The read of a proper MSR register was missed and instead of
counter the configration register was tested (it has
ARCH_P4_UNFLAGGED_BIT always cleared) leading to unknown NMI
hitting the system. As result the user may obtain "Dazed and
confused, but trying to continue" message. Fix it by reading a
proper MSR register.
When an NMI happens on a P4, the perf nmi handler checks the
configuration register to see if the overflow bit is set or not
before taking appropriate action. Unfortunately, various P4
machines had a broken overflow bit, so a backup mechanism was
implemented. This mechanism checked to see if the counter
rolled over or not.
A previous commit that implemented this backup mechanism was
broken. Instead of reading the counter register, it used the
configuration register to determine if the counter rolled over
or not. Reading that bit would give incorrect results.
This would lead to 'Dazed and confused' messages for the end
user when using the perf tool (or if the nmi watchdog is
running).
The fix is to read the counter register before determining if
the counter rolled over or not.
Signed-off-by: Don Zickus <dzickus@redhat.com> Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Lin Ming <ming.m.lin@intel.com>
LKML-Reference: <4D8BAB49.3080701@openvz.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
perf symbols: Look at .dynsym again if .symtab not found
The original intent of the code was to repeat the search with
want_symtab = 0. But as the code stands now, we never hit the "default"
case of the switch statement. Which means we never repeat the search.
Tested-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Reported-by: Arun Sharma <asharma@fb.com> Reported-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Dave Martin <dave.martin@linaro.org> 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>
"perf: 'perf kvm' tool for monitoring guest performance from host"
Added a field to struct build_id_event that broke the file format.
Since the kernel build-id is the first entry, process the table using
the old format if the well known '[kernel.kallsyms]' string for the
kernel build-id has the first 4 characters chopped off (where the pid_t
sits).
Reported-by: Han Pingtian <phan@redhat.com> Cc: Avi Kivity <avi@redhat.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> Cc: Zhang Yanmin <yanmin_zhang@linux.intel.com> Cc: stable@kernel.org
LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Resolving the sample->id to an evsel since the most advanced tools,
report and annotate, and the others will too when they evolve to
properly support multi-event perf.data files.
Good also because it does an extra validation, checking that the ID is
valid when present. When that is not the case, the overhead is just a
branch + function call (perf_evlist__id2evsel).
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>
perf: Better fit max unprivileged mlock pages for tools needs
The maximum kilobytes of locked memory that an unprivileged user
can reserve is of 512 kB = 128 pages by default, scaled to the
number of onlined CPUs, which fits well with the tools that use
128 data pages by default.
However tools actually use 129 pages, because they need one more
for the user control page. Thus the default mlock threshold is
not sufficient for the default tools needs and we always end up
to evaluate the constant mlock rlimit policy, which doesn't have
this scaling with the number of online CPUs.
Hence, on systems that have more than 16 CPUs, we overlap the
rlimit threshold and fail to mmap:
$ perf record ls
Error: failed to mmap with 1 (Operation not permitted)
Just increase the max unprivileged mlock threshold by one page
so that it supports well perf tools even after 16 CPUs.
Reported-by: Han Pingtian <phan@redhat.com> Reported-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Stephane Eranian <eranian@google.com> Cc: Stable <stable@kernel.org>
LKML-Reference: <1300904979-5508-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Stephane Eranian [Wed, 23 Mar 2011 15:03:06 +0000 (16:03 +0100)]
perf_events: Fix stale ->cgrp pointer in update_cgrp_time_from_cpuctx()
This patch solves a stale pointer problem in
update_cgrp_time_from_cpuctx(). The cpuctx->cgrp
was not cleared on all possible event exit paths,
including:
Jiri Olsa [Wed, 16 Feb 2011 16:35:34 +0000 (17:35 +0100)]
tracing: Fix set_ftrace_filter probe function display
If one or more function probes (like traceon) are enabled,
and there's no other function filter, the first probe
func is skipped (which one depends on the position in the hash).
The reason was, that in the case of no other function filter,
the func_pos was not properly updated before calling t_hash_start.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
LKML-Reference: <1297874134-7008-1-git-send-email-jolsa@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Stephane Eranian [Sat, 19 Mar 2011 17:20:05 +0000 (18:20 +0100)]
perf, x86: Fix Intel fixed counters base initialization
The following patch solves the problems introduced by Robert's
commit 41bf498 and reported by Arun Sharma. This commit gets rid
of the base + index notation for reading and writing PMU msrs.
The problem is that for fixed counters, the new calculation for
the base did not take into account the fixed counter indexes,
thus all fixed counters were read/written from fixed counter 0.
Although all fixed counters share the same config MSR, they each
have their own counter register.
Peter Zijlstra [Tue, 15 Mar 2011 13:37:10 +0000 (14:37 +0100)]
perf: Fix tear-down of inherited group events
When destroying inherited events, we need to destroy groups too,
otherwise the event iteration in perf_event_exit_task_context() will
miss group siblings and we leak events with all the consequences.
Richard Kennedy [Mon, 7 Mar 2011 15:46:59 +0000 (15:46 +0000)]
perf: Reorder & optimize perf_event_context to remove alignment padding on 64 bit builds
Remove 8 bytes of alignment padding from perf_event_context on 64 bit
builds which shrinks its size to 192 bytes allowing it to fit into one
fewer cache lines and into a smaller slab.
Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1299512819.2039.5.camel@castor.rsk> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Anton Blanchard [Wed, 9 Mar 2011 03:38:42 +0000 (14:38 +1100)]
perf, powerpc: Handle events that raise an exception without overflowing
Events on POWER7 can roll back if a speculative event doesn't
eventually complete. Unfortunately in some rare cases they will
raise a performance monitor exception. We need to catch this to
ensure we reset the PMC. In all cases the PMC will be 256 or less
cycles from overflow.
Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: <stable@kernel.org> # as far back as it applies cleanly
LKML-Reference: <20110309143842.6c22845e@kryten> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Lin Ming [Wed, 9 Mar 2011 15:21:29 +0000 (23:21 +0800)]
perf, x86: Use INTEL_*_CONSTRAINT() for all PEBS event constraints
PEBS_EVENT_CONSTRAINT() is just a duplicate of INTEL_UEVENT_CONSTRAINT().
Remove it and use INTEL_UEVENT_CONSTRAINT() instead.
Signed-off-by: Lin Ming <ming.m.lin@intel.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1299684089-22835-3-git-send-email-ming.m.lin@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Lin Ming [Wed, 9 Mar 2011 15:21:28 +0000 (23:21 +0800)]
perf, x86: Clean up SandyBridge PEBS events
Use INTEL_EVENT_CONSTRAINT() for the events where all umasks support PEBS.
Signed-off-by: Lin Ming <ming.m.lin@intel.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1299684089-22835-2-git-send-email-ming.m.lin@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Josh Hunt [Wed, 16 Mar 2011 02:16:40 +0000 (19:16 -0700)]
perf tools: Version incorrect with some versions of grep
Some versions of grep don't treat '\s' properly. When building perf on such
systems and using a kernel tarball the perf version is unable to be determined
from the main kernel Makefile and the user is left with a version of '..'.
Replacing the use of '\s' with '[[:space:]]', which should work in all grep
versions, gives a usable version number.
Linus Torvalds [Wed, 16 Mar 2011 03:01:36 +0000 (20:01 -0700)]
Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (27 commits)
x86: Clean up apic.c and apic.h
x86: Remove superflous goal definition of tsc_sync
x86: dt: Correct local apic documentation in device tree bindings
x86: dt: Cleanup local apic setup
x86: dt: Fix OLPC=y/INTEL_CE=n build
rtc: cmos: Add OF bindings
x86: ce4100: Use OF to setup devices
x86: ioapic: Add OF bindings for IO_APIC
x86: dtb: Add generic bus probe
x86: dtb: Add support for PCI devices backed by dtb nodes
x86: dtb: Add device tree support for HPET
x86: dtb: Add early parsing of IO_APIC
x86: dtb: Add irq domain abstraction
x86: dtb: Add a device tree for CE4100
x86: Add device tree support
x86: e820: Remove conditional early mapping in parse_e820_ext
x86: OLPC: Make OLPC=n build again
x86: OLPC: Remove extra OLPC_OPENFIRMWARE_DT indirection
x86: OLPC: Cleanup config maze completely
x86: OLPC: Hide OLPC_OPENFIRMWARE config switch
...
Fix up conflicts in arch/x86/platform/ce4100/ce4100.c
Linus Torvalds [Wed, 16 Mar 2011 02:49:10 +0000 (19:49 -0700)]
Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (93 commits)
x86, tlb, UV: Do small micro-optimization for native_flush_tlb_others()
x86-64, NUMA: Don't call numa_set_distanc() for all possible node combinations during emulation
x86-64, NUMA: Don't assume phys node 0 is always online in numa_emulation()
x86-64, NUMA: Clean up initmem_init()
x86-64, NUMA: Fix numa_emulation code with node0 without RAM
x86-64, NUMA: Revert NUMA affine page table allocation
x86: Work around old gas bug
x86-64, NUMA: Better explain numa_distance handling
x86-64, NUMA: Fix distance table handling
mm: Move early_node_map[] reverse scan helpers under HAVE_MEMBLOCK
x86-64, NUMA: Fix size of numa_distance array
x86: Rename e820_table_* to pgt_buf_*
bootmem: Move __alloc_memory_core_early() to nobootmem.c
bootmem: Move contig_page_data definition to bootmem.c/nobootmem.c
bootmem: Separate out CONFIG_NO_BOOTMEM code into nobootmem.c
x86-64, NUMA: Seperate out numa_alloc_distance() from numa_set_distance()
x86-64, NUMA: Add proper function comments to global functions
x86-64, NUMA: Move NUMA emulation into numa_emulation.c
x86-64, NUMA: Prepare numa_emulation() for moving NUMA emulation into a separate file
x86-64, NUMA: Do not scan two times for setup_node_bootmem()
...
Linus Torvalds [Wed, 16 Mar 2011 02:41:42 +0000 (19:41 -0700)]
Merge branch 'x86-mem-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-mem-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86-64, mem: Convert memmove() to assembly file and fix return value bug
Linus Torvalds [Wed, 16 Mar 2011 02:40:35 +0000 (19:40 -0700)]
Merge branch 'um-irq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'um-irq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
um: Select GENERIC_HARDIRQS_NO_DEPRECATED
um: Use proper accessors in show_interrupts()
um: Convert irq_chips to new functions
um: Remove stale irq_chip.end
Linus Torvalds [Wed, 16 Mar 2011 02:23:40 +0000 (19:23 -0700)]
Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (116 commits)
x86: Enable forced interrupt threading support
x86: Mark low level interrupts IRQF_NO_THREAD
x86: Use generic show_interrupts
x86: ioapic: Avoid redundant lookup of irq_cfg
x86: ioapic: Use new move_irq functions
x86: Use the proper accessors in fixup_irqs()
x86: ioapic: Use irq_data->state
x86: ioapic: Simplify irq chip and handler setup
x86: Cleanup the genirq name space
genirq: Add chip flag to force mask on suspend
genirq: Add desc->irq_data accessor
genirq: Add comments to Kconfig switches
genirq: Fixup fasteoi handler for oneshot mode
genirq: Provide forced interrupt threading
sched: Switch wait_task_inactive to schedule_hrtimeout()
genirq: Add IRQF_NO_THREAD
genirq: Allow shared oneshot interrupts
genirq: Prepare the handling of shared oneshot interrupts
genirq: Make warning in handle_percpu_event useful
x86: ioapic: Move trigger defines to io_apic.h
...
