Cross Reference: /arch/x86/kernel/process

History log of /arch/x86/kernel/process_32.c
Revision	Date	Author	Comments
f05e798ad4c09255f590f5b2c00a7ca6c172f983	28-Mar-2012	David Howells <dhowells@redhat.com>	Disintegrate asm/system.h for X86 Disintegrate asm/system.h for X86. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: H. Peter Anvin <hpa@zytor.com> cc: x86@kernel.org
90e240142bd31ff10aeda5a280a53153f4eff004	25-Mar-2012	Richard Weinberger <richard@nod.at>	x86: Merge the x86_32 and x86_64 cpu_idle() functions Both functions are mostly identical. The differences are: - x86_32's cpu_idle() makes use of check_pgt_cache(), which is a nop on both x86_32 and x86_64. - x86_64's cpu_idle() uses enter/__exit_idle/(), on x86_32 these function are a nop. - In contrast to x86_32, x86_64 calls rcu_idle_enter/exit() in the innermost loop because idle notifications need RCU. Calling these function on x86_32 also in the innermost loop does not hurt. So we can merge both functions. Signed-off-by: Richard Weinberger <richard@nod.at> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: paulmck@linux.vnet.ibm.com Cc: josh@joshtriplett.org Cc: tj@kernel.org Link: http://lkml.kernel.org/r/1332709204-22496-1-git-send-email-richard@nod.at Signed-off-by: Ingo Molnar <mingo@kernel.org>
bd2f55361f18347e890d52ff9cfd8895455ec11b	21-Mar-2011	Thomas Gleixner <tglx@linutronix.de>	sched/rt: Use schedule_preempt_disabled() Coccinelle based conversion. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/n/tip-24swm5zut3h9c4a6s46x8rws@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
1361b83a13d4d92e53fbb6c877528713e118b821	21-Feb-2012	Linus Torvalds <torvalds@linux-foundation.org>	i387: Split up <asm/i387.h> into exported and internal interfaces While various modules include <asm/i387.h> to get access to things we actually intend for them to use, most of that header file was really pretty low-level internal stuff that we really don't want to expose to others. So split the header file into two: the small exported interfaces remain in <asm/i387.h>, while the internal definitions that are only used by core architecture code are now in <asm/fpu-internal.h>. The guiding principle for this was to expose functions that we export to modules, and leave them in <asm/i387.h>, while stuff that is used by task switching or was marked GPL-only is in <asm/fpu-internal.h>. The fpu-internal.h file could be further split up too, especially since arch/x86/kvm/ uses some of the remaining stuff for its module. But that kvm usage should probably be abstracted out a bit, and at least now the internal FPU accessor functions are much more contained. Even if it isn't perhaps as contained as it _could_ be. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1202211340330.5354@i5.linux-foundation.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
7e16838d94b566a17b65231073d179bc04d590c8	19-Feb-2012	Linus Torvalds <torvalds@linux-foundation.org>	i387: support lazy restore of FPU state This makes us recognize when we try to restore FPU state that matches what we already have in the FPU on this CPU, and avoids the restore entirely if so. To do this, we add two new data fields: - a percpu 'fpu_owner_task' variable that gets written any time we update the "has_fpu" field, and thus acts as a kind of back-pointer to the task that owns the CPU. The exception is when we save the FPU state as part of a context switch - if the save can keep the FPU state around, we leave the 'fpu_owner_task' variable pointing at the task whose FP state still remains on the CPU. - a per-thread 'last_cpu' field, that indicates which CPU that thread used its FPU on last. We update this on every context switch (writing an invalid CPU number if the last context switch didn't leave the FPU in a lazily usable state), so we know that that thread has done nothing else with the FPU since. These two fields together can be used when next switching back to the task to see if the CPU still matches: if 'fpu_owner_task' matches the task we are switching to, we know that no other task (or kernel FPU usage) touched the FPU on this CPU in the meantime, and if the current CPU number matches the 'last_cpu' field, we know that this thread did no other FP work on any other CPU, so the FPU state on the CPU must match what was saved on last context switch. In that case, we can avoid the 'f[x]rstor' entirely, and just clear the CR0.TS bit. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
