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2009-12-19Merge branch 'timers-fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: timers: Remove duplicate setting of new_base in __mod_timer() clockevents: Prevent clockevent_devices list corruption on cpu hotplug
2009-12-19fix more leaks in audit_tree.c tag_chunk()Al Viro
Several leaks in audit_tree didn't get caught by commit 318b6d3d7ddbcad3d6867e630711b8a705d873d7, including the leak on normal exit in case of multiple rules refering to the same chunk. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-19fix braindamage in audit_tree.c untag_chunk()Al Viro
... aka "Al had badly fscked up when writing that thing and nobody noticed until Eric had fixed leaks that used to mask the breakage". The function essentially creates a copy of old array sans one element and replaces the references to elements of original (they are on cyclic lists) with those to corresponding elements of new one. After that the old one is fair game for freeing. First of all, there's a dumb braino: when we get to list_replace_init we use indices for wrong arrays - position in new one with the old array and vice versa. Another bug is more subtle - termination condition is wrong if the element to be excluded happens to be the last one. We shouldn't go until we fill the new array, we should go until we'd finished the old one. Otherwise the element we are trying to kill will remain on the cyclic lists... That crap used to be masked by several leaks, so it was not quite trivial to hit. Eric had fixed some of those leaks a while ago and the shit had hit the fan... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-17Merge branch 'cpumask-cleanups' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus * 'cpumask-cleanups' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus: cpumask: rename tsk_cpumask to tsk_cpus_allowed cpumask: don't recommend set_cpus_allowed hack in Documentation/cpu-hotplug.txt cpumask: avoid dereferencing struct cpumask cpumask: convert drivers/idle/i7300_idle.c to cpumask_var_t cpumask: use modern cpumask style in drivers/scsi/fcoe/fcoe.c cpumask: avoid deprecated function in mm/slab.c cpumask: use cpu_online in kernel/perf_event.c
2009-12-17Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6: Keys: KEYCTL_SESSION_TO_PARENT needs TIF_NOTIFY_RESUME architecture support NOMMU: Optimise away the {dac_,}mmap_min_addr tests security/min_addr.c: make init_mmap_min_addr() static keys: PTR_ERR return of wrong pointer in keyctl_get_security()
2009-12-17Merge branch 'kmemleak' of git://linux-arm.org/linux-2.6Linus Torvalds
* 'kmemleak' of git://linux-arm.org/linux-2.6: kmemleak: fix kconfig for crc32 build error kmemleak: Reduce the false positives by checking for modified objects kmemleak: Show the age of an unreferenced object kmemleak: Release the object lock before calling put_object() kmemleak: Scan the _ftrace_events section in modules kmemleak: Simplify the kmemleak_scan_area() function prototype kmemleak: Do not use off-slab management with SLAB_NOLEAKTRACE
2009-12-17printk: fix new kernel-doc warningsRandy Dunlap
Fix kernel-doc warnings in printk.c: Warning(kernel/printk.c:1422): No description found for parameter 'dumper' Warning(kernel/printk.c:1422): Excess function parameter 'dump' description in 'kmsg_dump_register' Warning(kernel/printk.c:1451): No description found for parameter 'dumper' Warning(kernel/printk.c:1451): Excess function parameter 'dump' description in 'kmsg_dump_unregister' Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-17do_wait() optimization: do not place sub-threads on task_struct->children listOleg Nesterov
Thanks to Roland who pointed out de_thread() issues. Currently we add sub-threads to ->real_parent->children list. This buys nothing but slows down do_wait(). With this patch ->children contains only main threads (group leaders). The only complication is that forget_original_parent() should iterate over sub-threads by hand, and de_thread() needs another list_replace() when it changes ->group_leader. Henceforth do_wait_thread() can never see task_detached() && !EXIT_DEAD tasks, we can remove this check (and we can unify do_wait_thread() and ptrace_do_wait()). This change can confuse the optimistic search in mm_update_next_owner(), but this is fixable and minor. Perhaps badness() and oom_kill_process() should be updated, but they should be fixed in any case. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: Roland McGrath <roland@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Ratan Nalumasu <rnalumasu@gmail.com> Cc: Vitaly Mayatskikh <vmayatsk@redhat.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-17kernel/sysctl.c: fix the incomplete part of ↵WANG Cong
sysctl_max_map_count-should-be-non-negative.patch It is a mistake that we used 'proc_dointvec', it should be 'proc_dointvec_minmax', as in the original patch. Signed-off-by: WANG Cong <amwang@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-17Merge branch 'for-33' of git://repo.or.cz/linux-kbuildLinus Torvalds