Fix up trivial(?) conflicts in arch/x86/pci/xen.c due to genirq name
space changes clashing with the Xen cleanups. The set_irq_msi() had
moved to xen_bind_pirq_msi_to_irq().
Linus Torvalds [Wed, 16 Mar 2011 02:16:00 +0000 (19:16 -0700)]
Merge branch 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: Combine printk()s in show_regs_common()
x86: Don't call dump_stack() from arch_trigger_all_cpu_backtrace_handler()
Linus Torvalds [Wed, 16 Mar 2011 02:00:53 +0000 (19:00 -0700)]
Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: Fix and clean up generic_processor_info()
x86: Don't copy per_cpu cpuinfo for BSP two times
x86: Move llc_shared_map out of cpu_info
Linus Torvalds [Wed, 16 Mar 2011 01:59:56 +0000 (18:59 -0700)]
Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, binutils, xen: Fix another wrong size directive
x86: Remove dead config option X86_CPU
x86: Really print supported CPUs if PROCESSOR_SELECT=y
x86: Fix a bogus unwind annotation in lib/semaphore_32.S
um, x86-64: Fix UML build after adding CFI annotations to lib/rwsem_64.S
x86: Remove unused bits from lib/thunk_*.S
x86: Use {push,pop}_cfi in more places
x86-64: Add CFI annotations to lib/rwsem_64.S
x86, asm: Cleanup unnecssary macros in asm-offsets.c
x86, system.h: Drop unused __SAVE/__RESTORE macros
x86: Use bitmap library functions
x86: Partly unify asm-offsets_{32,64}.c
x86: Reduce back the alignment of the per-CPU data section
Linus Torvalds [Wed, 16 Mar 2011 01:59:21 +0000 (18:59 -0700)]
Merge branch 'timers-rtc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-rtc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
RTC: Fix up rtc.txt documentation to reflect changes to generic rtc layer
RTC: sa1100: Update the sa1100 RTC driver.
RTC: Fix the cross interrupt issue on rtc-test.
RTC: Remove UIE and PIE information from the sa1100 driver proc.
RTC: Include information about UIE and PIE in RTC driver proc.
RTC: Clean out UIE icotl implementations
RTC: Cleanup rtc_class_ops->update_irq_enable()
RTC: Cleanup rtc_class_ops->irq_set_freq()
RTC: Cleanup rtc_class_ops->irq_set_state
RTC: Initialize kernel state from RTC
Linus Torvalds [Wed, 16 Mar 2011 01:53:35 +0000 (18:53 -0700)]
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (62 commits)
posix-clocks: Check write permissions in posix syscalls
hrtimer: Remove empty hrtimer_init_hres_timer()
hrtimer: Update hrtimer->state documentation
hrtimer: Update base[CLOCK_BOOTTIME].offset correctly
timers: Export CLOCK_BOOTTIME via the posix timers interface
timers: Add CLOCK_BOOTTIME hrtimer base
time: Extend get_xtime_and_monotonic_offset() to also return sleep
time: Introduce get_monotonic_boottime and ktime_get_boottime
hrtimers: extend hrtimer base code to handle more then 2 clockids
ntp: Remove redundant and incorrect parameter check
mn10300: Switch do_timer() to xtimer_update()
posix clocks: Introduce dynamic clocks
posix-timers: Cleanup namespace
posix-timers: Add support for fd based clocks
x86: Add clock_adjtime for x86
posix-timers: Introduce a syscall for clock tuning.
time: Splitout compat timex accessors
ntp: Add ADJ_SETOFFSET mode bit
time: Introduce timekeeping_inject_offset
posix-timer: Update comment
...
Fix up new system-call-related conflicts in
arch/x86/ia32/ia32entry.S
arch/x86/include/asm/unistd_32.h
arch/x86/include/asm/unistd_64.h
arch/x86/kernel/syscall_table_32.S
(name_to_handle_at()/open_by_handle_at() vs clock_adjtime()), and some
due to movement of get_jiffies_64() in:
kernel/time.c
Linus Torvalds [Wed, 16 Mar 2011 01:37:30 +0000 (18:37 -0700)]
Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (26 commits)
sched: Resched proper CPU on yield_to()
sched: Allow users with sufficient RLIMIT_NICE to change from SCHED_IDLE policy
sched: Allow SCHED_BATCH to preempt SCHED_IDLE tasks
sched: Clean up the IRQ_TIME_ACCOUNTING code
sched: Add #ifdef around irq time accounting functions
sched, autogroup: Stop claiming ownership of the root task group
sched, autogroup: Stop going ahead if autogroup is disabled
sched, autogroup, sysctl: Use proc_dointvec_minmax() instead
sched: Fix the group_imb logic
sched: Clean up some f_b_g() comments
sched: Clean up remnants of sd_idle
sched: Wholesale removal of sd_idle logic
sched: Add yield_to(task, preempt) functionality
sched: Use a buddy to implement yield_task_fair()
sched: Limit the scope of clear_buddies
sched: Check the right ->nr_running in yield_task_fair()
sched: Avoid expensive initial update_cfs_load(), on UP too
sched: Fix switch_from_fair()
sched: Simplify the idle scheduling class
softirqs: Account ksoftirqd time as cpustat softirq
...
