb debug via kgdbwait and the keyboard. All the access to configure kdb using either a serial console or the keyboard is done via kgdboc. If you want to use only the keyboard and want to break in early you would add to your kernel command arguments: kgdboc=kbd kgdbwait If you wanted serial and or the keyboard access you could use: kgdboc=kbd,ttyS0 You can also configure kgdboc as a kernel module or at run time with the sysfs where you can activate and deactivate kgdb. Turn it on: echo kbd,ttyS0 > /sys/module/kgdboc/parameters/kgdboc Turn it off: echo "" > /sys/module/kgdboc/parameters/kgdboc Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2010-05-20kgdb: gdb "monitor" -> kdb passthroughJason Wessel5-6/+34
One of the driving forces behind integrating another front end (kdb) to the debug core is to allow front end commands to be accessible via gdb's monitor command. It is true that you could write gdb macros to get certain data, but you may want to just use gdb to access the commands that are available in the kdb front end. This patch implements the Rcmd gdb stub packet. In gdb you access this with the "monitor" command. For instance you could type "monitor help", "monitor lsmod" or "monitor ps A" etc... There is no error checking or command restrictions on what you can and cannot access at this point. Doing something like trying to set breakpoints with the monitor command is going to cause nothing but problems. Perhaps in the future only the commands that are actually known to work with the gdb monitor command will be available. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20kgdb,8250,pl011: Return immediately from console pollJason Wessel3-6/+43
The design of the kdb shell requires that every device that can provide input to kdb have a polling routine that exits immediately if there is no character available. This is required in order to get the page scrolling mechanism working. Changing the kernel debugger I/O API to require all polling character routines to exit immediately if there is no data allows the kernel debugger to process multiple input channels. NO_POLL_CHAR will be the return code to the polling routine when ever there is no character available. CC: linux-serial@vger.kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20kgdb: core changes to support kdbJason Wessel3-17/+150
These are the minimum changes to the kgdb core in order to enable an API to connect a new front end (kdb) to the debug core. This patch introduces the dbg_kdb_mode variable controls where the user level I/O is routed. It will be routed to the gdbstub (kgdb) or to the kdb front end which is a simple shell available over the kgdboc connection. You can switch back and forth between kdb or the gdb stub mode of operation dynamically. From gdb stub mode you can blindly type "$3#33", or from the kdb mode you can enter "kgdb" to switch to the gdb stub. The logic in the debug core depends on kdb to look for the typical gdb connection sequences and return immediately with KGDB_PASS_EVENT if a gdb serial command sequence is detected. That should allow a reasonably seamless transition between kdb -> gdb without leaving the kernel exception state. The two gdb serial queries that kdb is responsible for detecting are the "?" and "qSupported" packets. CC: Ingo Molnar <mingo@elte.hu> Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Martin Hicks <mort@sgi.com>
2010-05-20kdb: core for kgdb back end (2 of 2)Jason Wessel5-2/+86
This patch contains the hooks and instrumentation into kernel which live outside the kernel/debug directory, which the kdb core will call to run commands like lsmod, dmesg, bt etc... CC: linux-arch@vger.kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Martin Hicks <mort@sgi.com>
2010-05-20kdb: core for kgdb back end (1 of 2)Jason Wessel11-0/+5854