* 'for-33' of git://repo.or.cz/linux-kbuild: (29 commits) net: fix for utsrelease.h moving to generated gen_init_cpio: fixed fwrite warning kbuild: fix make clean after mismerge kbuild: generate modules.builtin genksyms: properly consider EXPORT_UNUSED_SYMBOL{,_GPL}() score: add asm/asm-offsets.h wrapper unifdef: update to upstream revision 1.190 kbuild: specify absolute paths for cscope kbuild: create include/generated in silentoldconfig scripts/package: deb-pkg: use fakeroot if available scripts/package: add KBUILD_PKG_ROOTCMD variable scripts/package: tar-pkg: use tar --owner=root Kbuild: clean up marker net: add net_tstamp.h to headers_install kbuild: move utsrelease.h to include/generated kbuild: move autoconf.h to include/generated drop explicit include of autoconf.h kbuild: move compile.h to include/generated kbuild: drop include/asm kbuild: do not check for include/asm-$ARCH ... Fixed non-conflicting clean merge of modpost.c as per comments from Stephen Rothwell (modpost.c had grown an include of linux/autoconf.h that needed to be changed to generated/autoconf.h)
2009-12-17sched: Fix broken assertionPeter Zijlstra
There's a preemption race in the set_task_cpu() debug check in that when we get preempted after setting task->state we'd still be on the rq proper, but fail the test. Check for preempted tasks, since those are always on the RQ. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <20091217121830.137155561@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-17perf events: Dont report side-band events on each cpu for per-task-per-cpu ↵Peter Zijlstra
events Acme noticed that his FORK/MMAP numbers were inflated by about the same factor as his cpu-count. This led to the discovery of a few more sites that need to respect the event->cpu filter. Reported-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <20091217121830.215333434@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-17perf events, x86/stacktrace: Make stack walking optionalFrederic Weisbecker
The current print_context_stack helper that does the stack walking job is good for usual stacktraces as it walks through all the stack and reports even addresses that look unreliable, which is nice when we don't have frame pointers for example. But we have users like perf that only require reliable stacktraces, and those may want a more adapted stack walker, so lets make this function a callback in stacktrace_ops that users can tune for their needs. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1261024834-5336-1-git-send-regression-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-17sched: Teach might_sleep() about preemptible RCUFrederic Weisbecker
In practice, it is harmless to voluntarily sleep in a rcu_read_lock() section if we are running under preempt rcu, but it is illegal if we build a kernel running non-preemptable rcu. Currently, might_sleep() doesn't notice sleepable operations under rcu_read_lock() sections if we are running under preemptable rcu because preempt_count() is left untouched after rcu_read_lock() in this case. But we want developers who test their changes under such config to notice the "sleeping while atomic" issues. So we add rcu_read_lock_nesting to prempt_count() in might_sleep() checks. [ v2: Handle rcu-tiny ] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> LKML-Reference: <1260991265-8451-1-git-send-regression-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-17kprobe-tracer: Check new event/group nameMasami Hiramatsu
Check new event/group name is same syntax as a C symbol. In other words, checking the name is as like as other tracepoint events. This can prevent user to create an event with useless name (e.g. foo|bar, foo*bar). Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Jason Baron <jbaron@redhat.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> LKML-Reference: <20091216222408.14459.68790.stgit@dhcp-100-2-132.bos.redhat.com> [ v2: minor cleanups ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-17sched: Make warning less noisyIngo Molnar
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170517.807938893@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-17cpumask: avoid dereferencing struct cpumaskRusty Russell
struct cpumask will be undefined soon with CONFIG_CPUMASK_OFFSTACK=y, to avoid them being declared on the stack. cpumask_bits() does what we want here (of course, this code is crap). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> To: Thomas Gleixner <tglx@linutronix.de>
2009-12-17cpumask: use cpu_online in kernel/perf_event.cRusty Russell
Also, we want to check against nr_cpu_ids, not num_possible_cpus(). The latter works, but the correct bounds check is < nr_cpu_ids. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> To: Thomas Gleixner <tglx@linutronix.de>
