- 08 11月, 2011 6 次提交
-
-
由 Dominik Brodowski 提交于
Since commit 4a31a334, the name of this misc device is not initialized, which leads to a funny device named /dev/(null) being created and /proc/misc containing an entry with just a number but no name. The latter leads to complaints by cryptsetup, which caused me to investigate this matter. Signed-off-by: NDominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
-
由 Jiri Olsa 提交于
In case the the graph tracer (CONFIG_FUNCTION_GRAPH_TRACER) or even the function tracer (CONFIG_FUNCTION_TRACER) are not set, the latency tracers do not display proper latency header. The involved/fixed latency tracers are: wakeup_rt wakeup preemptirqsoff preemptoff irqsoff The patch adds proper handling of tracer configuration options for latency tracers, and displaying correct header info accordingly. * The current output (for wakeup tracer) with both graph and function tracers disabled is: # tracer: wakeup # <idle>-0 0d.h5 1us+: 0:120:R + [000] 7: 0:R watchdog/0 <idle>-0 0d.h5 3us+: ttwu_do_activate.clone.1 <-try_to_wake_up ... * The fixed output is: # tracer: wakeup # # wakeup latency trace v1.1.5 on 3.1.0-tip+ # -------------------------------------------------------------------- # latency: 55 us, #4/4, CPU#0 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:2) # ----------------- # | task: migration/0-6 (uid:0 nice:0 policy:1 rt_prio:99) # ----------------- # # _------=> CPU# # / _-----=> irqs-off # | / _----=> need-resched # || / _---=> hardirq/softirq # ||| / _--=> preempt-depth # |||| / delay # cmd pid ||||| time | caller # \ / ||||| \ | / cat-1129 0d..4 1us : 1129:120:R + [000] 6: 0:R migration/0 cat-1129 0d..4 2us+: ttwu_do_activate.clone.1 <-try_to_wake_up * The current output (for wakeup tracer) with only function tracer enabled is: # tracer: wakeup # cat-1140 0d..4 1us+: 1140:120:R + [000] 6: 0:R migration/0 cat-1140 0d..4 2us : ttwu_do_activate.clone.1 <-try_to_wake_up * The fixed output is: # tracer: wakeup # # wakeup latency trace v1.1.5 on 3.1.0-tip+ # -------------------------------------------------------------------- # latency: 207 us, #109/109, CPU#1 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:2) # ----------------- # | task: watchdog/1-12 (uid:0 nice:0 policy:1 rt_prio:99) # ----------------- # # _------=> CPU# # / _-----=> irqs-off # | / _----=> need-resched # || / _---=> hardirq/softirq # ||| / _--=> preempt-depth # |||| / delay # cmd pid ||||| time | caller # \ / ||||| \ | / <idle>-0 1d.h5 1us+: 0:120:R + [001] 12: 0:R watchdog/1 <idle>-0 1d.h5 3us : ttwu_do_activate.clone.1 <-try_to_wake_up Link: http://lkml.kernel.org/r/20111107150849.GE1807@m.brq.redhat.com Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: NJiri Olsa <jolsa@redhat.com> Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
-
由 Steven Rostedt 提交于
If the set_ftrace_filter is cleared by writing just whitespace to it, then the filter hash refcounts will be decremented but not updated. This causes two bugs: 1) No functions will be enabled for tracing when they all should be 2) If the users clears the set_ftrace_filter twice, it will crash ftrace: ------------[ cut here ]------------ WARNING: at /home/rostedt/work/git/linux-trace.git/kernel/trace/ftrace.c:1384 __ftrace_hash_rec_update.part.27+0x157/0x1a7() Modules linked in: Pid: 2330, comm: bash Not tainted 3.1.0-test+ #32 Call Trace: [<ffffffff81051828>] warn_slowpath_common+0x83/0x9b [<ffffffff8105185a>] warn_slowpath_null+0x1a/0x1c [<ffffffff810ba362>] __ftrace_hash_rec_update.part.27+0x157/0x1a7 [<ffffffff810ba6e8>] ? ftrace_regex_release+0xa7/0x10f [<ffffffff8111bdfe>] ? kfree+0xe5/0x115 [<ffffffff810ba51e>] ftrace_hash_move+0x2e/0x151 [<ffffffff810ba6fb>] ftrace_regex_release+0xba/0x10f [<ffffffff8112e49a>] fput+0xfd/0x1c2 [<ffffffff8112b54c>] filp_close+0x6d/0x78 [<ffffffff8113a92d>] sys_dup3+0x197/0x1c1 [<ffffffff8113a9a6>] sys_dup2+0x4f/0x54 [<ffffffff8150cac2>] system_call_fastpath+0x16/0x1b ---[ end trace 77a3a7ee73794a02 ]--- Link: http://lkml.kernel.org/r/20111101141420.GA4918@debianReported-by: NRabin Vincent <rabin@rab.in> Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
-
由 Gleb Natapov 提交于
If cpu A calls jump_label_inc() just after atomic_add_return() is called by cpu B, atomic_inc_not_zero() will return value greater then zero and jump_label_inc() will return to a caller before jump_label_update() finishes its job on cpu B. Link: http://lkml.kernel.org/r/20111018175551.GH17571@redhat.com Cc: stable@vger.kernel.org Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: NJason Baron <jbaron@redhat.com> Signed-off-by: NGleb Natapov <gleb@redhat.com> Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