cea20ca3f3181fc36788a15bc65d1062b96a0a6c	20-Feb-2012	Linus Torvalds <torvalds@linux-foundation.org>	i387: fix up some fpu_counter confusion This makes sure we clear the FPU usage counter for newly created tasks, just so that we start off in a known state (for example, don't try to preload the FPU state on the first task switch etc). It also fixes a thinko in when we increment the fpu_counter at task switch time, introduced by commit 34ddc81a230b ("i387: re-introduce FPU state preloading at context switch time"). We should increment the new task fpu_counter, not the old task, and only if we decide to use that state (whether lazily or preloaded). Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
34ddc81a230b15c0e345b6b253049db731499f7e	18-Feb-2012	Linus Torvalds <torvalds@linux-foundation.org>	i387: re-introduce FPU state preloading at context switch time After all the FPU state cleanups and finally finding the problem that caused all our FPU save/restore problems, this re-introduces the preloading of FPU state that was removed in commit b3b0870ef3ff ("i387: do not preload FPU state at task switch time"). However, instead of simply reverting the removal, this reimplements preloading with several fixes, most notably - properly abstracted as a true FPU state switch, rather than as open-coded save and restore with various hacks. In particular, implementing it as a proper FPU state switch allows us to optimize the CR0.TS flag accesses: there is no reason to set the TS bit only to then almost immediately clear it again. CR0 accesses are quite slow and expensive, don't flip the bit back and forth for no good reason. - Make sure that the same model works for both x86-32 and x86-64, so that there are no gratuitous differences between the two due to the way they save and restore segment state differently due to architectural differences that really don't matter to the FPU state. - Avoid exposing the "preload" state to the context switch routines, and in particular allow the concept of lazy state restore: if nothing else has used the FPU in the meantime, and the process is still on the same CPU, we can avoid restoring state from memory entirely, just re-expose the state that is still in the FPU unit. That optimized lazy restore isn't actually implemented here, but the infrastructure is set up for it. Of course, older CPU's that use 'fnsave' to save the state cannot take advantage of this, since the state saving also trashes the state. In other words, there is now an actual _design_ to the FPU state saving, rather than just random historical baggage. Hopefully it's easier to follow as a result. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
b3b0870ef3ffed72b92415423da864f440f57ad6	17-Feb-2012	Linus Torvalds <torvalds@linux-foundation.org>	i387: do not preload FPU state at task switch time Yes, taking the trap to re-load the FPU/MMX state is expensive, but so is spending several days looking for a bug in the state save/restore code. And the preload code has some rather subtle interactions with both paravirtualization support and segment state restore, so it's not nearly as simple as it should be. Also, now that we no longer necessarily depend on a single bit (ie TS_USEDFPU) for keeping track of the state of the FPU, we migth be able to do better. If we are really switching between two processes that keep touching the FP state, save/restore is inevitable, but in the case of having one process that does most of the FPU usage, we may actually be able to do much better than the preloading. In particular, we may be able to keep track of which CPU the process ran on last, and also per CPU keep track of which process' FP state that CPU has. For modern CPU's that don't destroy the FPU contents on save time, that would allow us to do a lazy restore by just re-enabling the existing FPU state - with no restore cost at all! Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1268fbc746ea1cd279886a740dcbad4ba5232225	17-Nov-2011	Frederic Weisbecker <fweisbec@gmail.com>	nohz: Remove tick_nohz_idle_enter_norcu() / tick_nohz_idle_exit_norcu() Those two APIs were provided to optimize the calls of tick_nohz_idle_enter() and rcu_idle_enter() into a single irq disabled section. This way no interrupt happening in-between would needlessly process any RCU job. Now we are talking about an optimization for which benefits have yet to be measured. Let's start simple and completely decouple idle rcu and dyntick idle logics to simplify. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2bbb6817c0ac1b5f2a68d720f364f98eeb1ac4fd	08-Oct-2011	Frederic Weisbecker <fweisbec@gmail.com>	nohz: Allow rcu extended quiescent state handling seperately from tick stop It is assumed that rcu won't be used once we switch to tickless mode and until we restart the tick. However this is not always true, as in x86-64 where we dereference the idle notifiers after the tick is stopped. To prepare for fixing this, add two new APIs: tick_nohz_idle_enter_norcu() and tick_nohz_idle_exit_norcu(). If no use of RCU is made in the idle loop between tick_nohz_enter_idle() and tick_nohz_exit_idle() calls, the arch must instead call the new *_norcu() version such that the arch doesn't need to call rcu_idle_enter() and rcu_idle_exit(). Otherwise the arch must call tick_nohz_enter_idle() and tick_nohz_exit_idle() and also call explicitly: - rcu_idle_enter() after its last use of RCU before the CPU is put to sleep. - rcu_idle_exit() before the first use of RCU after the CPU is woken up. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: David Miller <davem@davemloft.net> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Paul Mackerras <paulus@samba.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
280f06774afedf849f0b34248ed6aff57d0f6908	07-Oct-2011	Frederic Weisbecker <fweisbec@gmail.com>	nohz: Separate out irq exit and idle loop dyntick logic The tick_nohz_stop_sched_tick() function, which tries to delay the next timer tick as long as possible, can be called from two places: - From the idle loop to start the dytick idle mode - From interrupt exit if we have interrupted the dyntick idle mode, so that we reprogram the next tick event in case the irq changed some internal state that requires this action. There are only few minor differences between both that are handled by that function, driven by the ts->inidle cpu variable and the inidle parameter. The whole guarantees that we only update the dyntick mode on irq exit if we actually interrupted the dyntick idle mode, and that we enter in RCU extended quiescent state from idle loop entry only. Split this function into: - tick_nohz_idle_enter(), which sets ts->inidle to 1, enters dynticks idle mode unconditionally if it can, and enters into RCU extended quiescent state. - tick_nohz_irq_exit() which only updates the dynticks idle mode when ts->inidle is set (ie: if tick_nohz_idle_enter() has been called). To maintain symmetry, tick_nohz_restart_sched_tick() has been renamed into tick_nohz_idle_exit(). This simplifies the code and micro-optimize the irq exit path (no need for local_irq_save there). This also prepares for the split between dynticks and rcu extended quiescent state logics. We'll need this split to further fix illegal uses of RCU in extended quiescent states in the idle loop. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: David Miller <davem@davemloft.net> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Paul Mackerras <paulus@samba.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
b227e23399dc59977aa42c49bd668bdab7a61812	30-Sep-2011	Don Zickus <dzickus@redhat.com>	x86, nmi: Add in logic to handle multiple events and unknown NMIs Previous patches allow the NMI subsystem to process multipe NMI events in one NMI. As previously discussed this can cause issues when an event triggered another NMI but is processed in the current NMI. This causes the next NMI to go unprocessed and become an 'unknown' NMI. To handle this, we first have to flag whether or not the NMI handler handled more than one event or not. If it did, then there exists a chance that the next NMI might be already processed. Once the NMI is flagged as a candidate to be swallowed, we next look for a back-to-back NMI condition. This is determined by looking at the %rip from pt_regs. If it