This patch contains only the kdb core. Because the change set was large, it was split. The next patch in the series includes the instrumentation into the core kernel which are mainly helper functions for kdb. This work is directly derived from kdb v4.4 found at: ftp://oss.sgi.com/projects/kdb/download/v4.4/ The kdb internals have been re-organized to make them mostly platform independent and to connect everything to the debug core which is used by gdbstub (which has long been known as kgdb). The original version of kdb was 58,000 lines worth of changes to support x86. From that implementation only the kdb shell, and basic commands for memory access, runcontrol, lsmod, and dmesg where carried forward. This is a generic implementation which aims to cover all the current architectures using the kgdb core: ppc, arm, x86, mips, sparc, sh and blackfin. More archictectures can be added by implementing the architecture specific kgdb functions. [mort@sgi.com: Compile fix with hugepages enabled] [mort@sgi.com: Clean breakpoint code renaming kdba_ -> kdb_] [mort@sgi.com: fix new line after printing registers] [mort@sgi.com: Remove the concept of global vs. local breakpoints] [mort@sgi.com: Rework kdb_si_swapinfo to use more generic name] [mort@sgi.com: fix the information dump macros, remove 'arch' from the names] [sfr@canb.auug.org.au: include fixup to include linux/slab.h] CC: linux-arch@vger.kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Martin Hicks <mort@sgi.com>
2010-05-20Separate the gdbstub from the debug coreJason Wessel4-957/+1029
Split the former kernel/kgdb.c into debug_core.c which contains the kernel debugger exception logic and to the gdbstub.c which contains the logic for allowing gdb to talk to the debug core. This also created a private include file called debug_core.h which contains all the definitions to glue the debug_core to any other debugger connections. CC: Ingo Molnar <mingo@elte.hu> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20Move kernel/kgdb.c to kernel/debug/debug_core.cJason Wessel3-1/+7
Move kgdb.c in preparation to separate the gdbstub from the debug core and exception handling. CC: Ingo Molnar <mingo@elte.hu> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20wait_event_interruptible_locked() interfaceMichal Nazarewicz1-0/+1
New wait_event_interruptible{,_exclusive}_locked{,_irq} macros added. They work just like versions without _locked* suffix but require the wait queue's lock to be held. Also __wake_up_locked() is now exported as to pair it with the above macros. The use case of this new facility is when one uses wait queue's lock to protect a data structure. This may be advantageous if the structure needs to be protected by a spinlock anyway. In particular, with additional spinlock the following code has to be used to wait for a condition: spin_lock(&data.lock); ... for (ret = 0; !ret && !(condition); ) { spin_unlock(&data.lock); ret = wait_event_interruptible(data.wqh, (condition)); spin_lock(&data.lock); } ... spin_unlock(&data.lock); This looks bizarre plus wait_event_interruptible() locks the wait queue's lock anyway so there is a unlock+lock sequence where it could be avoided. To avoid those problems and benefit from wait queue's lock, a code similar to the following should be used: /* Waiting */ spin_lock(&data.wqh.lock); ... ret = wait_event_interruptible_locked(data.wqh, (condition)); ... spin_unlock(&data.wqh.lock); /* Waiting exclusively */ spin_lock(&data.whq.lock); ... ret = wait_event_interruptible_exclusive_locked(data.whq, (condition)); ... spin_unlock(&data.whq.lock); /* Waking up */ spin_lock(&data.wqh.lock); ... wake_up_locked(&data.wqh); ... spin_unlock(&data.wqh.lock); When spin_lock_irq() is used matching versions of macros need to be used (*_locked_irq()). Signed-off-by: Michal Nazarewicz <m.nazarewicz@samsung.com> Cc: Kyungmin Park <kyungmin.park@samsung.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Takashi Iwai <tiwai@suse.de> Cc: David Howells <dhowells@redhat.com> Cc: Andreas Herrmann <andreas.herrmann3@amd.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Mike Galbraith <efault@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-20perf: Fix forgotten preempt_enable by nested writersFrederic Weisbecker1-1/+2
A writer that gets a reference to the buffer handle disables preemption. When we put that reference, we check if we are the outer most writer and if not, we simply return and defer the head update to the outer most writer. The problem here is that preemption is only reenabled by the outer most, that produces preemption count imbalance for every nested writer that exit. So just don't forget to always re-enable preemption when we put the buffer reference, whoever we are. Fixes lots of sleeping in atomic warnings, visible with lock events recording. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Stephane Eranian <eranian@google.com> Cc: Robert Richter <robert.richter@amd.com>