-
由 Steven Rostedt 提交于
A forced undef of a config value was used for testing and was accidently left in during the final commit. This causes x86 to run slower than needed while running function tracing as well as causes the function graph selftest to fail when DYNMAIC_FTRACE is not set. This is because the code in MCOUNT expects the ftrace code to be processed with the config value set that happened to be forced not set. The forced config option was left in by: commit 6331c28c ftrace: Fix dynamic selftest failure on some archs Link: http://lkml.kernel.org/r/20111102150255.GA6973@debian Cc: stable@vger.kernel.org Reported-by: NRabin Vincent <rabin@rab.in> Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
-
由 Steven Rostedt 提交于
The pretty print of the lockdep debug splat uses just the lock name to show how the locking scenario happens. But when it comes to nesting locks, the output becomes confusing which takes away the point of the pretty printing of the lock scenario. Without displaying the subclass info, we get the following output: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(slock-AF_INET); lock(slock-AF_INET); lock(slock-AF_INET); lock(slock-AF_INET); *** DEADLOCK *** The above looks more of a A->A locking bug than a A->B B->A. By adding the subclass to the output, we can see what really happened: other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(slock-AF_INET); lock(slock-AF_INET/1); lock(slock-AF_INET); lock(slock-AF_INET/1); *** DEADLOCK *** This bug was discovered while tracking down a real bug caught by lockdep. Link: http://lkml.kernel.org/r/20111025202049.GB25043@hostway.ca Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Reported-by: NThomas Gleixner <tglx@linutronix.de> Tested-by: NSimon Kirby <sim@hostway.ca> Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
-
- 07 11月, 2011 2 次提交
-
-
由 Ben Hutchings 提交于
Use of the GPL or a compatible licence doesn't necessarily make the code any good. We already consider staging modules to be suspect, and this should also be true for out-of-tree modules which may receive very little review. Signed-off-by: NBen Hutchings <ben@decadent.org.uk> Reviewed-by: NDave Jones <davej@redhat.com> Acked-by: NGreg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (patched oops-tracing.txt)
-
由 Ben Hutchings 提交于
Dynamic debugging is currently disabled for tainted modules, except for TAINT_CRAP. This prevents use of dynamic debugging for out-of-tree modules once the next patch is applied. This condition was apparently intended to avoid a crash if a force- loaded module has an incompatible definition of dynamic debug structures. However, a administrator that forces us to load a module is claiming that it *is* compatible even though it fails our version checks. If they are mistaken, there are any number of ways the module could crash the system. As a side-effect, proprietary and other tainted modules can now use dynamic_debug. Signed-off-by: NBen Hutchings <ben@decadent.org.uk> Acked-by: NMathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
-
- 05 11月, 2011 4 次提交
-
-
由 Steven Rostedt 提交于
The system filter can be used to set multiple event filters that exist within the system. But currently it displays the last filter written that does not necessarily correspond to the filters within the system. The system filter itself is not used to filter any events. The system filter is just a means to set filters of the events within it. Because this causes an ambiguous state when the system filter reads a filter string but the events within the system have different strings it is best to just show a boiler plate: ### global filter ### # Use this to set filters for multiple events. # Only events with the given fields will be affected. # If no events are modified, an error message will be displayed here. If an error occurs while writing to the system filter, the system filter will replace the boiler plate with the error message as it currently does. Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
-
由 Tejun Heo 提交于
PM / Freezer: Revert 27920651 "PM / Freezer: Make fake_signal_wake_up() wake TASK_KILLABLE tasks too" Commit 27920651 "PM / Freezer: Make fake_signal_wake_up() wake TASK_KILLABLE tasks too" updated fake_signal_wake_up() used by freezer to wake up KILLABLE tasks. Sending unsolicited wakeups to tasks in killable sleep is dangerous as there are code paths which depend on tasks not waking up spuriously from KILLABLE sleep. For example. sys_read() or page can sleep in TASK_KILLABLE assuming that wait/down/whatever _killable can only fail if we can not return to the usermode. TASK_TRACED is another obvious example. The previous patch updated wait_event_freezekillable() such that it doesn't depend on the spurious wakeup. This patch reverts the offending commit. Note that the spurious KILLABLE wakeup had other implicit effects in KILLABLE sleeps in nfs and cifs and those will need further updates to regain freezekillable behavior. Signed-off-by: NTejun Heo <tj@kernel.org> Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