is the same as the previous NMI, it is assumed the cpu did not have a chance to jump back into a non-NMI context and execute code and instead handled another NMI. If both of those conditions are true then we will swallow any unknown NMI. There still exists a chance that we accidentally swallow a real unknown NMI, but for now things seem better. An optimization has also been added to the nmi notifier rountine. Because x86 can latch up to one NMI while currently processing an NMI, we don't have to worry about executing _all_ the handlers in a standalone NMI. The idea is if multiple NMIs come in, the second NMI will represent them. For those back-to-back NMI cases, we have the potentail to drop NMIs. Therefore only execute all the handlers in the second half of a detected back-to-back NMI. Signed-off-by: Don Zickus <dzickus@redhat.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1317409584-23662-5-git-send-email-dzickus@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
ea70ef3d9db1cbfd439f3e3f124c28ef4fe5835d	28-Apr-2011	Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>	sched: x86_32 Fix typo in switch_to() description This patch fixes the typo in parameters passed to x86_32 switch_to() description. Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
a0bfa1373859e9d11dc92561a8667588803e42d8	02-Apr-2011	Len Brown <len.brown@intel.com>	cpuidle: stop depending on pm_idle cpuidle users should call cpuidle_call_idle() directly rather than via (pm_idle)() function pointer. Architecture may choose to continue using (pm_idle)(), but cpuidle need not depend on it: my_arch_cpu_idle() ... if(cpuidle_call_idle()) pm_idle(); cc: Kevin Hilman <khilman@deeprootsystems.com> cc: Paul Mundt <lethal@linux-sh.org> cc: x86@kernel.org Acked-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
dac853ae89043f1b7752875300faf614de43c74b	09-Jun-2011	Mathias Krause <minipli@googlemail.com>	exec: delay address limit change until point of no return Unconditionally changing the address limit to USER_DS and not restoring it to its old value in the error path is wrong because it prevents us using kernel memory on repeated calls to this function. This, in fact, breaks the fallback of hard coded paths to the init program from being ever successful if the first candidate fails to load. With this patch applied switching to USER_DS is delayed until the point of no return is reached which makes it possible to have a multi-arch rootfs with one arch specific init binary for each of the (hard coded) probed paths. Since the address limit is already set to USER_DS when start_thread() will be invoked, this redundancy can be safely removed. Signed-off-by: Mathias Krause <minipli@googlemail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
f77cfe4ea21760268c0277fa3e4b02dfd2a2c2f4	07-Jan-2011	Thomas Renninger <trenn@suse.de>	cpuidle/x86/perf: fix power:cpu_idle double end events and throw cpu_idle events from the cpuidle layer Currently intel_idle and acpi_idle driver show double cpu_idle "exit idle" events -> this patch fixes it and makes cpu_idle events throwing less complex. It also introduces cpu_idle events for all architectures which use the cpuidle subsystem, namely: - arch/arm/mach-at91/cpuidle.c - arch/arm/mach-davinci/cpuidle.c - arch/arm/mach-kirkwood/cpuidle.c - arch/arm/mach-omap2/cpuidle34xx.c - arch/drivers/acpi/processor_idle.c (for all cases, not only mwait) - arch/x86/kernel/process.c (did throw events before, but was a mess) - drivers/idle/intel_idle.c (did throw events before) Convention should be: Fire cpu_idle events inside the current pm_idle function (not somewhere down the the callee tree) to keep things easy. Current possible pm_idle functions in X86: c1e_idle, poll_idle, cpuidle_idle_call, mwait_idle, default_idle -> this is really easy is now. This affects userspace: The type field of the cpu_idle power event can now direclty get mapped to: /sys/devices/system/cpu/cpuX/cpuidle/stateX/{name,desc,usage,time,...