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* Merge branch 'tip/perf/core' of ↵Ingo Molnar2010-07-237-14/+76
|\ | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into perf/core
| * trace: strlen() return doesn't account for the NULLDan Carpenter2010-07-221-1/+1
| | | | | | | | | | | | | | | | | | | | | | We need to add one to the strlen() return because of the NULL character. The type->name here generally comes from the kernel and I don't think any of them come close to being MAX_TRACER_SIZE (100) characters long so this is basically a cleanup. Signed-off-by: Dan Carpenter <error27@gmail.com> LKML-Reference: <20100710100644.GV19184@bicker> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing: Shrink max latency ringbuffer if unnecessaryKOSAKI Motohiro2010-07-214-6/+38
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Documentation/trace/ftrace.txt says buffer_size_kb: This sets or displays the number of kilobytes each CPU buffer can hold. The tracer buffers are the same size for each CPU. The displayed number is the size of the CPU buffer and not total size of all buffers. The trace buffers are allocated in pages (blocks of memory that the kernel uses for allocation, usually 4 KB in size). If the last page allocated has room for more bytes than requested, the rest of the page will be used, making the actual allocation bigger than requested. ( Note, the size may not be a multiple of the page size due to buffer management overhead. ) This can only be updated when the current_tracer is set to "nop". But it's incorrect. currently total memory consumption is 'buffer_size_kb x CPUs x 2'. Why two times difference is there? because ftrace implicitly allocate the buffer for max latency too. That makes sad result when admin want to use large buffer. (If admin want full logging and makes detail analysis). example, If admin have 24 CPUs machine and write 200MB to buffer_size_kb, the system consume ~10GB memory (200MB x 24 x 2). umm.. 5GB memory waste is usually unacceptable. Fortunatelly, almost all users don't use max latency feature. The max latency buffer can be disabled easily. This patch shrink buffer size of the max latency buffer if unnecessary. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> LKML-Reference: <20100701104554.DA2D.A69D9226@jp.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing: Reduce latency and remove percpu trace_seqLai Jiangshan2010-07-201-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __print_flags() and __print_symbolic() use percpu trace_seq: 1) Its memory is allocated at compile time, it wastes memory if we don't use tracing. 2) It is percpu data and it wastes more memory for multi-cpus system. 3) It disables preemption when it executes its core routine "trace_seq_printf(s, "%s: ", #call);" and introduces latency. So we move this trace_seq to struct trace_iterator. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> LKML-Reference: <4C078350.7090106@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * trace: Reorder struct ring_buffer_per_cpu to remove padding on 64bitRichard Kennedy2010-07-201-1/+1
| | | | | | | | | | | | | | | | | | | | Reorder structure to remove 8 bytes of padding on 64 bit builds. This shrinks the size to 128 bytes so allowing allocation from a smaller slab & needed one fewer cache lines. Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk> LKML-Reference: <1269516456.2054.8.camel@localhost> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * tracing: Allow to disable cmdline recordingLi Zefan2010-07-203-3/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We found that even enabling a single trace event that will rarely be triggered can add big overhead to context switch. (lmbench context switch test) ------------------------------------------------- 2p/0K 2p/16K 2p/64K 8p/16K 8p/64K 16p/16K 16p/64K ctxsw ctxsw ctxsw ctxsw ctxsw ctxsw ctxsw ------ ------ ------ ------ ------ ------- ------- 2.19 2.3 2.21 2.56 2.13 2.54 2.07 2.39 2.51 2.35 2.75 2.27 2.81 2.24 The overhead is 6% ~ 11%. It's because when a trace event is enabled 3 tracepoints (sched_switch, sched_wakeup, sched_wakeup_new) will be activated to map pid to cmdname. We'd like to avoid this overhead, so add a trace option '(no)record-cmd' to allow to disable cmdline recording. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <4C2D57F4.2050204@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | Merge branch 'perf/core' of ↵Ingo Molnar2010-07-218-524/+15
|\ \ | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into perf/core