-
由 Guennadi Liakhovetski 提交于
Remove an "if" check, that repeats an equivalent one 6 lines above. Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
-
由 Srivatsa S. Bhat 提交于
The CPU hotplug notifications sent out by the _cpu_up() and _cpu_down() functions depend on the value of the 'tasks_frozen' argument passed to them (which indicates whether tasks have been frozen or not). (Examples for such CPU hotplug notifications: CPU_ONLINE, CPU_ONLINE_FROZEN, CPU_DEAD, CPU_DEAD_FROZEN). Thus, it is essential that while the callbacks for those notifications are running, the state of the system with respect to the tasks being frozen or not remains unchanged, *throughout that duration*. Hence there is a need for synchronizing the CPU hotplug code with the freezer subsystem. Since the freezer is involved only in the Suspend/Hibernate call paths, this patch hooks the CPU hotplug code to the suspend/hibernate notifiers PM_[SUSPEND|HIBERNATE]_PREPARE and PM_POST_[SUSPEND|HIBERNATE] to prevent the race between CPU hotplug and freezer, thus ensuring that CPU hotplug notifications will always be run with the state of the system really being what the notifications indicate, _throughout_ their execution time. Signed-off-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
-
- 03 11月, 2011 7 次提交
-
-
由 Linus Torvalds 提交于
This reverts commit 144060fe. It causes a resume regression for Andi on his Acer Aspire 1830T post 3.1. The screen just stays black after wakeup. Also, it really looks like the wrong way to suspend and resume perf events: I think they should be done as part of the CPU suspend and resume, rather than as a notifier that does smp_call_function(). Reported-by: NAndi Kleen <andi@firstfloor.org> Acked-by: NIngo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Andrew Bresticker 提交于
While back-porting Johannes Weiner's patch "mm: memcg-aware global reclaim" for an internal effort, we noticed a significant performance regression during page-reclaim heavy workloads due to high contention of the ss->id_lock. This lock protects idr map, and serializes calls to idr_get_next() in css_get_next() (which is used during the memcg hierarchy walk). Since idr_get_next() is just doing a look up, we need only serialize it with respect to idr_remove()/idr_get_new(). By making the ss->id_lock a rwlock, contention is greatly reduced and performance improves. Tested: cat a 256m file from a ramdisk in a 128m container 50 times on each core (one file + container per core) in parallel on a NUMA machine. Result is the time for the test to complete in 1 of the containers. Both kernels included Johannes' memcg-aware global reclaim patches. Before rwlock patch: 1710.778s After rwlock patch: 152.227s Signed-off-by: NAndrew Bresticker <abrestic@google.com> Cc: Paul Menage <menage@gmail.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Acked-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Ying Han <yinghan@google.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Lucas De Marchi 提交于
Adding support for poll() in sysctl fs allows userspace to receive notifications of changes in sysctl entries. This adds a infrastructure to allow files in sysctl fs to be pollable and implements it for hostname and domainname. [akpm@linux-foundation.org: s/declare/define/ for definitions] Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi> Cc: Greg KH <gregkh@suse.de> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 David Rientjes 提交于