Linus Torvalds [Wed, 16 Mar 2011 01:31:30 +0000 (18:31 -0700)]
Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (184 commits)
perf probe: Clean up probe_point_lazy_walker() return value
tracing: Fix irqoff selftest expanding max buffer
tracing: Align 4 byte ints together in struct tracer
tracing: Export trace_set_clr_event()
tracing: Explain about unstable clock on resume with ring buffer warning
ftrace/graph: Trace function entry before updating index
ftrace: Add .ref.text as one of the safe areas to trace
tracing: Adjust conditional expression latency formatting.
tracing: Fix event alignment: skb:kfree_skb
tracing: Fix event alignment: mce:mce_record
tracing: Fix event alignment: kvm:kvm_hv_hypercall
tracing: Fix event alignment: module:module_request
tracing: Fix event alignment: ftrace:context_switch and ftrace:wakeup
tracing: Remove lock_depth from event entry
perf header: Stop using 'self'
perf session: Use evlist/evsel for managing perf.data attributes
perf top: Don't let events to eat up whole header line
perf top: Fix events overflow in top command
ring-buffer: Remove unused #include <linux/trace_irq.h>
tracing: Add an 'overwrite' trace_option.
...
Linus Torvalds [Wed, 16 Mar 2011 01:23:52 +0000 (18:23 -0700)]
Merge branch 'core-futexes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-futexes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
arm: Remove bogus comment in futex_atomic_cmpxchg_inatomic()
futex: Deobfuscate handle_futex_death()
plist: Add priority list test
plist: Shrink struct plist_head
futex,plist: Remove debug lock assignment from plist_node
futex,plist: Pass the real head of the priority list to plist_del()
futex: Sanitize futex ops argument types
futex: Sanitize cmpxchg_futex_value_locked API
futex: Remove redundant pagefault_disable in futex_atomic_cmpxchg_inatomic()
futex: Avoid redudant evaluation of task_pid_vnr()
futex: Update futex_wait_setup comments about locking
Linus Torvalds [Wed, 16 Mar 2011 01:23:25 +0000 (18:23 -0700)]
Merge branch 'core-debugobjects-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-debugobjects-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
debugobjects: Add hint for better object identification
Linus Torvalds [Tue, 15 Mar 2011 22:48:13 +0000 (15:48 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (57 commits)
tidy the trailing symlinks traversal up
Turn resolution of trailing symlinks iterative everywhere
simplify link_path_walk() tail
Make trailing symlink resolution in path_lookupat() iterative
update nd->inode in __do_follow_link() instead of after do_follow_link()
pull handling of one pathname component into a helper
fs: allow AT_EMPTY_PATH in linkat(), limit that to CAP_DAC_READ_SEARCH
Allow passing O_PATH descriptors via SCM_RIGHTS datagrams
readlinkat(), fchownat() and fstatat() with empty relative pathnames
Allow O_PATH for symlinks
New kind of open files - "location only".
ext4: Copy fs UUID to superblock
ext3: Copy fs UUID to superblock.
vfs: Export file system uuid via /proc/<pid>/mountinfo
unistd.h: Add new syscalls numbers to asm-generic
x86: Add new syscalls for x86_64
x86: Add new syscalls for x86_32
fs: Remove i_nlink check from file system link callback
fs: Don't allow to create hardlink for deleted file
vfs: Add open by file handle support
...
Trond Myklebust [Tue, 15 Mar 2011 17:36:43 +0000 (13:36 -0400)]
VFS: Fix the nfs sillyrename regression in kernel 2.6.38
The new vfs locking scheme introduced in 2.6.38 breaks NFS sillyrename
because the latter relies on being able to determine the parent
directory of the dentry in the ->iput() callback in order to send the
appropriate unlink rpc call.
Looking at the code that cares about races with dput(), there doesn't
seem to be anything that specifically uses d_parent as a test for
whether or not there is a race:
- __d_lookup_rcu(), __d_lookup() all test for d_hashed() after d_parent
- shrink_dcache_for_umount() is safe since nothing else can rearrange
the dentries in that super block.
- have_submount(), select_parent() and d_genocide() can test for a
deletion if we set the DCACHE_DISCONNECTED flag when the dentry
is removed from the parent's d_subdirs list.
Linus Torvalds [Tue, 15 Mar 2011 22:29:21 +0000 (15:29 -0700)]
dcache.c: create helper function for duplicated functionality
This creates a helper function for he "try to ascend into the parent
directory" case, which was written out in triplicate before. With all
the locking and subtle sequence number stuff, we really don't want to
duplicate that kind of code.
Al Viro [Tue, 15 Mar 2011 02:20:34 +0000 (22:20 -0400)]
tidy the trailing symlinks traversal up
* pull the handling of current->total_link_count into
__do_follow_link()
* put the common "do ->put_link() if needed and path_put() the link"
stuff into a helper (put_link(nd, link, cookie))
* rename __do_follow_link() to follow_link(), while we are at it
Al Viro [Tue, 15 Mar 2011 01:54:55 +0000 (21:54 -0400)]
Turn resolution of trailing symlinks iterative everywhere
The last remaining place (resolution of nested symlink) converted
to the loop of the same kind we have in path_lookupat() and
path_openat().
Note that we still *do* have a recursion in pathname resolution;
can't avoid it, really. However, it's strictly for nested symlinks
now - i.e. ones in the middle of a pathname.
link_path_walk() has lost the tail now - it always walks everything
except the last component.
do_follow_link() renamed to nested_symlink() and moved down.
Al Viro [Tue, 15 Mar 2011 01:28:04 +0000 (21:28 -0400)]
simplify link_path_walk() tail
Now that link_path_walk() is called without LOOKUP_PARENT
only from do_follow_link(), we can simplify the checks in
last component handling. First of all, checking if we'd
arrived to a directory is not needed - the caller will check
it anyway. And LOOKUP_FOLLOW is guaranteed to be there,
since we only get to that place with nd->depth > 0.