| * | tracing: Use generic_file_llseek for debugfsArnd Bergmann2010-07-201-0/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The default for llseek will change to no_llseek, so the tracing debugfs files need to add explicit .llseek assignments. Since we're dealing with regular files from a VFS perspective, use generic_file_llseek. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: John Kacur <jkacur@redhat.com> Cc: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <1278538820-1392-10-git-send-email-arnd@arndb.de> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
| * | tracing: Remove special tracesFrederic Weisbecker2010-07-205-146/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Special traces type was only used by sysprof. Lets remove it now that sysprof ftrace plugin has been dropped. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Soeren Sandmann <sandmann@daimi.au.dk> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Li Zefan <lizf@cn.fujitsu.com>
| * | tracing: Remove sysprof ftrace pluginFrederic Weisbecker2010-07-206-378/+0
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The sysprof ftrace plugin doesn't seem to be seriously used somewhere. There is a branch in the sysprof tree that makes an interface to it, but the real sysprof tool uses either its own module or perf events. Drop the sysprof ftrace plugin then, as it's mostly useless. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Soeren Sandmann <sandmann@daimi.au.dk> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Li Zefan <lizf@cn.fujitsu.com>
* | Merge branch 'linus' into perf/coreIngo Molnar2010-07-211-0/+6
|\ \ | |/ |/| | | | | | | Merge reason: Pick up the latest perf fixes. Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * kmemleak: Add support for NO_BOOTMEM configurationsCatalin Marinas2010-07-191-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | With commits 08677214 and 59be5a8e, alloc_bootmem()/free_bootmem() and friends use the early_res functions for memory management when NO_BOOTMEM is enabled. This patch adds the kmemleak calls in the corresponding code paths for bootmem allocations. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Yinghai Lu <yinghai@kernel.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: stable@kernel.org
* | tracing: Remove ksym tracerFrederic Weisbecker2010-07-156-606/+0
| | | | | | | | | | | | | | | | | | | | | | | | The ksym (breakpoint) ftrace plugin has been superseded by perf tools that are much more poweful to use the cpu breakpoints. This tracer doesn't bring more feature. It has been deprecated for a while now, lets remove it. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Prasad <prasad@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@elte.hu>
* | Merge branch 'perf/core' of ↵Ingo Molnar2010-07-061-78/+292
|\ \ | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux-2.6 into perf/core
| * | tracing/kprobes: Support "string" typeMasami Hiramatsu2010-07-051-78/+292
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Support string type tracing and printing in kprobe-tracer. This allows user to trace string data in kernel including __user data. Note that sometimes __user data may not be accessed if it is paged-out (sorry, but kprobes operation should be done in atomic, we can not wait for page-in). Commiter note: Fixed up conflicts with b7e2ece. Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20100519195724.2885.18788.stgit@localhost6.localdomain6> Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | | Merge commit 'v2.6.35-rc4' into perf/coreIngo Molnar2010-07-055-34/+33
|\ \ \ | |/ / |/| / | |/ | | | | Merge reason: Pick up the latest perf fixes Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * module: initialize module dynamic debug laterYehuda Sadeh2010-07-041-8/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | We should initialize the module dynamic debug datastructures only after determining that the module is not loaded yet. This fixes a bug that introduced in 2.6.35-rc2, where when a trying to load a module twice, we also load it's dynamic printing data twice which causes all sorts of nasty issues. Also handle the dynamic debug cleanup later on failure. Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (removed a #ifdef) Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * Merge branch 'sched-fixes-for-linus' of ↵Linus Torvalds2010-07-022-10/+10
| |\ | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: sched: Cure nr_iowait_cpu() users init: Fix comment init, sched: Fix race between init and kthreadd