2009-12-17timers: Remove duplicate setting of new_base in __mod_timer()Simon Horman
new_base is set using per_cpu(tvec_bases, cpu) after selecting the desired value of cpu immediately below so this line is a unnecessary. Signed-off-by: Simon Horman <horms@verge.net.au> LKML-Reference: <20091217001542.GD25317@verge.net.au> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-12-17NOMMU: Optimise away the {dac_,}mmap_min_addr testsDavid Howells
In NOMMU mode clamp dac_mmap_min_addr to zero to cause the tests on it to be skipped by the compiler. We do this as the minimum mmap address doesn't make any sense in NOMMU mode. mmap_min_addr and round_hint_to_min() can be discarded entirely in NOMMU mode. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2009-12-16[sysctl] Fix breakage on systems with older glibcAndi Kleen
As predicted during code review, the sysctl(2) changes made systems with old glibc nearly unusable. About every command gives a: warning: process `ls' used the deprecated sysctl system call with 1.4 warning in the log. I see this on a SUSE 10.0 system with glibc 2.3.5. Don't warn for this common case. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16Merge branch 'perf-fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (52 commits) perf record: Use per-task-per-cpu events for inherited events perf record: Properly synchronize child creation perf events: Allow per-task-per-cpu counters perf diff: Percent calcs should use double values perf diff: Change the default sort order to "dso,symbol" perf diff: Use perf_session__fprintf_hists just like 'perf record' perf report: Fix cut'n'paste error recently introduced perf session: Move perf report specific hits out of perf_session__fprintf_hists perf tools: Move hist entries printing routines from perf report perf report: Generalize perf_session__fprintf_hists() perf symbols: Move symbol filtering to event__preprocess_sample() perf symbols: Adopt the strlists for dso, comm perf symbols: Make symbol_conf global perf probe: Fix to show which probe point is not found perf probe: Check symbols in symtab/kallsyms perf probe: Check build-id of vmlinux perf probe: Reject second attempt of adding same-name event perf probe: Support event name for --add option perf probe: Add glob matching support on --del perf probe: Use strlist__for_each macros in probe-event.c ...
2009-12-16Merge branch 'tracing-fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: tracing: Fix return of trace_dump_stack() ksym_tracer: Fix bad cast tracing/power: Remove two exports tracing: Change event->profile_count to be int type tracing: Simplify trace_option_write() tracing: Remove useless trace option tracing: Use seq file for trace_clock tracing: Use seq file for trace_options function-graph: Allow writing the same val to set_graph_function ftrace: Call trace_parser_clear() properly ftrace: Return EINVAL when writing invalid val to set_ftrace_filter tracing: Move a printk out of ftrace_raw_reg_event_foo() tracing: Pull up calls to trace_define_common_fields() tracing: Extract duplicate ftrace_raw_init_event_foo() ftrace.h: Use common pr_info fmt string tracing: Add stack trace to irqsoff tracer tracing: Add trace_dump_stack() ring-buffer: Move resize integrity check under reader lock ring-buffer: Use sync sched protection on ring buffer resizing tracing: Fix wrong usage of strstrip in trace_ksyms
2009-12-16Merge branch 'module' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus * 'module' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus: modpost: fix segfault with short symbol names module: handle ppc64 relocating kcrctabs when CONFIG_RELOCATABLE=y Kbuild: clear marker out of modpost module: make MODULE_SYMBOL_PREFIX into a CONFIG option ARM: unexport symbols used to implement floating point emulation ARM: use unified discard definition in linker script x86: don't export inline function sparc64: don't export static inline pci_ functions
2009-12-16Merge git://git.infradead.org/mtd-2.6Linus Torvalds
* git://git.infradead.org/mtd-2.6: (90 commits) jffs2: Fix long-standing bug with symlink garbage collection. mtd: OneNAND: Fix test of unsigned in onenand_otp_walk() mtd: cfi_cmdset_0002, fix lock imbalance Revert "mtd: move mxcnd_remove to .exit.text" mtd: m25p80: add support for Macronix MX25L4005A kmsg_dump: fix build for CONFIG_PRINTK=n mtd: nandsim: add support for 4KiB pages mtd: mtdoops: refactor as a kmsg_dumper mtd: mtdoops: make record size configurable mtd: mtdoops: limit the maximum mtd partition size mtd: mtdoops: keep track of used/unused pages in an array mtd: mtdoops: several minor cleanups core: Add kernel message dumper to call on oopses and panics mtd: add ARM pismo support mtd: pxa3xx_nand: Fix PIO data transfer mtd: nand: fix multi-chip suspend problem mtd: add support for switching old SST chips into QRY mode mtd: fix M29W800D dev_id and uaddr mtd: don't use PF_MEMALLOC mtd: Add bad block table overrides to Davinci NAND driver ... Fixed up conflicts (mostly trivial) in drivers/mtd/devices/m25p80.c drivers/mtd/maps/pcmciamtd.c drivers/mtd/nand/pxa3xx_nand.c kernel/printk.c