Al Viro [Sun, 13 Mar 2011 23:58:58 +0000 (19:58 -0400)]
pull handling of one pathname component into a helper
new helper: walk_component(). Handles everything except symlinks;
returns negative on error, 0 on success and 1 on symlinks we decided
to follow. Drops out of RCU mode on such symlinks.
link_path_walk() and do_last() switched to using that.
fs: allow AT_EMPTY_PATH in linkat(), limit that to CAP_DAC_READ_SEARCH
We don't want to allow creation of private hardlinks by different application
using the fd passed to them via SCM_RIGHTS. So limit the null relative name
usage in linkat syscall to CAP_DAC_READ_SEARCH
Ingo Molnar [Tue, 15 Mar 2011 19:51:09 +0000 (20:51 +0100)]
perf probe: Clean up probe_point_lazy_walker() return value
Newer compilers (gcc 4.6) complains about:
return ret < 0 ?: 0;
For the following reason:
util/probe-finder.c: In function ‘probe_point_lazy_walker’:
util/probe-finder.c:1331:18: error: the omitted middle operand in ?: will always be ‘true’, suggest explicit middle operand [-Werror=parentheses]
And indeed the return value is a somewhat obscure (but correct) value
of 'true', so return 'ret' instead - this is cleaner and unconfuses
GCC as well.
Linus Torvalds [Tue, 15 Mar 2011 17:59:09 +0000 (10:59 -0700)]
Merge branch 'for-linus' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm
* 'for-linus' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm:
xen: suspend: remove xen_hvm_suspend
xen: suspend: pull pre/post suspend hooks out into suspend_info
xen: suspend: move arch specific pre/post suspend hooks into generic hooks
xen: suspend: refactor non-arch specific pre/post suspend hooks
xen: suspend: add "arch" to pre/post suspend hooks
xen: suspend: pass extra hypercall argument via suspend_info struct
xen: suspend: refactor cancellation flag into a structure
xen: suspend: use HYPERVISOR_suspend for PVHVM case instead of open coding
xen: switch to new schedop hypercall by default.
xen: use new schedop interface for suspend
xen: do not respond to unknown xenstore control requests
xen: fix compile issue if XEN is enabled but XEN_PVHVM is disabled
xen: PV on HVM: support PV spinlocks and IPIs
xen: make the ballon driver work for hvm domains
xen-blkfront: handle Xen major numbers other than XENVBD
xen: do not use xen_info on HVM, set pv_info name to "Xen HVM"
xen: no need to delay xen_setup_shutdown_event for hvm guests anymore
Linus Torvalds [Tue, 15 Mar 2011 17:49:16 +0000 (10:49 -0700)]
Merge branches 'stable/ia64', 'stable/blkfront-cleanup' and 'stable/cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/ia64' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen: ia64 build broken due to "xen: switch to new schedop hypercall by default."
* 'stable/blkfront-cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen: Union the blkif_request request specific fields
* 'stable/cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen: annotate functions which only call into __init at start of day
xen p2m: annotate variable which appears unused
xen: events: mark cpu_evtchn_mask_p as __refdata
Linus Torvalds [Tue, 15 Mar 2011 17:47:56 +0000 (10:47 -0700)]
Merge branch 'stable/irq.cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/irq.cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen: events: remove dom0 specific xen_create_msi_irq
xen: events: use xen_bind_pirq_msi_to_irq from xen_create_msi_irq
xen: events: push set_irq_msi down into xen_create_msi_irq
xen: events: update pirq_to_irq in xen_create_msi_irq
xen: events: refactor xen_create_msi_irq slightly
xen: events: separate MSI PIRQ allocation from PIRQ binding to IRQ
xen: events: assume PHYSDEVOP_get_free_pirq exists
xen: pci: collapse apic_register_gsi_xen_hvm and xen_hvm_register_pirq
xen: events: return irq from xen_allocate_pirq_msi
xen: events: drop XEN_ALLOC_IRQ flag to xen_allocate_pirq_msi
xen: events: do not leak IRQ from xen_allocate_pirq_msi when no pirq available.
xen: pci: only define xen_initdom_setup_msi_irqs if CONFIG_XEN_DOM0
Linus Torvalds [Tue, 15 Mar 2011 17:47:16 +0000 (10:47 -0700)]
Merge branches 'stable/irq.rework' and 'stable/pcifront-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/irq.rework' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/irq: Cleanup up the pirq_to_irq for DomU PV PCI passthrough guests as well.
xen: Use IRQF_FORCE_RESUME
xen/timer: Missing IRQF_NO_SUSPEND in timer code broke suspend.
xen: Fix compile error introduced by "switch to new irq_chip functions"
xen: Switch to new irq_chip functions
xen: Remove stale irq_chip.end
xen: events: do not free legacy IRQs
xen: events: allocate GSIs and dynamic IRQs from separate IRQ ranges.
xen: events: add xen_allocate_irq_{dynamic, gsi} and xen_free_irq
xen:events: move find_unbound_irq inside CONFIG_PCI_MSI
xen: handled remapped IRQs when enabling a pcifront PCI device.
genirq: Add IRQF_FORCE_RESUME
* 'stable/pcifront-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
pci/xen: When free-ing MSI-X/MSI irq->desc also use generic code.
pci/xen: Cleanup: convert int** to int[]
pci/xen: Use xen_allocate_pirq_msi instead of xen_allocate_pirq
xen-pcifront: Sanity check the MSI/MSI-X values
xen-pcifront: don't use flush_scheduled_work()
Linus Torvalds [Tue, 15 Mar 2011 17:32:15 +0000 (10:32 -0700)]
Merge branches 'stable/p2m-identity.v4.9.1' and 'stable/e820' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/p2m-identity.v4.9.1' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/m2p: Check whether the MFN has IDENTITY_FRAME bit set..