| | * sched: Cure nr_iowait_cpu() usersPeter Zijlstra2010-07-012-10/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 0224cf4c5e (sched: Intoduce get_cpu_iowait_time_us()) broke things by not making sure preemption was indeed disabled by the callers of nr_iowait_cpu() which took the iowait value of the current cpu. This resulted in a heap of preempt warnings. Cure this by making nr_iowait_cpu() take a cpu number and fix up the callers to pass in the right number. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Maxim Levitsky <maximlevitsky@gmail.com> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Jiri Slaby <jslaby@suse.cz> Cc: linux-pm@lists.linux-foundation.org LKML-Reference: <1277968037.1868.120.camel@laptop> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | futex: futex_find_get_task remove credentails checkMichal Hocko2010-06-301-13/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | futex_find_get_task is currently used (through lookup_pi_state) from two contexts, futex_requeue and futex_lock_pi_atomic. None of the paths looks it needs the credentials check, though. Different (e)uids shouldn't matter at all because the only thing that is important for shared futex is the accessibility of the shared memory. The credentail check results in glibc assert failure or process hang (if glibc is compiled without assert support) for shared robust pthread mutex with priority inheritance if a process tries to lock already held lock owned by a process with a different euid: pthread_mutex_lock.c:312: __pthread_mutex_lock_full: Assertion `(-(e)) != 3 || !robust' failed. The problem is that futex_lock_pi_atomic which is called when we try to lock already held lock checks the current holder (tid is stored in the futex value) to get the PI state. It uses lookup_pi_state which in turn gets task struct from futex_find_get_task. ESRCH is returned either when the task is not found or if credentials check fails. futex_lock_pi_atomic simply returns if it gets ESRCH. glibc code, however, doesn't expect that robust lock returns with ESRCH because it should get either success or owner died. Signed-off-by: Michal Hocko <mhocko@suse.cz> Acked-by: Darren Hart <dvhltc@us.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Nick Piggin <npiggin@suse.de> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | kexec: fix Oops in crash_shrink_memory()Pavan Naregundi2010-06-291-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When crashkernel is not enabled, "echo 0 > /sys/kernel/kexec_crash_size" OOPSes the kernel in crash_shrink_memory. This happens when crash_shrink_memory tries to release the 'crashk_res' resource which are not reserved. Also value of "/sys/kernel/kexec_crash_size" shows as 1, which should be 0. This patch fixes the OOPS in crash_shrink_memory and shows "/sys/kernel/kexec_crash_size" as 0 when crash kernel memory is not reserved. Signed-off-by: Pavan Naregundi <pavan@linux.vnet.ibm.com> Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com> Cc: Simon Horman <horms@verge.net.au> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | tracing: Use class->reg() for all registering of eventsSteven Rostedt2010-06-282-35/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Because kprobes and syscalls need special processing to register events, the class->reg() method was created to handle the differences. But instead of creating a default ->reg for perf and ftrace events, the code was scattered with: if (class->reg) class->reg(); else default_reg(); This is messy and can also lead to bugs. This patch cleans up this code and creates a default reg() entry for the events allowing for the code to directly call the class->reg() without the condition. Reported-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | | tracing/function-graph: Use correct string size for snprintfChase Douglas2010-06-281-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The nsecs_str string is a local variable defined as: char nsecs_str[5]; It is possible for the snprintf call to use a size value larger than the size of the string. This should not cause a buffer overrun as it is written now due to the value for the string format "%03lu" can not be larger than 1000. However, this change makes it correct. By making the size correct we guard against potential future changes that could actually cause a buffer overrun. Signed-off-by: Chase Douglas <chase.douglas@canonical.com> LKML-Reference: <1276619355-18116-1-git-send-email-chase.douglas@canonical.com> [ added 'UL' to number 8 to fix gcc warning comparing it to sizeof() ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | | tracing: Remove open-coded __trace_add_event_call()Li Zefan2010-06-281-51/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | Let trace_module_add_events() and event_trace_init() call __trace_add_event_call(). Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <4BFA37E9.1020106@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | | tracing: Remove redundant raw_init callbacksLi Zefan2010-06-282-16/+2