{get,put}_mems_allowed() exist so that general kernel code may locklessly access a task's set of allowable nodes without having the chance that a concurrent write will cause the nodemask to be empty on configurations where MAX_NUMNODES > BITS_PER_LONG. This could incur a significant delay, however, especially in low memory conditions because the page allocator is blocking and reclaim requires get_mems_allowed() itself. It is not atypical to see writes to cpuset.mems take over 2 seconds to complete, for example. In low memory conditions, this is problematic because it's one of the most imporant times to change cpuset.mems in the first place! The only way a task's set of allowable nodes may change is through cpusets by writing to cpuset.mems and when attaching a task to a generic code is not reading the nodemask with get_mems_allowed() at the same time, and then clearing all the old nodes. This prevents the possibility that a reader will see an empty nodemask at the same time the writer is storing a new nodemask. If at least one node remains unchanged, though, it's possible to simply set all new nodes and then clear all the old nodes. Changing a task's nodemask is protected by cgroup_mutex so it's guaranteed that two threads are not changing the same task's nodemask at the same time, so the nodemask is guaranteed to be stored before another thread changes it and determines whether a node remains set or not. Signed-off-by: NDavid Rientjes <rientjes@google.com> Cc: Miao Xie <miaox@cn.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Paul Menage <paul@paulmenage.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Ben Blum 提交于
If a task has exited to the point it has called cgroup_exit() already, then we can't migrate it to another cgroup anymore. This can happen when we are attaching a task to a new cgroup between the call to ->can_attach_task() on subsystems and the migration that is eventually tried in cgroup_task_migrate(). In this case cgroup_task_migrate() returns -ESRCH and we don't want to attach the task to the subsystems because the attachment to the new cgroup itself failed. Fix this by only calling ->attach_task() on the subsystems if the cgroup migration succeeded. Reported-by: NOleg Nesterov <oleg@redhat.com> Signed-off-by: NBen Blum <bblum@andrew.cmu.edu> Acked-by: NPaul Menage <paul@paulmenage.org> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Ben Blum 提交于
Fix unstable tasklist locking in cgroup_attach_proc. According to this thread - https://lkml.org/lkml/2011/7/27/243 - RCU is not sufficient to guarantee the tasklist is stable w.r.t. de_thread and exit. Taking tasklist_lock for reading, instead of rcu_read_lock, ensures proper exclusion. Signed-off-by: NBen Blum <bblum@andrew.cmu.edu> Acked-by: NPaul Menage <paul@paulmenage.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Neil Brown <neilb@suse.de> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Li Zefan 提交于
Though not all events have field 'prev_pid', it was allowed to do this: # echo 'prev_pid == 100' > events/sched/filter but commit 75b8e982 (tracing/filter: Swap entire filter of events) broke it without any reason. Link: http://lkml.kernel.org/r/4EAF46CF.8040408@cn.fujitsu.comSigned-off-by: NLi Zefan <lizf@cn.fujitsu.com> Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
-
- 01 11月, 2011 14 次提交
-
-
由 Andy Shevchenko 提交于
There is no functional change. Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: NJesper Nilsson <jesper.nilsson@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 William Douglas 提交于
Currently log_prefix is testing that the first character of the log level and facility is less than '0' and greater than '9' (which is always false). Since the code being updated works because strtoul bombs out (endp isn't updated) and 0 is returned anyway just remove the check and don't change the behavior of the function. Signed-off-by: NWilliam Douglas <william.douglas@intel.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 William Douglas 提交于
Currently log_prefix is testing that the first character of the log level and facility is less than '0' and greater than '9' (which is always false). It should be testing to see if the character less than '0' or greater than '9' instead. This patch makes that change. The code being changed worked because strtoul bombs out (endp isn't updated) and 0 is returned anyway. Signed-off-by: NWilliam Douglas <william.douglas@intel.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Yanmin Zhang 提交于
We are enabling some power features on medfield. To test suspend-2-RAM conveniently, we need turn on/off console_suspend_enabled frequently. Add a module parameter, so users could change it by: /sys/module/printk/parameters/console_suspend Signed-off-by: NYanmin Zhang <yanmin_zhang@linux.intel.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Yanmin Zhang 提交于
We are enabling some power features on medfield. To test suspend-2-RAM conveniently, we need turn on/off ignore_loglevel frequently without rebooting. Add a module parameter, so users can change it by: /sys/module/printk/parameters/ignore_loglevel Signed-off-by: NYanmin Zhang <yanmin.zhang@intel.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Dan Ballard 提交于