xen/m2p: No need to catch exceptions when we know that there is no RAM
xen/debug: WARN_ON when identity PFN has no _PAGE_IOMAP flag set.
xen/debugfs: Add 'p2m' file for printing out the P2M layout.
xen/setup: Set identity mapping for non-RAM E820 and E820 gaps.
xen/mmu: WARN_ON when racing to swap middle leaf.
xen/mmu: Set _PAGE_IOMAP if PFN is an identity PFN.
xen/mmu: Add the notion of identity (1-1) mapping.
xen: Mark all initial reserved pages for the balloon as INVALID_P2M_ENTRY.
* 'stable/e820' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/e820: Don't mark balloon memory as E820_UNUSABLE when running as guest and fix overflow.
xen/setup: Inhibit resource API from using System RAM E820 gaps as PCI mem gaps.
Al Viro [Sun, 13 Mar 2011 19:56:26 +0000 (15:56 -0400)]
readlinkat(), fchownat() and fstatat() with empty relative pathnames
For readlinkat() we simply allow empty pathname; it will fail unless
we have dfd equal to O_PATH-opened symlink, so we are outside of
POSIX scope here. For fchownat() and fstatat() we allow AT_EMPTY_PATH;
let the caller explicitly ask for such behaviour.
Al Viro [Sun, 13 Mar 2011 20:42:14 +0000 (16:42 -0400)]
Allow O_PATH for symlinks
At that point we can't do almost nothing with them. They can be opened
with O_PATH, we can manipulate such descriptors with dup(), etc. and
we can see them in /proc/*/{fd,fdinfo}/*.
We can't (and won't be able to) follow /proc/*/fd/* symlinks for those;
there's simply not enough information for pathname resolution to go on
from such point - to resolve a symlink we need to know which directory
does it live in.
We will be able to do useful things with them after the next commit, though -
readlinkat() and fchownat() will be possible to use with dfd being an
O_PATH-opened symlink and empty relative pathname. Combined with
open_by_handle() it'll give us a way to do realink-by-handle and
lchown-by-handle without messing with more redundant syscalls.
Al Viro [Sun, 13 Mar 2011 07:51:11 +0000 (03:51 -0400)]
New kind of open files - "location only".
New flag for open(2) - O_PATH. Semantics:
* pathname is resolved, but the file itself is _NOT_ opened
as far as filesystem is concerned.
* almost all operations on the resulting descriptors shall
fail with -EBADF. Exceptions are:
1) operations on descriptors themselves (i.e.
close(), dup(), dup2(), dup3(), fcntl(fd, F_DUPFD),
fcntl(fd, F_DUPFD_CLOEXEC, ...), fcntl(fd, F_GETFD),
fcntl(fd, F_SETFD, ...))
2) fcntl(fd, F_GETFL), for a common non-destructive way to
check if descriptor is open
3) "dfd" arguments of ...at(2) syscalls, i.e. the starting
points of pathname resolution
* closing such descriptor does *NOT* affect dnotify or
posix locks.
* permissions are checked as usual along the way to file;
no permission checks are applied to the file itself. Of course,
giving such thing to syscall will result in permission checks (at
the moment it means checking that starting point of ....at() is
a directory and caller has exec permissions on it).
fget() and fget_light() return NULL on such descriptors; use of
fget_raw() and fget_raw_light() is needed to get them. That protects
existing code from dealing with those things.
There are two things still missing (they come in the next commits):
one is handling of symlinks (right now we refuse to open them that
way; see the next commit for semantics related to those) and another
is descriptor passing via SCM_RIGHTS datagrams.
fs: Don't allow to create hardlink for deleted file
Add inode->i_nlink == 0 check in VFS. Some of the file systems
do this internally. A followup patch will remove those instance.
This is needed to ensure that with link by handle we don't allow
to create hardlink of an unlinked file. The check also prevent a race
between unlink and link
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Al Viro [Mon, 14 Mar 2011 22:56:51 +0000 (18:56 -0400)]
New AT_... flag: AT_EMPTY_PATH
For name_to_handle_at(2) we'll want both ...at()-style syscall that
would be usable for non-directory descriptors (with empty relative
pathname). Introduce new flag (AT_EMPTY_PATH) to deal with that and
corresponding LOOKUP_EMPTY; teach user_path_at() and path_init() to
deal with the latter.
Linus Torvalds [Mon, 14 Mar 2011 22:20:39 +0000 (15:20 -0700)]
Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-mn10300
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-mn10300:
MN10300: atomic_read() should ensure it emits a load
MN10300: The SMP_ICACHE_INV_FLUSH_RANGE IPI command does not exist
MN10300: Proper use of macros get_user() in the case of incremented pointers
Linus Torvalds [Mon, 14 Mar 2011 22:20:12 +0000 (15:20 -0700)]
Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/upstream-linus
* 'upstream' of git://git.linux-mips.org/pub/scm/upstream-linus: (26 commits)
MIPS: Alchemy: Fix reset for MTX-1 and XXS1500
MIPS: MTX-1: Make au1000_eth probe all PHY addresses
MIPS: Jz4740: Add HAVE_CLK
MIPS: Move idle task creation to work queue
MIPS, Perf-events: Use unsigned delta for right shift in event update
MIPS, Perf-events: Work with the new callchain interface
MIPS, Perf-events: Fix event check in validate_event()
MIPS, Perf-events: Work with the new PMU interface
MIPS, Perf-events: Work with irq_work
MIPS: Fix always CONFIG_LOONGSON_UART_BASE=y
MIPS: Loongson: Fix potentially wrong string handling
MIPS: Fix GCC-4.6 'set but not used' warning in arch/mips/mm/init.c
MIPS: Fix GCC-4.6 'set but not used' warning in ieee754int.h
MIPS: Remove unused code from arch/mips/kernel/syscall.c
MIPS: Fix GCC-4.6 'set but not used' warning in signal*.c
MIPS: MSP: Fix MSP71xx bpci interrupt handler return value
MIPS: Select R4K timer lib for all MSP platforms
MIPS: Loongson: Remove ad-hoc cmdline default
MIPS: Clear the correct flag in sysmips(MIPS_FIXADE, ...).