} instead of throwing very CPU/mwait specific values. This change is not visible for the intel_idle driver. For the acpi_idle driver it should only be visible if the vendor misses out C-states in his BIOS. Another (perf timechart) patch reads out cpuidle info of cpu_idle events from: /sys/.../cpuidle/stateX/*, then the cpuidle events are mapped to the correct C-/cpuidle state again, even if e.g. vendors miss out C-states in their BIOS and for example only export C1 and C3. -> everything is fine. Signed-off-by: Thomas Renninger <trenn@suse.de> CC: Robert Schoene <robert.schoene@tu-dresden.de> CC: Jean Pihet <j-pihet@ti.com> CC: Arjan van de Ven <arjan@linux.intel.com> CC: Ingo Molnar <mingo@elte.hu> CC: Frederic Weisbecker <fweisbec@gmail.com> CC: linux-pm@lists.linux-foundation.org CC: linux-acpi@vger.kernel.org CC: linux-kernel@vger.kernel.org CC: linux-perf-users@vger.kernel.org CC: linux-omap@vger.kernel.org Signed-off-by: Len Brown <len.brown@intel.com>
25e41933b58777f2d020c3b0186b430ea004ec28	03-Jan-2011	Thomas Renninger <trenn@suse.de>	perf: Clean up power events by introducing new, more generic ones Add these new power trace events: power:cpu_idle power:cpu_frequency power:machine_suspend The old C-state/idle accounting events: power:power_start power:power_end Have now a replacement (but we are still keeping the old tracepoints for compatibility): power:cpu_idle and power:power_frequency is replaced with: power:cpu_frequency power:machine_suspend is newly introduced. Jean Pihet has a patch integrated into the generic layer (kernel/power/suspend.c) which will make use of it. the type= field got removed from both, it was never used and the type is differed by the event type itself. perf timechart userspace tool gets adjusted in a separate patch. Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Jean Pihet <jean.pihet@newoldbits.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: rjw@sisk.pl LKML-Reference: <1294073445-14812-3-git-send-email-trenn@suse.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1290072314-31155-2-git-send-email-trenn@suse.de>
c882e0feb937af4e5b991cbd1c81536f37053e86	14-Jun-2010	Robert Schöne <robert.schoene@tu-dresden.de>	x86, perf: Add power_end event to process_*.c cpu_idle routine Systems using the idle thread from process_32.c and process_64.c do not generate power_end events which could be traced using perf. This patch adds the event generation for such systems. Signed-off-by: Robert Schoene <robert.schoene@tu-dresden.de> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> LKML-Reference: <1276515440.5441.45.camel@localhost> Signed-off-by: Ingo Molnar <mingo@elte.hu>
86603283326c9e95e5ad4e9fdddeec93cac5d9ad	06-May-2010	Avi Kivity <avi@redhat.com>	x86: Introduce 'struct fpu' and related API Currently all fpu state access is through tsk->thread.xstate. Since we wish to generalize fpu access to non-task contexts, wrap the state in a new 'struct fpu' and convert existing access to use an fpu API. Signal frame handlers are not converted to the API since they will remain task context only things. Signed-off-by: Avi Kivity <avi@redhat.com> Acked-by: Suresh Siddha <suresh.b.siddha@intel.com> LKML-Reference: <1273135546-29690-3-git-send-email-avi@redhat.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
faa4602e47690fb11221e00f9b9697c8dc0d4b19	25-Mar-2010	Peter Zijlstra <a.p.zijlstra@chello.nl>	x86, perf, bts, mm: Delete the never used BTS-ptrace code Support for the PMU's BTS features has been upstreamed in v2.6.32, but we still have the old and disabled ptrace-BTS, as Linus noticed it not so long ago. It's buggy: TIF_DEBUGCTLMSR is trampling all over that MSR without regard for other uses (perf) and doesn't provide the flexibility needed for perf either. Its users are ptrace-block-step and ptrace-bts, since ptrace-bts was never used and ptrace-block-step can be implemented using a much simpler approach. So axe all 3000 lines of it. That includes the locked_memory() APIs in mm/mlock.c as well. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Roland McGrath <roland@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Markus Metzger <markus.t.metzger@intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Andrew Morton <akpm@linux-foundation.org> LKML-Reference: <20100325135413.938004390@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