| | | | | | | | | | | | | | | | | | | | | | | | raw_init callback is optional. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <4BFA37D4.7070500@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | | tracing: Remove test of NULL define_fields callbackLi Zefan2010-06-282-24/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | Every event (or event class) has it's define_fields callback, so the test is redundant. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <4BFA37BC.8080707@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | | tracing: Don't allocate common fields for every trace eventsLi Zefan2010-06-283-52/+81
| | | | | | | | | | | | | | | | | | | | | | | | | | | Every event has the same common fields, so it's a big waste of memory to have a copy of those fields for every event. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <4BFA3759.30105@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | | tracing: Use a global field list for all syscall exit eventsLi Zefan2010-06-281-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All syscall exit events have the same fields. The kernel size drops 2.5K: text data bss dec hex filename 7018612 2034376 7251132 16304120 f8c7f8 vmlinux.o.orig 7018612 2031888 7251132 16301632 f8be40 vmlinux.o Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <4BFA3746.8070100@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | | Merge branch 'linus' into perf/coreThomas Gleixner2010-06-289-81/+107
|\ \ \ | |/ / | | | | | | | | | | | | Reason: Further changes conflict with upstream fixes Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | Merge branch 'perf-fixes-for-linus' of ↵Linus Torvalds2010-06-281-1/+3
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: tracing: Fix undeclared ENOSYS in include/linux/tracepoint.h perf record: prevent kill(0, SIGTERM); perf session: Remove threads from tree on PERF_RECORD_EXIT perf/tracing: Fix regression of perf losing kprobe events perf_events: Fix Intel Westmere event constraints perf record: Don't call newt functions when not initialized
| | * | perf/tracing: Fix regression of perf losing kprobe eventsSteven Rostedt2010-06-101-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With the addition of the code to shrink the kernel tracepoint infrastructure, we lost kprobes being traced by perf. The reason is that I tested if the "tp_event->class->perf_probe" existed before enabling it. This prevents "ftrace only" events (like the function trace events) from being enabled by perf. Unfortunately, kprobe events do not use perf_probe. This causes kprobes to be missed by perf. To fix this, we add the test to see if "tp_event->class->reg" exists as well as perf_probe. Normal trace events have only "perf_probe" but no "reg" function, and kprobes and syscalls have the "reg" but no "perf_probe". The ftrace unique events do not have either, so this is a valid test. If a kprobe or syscall is not to be probed by perf, the "reg" function is called anyway, and will return a failure and prevent perf from probing it. Reported-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * | | Merge branch 'irq-fixes-for-linus' of ↵Linus Torvalds2010-06-281-0/+3
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: genirq: Deal with desc->set_type() changing desc->chip
| | * | | genirq: Deal with desc->set_type() changing desc->chipThomas Gleixner2010-06-091-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The set_type() function can change the chip implementation when the trigger mode changes. That might result in using an non-initialized irq chip when called from __setup_irq() or when called via set_irq_type() on an already enabled irq. The set_irq_type() function should not be called on an enabled irq, but because we forgot to put a check into it, we have a bunch of users which grew the habit of doing that and it never blew up as the function is serialized via desc->lock against all users of desc->chip and they never hit the non-initialized irq chip issue. The easy fix for the __setup_irq() issue would be to move the irq_chip_set_defaults(desc->chip) call after the trigger setting to make sure that a chip change is covered. But as we have already users, which do the type setting after request_irq(), the safe fix for now is to call irq_chip_set_defaults() from __irq_set_trigger() when desc->set_type() changed the irq chip. It needs a deeper analysis whether we should refuse to change the chip on an already enabled irq, but that'd be a large scale change to fix all the existing users. So that's neither stable nor 2.6.35 material. Reported-by: Esben Haabendal <eha@doredevelopment.dk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: linuxppc-dev <linuxppc-dev@ozlabs.org> Cc: stable@kernel.org