2010-05-20Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/inputLinus Torvalds1-1/+22
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (40 commits) Input: psmouse - small formatting changes to better follow coding style Input: synaptics - set dimensions as reported by firmware Input: elantech - relax signature checks Input: elantech - enforce common prefix on messages Input: wistron_btns - switch to using kmemdup() Input: usbtouchscreen - switch to using kmemdup() Input: do not force selecting i8042 on Moorestown Input: Documentation/sysrq.txt - update KEY_SYSRQ info Input: 88pm860x_onkey - remove invalid irq number assignment Input: i8042 - add a PNP entry to the aux device list Input: i8042 - add some extra PNP keyboard types Input: wm9712 - fix wm97xx_set_gpio() logic Input: add keypad driver for keys interfaced to TCA6416 Input: remove obsolete {corgi,spitz,tosa}kbd.c Input: kbtab - do not advertise unsupported events Input: kbtab - simplify kbtab_disconnect() Input: kbtab - fix incorrect size parameter in usb_buffer_free Input: acecad - don't advertise mouse events Input: acecad - fix some formatting issues Input: acecad - simplify usb_acecad_disconnect() ... Trivial conflict in Documentation/feature-removal-schedule.txt
2010-05-20Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivialLinus Torvalds1-1/+1
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (44 commits) vlynq: make whole Kconfig-menu dependant on architecture add descriptive comment for TIF_MEMDIE task flag declaration. EEPROM: max6875: Header file cleanup EEPROM: 93cx6: Header file cleanup EEPROM: Header file cleanup agp: use NULL instead of 0 when pointer is needed rtc-v3020: make bitfield unsigned PCI: make bitfield unsigned jbd2: use NULL instead of 0 when pointer is needed cciss: fix shadows sparse warning doc: inode uses a mutex instead of a semaphore. uml: i386: Avoid redefinition of NR_syscalls fix "seperate" typos in comments cocbalt_lcdfb: correct sections doc: Change urls for sparse Powerpc: wii: Fix typo in comment i2o: cleanup some exit paths Documentation/: it's -> its where appropriate UML: Fix compiler warning due to missing task_struct declaration UML: add kernel.h include to signal.c ...
2010-05-20Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6Linus Torvalds8-431/+456
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6: PM: PM QOS update fix Freezer / cgroup freezer: Update stale locking comments PM / platform_bus: Allow runtime PM by default i2c: Fix bus-level power management callbacks PM QOS update PM / Hibernate: Fix block_io.c printk warning PM / Hibernate: Group swap ops PM / Hibernate: Move the first_sector out of swsusp_write PM / Hibernate: Separate block_io PM / Hibernate: Snapshot cleanup FS / libfs: Implement simple_write_to_buffer PM / Hibernate: document open(/dev/snapshot) side effects PM / Runtime: Add sysfs debug files PM: Improve device power management document PM: Update device power management document PM: Allow runtime_suspend methods to call pm_schedule_suspend() PM: pm_wakeup - switch to using bool
2010-05-20Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wqLinus Torvalds1-1/+35
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: workqueue: change cancel_work_sync() to clear work->data workqueue: warn about flush_scheduled_work()
2010-05-20Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6Linus Torvalds4-54/+5
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6: (61 commits) KEYS: Return more accurate error codes LSM: Add __init to fixup function. TOMOYO: Add pathname grouping support. ima: remove ACPI dependency TPM: ACPI/PNP dependency removal security/selinux/ss: Use kstrdup TOMOYO: Use stack memory for pending entry. Revert "ima: remove ACPI dependency" Revert "TPM: ACPI/PNP dependency removal" KEYS: Do preallocation for __key_link() TOMOYO: Use mutex_lock_interruptible. KEYS: Better handling of errors from construct_alloc_key() KEYS: keyring_serialise_link_sem is only needed for keyring->keyring links TOMOYO: Use GFP_NOFS rather than GFP_KERNEL. ima: remove ACPI dependency TPM: ACPI/PNP dependency removal selinux: generalize disabling of execmem for plt-in-heap archs LSM Audit: rename LSM_AUDIT_NO_AUDIT to LSM_AUDIT_DATA_NONE CRED: Holding a spinlock does not imply the holding of RCU read lock SMACK: Don't #include Ext2 headers ...