2009-12-16sched: Simplify set_task_cpu()Peter Zijlstra
Rearrange code a bit now that its a simpler function. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170518.269101883@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16sched: Remove the cfs_rq dependency from set_task_cpu()Peter Zijlstra
In order to remove the cfs_rq dependency from set_task_cpu() we need to ensure the task is cfs_rq invariant for all callsites. The simple approach is to substract cfs_rq->min_vruntime from se->vruntime on dequeue, and add cfs_rq->min_vruntime on enqueue. However, this has the downside of breaking FAIR_SLEEPERS since we loose the old vruntime as we only maintain the relative position. To solve this, we observe that we only migrate runnable tasks, we do this using deactivate_task(.sleep=0) and activate_task(.wakeup=0), therefore we can restrain the min_vruntime invariance to that state. The only other case is wakeup balancing, since we want to maintain the old vruntime we cannot make it relative on dequeue, but since we don't migrate inactive tasks, we can do so right before we activate it again. This is where we need the new pre-wakeup hook, we need to call this while still holding the old rq->lock. We could fold it into ->select_task_rq(), but since that has multiple callsites and would obfuscate the locking requirements, that seems like a fudge. This leaves the fork() case, simply make sure that ->task_fork() leaves the ->vruntime in a relative state. This covers all cases where set_task_cpu() gets called, and ensures it sees a relative vruntime. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170518.191697025@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16sched: Add pre and post wakeup hooksPeter Zijlstra
As will be apparent in the next patch, we need a pre wakeup hook for sched_fair task migration, hence rename the post wakeup hook and one pre wakeup. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170518.114746117@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16sched: Move kthread_bind() back to kthread.cPeter Zijlstra
Since kthread_bind() lost its dependencies on sched.c, move it back where it came from. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170518.039524041@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16sched: Fix select_task_rq() vs hotplug issuesPeter Zijlstra
Since select_task_rq() is now responsible for guaranteeing ->cpus_allowed and cpu_active_mask, we need to verify this. select_task_rq_rt() can blindly return smp_processor_id()/task_cpu() without checking the valid masks, select_task_rq_fair() can do the same in the rare case that all SD_flags are disabled. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170517.961475466@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16sched: Fix sched_exec() balancingPeter Zijlstra
Since we access ->cpus_allowed without holding rq->lock we need a retry loop to validate the result, this comes for near free when we merge sched_migrate_task() into sched_exec() since that already does the needed check. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170517.884743662@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16sched: Ensure set_task_cpu() is never called on blocked tasksPeter Zijlstra
In order to clean up the set_task_cpu() rq dependencies we need to ensure it is never called on blocked tasks because such usage does not pair with consistent rq->lock usage. This puts the migration burden on ttwu(). Furthermore we need to close a race against changing ->cpus_allowed, since select_task_rq() runs with only preemption disabled. For sched_fork() this is safe because the child isn't in the tasklist yet, for wakeup we fix this by synchronizing set_cpus_allowed_ptr() against TASK_WAKING, which leaves sched_exec to be a problem This also closes a hole in (6ad4c1888 sched: Fix balance vs hotplug race) where ->select_task_rq() doesn't validate the result against the sched_domain/root_domain. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170517.807938893@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16sched: Use TASK_WAKING for fork wakupsPeter Zijlstra
For later convenience use TASK_WAKING for fresh tasks. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170517.732561278@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16sched: Select_task_rq_fair() must honour SD_LOAD_BALANCEPeter Zijlstra
We should skip !SD_LOAD_BALANCE domains. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170517.653578430@chello.nl> CC: stable@kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16sched: Fix task_hot() test orderPeter Zijlstra
Make sure not to access sched_fair fields before verifying it is indeed a sched_fair task. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> CC: stable@kernel.org LKML-Reference: <20091216170517.577998058@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16sched: Fix set_cpu_active() in cpu_down()Xiaotian Feng