Userspace needs to know the highest valid capability of the running kernel, which right now cannot reliably be retrieved from the header files only. The fact that this value cannot be determined properly right now creates various problems for libraries compiled on newer header files which are run on older kernels. They assume capabilities are available which actually aren't. libcap-ng is one example. And we ran into the same problem with systemd too. Now the capability is exported in /proc/sys/kernel/cap_last_cap. [akpm@linux-foundation.org: make cap_last_cap const, per Ulrich] Signed-off-by: NDan Ballard <dan@mindstab.net> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Ingo Molnar <mingo@elte.hu> Cc: Lennart Poettering <lennart@poettering.net> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Ulrich Drepper <drepper@akkadia.org> Cc: James Morris <jmorris@namei.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Vasily Averin 提交于
Fix compilation warnings for CONFIG_SYSCTL=n: fixed compilation warnings in case of disabled CONFIG_SYSCTL kernel/watchdog.c:483:13: warning: `watchdog_enable_all_cpus' defined but not used kernel/watchdog.c:500:13: warning: `watchdog_disable_all_cpus' defined but not used these functions are static and are used only in sysctl handler, so move them inside #ifdef CONFIG_SYSCTL too Signed-off-by: NVasily Averin <vvs@sw.ru> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Jeremy Fitzhardinge 提交于
Make stop_machine() safe to call early in boot, before SMP has been set up, by simply calling the callback function directly if there's only one CPU online. [ Fixes from AKPM: - add comment - local_irq_flags, not save_flags - also call hard_irq_disable() for systems which need it Tejun suggested using an explicit flag rather than just looking at the online cpu count. ] Cc: Tejun Heo <tj@kernel.org> Acked-by: NRusty Russell <rusty@rustcorp.com.au> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Steven Rostedt <rostedt@goodmis.org> Acked-by: NTejun Heo <htejun@gmail.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Christoph Lameter 提交于
Some kernel components pin user space memory (infiniband and perf) (by increasing the page count) and account that memory as "mlocked". The difference between mlocking and pinning is: A. mlocked pages are marked with PG_mlocked and are exempt from swapping. Page migration may move them around though. They are kept on a special LRU list. B. Pinned pages cannot be moved because something needs to directly access physical memory. They may not be on any LRU list. I recently saw an mlockalled process where mm->locked_vm became bigger than the virtual size of the process (!) because some memory was accounted for twice: Once when the page was mlocked and once when the Infiniband layer increased the refcount because it needt to pin the RDMA memory. This patch introduces a separate counter for pinned pages and accounts them seperately. Signed-off-by: NChristoph Lameter <cl@linux.com> Cc: Mike Marciniszyn <infinipath@qlogic.com> Cc: Roland Dreier <roland@kernel.org> Cc: Sean Hefty <sean.hefty@intel.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 David Rientjes 提交于
This removes mm->oom_disable_count entirely since it's unnecessary and currently buggy. The counter was intended to be per-process but it's currently decremented in the exit path for each thread that exits, causing it to underflow. The count was originally intended to prevent oom killing threads that share memory with threads that cannot be killed since it doesn't lead to future memory freeing. The counter could be fixed to represent all threads sharing the same mm, but it's better to remove the count since: - it is possible that the OOM_DISABLE thread sharing memory with the victim is waiting on that thread to exit and will actually cause future memory freeing, and - there is no guarantee that a thread is disabled from oom killing just because another thread sharing its mm is oom disabled. Signed-off-by: NDavid Rientjes <rientjes@google.com> Reported-by: NOleg Nesterov <oleg@redhat.com> Reviewed-by: NOleg Nesterov <oleg@redhat.com> Cc: Ying Han <yinghan@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Christopher Yeoh 提交于