3bef444797f7624f8fbd27f4e0334ce96a108725	13-Jan-2010	Brian Gerst <brgerst@gmail.com>	x86: Merge show_regs() Using kernel_stack_pointer() allows 32-bit and 64-bit versions to be merged. This is more correct for 64-bit, since the old %rsp is always saved on the stack. Signed-off-by: Brian Gerst <brgerst@gmail.com> LKML-Reference: <1263397555-27695-1-git-send-email-brgerst@gmail.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
d015a092989d673df44a5ad6866dc5d5006b7a2a	28-Dec-2009	Pekka Enberg <penberg@cs.helsinki.fi>	x86: Use KERN_DEFAULT log-level in __show_regs() Andrew Morton reported a strange looking kmemcheck warning: WARNING: kmemcheck: Caught 32-bit read from uninitialized memory (ffff88004fba6c20) 0000000000000000310000000000000000000000000000002413000000c9ffff u u u u u u u u u u u u u u u u i i i i i i i i u u u u u u u u [<ffffffff810af3aa>] kmemleak_scan+0x25a/0x540 [<ffffffff810afbcb>] kmemleak_scan_thread+0x5b/0xe0 [<ffffffff8104d0fe>] kthread+0x9e/0xb0 [<ffffffff81003074>] kernel_thread_helper+0x4/0x10 [<ffffffffffffffff>] 0xffffffffffffffff The above printout is missing register dump completely. The problem here is that the output comes from syslog which doesn't show KERN_INFO log-level messages. We didn't see this before because both of us were testing on 32-bit kernels which use the _default_ log-level. Fix that up by explicitly using KERN_DEFAULT log-level for __show_regs() printks. Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Vegard Nossum <vegard.nossum@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1261988819.4641.2.camel@penberg-laptop> Signed-off-by: Ingo Molnar <mingo@elte.hu>
df59e7bf439918f523ac29e996ec1eebbed60440	09-Dec-2009	Brian Gerst <brgerst@gmail.com>	x86: Merge kernel_thread() Signed-off-by: Brian Gerst <brgerst@gmail.com> LKML-Reference: <1260380084-3707-6-git-send-email-brgerst@gmail.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
f443ff4201dd25cd4dec183f9919ecba90c8edc2	09-Dec-2009	Brian Gerst <brgerst@gmail.com>	x86: Sync 32/64-bit kernel_thread Signed-off-by: Brian Gerst <brgerst@gmail.com> LKML-Reference: <1260380084-3707-5-git-send-email-brgerst@gmail.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
e840227c141116171c89ab1abb5cc9fee6fdb488	09-Dec-2009	Brian Gerst <brgerst@gmail.com>	x86, 32-bit: Use same regs as 64-bit for kernel_thread_helper The arg should be in %eax, but that is clobbered by the return value of clone. The function pointer can be in any register. Also, don't push args onto the stack, since regparm(3) is the normal calling convention now. Signed-off-by: Brian Gerst <brgerst@gmail.com> LKML-Reference: <1260380084-3707-4-git-send-email-brgerst@gmail.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
f839bbc5c81b1c92ff8e81c360e9564f7b961b2e	10-Dec-2009	Brian Gerst <brgerst@gmail.com>	x86: Merge sys_clone Change 32-bit sys_clone to new PTREGSCALL stub, and merge with 64-bit. Signed-off-by: Brian Gerst <brgerst@gmail.com> LKML-Reference: <1260403316-5679-7-git-send-email-brgerst@gmail.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
11cf88bd0b8165b65aaabaee0977e9a3ad474ab7	10-Dec-2009	Brian Gerst <brgerst@gmail.com>	x86: Merge sys_execve Change 32-bit sys_execve to PTREGSCALL3, and merge with 64-bit. Signed-off-by: Brian Gerst <brgerst@gmail.com> LKML-Reference: <1260403316-5679-4-git-send-email-brgerst@gmail.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
814e2c84a722c45650a9b8f52285d7ba6874f63b	08-Dec-2009	Andy Isaacson <adi@hexapodia.org>	x86: Factor duplicated code out of __show_regs() into show_regs_common() Unify x86_32 and x86_64 implementations of __show_regs() header, standardizing on the x86_64 format string in the process. Also, 32-bit will now call print_modules. Signed-off-by: Andy Isaacson <adi@hexapodia.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Robert Hancock <hancockrwd@gmail.com> Cc: Richard Zidlicky <rz@linux-m68k.org> Cc: Andrew Morton <akpm@linux-foundation.org> LKML-Reference: <20091208082942.GA27174@hexapodia.org> [ v2: resolved conflict ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