2010-05-20Merge branch 'perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into perf/coreIngo Molnar48-1410/+2153
2010-05-20perf: Comply with new rcu checks APIFrederic Weisbecker1-12/+46
The software events hlist doesn't fully comply with the new rcu checks api. We need to consider three different sides that access the hlist: - the hlist allocation/release side. This side happens when an events is created or released, accesses to the hlist are serialized under the cpuctx mutex. - the events insertion/removal in the hlist. This side is always serialized against the above one. The hlist is always present during such operations. This side happens when a software event is scheduled in/out. The serialization that ensures the software event is really attached to the context is made under the ctx->lock. - events triggering. This is the read side, it can happen concurrently with any update side. This patch deals with them one by one and anticipates with the separate rcu mem space patches in preparation. This patch fixes various annoying rcu warnings. Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Paul Mackerras <paulus@samba.org>
2010-05-19Merge branch 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tipLinus Torvalds7-286/+312
* 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: clocksource: Add clocksource_register_hz/khz interface posix-cpu-timers: Optimize run_posix_cpu_timers() time: Remove xtime_cache mqueue: Convert message queue timeout to use hrtimers hrtimers: Provide schedule_hrtimeout for CLOCK_REALTIME timers: Introduce the concept of timer slack for legacy timers ntp: Remove tickadj ntp: Make time_adjust static time: Add xtime, wall_to_monotonic to feature-removal-schedule timer: Try to survive timer callback preempt_count leak timer: Split out timer function call timer: Print function name for timer callbacks modifying preemption count time: Clean up warp_clock() cpu-timers: Avoid iterating over all threads in fastpath_timer_check() cpu-timers: Change SIGEV_NONE timer implementation cpu-timers: Return correct previous timer reload value cpu-timers: Cleanup arm_timer() cpu-timers: Simplify RLIMIT_CPU handling
2010-05-19Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tipLinus Torvalds3-33/+119
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: genirq: Clear CPU mask in affinity_hint when none is provided genirq: Add CPU mask affinity hint genirq: Remove IRQF_DISABLED from core code genirq: Run irq handlers with interrupts disabled genirq: Introduce request_any_context_irq() genirq: Expose irq_desc->node in proc/irq Fixed up trivial conflicts in Documentation/feature-removal-schedule.txt
2010-05-19cpumask: fix compat getaffinityKOSAKI Motohiro1-14/+11
Commit a45185d2d "cpumask: convert kernel/compat.c" broke libnuma, which abuses sched_getaffinity to find out NR_CPUS in order to parse /sys/devices/system/node/node*/cpumap. On NUMA systems with less than 32 possibly CPUs, the current compat_sys_sched_getaffinity now returns '4' instead of the actual NR_CPUS/8, which makes libnuma bail out when parsing the cpumap. The libnuma call sched_getaffinity(0, bitmap, 4096) at first. It mean the libnuma expect the return value of sched_getaffinity() is either len argument or NR_CPUS. But it doesn't expect to return nr_cpu_ids. Strictly speaking, userland requirement are 1) Glibc assume the return value mean the lengh of initialized of mask argument. E.g. if sched_getaffinity(1024) return 128, glibc make zero fill rest 896 byte. 2) Libnuma assume the return value can be used to guess NR_CPUS in kernel. It assume len-arg<NR_CPUS makes -EINVAL. But it try len=4096 at first and 4096 is always bigger than NR_CPUS. Then, if we remove strange min_length normalization, we never hit -EINVAL case. sched_getaffinity() already solved this issue. This patch adapts compat_sys_sched_getaffinity() to match the non-compat case. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Arnd Bergmann <arnd@arndb.de> Reported-by: Ken Werner <ken.werner@web.de> Cc: stable@kernel.org Cc: Andi Kleen <andi@firstfloor.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-19Merge branch 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6Linus Torvalds1-2/+3
* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6: (24 commits) [S390] drivers/s390/char: Use kmemdup [S390] drivers/s390/char: Use kstrdup [S390] debug: enable exception-trace debug facility [S390] s390_hypfs: Add new attributes [S390] qdio: remove API wrappers [S390] qdio: set correct bit in dsci [S390] qdio: dont convert timestamps to microseconds [S390] qdio: remove memset hack [S390] qdio: prevent starvation on PCI devices [S390] qdio: count number of qdio interrupts [S390] user space fault: report fault before calling do_exit [S390] topology: expose core identifier [S390] dasd: remove uid from devmap [S390] dasd: add dynamic pav toleration [S390] vdso: add missing vdso_install target [S390] vdso: remove redundant check for CONFIG_64BIT [S390] avoid default_llseek in s390 drivers [S390] vmcp: disallow modular build [S390] add breaking event address for user space [S390] virtualization aware cpu measurement ...