| * | | | Merge branch 'sched-fixes-for-linus' of ↵Linus Torvalds2010-06-281-59/+65
| |\ \ \ \ | | | |_|/ | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: sched: Prevent compiler from optimising the sched_avg_update() loop sched: Fix over-scheduling bug sched: Fix PROVE_RCU vs cpu_cgroup
| | * | | sched: Prevent compiler from optimising the sched_avg_update() loopWill Deacon2010-06-251-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | GCC 4.4.1 on ARM has been observed to replace the while loop in sched_avg_update with a call to uldivmod, resulting in the following build failure at link-time: kernel/built-in.o: In function `sched_avg_update': kernel/sched.c:1261: undefined reference to `__aeabi_uldivmod' kernel/sched.c:1261: undefined reference to `__aeabi_uldivmod' make: *** [.tmp_vmlinux1] Error 1 This patch introduces a fake data hazard to the loop body to prevent the compiler optimising the loop away. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: <stable@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | sched: Fix over-scheduling bugAlex,Shi2010-06-181-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit e70971591 ("sched: Optimize unused cgroup configuration") introduced an imbalanced scheduling bug. If we do not use CGROUP, function update_h_load won't update h_load. When the system has a large number of tasks far more than logical CPU number, the incorrect cfs_rq[cpu]->h_load value will cause load_balance() to pull too many tasks to the local CPU from the busiest CPU. So the busiest CPU keeps going in a round robin. That will hurt performance. The issue was found originally by a scientific calculation workload that developed by Yanmin. With that commit, the workload performance drops about 40%. CPU before after 00 : 2 : 7 01 : 1 : 7 02 : 11 : 6 03 : 12 : 7 04 : 6 : 6 05 : 11 : 7 06 : 10 : 6 07 : 12 : 7 08 : 11 : 6 09 : 12 : 6 10 : 1 : 6 11 : 1 : 6 12 : 6 : 6 13 : 2 : 6 14 : 2 : 6 15 : 1 : 6 Reviewed-by: Yanmin zhang <yanmin.zhang@intel.com> Signed-off-by: Alex Shi <alex.shi@intel.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1276754893.9452.5442.camel@debian> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | | sched: Fix PROVE_RCU vs cpu_cgroupPeter Zijlstra2010-06-081-56/+59
| | |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PROVE_RCU has a few issues with the cpu_cgroup because the scheduler typically holds rq->lock around the css rcu derefs but the generic cgroup code doesn't (and can't) know about that lock. Provide means to add extra checks to the css dereference and use that in the scheduler to annotate its users. The addition of rq->lock to these checks is correct because the cgroup_subsys::attach() method takes the rq->lock for each task it moves, therefore by holding that lock, we ensure the task is pinned to the current cgroup and the RCU derefence is valid. That leaves one genuine race in __sched_setscheduler() where we used task_group() without holding any of the required locks and thus raced with the cgroup code. Solve this by moving the check under the appropriate lock. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | Merge branch 'timers-fixes-for-linus' of ↵Linus Torvalds2010-06-281-4/+1
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: nohz: Fix nohz ratelimit
| | * | | nohz: Fix nohz ratelimitPeter Zijlstra2010-06-171-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Chris Wedgwood reports that 39c0cbe (sched: Rate-limit nohz) causes a serial console regression, unresponsiveness, and indeed it does. The reason is that the nohz code is skipped even when the tick was already stopped before the nohz_ratelimit(cpu) condition changed. Move the nohz_ratelimit() check to the other conditions which prevent long idle sleeps. Reported-by: Chris Wedgwood <cw@f00f.org> Tested-by: Brian Bloniarz <bmb@athenacr.com> Signed-off-by: Mike Galbraith <efault@gmx.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Greg KH <gregkh@suse.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Jef Driesen <jefdriesen@telenet.be> LKML-Reference: <1276790557.27822.516.camel@twins> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | Merge branch 'core-fixes-for-linus' of ↵Linus Torvalds2010-06-282-0/+11