24f1e32c60c45c89a997c73395b69c8af6f0a84e	09-Sep-2009	Frederic Weisbecker <fweisbec@gmail.com>	hw-breakpoints: Rewrite the hw-breakpoints layer on top of perf events This patch rebase the implementation of the breakpoints API on top of perf events instances. Each breakpoints are now perf events that handle the register scheduling, thread/cpu attachment, etc.. The new layering is now made as follows: ptrace kgdb ftrace perf syscall \ \| / / \ \| / / / Core breakpoint API / / \| / \| / Breakpoints perf events \| \| Breakpoints PMU ---- Debug Register constraints handling (Part of core breakpoint API) \| \| Hardware debug registers Reasons of this rewrite: - Use the centralized/optimized pmu registers scheduling, implying an easier arch integration - More powerful register handling: perf attributes (pinned/flexible events, exclusive/non-exclusive, tunable period, etc...) Impact: - New perf ABI: the hardware breakpoints counters - Ptrace breakpoints setting remains tricky and still needs some per thread breakpoints references. Todo (in the order): - Support breakpoints perf counter events for perf tools (ie: implement perf_bpcounter_event()) - Support from perf tools Changes in v2: - Follow the perf "event " rename - The ptrace regression have been fixed (ptrace breakpoint perf events weren't released when a task ended) - Drop the struct hw_breakpoint and store generic fields in perf_event_attr. - Separate core and arch specific headers, drop asm-generic/hw_breakpoint.h and create linux/hw_breakpoint.h - Use new generic len/type for breakpoint - Handle off case: when breakpoints api is not supported by an arch Changes in v3: - Fix broken CONFIG_KVM, we need to propagate the breakpoint api changes to kvm when we exit the guest and restore the bp registers to the host. Changes in v4: - Drop the hw_breakpoint_restore() stub as it is only used by KVM - EXPORT_SYMBOL_GPL hw_breakpoint_restore() as KVM can be built as a module - Restore the breakpoints unconditionally on kvm guest exit: TIF_DEBUG_THREAD doesn't anymore cover every cases of running breakpoints and vcpu->arch.switch_db_regs might not always be set when the guest used debug registers. (Waiting for a reliable optimization) Changes in v5: - Split-up the asm-generic/hw-breakpoint.h moving to linux/hw_breakpoint.h into a separate patch - Optimize the breakpoints restoring while switching from kvm guest to host. We only want to restore the state if we have active breakpoints to the host, otherwise we don't care about messed-up address registers. - Add asm/hw_breakpoint.h to Kbuild - Fix bad breakpoint type in trace_selftest.c Changes in v6: - Fix wrong header inclusion in trace.h (triggered a build error with CONFIG_FTRACE_SELFTEST Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Prasad <prasad@linux.vnet.ibm.com> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jan Kiszka <jan.kiszka@web.de> Cc: Jiri Slaby <jirislaby@gmail.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Avi Kivity <avi@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Masami Hiramatsu <mhiramat@redhat.com> Cc: Paul Mundt <lethal@linux-sh.org>
a489ca355efaf9efa4990b0f8f30ab650a206273	03-Nov-2009	Arjan van de Ven <arjan@linux.intel.com>	x86: Make sure we also print a Code: line for show_regs() show_regs() is called as a mini BUG() equivalent in some places, specifically for the "scheduling while atomic" case. Unfortunately right now it does not print a Code: line unlike a real bug/oops. This patch changes the x86 implementation of show_regs() so that it calls the same function as oopses do to print the registers as well as the Code: line. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> LKML-Reference: <20091102165915.4a980fc0@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
def3c5d0a34e4b09b3cea4435c17209ad347104d	12-Oct-2009	H. Peter Anvin <hpa@zytor.com>	x86: use kernel_stack_pointer() in process_32.c The way to obtain a kernel-mode stack pointer from a struct pt_regs in 32-bit mode is "subtle": the stack doesn't actually contain the stack pointer, but rather the location where it would have been marks the actual previous stack frame. For clarity, use kernel_stack_pointer() instead of coding this weirdness explicitly. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