The basic idea behind cross memory attach is to allow MPI programs doing intra-node communication to do a single copy of the message rather than a double copy of the message via shared memory. The following patch attempts to achieve this by allowing a destination process, given an address and size from a source process, to copy memory directly from the source process into its own address space via a system call. There is also a symmetrical ability to copy from the current process's address space into a destination process's address space. - Use of /proc/pid/mem has been considered, but there are issues with using it: - Does not allow for specifying iovecs for both src and dest, assuming preadv or pwritev was implemented either the area read from or written to would need to be contiguous. - Currently mem_read allows only processes who are currently ptrace'ing the target and are still able to ptrace the target to read from the target. This check could possibly be moved to the open call, but its not clear exactly what race this restriction is stopping (reason appears to have been lost) - Having to send the fd of /proc/self/mem via SCM_RIGHTS on unix domain socket is a bit ugly from a userspace point of view, especially when you may have hundreds if not (eventually) thousands of processes that all need to do this with each other - Doesn't allow for some future use of the interface we would like to consider adding in the future (see below) - Interestingly reading from /proc/pid/mem currently actually involves two copies! (But this could be fixed pretty easily) As mentioned previously use of vmsplice instead was considered, but has problems. Since you need the reader and writer working co-operatively if the pipe is not drained then you block. Which requires some wrapping to do non blocking on the send side or polling on the receive. In all to all communication it requires ordering otherwise you can deadlock. And in the example of many MPI tasks writing to one MPI task vmsplice serialises the copying. There are some cases of MPI collectives where even a single copy interface does not get us the performance gain we could. For example in an MPI_Reduce rather than copy the data from the source we would like to instead use it directly in a mathops (say the reduce is doing a sum) as this would save us doing a copy. We don't need to keep a copy of the data from the source. I haven't implemented this, but I think this interface could in the future do all this through the use of the flags - eg could specify the math operation and type and the kernel rather than just copying the data would apply the specified operation between the source and destination and store it in the destination. Although we don't have a "second user" of the interface (though I've had some nibbles from people who may be interested in using it for intra process messaging which is not MPI). This interface is something which hardware vendors are already doing for their custom drivers to implement fast local communication. And so in addition to this being useful for OpenMPI it would mean the driver maintainers don't have to fix things up when the mm changes. There was some discussion about how much faster a true zero copy would go. Here's a link back to the email with some testing I did on that: http://marc.info/?l=linux-mm&m=130105930902915&w=2 There is a basic man page for the proposed interface here: http://ozlabs.org/~cyeoh/cma/process_vm_readv.txt This has been implemented for x86 and powerpc, other architecture should mainly (I think) just need to add syscall numbers for the process_vm_readv and process_vm_writev. There are 32 bit compatibility versions for 64-bit kernels. For arch maintainers there are some simple tests to be able to quickly verify that the syscalls are working correctly here: http://ozlabs.org/~cyeoh/cma/cma-test-20110718.tgzSigned-off-by: NChris Yeoh <yeohc@au1.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: David Howells <dhowells@redhat.com> Cc: James Morris <jmorris@namei.org> Cc: <linux-man@vger.kernel.org> Cc: <linux-arch@vger.kernel.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Paul Gortmaker 提交于
Recent commit "irq: Track the owner of irq descriptor" in commit ID b6873807 placed module.h into linux/irq.h but we are trying to limit module.h inclusion to just C files that really need it, due to its size and number of children includes. This targets just reversing that include. Add in the basic "struct module" since that is all we really need to ensure things compile. In theory, b6873807 should have added the module.h include to the irqdesc.h header as well, but the implicit module.h everywhere presence masked this from showing up. So give it the "struct module" as well. As for the C files, irqdesc.c is only using THIS_MODULE, so it does not need module.h - give it export.h instead. The C file irq/manage.c is now (as of b6873807) using try_module_get and module_put and so it needs module.h (which it already has). Also convert the irq_alloc_descs variants to macros, since all they really do is is call the __irq_alloc_descs primitive. This avoids including export.h and no debug info is lost. Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