| |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: sched: silence PROVE_RCU in sched_fork() idr: fix RCU lockdep splat in idr_get_next() rcu: apply RCU protection to wake_affine()
| | * | | | sched: silence PROVE_RCU in sched_fork()Peter Zijlstra2010-06-231-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Because cgroup_fork() is ran before sched_fork() [ from copy_process() ] and the child's pid is not yet visible the child is pinned to its cgroup. Therefore we can silence this warning. A nicer solution would be moving cgroup_fork() to right after dup_task_struct() and exclude PF_STARTING from task_subsys_state(). Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
| | * | | | rcu: apply RCU protection to wake_affine()Daniel J Blueman2010-06-231-0/+2
| | |/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The task_group() function returns a pointer that must be protected by either RCU, the ->alloc_lock, or the cgroup lock (see the rcu_dereference_check() in task_subsys_state(), which is invoked by task_group()). The wake_affine() function currently does none of these, which means that a concurrent update would be within its rights to free the structure returned by task_group(). Because wake_affine() uses this structure only to compute load-balancing heuristics, there is no reason to acquire either of the two locks. Therefore, this commit introduces an RCU read-side critical section that starts before the first call to task_group() and ends after the last use of the "tg" pointer returned from task_group(). Thanks to Li Zefan for pointing out the need to extend the RCU read-side critical section from that proposed by the original patch. Signed-off-by: Daniel J Blueman <daniel.blueman@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
| * | | | Merge branch 'bugzilla-13931-sleep-nvs' into releaseLen Brown2010-06-124-17/+24
| |\ \ \ \ | | |/ / / | |/| | | | | | | | | | | | | | | | | | | | | | | Conflicts: drivers/acpi/sleep.c Signed-off-by: Len Brown <len.brown@intel.com>
| | * | | suspend: Move NVS save/restore code to generic suspend functionalityMatthew Garrett2010-06-104-17/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Saving platform non-volatile state may be required for suspend to RAM as well as hibernation. Move it to more generic code. Signed-off-by: Matthew Garrett <mjg@redhat.com> Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Tested-by: Maxim Levitsky <maximlevitsky@gmail.com> Signed-off-by: Len Brown <len.brown@intel.com>
* | | | | hw_breakpoints: Fix per task breakpoint trackingFrederic Weisbecker2010-06-241-37/+41
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Freeing a perf event can happen in several ways. A task calls perf_event_exit_task() right before exiting. This helper will detach all the events from the task context and queue their removal through free_event() if they are child tasks. The task also loses its context reference there. Releasing the breakpoint slot from the constraint table is made from free_event() that calls release_bp_slot(). We count the number of breakpoints this task is running by looking at the task's perf_event_ctxp and iterating through its attached events. But at this time, the reference to this context has been cleaned up already. So looking at the event->ctx instead of task->perf_event_ctxp to count the remaining breakpoints should solve the problem. At least it would for child breakpoints, but not for parent ones. If the parent exits before the child, it will remove all its events from the context but free_event() will be called later, on fd release time. And checking the number of breakpoints the task has attached to its context at this time is unreliable as all events have been removed from the context. To solve this, we keep track of the list of per task breakpoints. On top of it, we maintain our array of numbers of breakpoints used by the tasks. We use the context address as a task id. So, instead of looking at the number of events attached to a context, we walk through our list of per task breakpoints and count the number of breakpoints that use the same ctx than the one to be reserved or released from the constraint table, and update the count on top of this result. In the meantime it solves a bad refcounting, it also solves a warning, reported by Paul. Badness at /home/paulus/kernel/perf/kernel/hw_breakpoint.c:114 NIP: c0000000000cb470 LR: c0000000000cb46c CTR: c00000000032d9b8 REGS: c000000118e7b570 TRAP: 0700 Not tainted (2.6.35-rc3-perf-00008-g76b0f13 ) MSR: 9000000000029032 <EE,ME,CE,IR,DR> CR: 44004424 XER: 000fffff TASK = c0000001187dcad0[3143] 'perf' THREAD: c000000118e78000 CPU: 1 GPR00: c0000000000cb46c c000000118e7b7f0 