2010-05-19Merge commit 'v2.6.34' into nextDmitry Torokhov14-38/+108
2010-05-19module: drop the lock while waiting for module to complete initialization.Rusty Russell1-22/+37
This fixes "gave up waiting for init of module libcrc32c." which happened at boot time due to multiple parallel module loads. The problem was a deadlock: we wait for a module to finish initializing, but we keep the module_lock mutex so it can't complete. In particular, this could reasonably happen if a module does a request_module() in its initialization routine. So we change use_module() to return an errno rather than a bool, and if it's -EBUSY we drop the lock and wait in the caller, then reaquire the lock. Reported-by: Brandon Philips <brandon@ifup.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Tested-by: Brandon Philips <brandon@ifup.org>
2010-05-19panic: Add taint flag TAINT_FIRMWARE_WORKAROUND ('I')Ben Hutchings1-0/+2
This taint flag will initially be used when warning about invalid ACPI DMAR tables. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-19panic: Allow warnings to set different taint flagsBen Hutchings1-4/+20
WARN() is used in some places to report firmware or hardware bugs that are then worked-around. These bugs do not affect the stability of the kernel and should not set the flag for TAINT_WARN. To allow for this, add WARN_TAINT() and WARN_TAINT_ONCE() macros that take a taint number as argument. Architectures that implement warnings using trap instructions instead of calls to warn_slowpath_*() now implement __WARN_TAINT(taint) instead of __WARN(). Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Acked-by: Helge Deller <deller@gmx.de> Tested-by: Paul Mundt <lethal@linux-sh.org> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-19mutex: Fix optimistic spinning vs. BKLTony Breeds1-0/+7
Currently, we can hit a nasty case with optimistic spinning on mutexes: CPU A tries to take a mutex, while holding the BKL CPU B tried to take the BLK while holding the mutex This looks like a AB-BA scenario but in practice, is allowed and happens due to the auto-release on schedule() nature of the BKL. In that case, the optimistic spinning code can get us into a situation where instead of going to sleep, A will spin waiting for B who is spinning waiting for A, and the only way out of that loop is the need_resched() test in mutex_spin_on_owner(). This patch fixes it by completely disabling spinning if we own the BKL. This adds one more detail to the extensive list of reasons why it's a bad idea for kernel code to be holding the BKL. Signed-off-by: Tony Breeds <tony@bakeyournoodle.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: <stable@kernel.org> LKML-Reference: <20100519054636.GC12389@ozlabs.org> [ added an unlikely() attribute to the branch ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-05-18Merge branch 'master' of /home/davem/src/GIT/linux-2.6/David S. Miller55-2275/+2862
Conflicts: include/linux/mod_devicetable.h scripts/mod/file2alias.c
2010-05-19padata: Use get_online_cpus/put_online_cpus in padata_freeSteffen Klassert1-0/+3
Add get_online_cpus/put_online_cpus to ensure that no cpu goes offline during the flushing of the padata percpu queues. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-05-19padata: Add some code commentsSteffen Klassert1-11/+57
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-05-19padata: Flush the padata queues activelySteffen Klassert1-8/+25
yield was used to wait until all references of the internal control structure in use are dropped before it is freed. This patch implements padata_flush_queues which actively flushes the padata percpu queues in this case. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-05-19padata: Use a timer to handle remaining objects in the reorder queues Steffen Klassert1-7/+18
padata_get_next needs to check whether the next object that need serialization must be parallel processed by the local cpu. This check was wrong implemented and returned always true, so the try_again loop in padata_reorder was never taken. This can lead to object leaks in some rare cases due to a race that appears with the trylock in padata_reorder. The try_again loop was not a good idea after all, because a cpu could take that loop frequently, so we handle this with a timer instead. This patch adds a timer to handle the race that appears with the trylock. If cpu1 queues an object to the reorder queue while cpu2 holds the pd->lock but left the while loop in padata_reorder already, cpu2 can't care for this object and cpu1 exits because it can't get the lock. Usually the next cpu that takes the lock cares for this object too. We need the timer just if this object was the last one that arrives to the reorder queues. The timer function sends it out in this case. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-05-18perf: Optimize perf_output_*() by avoiding local_xchg()Peter Zijlstra1-1/+2