bdf977b37418cdf8a2252504779a7e12a09b7575	03-Aug-2009	Tejun Heo <tj@kernel.org>	x86, percpu: Collect hot percpu variables into one cacheline On x86_64, percpu variables current_task and kernel_stack are used for get_current() and current_thread_info() respectively and thus are often used close to each other. Move definition of current_task to kernel/cpu/common.c right above kernel_stack definition and align it to cacheline so that they always fall into the same cacheline. Two percpu variables defined there together - irq_stack_ptr and irq_count - are also pretty hot and will benefit from sharing the cacheline. For consistency, current_task definition for x86_32 is also moved to kernel/cpu/common.c. Putting current_task and kernel_stack into the same cacheline was suggested by Linus Torvalds. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2fcddce10f6771cfa0c56fd1e826d50d67d100b7	24-Apr-2009	Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>	x86-32: make sure clts is batched during context switch If we're preloading the fpu state during context switch, make sure the clts happens while we're batching the cpu context update, then do the actual __math_state_restore once the updates are flushed. This allows more efficient context switches when running paravirtualized, as all the hypercalls can be folded together into one. [ Impact: optimise paravirtual FPU context switch ] Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: Alok Kataria <akataria@vmware.com> Cc: Rusty Russell <rusty@rustcorp.com.au>
66cb5917295958652ff6ba36d83f98f2379c46b4	01-Jun-2009	K.Prasad <prasad@linux.vnet.ibm.com>	hw-breakpoints: use the new wrapper routines to access debug registers in process/thread code This patch enables the use of abstract debug registers in process-handling routines, according to the new hardware breakpoint Api. [ Impact: adapt thread breakpoints handling code to the new breakpoint Api ] Original-patch-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com> Reviewed-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
bf78ad69cd351798b9447a269c6bd41ce1f111f4	12-May-2009	Amerigo Wang <amwang@redhat.com>	x86: process.c, remove useless headers <stdarg.h> is not needed by these files, remove them. [ Impact: cleanup ] Signed-off-by: WANG Cong <amwang@redhat.com> Cc: akpm@linux-foundation.org LKML-Reference: <20090512032956.5040.77055.sendpatchset@localhost.localdomain> Signed-off-by: Ingo Molnar <mingo@elte.hu>
9d62dcdfa6f6fc843f7d9b494bcd48f00b94f883	12-May-2009	Amerigo Wang <amwang@redhat.com>	x86: merge process.c a bit Merge arch_align_stack() and arch_randomize_brk(), since they are the same. Tested on x86_64. [ Impact: cleanup ] Signed-off-by: Amerigo Wang <amwang@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2311f0de21c17b2a8b960677a9cccfbfa52beb35	03-Apr-2009	Markus Metzger <markus.t.metzger@intel.com>	x86, ds: add leakage warning Add a warning in case a debug store context is not removed before the task it is attached to is freed. Remove the old warning at thread exit. It is too early. Declare the debug store context field in thread_struct unconditionally. Remove ds_copy_thread() and ds_exit_thread() and do the work directly in process*.c. Signed-off-by: Markus Metzger <markus.t.metzger@intel.com> Cc: roland@redhat.com Cc: eranian@googlemail.com Cc: oleg@redhat.com Cc: juan.villacis@intel.com Cc: ak@linux.jf.intel.com LKML-Reference: <20090403144601.254472000@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
6f2c55b843836d26528c56a0968689accaedbc67	03-Apr-2009	Alexey Dobriyan <adobriyan@gmail.com>	Simplify copy_thread() First argument unused since 2.3.11. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
224101ed69d3fbb486868e0f6e0f9fa37302efb4	18-Feb-2009	Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>	x86/paravirt: finish change from lazy cpu to context switch start/end Impact: fix lazy context switch API Pass the previous and next tasks into the context switch start end calls, so that the called functions can properly access the task state (esp in end_context_switch, in which the next task is not yet completely current). Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
7fd7d83d49914f03aefffba6aee09032fcd54cce	18-Feb-2009	Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>	x86/pvops: replace arch_enter_lazy_cpu_mode with arch_start_context_switch Impact: simplification, prepare for later changes Make lazy cpu mode more specific to context switching, so that it makes sense to do more context-switch specific things in the callbacks. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>