MIPS: Add an unreachable return statement to satisfy buggy GCCs.
...
Linus Torvalds [Mon, 14 Mar 2011 22:19:09 +0000 (15:19 -0700)]
Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: ce4100: Set pci ops via callback instead of module init
x86/mm: Fix pgd_lock deadlock
x86/mm: Handle mm_fault_error() in kernel space
x86: Don't check for BIOS corruption in first 64K when there's no need to
Linus Torvalds [Mon, 14 Mar 2011 22:17:07 +0000 (15:17 -0700)]
Revert "oom: oom_kill_process: fix the child_points logic"
This reverts the parent commit. I hate doing that, but it's generating
some discussion ("half of it is right"), and since I am planning on
doing the 2.6.38 release later today we can punt it to stable if
required. Let's not rock the boat right now.
Oleg Nesterov [Mon, 14 Mar 2011 19:05:30 +0000 (20:05 +0100)]
oom: oom_kill_process: fix the child_points logic
oom_kill_process() starts with victim_points == 0. This means that
(most likely) any child has more points and can be killed erroneously.
Also, "children has a different mm" doesn't match the reality, we should
check child->mm != t->mm. This check is not exactly correct if t->mm ==
NULL but this doesn't really matter, oom_kill_task() will kill them
anyway.
Note: "Kill all processes sharing p->mm" in oom_kill_task() is wrong
too.
Thomas Gleixner [Mon, 14 Mar 2011 19:00:30 +0000 (20:00 +0100)]
arm: Remove bogus comment in futex_atomic_cmpxchg_inatomic()
commit 522d7dec(futex: Remove redundant pagefault_disable in
futex_atomic_cmpxchg_inatomic()) added a bogus comment.
/* Note that preemption is disabled by futex_atomic_cmpxchg_inatomic
* call sites. */
Bogus in two aspects:
1) pagefault_disable != preempt_disable even if the mechanism we use
is the same
2) we have a call site which deliberately does not disable pagefaults
as it wants the possible fault to be handled - though that has been
changed for consistency reasons now.
Sigh. I really should have seen that when committing the above. :(
Catched-by-and-rightfully-ranted-at-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <alpine.LFD.2.00.1103141126590.2787@localhost6.localdomain6> Cc: Michel Lespinasse <walken@google.com> Cc: Darren Hart <darren@dvhart.com>
Thomas Gleixner [Mon, 14 Mar 2011 09:34:35 +0000 (10:34 +0100)]
futex: Deobfuscate handle_futex_death()
handle_futex_death() uses futex_atomic_cmpxchg_inatomic() without
disabling page faults. That's ok, but totally non obvious.
We don't hold locks so we actually can and want to fault here, because
the get_user() before futex_atomic_cmpxchg_inatomic() does not
guarantee a R/W mapping.
We could just add a big fat comment to explain this, but actually
changing the code so that the functionality is entirely clear is
better.
Use the helper function which disables page faults around the
futex_atomic_cmpxchg_inatomic() and handle a fault with a call to
fault_in_user_writeable() as all other places in the futex code do as
well.
Pointed-out-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Darren Hart <darren@dvhart.com> Cc: Michel Lespinasse <walken@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: David Howells <dhowells@redhat.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Chris Metcalf <cmetcalf@tilera.com>
LKML-Reference: <alpine.LFD.2.00.1103141126590.2787@localhost6.localdomain6> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Florian Fainelli [Mon, 21 Feb 2011 13:28:02 +0000 (14:28 +0100)]
MIPS: Alchemy: Fix reset for MTX-1 and XXS1500
Since commit 32fd6901 (MIPS: Alchemy: get rid of common/reset.c)
Alchemy-based boards use their own reset function. For MTX-1 and XXS1500,
the reset function pokes at the BCSR.SYSTEM_RESET register, but this does
not work. According to Bruno Randolf, this was not tested when written.
Previously, the generic au1000_restart() routine called the board specific
reset function, which for MTX-1 and XXS1500 did not work, but finally made
a jump to the reset vector, which really triggers a system restart. Fix
reboot for both targets by jumping to the reset vector.
Signed-off-by: Florian Fainelli <florian@openwrt.org>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2093/ Acked-by: Bruno Randolf <br1@einfach.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Florian Fainelli [Sun, 27 Feb 2011 18:53:53 +0000 (19:53 +0100)]
MIPS: MTX-1: Make au1000_eth probe all PHY addresses
When au1000_eth probes the MII bus for PHY address, if we do not set
au1000_eth platform data's phy_search_highest_address, the MII probing
logic will exit early and will assume a valid PHY is found at address 0.
For MTX-1, the PHY is at address 31, and without this patch, the link
detection/speed/duplex would not work correctly.
Maksim Rayskiy [Sat, 12 Feb 2011 18:21:32 +0000 (10:21 -0800)]
MIPS: Move idle task creation to work queue
To avoid forking usermode thread when creating an idle task, move fork_idle
to a work queue.