Sachin found cpu hotplug test failures on powerpc, which made the kernel hang on his POWER box. The problem is that we fail to re-activate a cpu when a hot-unplug fails. Fix this by moving the de-activation into _cpu_down after doing the initial checks. Remove the synchronize_sched() calls and rely on those implied by rebuilding the sched domains using the new mask. Reported-by: Sachin Sant <sachinp@in.ibm.com> Signed-off-by: Xiaotian Feng <dfeng@redhat.com> Tested-by: Sachin Sant <sachinp@in.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170517.500272612@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16Merge branch 'linus' into sched/urgentIngo Molnar
Conflicts: kernel/sched_idletask.c Merge reason: resolve the conflicts, pick up latest changes. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16perf events: Allow per-task-per-cpu countersPeter Zijlstra
In order to allow for per-task-per-cpu counters, useful for scalability when profiling task hierarchies, we allow installing events with event->cpu != -1 in task contexts. __perf_event_sched_in() already skips events where ->cpu mis-matches the current cpu, fix up __perf_install_in_context() and __perf_event_enable() to also respect this filter. This does lead to vary hard to interpret enabled/running times for such counters, but I don't see a simple solution for that. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: fweisbec@gmail.com Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <20091216165904.831451147@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16kexec: premit reduction of the reserved memory sizeAmerigo Wang
Implement shrinking the reserved memory for crash kernel, if it is more than enough. For example, if you have already reserved 128M, now you just want 100M, you can do: # echo $((100*1024*1024)) > /sys/kernel/kexec_crash_size Note, you can only do this before loading the crash kernel. Signed-off-by: WANG Cong <amwang@redhat.com> Cc: Neil Horman <nhorman@redhat.com> Acked-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Andi Kleen <andi@firstfloor.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16pid: reduce code size by using a pointer to iterate over arrayAndré Goddard Rosa
It decreases code size by 16 bytes on my gcc 4.4.1 on Core 2: text data bss dec hex filename 4314 2216 8 6538 198a kernel/pid.o-BEFORE 4298 2216 8 6522 197a kernel/pid.o-AFTER Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16pid: tighten pidmap spinlock critical section by removing kfree()André Goddard Rosa
Avoid calling kfree() under pidmap spinlock, calling it afterwards. Normally kfree() is fast, but sometimes it can be slow, so avoid calling it under the spinlock if we can do it. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16signals: check ->group_stop_count after tracehook_get_signal()Oleg Nesterov
Move the call to do_signal_stop() down, after tracehook call. This makes ->group_stop_count condition visible to tracers before do_signal_stop() will participate in this group-stop. Currently the patch has no effect, tracehook_get_signal() always returns 0. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Roland McGrath <roland@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16signals: kill force_sig_specific()Oleg Nesterov
Kill force_sig_specific(), this trivial wrapper has no callers. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: Roland McGrath <roland@redhat.com> Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16signals: cosmetic, collect_signal: use SI_USEROleg Nesterov
Trivial, s/0/SI_USER/ in collect_signal() for grep. This is a bit confusing, we don't know the source of this signal. But we don't care, and "info->si_code = 0" is imho worse. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: Roland McGrath <roland@redhat.com> Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16signals: send_signal: use si_fromuser() to detect from_ancestor_nsOleg Nesterov
Change send_signal() to use si_fromuser(). From now SEND_SIG_NOINFO triggers the "from_ancestor_ns" check. This fixes reparent_thread()->group_send_sig_info(pdeath_signal) behaviour, before this patch send_signal() does not detect the cross-namespace case when the child of the dying parent belongs to the sub-namespace. This patch can affect the behaviour of send_sig(), kill_pgrp() and kill_pid() when the caller sends the signal to the sub-namespace with "priv == 0" but surprisingly all callers seem to use them correctly, including disassociate_ctty(on_exit). Except: drivers/staging/comedi/drivers/addi-data/*.c incorrectly use send_sig(priv => 0). But his is minor and should be fixed anyway. Reported-by: Daniel Lezcano <dlezcano@fr.ibm.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: Roland McGrath <roland@redhat.com> Reviewed-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16signals: SEND_SIG_NOINFO should be considered as SI_FROMUSER()Oleg Nesterov