c0000000009866a0 0000000000000020 GPR04: 0000000000000000 000000000000001d 0000000000000000 0000000000000001 GPR08: c0000000009bed68 c00000000086dff8 c000000000a5bf10 0000000000000001 GPR12: 0000000024004422 c00000000ffff200 0000000000000000 0000000000000000 GPR16: 0000000000000000 0000000000000000 0000000000000018 00000000101150f4 GPR20: 0000000010206b40 0000000000000000 0000000000000000 00000000101150f4 GPR24: c0000001199090c0 0000000000000001 0000000000000000 0000000000000001 GPR28: 0000000000000000 0000000000000000 c0000000008ec290 0000000000000000 NIP [c0000000000cb470] .task_bp_pinned+0x5c/0x12c LR [c0000000000cb46c] .task_bp_pinned+0x58/0x12c Call Trace: [c000000118e7b7f0] [c0000000000cb46c] .task_bp_pinned+0x58/0x12c (unreliable) [c000000118e7b8a0] [c0000000000cb584] .toggle_bp_task_slot+0x44/0xe4 [c000000118e7b940] [c0000000000cb6c8] .toggle_bp_slot+0xa4/0x164 [c000000118e7b9f0] [c0000000000cbafc] .release_bp_slot+0x44/0x6c [c000000118e7ba80] [c0000000000c4178] .bp_perf_event_destroy+0x10/0x24 [c000000118e7bb00] [c0000000000c4aec] .free_event+0x180/0x1bc [c000000118e7bbc0] [c0000000000c54c4] .perf_event_release_kernel+0x14c/0x170 Reported-by: Paul Mackerras <paulus@samba.org> 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: Prasad <prasad@linux.vnet.ibm.com> Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Jason Wessel <jason.wessel@windriver.com>
* | | | | Merge commit 'v2.6.35-rc3' into perf/coreIngo Molnar2010-06-1811-165/+256
|\ \ \ \ \ | |/ / / / | | | | | | | | | | Merge reason: Go from -rc1 base to -rc3 base, merge in fixes.
| * | | | Merge branch 'perf-fixes-for-linus' of ↵Linus Torvalds2010-06-101-1/+4
| |\ \ \ \ | | |_|/ / | |/| | / | | | |/ | | |/| | | | | | | | | | | | | | | | | | | | | 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: tracing: Fix null pointer deref with SEND_SIG_FORCED perf: Fix signed comparison in perf_adjust_period() powerpc/oprofile: fix potential buffer overrun in op_model_cell.c perf symbols: Set the DSO long name when using symbol_conf.vmlinux_name
| * | | Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linusLinus Torvalds2010-06-042-121/+211
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus: module: fix bne2 "gave up waiting for init of module libcrc32c" module: verify_export_symbols under the lock module: move find_module check to end module: make locking more fine-grained. module: Make module sysfs functions private. module: move sysfs exposure to end of load_module module: fix kdb's illicit use of struct module_use. module: Make the 'usage' lists be two-way
| | * | | module: fix bne2 "gave up waiting for init of module libcrc32c"Rusty Russell2010-06-051-32/+59
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Problem: it's hard to avoid an init routine stumbling over a request_module these days. And it's not clear it's always a bad idea: for example, a module like kvm with dynamic dependencies on kvm-intel or kvm-amd would be neater if it could simply request_module the right one. In this particular case, it's libcrc32c: libcrc32c_mod_init crypto_alloc_shash crypto_alloc_tfm crypto_find_alg crypto_alg_mod_lookup crypto_larval_lookup request_module If another module is waiting inside resolve_symbol() for libcrc32c to finish initializing (ie. bne2 depends on libcrc32c) then it does so holding the module lock, and our request_module() can't make progress until that is released. Waiting inside resolve_symbol() without the lock isn't all that hard: we just need to pass the -EBUSY up the call chain so we can sleep where we don't hold the lock. Error reporting is a bit trickier: we need to copy the name of the unfinished module before releasing the lock. Other notes: 1) This also fixes a theoretical issue where a weak dependency would allow symbol version mismatches to be ignored. 2) We rename use_module to ref_module to make life easier for the only external user (the out-of-tree ksplice patches). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Tim Abbot <tabbott@ksplice.com> Tested-by: Brandon Philips <bphilips@suse.de>
| | * | | module: verify_export_symbols under the lockRusty Russell2010-06-051-16/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It disabled preempt so it was "safe", but nothing stops another module slipping in before this module is added to the global list now we don't hold the lock the whole time. So we check this just after we check for duplicate modules, and just before we put the module in the global list. (find_symbol finds symbols in coming and going modules, too). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
generated by cgit v1.1 at 2024-12-26 06:36:21 +0000