If kernel starts with maxcpus= option which does not bring all available
cpus online at boot time, idle tasks for offline cpus are not created. If
later offline cpus are hotplugged through sysfs, __cpu_up is called in
the context of the user task, and fork_idle copies its non-zero mm
pointer. This causes BUG() in per_cpu_trap_init.
This also avoids issues with resource limits of the CPU writing to sysfs,
containers, maybe others.
Signed-off-by: Maksim Rayskiy <mrayskiy@broadcom.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2070/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Hardware performance counters on ARM are 32-bits wide but atomic64_t
variables are used to represent counter data in the hw_perf_event structure.
The armpmu_event_update function right-shifts a signed 64-bit delta variable
and adds the result to the event count. This can lead to shifting in sign-bits
if the MSB of the 32-bit counter value is set. This results in perf output
such as:
- Most archs use one callchain buffer per cpu, except x86 that needs
to deal with NMIs. Provide a default perf_callchain_buffer()
implementation that x86 overrides.
- Centralize all the kernel/user regs handling and invoke new arch
handlers from there: perf_callchain_user() / perf_callchain_kernel()
That avoid all the user_mode(), current->mm checks and so...
- Invert some parameters in perf_callchain_*() helpers: entry to the
left, regs to the right, following the traditional (dst, src).
Drop the TASK_RUNNING test on user tasks for callchains as
this check doesn't seem to make any sense.
Also remove the tests for !current that is not supposed to
happen and current->pid as this should be handled at the
generic level, with exclude_idle attribute.
The validate_event function in the ARM perf events backend has the
following problems:
1.) Events that are disabled count towards the cost.
2.) Events associated with other PMUs [for example, software events or
breakpoints] do not count towards the cost, but do fail validation,
causing the group to fail.
This patch changes validate_event so that it ignores events in the
PERF_EVENT_STATE_OFF state or that are scheduled for other PMUs.
Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: David Daney <ddaney@caviumnetworks.com> Signed-off-by: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
To: a.p.zijlstra@chello.nl
To: fweisbec@gmail.com
To: will.deacon@arm.com Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Cc: wuzhangjin@gmail.com Cc: paulus@samba.org Cc: mingo@elte.hu Cc: acme@redhat.com Cc: dengcheng.zhu@gmail.com Cc: matt@console-pimps.org Cc: sshtylyov@mvista.com Cc: ddaney@caviumnetworks.com
Patchwork: http://patchwork.linux-mips.org/patch/2013/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Replace pmu::{enable,disable,start,stop,unthrottle} with
pmu::{add,del,start,stop}, all of which take a flags argument.
The new interface extends the capability to stop a counter while
keeping it scheduled on the PMU. We replace the throttled state with
the generic stopped state.
This also allows us to efficiently stop/start counters over certain
code paths (like IRQ handlers).
It also allows scheduling a counter without it starting, allowing for
a generic frozen state (useful for rotating stopped counters).
The stopped state is implemented in two different ways, depending on
how the architecture implemented the throttled state:
1) We disable the counter:
a) the pmu has per-counter enable bits, we flip that
b) we program a NOP event, preserving the counter state
2) We store the counter state and ignore all read/overflow events
For MIPSXX, the stopped state is implemented in the way of 1.b as above.
Provide a mechanism that allows running code in IRQ context. It is
most useful for NMI code that needs to interact with the rest of the
system -- like wakeup a task to drain buffers.
Perf currently has such a mechanism, so extract that and provide it as
a generic feature, independent of perf so that others may also
benefit.
The IRQ context callback is generated through self-IPIs where
possible, or on architectures like powerpc the decrementer (the
built-in timer facility) is set to generate an interrupt immediately.
Architectures that don't have anything like this get to do with a
callback from the timer tick. These architectures can call
irq_work_run() at the tail of any IRQ handlers that might enqueue such
work (like the perf IRQ handler) to avoid undue latencies in
processing the work.
For MIPSXX, we need to call irq_work_run() at the tail of the perf IRQ
handler as described above.
Reported-by: Wu Zhangjin <wuzhangjin@gmail.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: David Daney <ddaney@caviumnetworks.com> Signed-off-by: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
To: fweisbec@gmail.com
To: will.deacon@arm.com Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Cc: paulus@samba.org Cc: mingo@elte.hu Cc: acme@redhat.com Cc: matt@console-pimps.org Cc: sshtylyov@mvista.com,
Patchwork: http://patchwork.linux-mips.org/patch/2011/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
David Daney [Mon, 24 Jan 2011 22:51:36 +0000 (14:51 -0800)]
MIPS: Fix GCC-4.6 'set but not used' warning in ieee754int.h
GCC-4.6 can find more unused code than previous versions could.
In the case of arch/mips/math-emu/ieee754int.h, the COMPXSP and
COMPXDP macros are used in several places, but a couple of them leave
xs unused. The easiest thing to do is mark it as __maybe_unused to
quiet the warning.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2032/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
David Daney [Mon, 24 Jan 2011 22:51:34 +0000 (14:51 -0800)]
MIPS: Fix GCC-4.6 'set but not used' warning in signal*.c
GCC-4.6 can find more unused code than previous versions could.
In the case of protected_restore_fp_context{,32}, the variable tmp is
really used. Its use is tricky in that we really care about the side
effects of the __put_user() calls. So we must mark tmp with
__maybe_unused to quiet the warning.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2035/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Anoop P A [Thu, 18 Nov 2010 10:32:50 +0000 (16:02 +0530)]
MIPS: MSP: Fix MSP71xx bpci interrupt handler return value
Signed-off-by: Anoop P A <anoop.pa@gmail.com>
To: Ben Hutchings <ben@decadent.org.uk>
To: linux-mips@linux-mips.org
To: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/1804/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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