Since the x86 XCHG ins implies LOCK, avoid the use by using a sequence count instead. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-05-18perf: Optimize the hotpath by converting the perf output buffer to local_tPeter Zijlstra1-15/+15
Since there is now only a single writer, we can use local_t instead and avoid all these pesky LOCK insn. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-05-18perf: Optimize the perf_output() path by removing IRQ-disablesPeter Zijlstra1-66/+28
Since we can now assume there is only a single writer to each buffer, we can remove per-cpu lock thingy and use a simply nest-count to the same effect. This removes the need to disable IRQs. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-05-18perf: Disallow mmap() on per-task inherited eventsPeter Zijlstra1-0/+8
Since we now have working per-task-per-cpu events for a while, disallow mmap() on per-task inherited events. Those things were a performance problem anyway, and doing away with it allows us to optimize the buffer somewhat by assuming there is only a single writer. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-05-18perf: Optimize buffer placement by allocating buffers NUMA awarePeter Zijlstra1-2/+15
Ensure cpu bound buffers live on the right NUMA node. Suggested-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1274114880.5605.5236.camel@twins> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-05-18perf: Fix errors path in perf_output_begin()Stephane Eranian1-1/+1
In case the sampling buffer has no "payload" pages, nr_pages is 0. The problem is that the error path in perf_output_begin() skips to a label which assumes perf_output_lock() has been issued which is not the case. That triggers a WARN_ON() in perf_output_unlock(). This patch fixes the problem by skipping perf_output_unlock() in case data->nr_pages is 0. Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <4bf13674.014fd80a.6c82.ffffb20c@mx.google.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-05-18perf/ftrace: Optimize perf/tracepoint interaction for single eventsPeter Zijlstra4-13/+23
When we've got but a single event per tracepoint there is no reason to try and multiplex it so don't. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Tested-by: Ingo Molnar <mingo@elte.hu> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-05-18Merge branch 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tipLinus Torvalds9-128/+551
* 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: tracing: Fix "integer as NULL pointer" warning. tracing: Fix tracepoint.h DECLARE_TRACE() to allow more than one header tracing: Make the documentation clear on trace_event boot option ring-buffer: Wrap open-coded WARN_ONCE tracing: Convert nop macros to static inlines tracing: Fix sleep time function profiling tracing: Show sample std dev in function profiling tracing: Add documentation for trace commands mod, traceon/traceoff ring-buffer: Make benchmark handle missed events ring-buffer: Make non-consuming read less expensive with lots of cpus. tracing: Add graph output support for irqsoff tracer tracing: Have graph flags passed in to ouput functions tracing: Add ftrace events for graph tracer tracing: Dump either the oops's cpu source or all cpus buffers tracing: Fix uninitialized variable of tracing/trace output
2010-05-18Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tipLinus Torvalds23-1046/+1001
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (49 commits) stop_machine: Move local variable closer to the usage site in cpu_stop_cpu_callback() sched, wait: Use wrapper functions sched: Remove a stale comment ondemand: Make the iowait-is-busy time a sysfs tunable ondemand: Solve a big performance issue by counting IOWAIT time as busy sched: Intoduce get_cpu_iowait_time_us() sched: Eliminate the ts->idle_lastupdate field sched: Fold updating of the last_update_time_info into update_ts_time_stats() sched: Update the idle statistics in get_cpu_idle_time_us() sched: Introduce a function to update the idle statistics sched: Add a comment to get_cpu_idle_time_us() cpu_stop: add dummy implementation for UP sched: Remove rq argument to the tracepoints rcu: need barrier() in UP synchronize_sched_expedited() sched: correctly place paranioa memory barriers in synchronize_sched_expedited() sched: kill paranoia check in synchronize_sched_expedited() sched: replace migration_thread with cpu_stop stop_machine: reimplement using cpu_stop cpu_stop: implement stop_cpu[s]() sched: Fix select_idle_sibling() logic in select_task_rq_fair() ...
