summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/kernel/asm-offsets.c
Commit message (Collapse)AuthorAgeFilesLines
...
* | powerpc: Account time using timebase rather than PURRPaul Mackerras2010-09-021-3/+5
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, when CONFIG_VIRT_CPU_ACCOUNTING is enabled, we use the PURR register for measuring the user and system time used by processes, as well as other related times such as hardirq and softirq times. This turns out to be quite confusing for users because it means that a program will often be measured as taking less time when run on a multi-threaded processor (SMT2 or SMT4 mode) than it does when run on a single-threaded processor (ST mode), even though the program takes longer to finish. The discrepancy is accounted for as stolen time, which is also confusing, particularly when there are no other partitions running. This changes the accounting to use the timebase instead, meaning that the reported user and system times are the actual number of real-time seconds that the program was executing on the processor thread, regardless of which SMT mode the processor is in. Thus a program will generally show greater user and system times when run on a multi-threaded processor than on a single-threaded processor. On pSeries systems on POWER5 or later processors, we measure the stolen time (time when this partition wasn't running) using the hypervisor dispatch trace log. We check for new entries in the log on every entry from user mode and on every transition from kernel process context to soft or hard IRQ context (i.e. when account_system_vtime() gets called). So that we can correctly distinguish time stolen from user time and time stolen from system time, without having to check the log on every exit to user mode, we store separate timestamps for exit to user mode and entry from user mode. On systems that have a SPURR (POWER6 and POWER7), we read the SPURR in account_system_vtime() (as before), and then apportion the SPURR ticks since the last time we read it between scaled user time and scaled system time according to the relative proportions of user time and system time over the same interval. This avoids having to read the SPURR on every kernel entry and exit. On systems that have PURR but not SPURR (i.e., POWER5), we do the same using the PURR rather than the SPURR. This disables the DTL user interface in /sys/debug/kernel/powerpc/dtl for now since it conflicts with the use of the dispatch trace log by the time accounting code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc: Optimise per cpu accesses on 64bitAnton Blanchard2010-07-091-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now we dynamically allocate the paca array, it takes an extra load whenever we want to access another cpu's paca. One place we do that a lot is per cpu variables. A simple example: DEFINE_PER_CPU(unsigned long, vara); unsigned long test4(int cpu) { return per_cpu(vara, cpu); } This takes 4 loads, 5 if you include the actual load of the per cpu variable: ld r11,-32760(r30) # load address of paca pointer ld r9,-32768(r30) # load link address of percpu variable sldi r3,r29,9 # get offset into paca (each entry is 512 bytes) ld r0,0(r11) # load paca pointer add r3,r0,r3 # paca + offset ld r11,64(r3) # load paca[cpu].data_offset ldx r3,r9,r11 # load per cpu variable If we remove the ppc64 specific per_cpu_offset(), we get the generic one which indexes into a statically allocated array. This removes one load and one add: ld r11,-32760(r30) # load address of __per_cpu_offset ld r9,-32768(r30) # load link address of percpu variable sldi r3,r29,3 # get offset into __per_cpu_offset (each entry 8 bytes) ldx r11,r11,r3 # load __per_cpu_offset[cpu] ldx r3,r9,r11 # load per cpu variable Having all the offsets in one array also helps when iterating over a per cpu variable across a number of cpus, such as in the scheduler. Before we would need to load one paca cacheline when calculating each per cpu offset. Now we have 16 (128 / sizeof(long)) per cpu offsets in each cacheline. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc: Rework VDSO gettimeofday to prevent time going backwardsPaul Mackerras2010-07-091-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently it is possible for userspace to see the result of gettimeofday() going backwards by 1 microsecond, assuming that userspace is using the gettimeofday() in the VDSO. The VDSO gettimeofday() algorithm computes the time in "xsecs", which are units of 2^-20 seconds, or approximately 0.954 microseconds, using the algorithm now = (timebase - tb_orig_stamp) * tb_to_xs + stamp_xsec and then converts the time in xsecs to seconds and microseconds. The kernel updates the tb_orig_stamp and stamp_xsec values every tick in update_vsyscall(). If the length of the tick is not an integer number of xsecs, then some precision is lost in converting the current time to xsecs. For example, with CONFIG_HZ=1000, the tick is 1ms long, which is 1048.576 xsecs. That means that stamp_xsec will advance by either 1048 or 1049 on each tick. With the right conditions, it is possible for userspace to get (timebase - tb_orig_stamp) * tb_to_xs being 1049 if the kernel is slightly late in updating the vdso_datapage, and then for stamp_xsec to advance by 1048 when the kernel does update it, and for userspace to then see (timebase - tb_orig_stamp) * tb_to_xs being zero due to integer truncation. The result is that time appears to go backwards by 1 microsecond. To fix this we change the