No changes in compiled code. The patch adds the new helper, si_fromuser() and changes check_kill_permission() to use this helper. The real effect of this patch is that from now we "officially" consider SEND_SIG_NOINFO signal as "from user-space" signals. This is already true if we look at the code which uses SEND_SIG_NOINFO, except __send_signal() has another opinion - see the next patch. The naming of these special SEND_SIG_XXX siginfo's is really bad imho. From __send_signal()'s pov they mean SEND_SIG_NOINFO from user SEND_SIG_PRIV from kernel SEND_SIG_FORCED no info Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: Roland McGrath <roland@redhat.com> Reviewed-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16ptrace: copy_process() should disable steppingOleg Nesterov
If the tracee calls fork() after PTRACE_SINGLESTEP, the forked child starts with TIF_SINGLESTEP/X86_EFLAGS_TF bits copied from ptraced parent. This is not right, especially when the new child is not auto-attaced: in this case it is killed by SIGTRAP. Change copy_process() to call user_disable_single_step(). Tested on x86. Test-case: #include <stdio.h> #include <unistd.h> #include <signal.h> #include <sys/ptrace.h> #include <sys/wait.h> #include <assert.h> int main(void) { int pid, status; if (!(pid = fork())) { assert(ptrace(PTRACE_TRACEME) == 0); kill(getpid(), SIGSTOP); if (!fork()) { /* kernel bug: this child will be killed by SIGTRAP */ printf("Hello world\n"); return 43; } wait(&status); return WEXITSTATUS(status); } for (;;) { assert(pid == wait(&status)); if (WIFEXITED(status)) break; assert(ptrace(PTRACE_SINGLESTEP, pid, 0,0) == 0); } assert(WEXITSTATUS(status) == 43); return 0; } Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Roland McGrath <roland@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16memcg: coalesce uncharge during unmap/truncateKAMEZAWA Hiroyuki
In massive parallel enviroment, res_counter can be a performance bottleneck. One strong techinque to reduce lock contention is reducing calls by coalescing some amount of calls into one. Considering charge/uncharge chatacteristic, - charge is done one by one via demand-paging. - uncharge is done by - in chunk at munmap, truncate, exit, execve... - one by one via vmscan/paging. It seems we have a chance to coalesce uncharges for improving scalability at unmap/truncation. This patch is a for coalescing uncharge. For avoiding scattering memcg's structure to functions under /mm, this patch adds memcg batch uncharge information to the task. A reason for per-task batching is for making use of caller's context information. We do batched uncharge (deleyed uncharge) when truncation/unmap occurs but do direct uncharge when uncharge is called by memory reclaim (vmscan.c). The degree of coalescing depends on callers - at invalidate/trucate... pagevec size - at unmap ....ZAP_BLOCK_SIZE (memory itself will be freed in this degree.) Then, we'll not coalescing too much. On x86-64 8cpu server, I tested overheads of memcg at page fault by running a program which does map/fault/unmap in a loop. Running a task per a cpu by taskset and see sum of the number of page faults in 60secs. [without memcg config] 40156968 page-faults # 0.085 M/sec ( +- 0.046% ) 27.67 cache-miss/faults [root cgroup] 36659599 page-faults # 0.077 M/sec ( +- 0.247% ) 31.58 miss/faults [in a child cgroup] 18444157 page-faults # 0.039 M/sec ( +- 0.133% ) 69.96 miss/faults [child with this patch] 27133719 page-faults # 0.057 M/sec ( +- 0.155% ) 47.16 miss/faults We can see some amounts of improvement. (root cgroup doesn't affected by this patch) Another patch for "charge" will follow this and above will be improved more. Changelog(since 2009/10/02): - renamed filed of memcg_batch (as pages to bytes, memsw to memsw_bytes) - some clean up and commentary/description updates. - added initialize code to copy_process(). (possible bug fix) Changelog(old): - fixed !CONFIG_MEM_CGROUP case. - rebased onto the latest mmotm + softlimit fix patches. - unified patch for callers - added commetns. - make ->do_batch as bool. - removed css_get() at el. We don't need it. Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16const: constify remaining pipe_buf_operationsAlexey Dobriyan
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16timecompare: fix half-Y2K38 problem in timecompare_update while calculating ↵Barry Song
offset ktime will overflow from 03:14:07 UTC on Tuesday, 19 January 2038, ktime_add() in timecompare_update() will overflow a half earlier. As a result, wrong offset will be gotten, then cause some strange problems. Signed-off-by: Barry Song <21cnbao@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: Patrick Ohly <patrick.ohly@intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: John Stultz <johnstul@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>