2010-05-18Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tipLinus Torvalds16-902/+829
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (311 commits) perf tools: Add mode to build without newt support perf symbols: symbol inconsistency message should be done only at verbose=1 perf tui: Add explicit -lslang option perf options: Type check all the remaining OPT_ variants perf options: Type check OPT_BOOLEAN and fix the offenders perf options: Check v type in OPT_U?INTEGER perf options: Introduce OPT_UINTEGER perf tui: Add workaround for slang < 2.1.4 perf record: Fix bug mismatch with -c option definition perf options: Introduce OPT_U64 perf tui: Add help window to show key associations perf tui: Make <- exit menus too perf newt: Add single key shortcuts for zoom into DSO and threads perf newt: Exit browser unconditionally when CTRL+C, q or Q is pressed perf newt: Fix the 'A'/'a' shortcut for annotate perf newt: Make <- exit the ui_browser x86, perf: P4 PMU - fix counters management logic perf newt: Make <- zoom out filters perf report: Report number of events, not samples perf hist: Clarify events_stats fields usage ... Fix up trivial conflicts in kernel/fork.c and tools/perf/builtin-record.c
2010-05-18Merge branch 'oprofile-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tipLinus Torvalds6-22/+126
* 'oprofile-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (24 commits) oprofile/x86: make AMD IBS hotplug capable oprofile/x86: notify cpus only when daemon is running oprofile/x86: reordering some functions oprofile/x86: stop disabled counters in nmi handler oprofile/x86: protect cpu hotplug sections oprofile/x86: remove CONFIG_SMP macros oprofile/x86: fix uninitialized counter usage during cpu hotplug oprofile/x86: remove duplicate IBS capability check oprofile/x86: move IBS code oprofile/x86: return -EBUSY if counters are already reserved oprofile/x86: moving shutdown functions oprofile/x86: reserve counter msrs pairwise oprofile/x86: rework error handler in nmi_setup() oprofile: update file list in MAINTAINERS file oprofile: protect from not being in an IRQ context oprofile: remove double ring buffering ring-buffer: Add lost event count to end of sub buffer tracing: Show the lost events in the trace_pipe output ring-buffer: Add place holder recording of dropped events tracing: Fix compile error in module tracepoints when MODULE_UNLOAD not set ...
2010-05-18Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tipLinus Torvalds11-78/+230
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (24 commits) rcu: remove all rcu head initializations, except on_stack initializations rcu head introduce rcu head init on stack Debugobjects transition check rcu: fix build bug in RCU_FAST_NO_HZ builds rcu: RCU_FAST_NO_HZ must check RCU dyntick state rcu: make SRCU usable in modules rcu: improve the RCU CPU-stall warning documentation rcu: reduce the number of spurious RCU_SOFTIRQ invocations rcu: permit discontiguous cpu_possible_mask CPU numbering rcu: improve RCU CPU stall-warning messages rcu: print boot-time console messages if RCU configs out of ordinary rcu: disable CPU stall warnings upon panic rcu: enable CPU_STALL_VERBOSE by default rcu: slim down rcutiny by removing rcu_scheduler_active and friends rcu: refactor RCU's context-switch handling rcu: rename rcutiny rcu_ctrlblk to rcu_sched_ctrlblk rcu: shrink rcutiny by making synchronize_rcu_bh() be inline rcu: fix now-bogus rcu_scheduler_active comments. rcu: Fix bogus CONFIG_PROVE_LOCKING in comments to reflect reality. rcu: ignore offline CPUs in last non-dyntick-idle CPU check ...
2010-05-18Merge branch 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tipLinus Torvalds3-88/+123
* 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: lockdep: Reduce stack_trace usage lockdep: No need to disable preemption in debug atomic ops lockdep: Actually _dec_ in debug_atomic_dec lockdep: Provide off case for redundant_hardirqs_on increment lockdep: Simplify debug atomic ops lockdep: Fix redundant_hardirqs_on incremented with irqs enabled lockstat: Make lockstat counting per cpu i8253: Convert i8253_lock to raw_spinlock
2010-05-18[SCSI] Merge scsi-misc-2.6 into scsi-rc-fixes-2.6James Bottomley1-0/+16
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-05-18Merge branch 'perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip into trace/tip/tracing/core-6Steven Rostedt18-910/+849
Conflicts: include/trace/ftrace.h kernel/trace/trace_kprobe.c Acked-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-05-18Merge branch 'next' into for-linusJames Morris4-54/+5