-
由 Paul Gortmaker 提交于
These files were getting <linux/module.h> via an implicit non-obvious path, but we want to crush those out of existence since they cost time during compiles of processing thousands of lines of headers for no reason. Give them the lightweight header that just contains the EXPORT_SYMBOL infrastructure. Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
-
由 Ilya Dryomov 提交于
Fix a bug introduced by e9dbfae5, which prevents event_subsystem from ever being released. Ref_count was added to keep track of subsystem users, not for counting events. Subsystem is created with ref_count = 1, so there is no need to increment it for every event, we have nr_events for that. Fix this by touching ref_count only when we actually have a new user - subsystem_open(). Cc: stable@vger.kernel.org Signed-off-by: NIlya Dryomov <idryomov@gmail.com> Link: http://lkml.kernel.org/r/1320052062-7846-1-git-send-email-idryomov@gmail.comSigned-off-by: NSteven Rostedt <rostedt@goodmis.org>
-
- 31 10月, 2011 7 次提交
-
-
由 Paul Gortmaker 提交于
The file rcutiny.c does not need moduleparam.h header, as there are no modparams in this file. However rcutiny_plugin.h does define a module_init() and a module_exit() and it uses the various MODULE_ macros, so it really does need module.h included. Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
-
由 Paul Gortmaker 提交于
Through various other implicit include paths, some files were getting the full module.h file, and hence living the illusion that they really only needed moduleparam.h -- but the reality is that once you remove the module.h presence, these show up: kernel/params.c:583: warning: ‘struct module_kobject’ declared inside parameter list Such files really require module.h so simply make it so. As the file module.h grabs moduleparam.h on the fly, all will be well. Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
-
由 Paul Gortmaker 提交于
With the module.h usage cleanup, we'll get this: kernel/ksysfs.c:161: error: ‘S_IRUGO’ undeclared here (not in a function) make[2]: *** [kernel/ksysfs.o] Error 1 Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
-
由 Paul Gortmaker 提交于
Up until now, this file was getting percpu.h because nearly every file was implicitly getting module.h (and all its sub-includes). But we want to clean that up, so call out percpu.h explicitly. Otherwise we'll get things like this on an ARM build: kernel/irq_work.c:48: error: expected declaration specifiers or '...' before 'irq_work_list' kernel/irq_work.c:48: warning: type defaults to 'int' in declaration of 'DEFINE_PER_CPU' The same thing was happening for builds on ARM for asm/processor.h kernel/irq_work.c: In function 'irq_work_sync': kernel/irq_work.c:166: error: implicit declaration of function 'cpu_relax' Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
-
由 Paul Gortmaker 提交于
These files were implicitly relying on <linux/kmod.h> coming in via module.h, as without it we get things like: kernel/power/suspend.c:100: error: implicit declaration of function ‘usermodehelper_disable’ kernel/power/suspend.c:109: error: implicit declaration of function ‘usermodehelper_enable’ kernel/power/user.c:254: error: implicit declaration of function ‘usermodehelper_disable’ kernel/power/user.c:261: error: implicit declaration of function ‘usermodehelper_enable’ kernel/sys.c:317: error: implicit declaration of function ‘usermodehelper_disable’ kernel/sys.c:1816: error: implicit declaration of function ‘call_usermodehelper_setup’ kernel/sys.c:1822: error: implicit declaration of function ‘call_usermodehelper_setfns’ kernel/sys.c:1824: error: implicit declaration of function ‘call_usermodehelper_exec’ Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
-
由 Paul Gortmaker 提交于
These files are doing things like module_put and try_module_get so they need to call out the module.h for explicit inclusion, rather than getting it via <linux/device.h> which we ideally want to remove the module.h inclusion from. Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
-
由 Paul Gortmaker 提交于
The changed files were only including linux/module.h for the EXPORT_SYMBOL infrastructure, and nothing else. Revector them onto the isolated export header for faster compile times. Nothing to see here but a whole lot of instances of: -#include <linux/module.h> +#include <linux/export.h> This commit is only changing the kernel dir; next targets will probably be mm, fs, the arch dirs, etc. Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
-