VDSO gettimeofday to use a new field in the VDSO datapage which stores the nanoseconds part of the time as a fractional number of seconds in a 0.32 binary fraction format. (Or put another way, as a 32-bit number in units of 0.23283 ns.) This is convenient because we can use the mulhwu instruction to convert it to either microseconds or nanoseconds. Since it turns out that computing the time of day using this new field is simpler than either using stamp_xsec (as gettimeofday does) or stamp_xtime.tv_nsec (as clock_gettime does), this converts both gettimeofday and clock_gettime to use the new field. The existing __do_get_tspec function is converted to use the new field and take a parameter in r7 that indicates the desired resolution, 1,000,000 for microseconds or 1,000,000,000 for nanoseconds. The __do_get_xsec function is then unused and is deleted. The new algorithm is now = ((timebase - tb_orig_stamp) << 12) * tb_to_xs + (stamp_xtime_seconds << 32) + stamp_sec_fraction with 'now' in units of 2^-32 seconds. That is then converted to seconds and either microseconds or nanoseconds with seconds = now >> 32 partseconds = ((now & 0xffffffff) * resolution) >> 32 The 32-bit VDSO code also makes a further simplification: it ignores the bottom 32 bits of the tb_to_xs value, which is a 0.64 format binary fraction. Doing so gets rid of 4 multiply instructions. Assuming a timebase frequency of 1GHz or less and an update interval of no more than 10ms, the upper 32 bits of tb_to_xs will be at least 4503599, so the error from ignoring the low 32 bits will be at most 2.2ns, which is more than an order of magnitude less than the time taken to do gettimeofday or clock_gettime on our fastest processors, so there is no possibility of seeing inconsistent values due to this. This also moves update_gtod() down next to its only caller, and makes update_vsyscall use the time passed in via the wall_time argument rather than accessing xtime directly. At present, wall_time always points to xtime, but that could change in future. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* Merge branch 'kvm-updates/2.6.35' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2010-05-211-41/+61
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'kvm-updates/2.6.35' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (269 commits) KVM: x86: Add missing locking to arch specific vcpu ioctls KVM: PPC: Add missing vcpu_load()/vcpu_put() in vcpu ioctls KVM: MMU: Segregate shadow pages with different cr0.wp KVM: x86: Check LMA bit before set_efer KVM: Don't allow lmsw to clear cr0.pe KVM: Add cpuid.txt file KVM: x86: Tell the guest we'll warn it about tsc stability x86, paravirt: don't compute pvclock adjustments if we trust the tsc x86: KVM guest: Try using new kvm clock msrs KVM: x86: export paravirtual cpuid flags in KVM_GET_SUPPORTED_CPUID KVM: x86: add new KVMCLOCK cpuid feature KVM: x86: change msr numbers for kvmclock x86, paravirt: Add a global synchronization point for pvclock x86, paravirt: Enable pvclock flags in vcpu_time_info structure KVM: x86: Inject #GP with the right rip on efer writes KVM: SVM: Don't allow nested guest to VMMCALL into host KVM: x86: Fix exception reinjection forced to true KVM: Fix wallclock version writing race KVM: MMU: Don't read pdptrs with mmu spinlock held in mmu_alloc_roots KVM: VMX: enable VMXON check with SMX enabled (Intel TXT) ...
| * PPC: Export SWITCH_FRAME_SIZEAlexander Graf2010-05-171-1/+1
| | | | | | | | | | | | | | | | | | | | We need the SWITCH_FRAME_SIZE define on Book3S_32 now too. So let's export it unconditionally. CC: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Alexander Graf <agraf@suse.de> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: PPC: Add SVCPU to Book3S_32Alexander Graf2010-05-171-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | We need to keep the pointer to the shadow vcpu somewhere accessible from within really early interrupt code. The best fit I found was the thread struct, as that resides in an SPRG. So let's put a pointer to the shadow vcpu in the thread struct and add an asm-offset so we can find it. Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: PPC: Use now shadowed vcpu fieldsAlexander Graf2010-05-171-37/+54
| | | | | | | | | | | | | | | | | | | | | | The shadow vcpu now contains some fields we don't use from the vcpu anymore. Access to them happens using inline functions that happily use the shadow vcpu fields. So let's now ifdef them out to booke only and add asm-offsets. Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: PPC: Use CONFIG_PPC_BOOK3S defineAlexander Graf2010-05-171-3/+3
| | | | | | | | | | | | | | | | | | | | Upstream recently added a new name for PPC64: Book3S_64. So instead of using CONFIG_PPC64 we should use CONFIG_PPC_BOOK3S consotently. That makes understanding the code easier (I hope). Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
* | Merge branch 'next' of ↵Linus Torvalds2010-05-211-0/+9
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (92 commits) powerpc: Remove unused 'protect4gb' boot parameter powerpc: Build-in e1000e for pseries & ppc64_defconfig powerpc/pseries: Make request_ras_irqs() available to other pseries code powerpc/numa: Use ibm,architecture-vec-5 to detect form 1 affinity powerpc/numa: Set a smaller value for RECLAIM_DISTANCE to enable zone reclaim powerpc: Use smt_snooze_delay=-1 to always busy loop powerpc: Remove check of ibm,smt-snooze-delay OF property powerpc/kdump: Fix race in kdump shutdown powerpc/kexec: Fix race in kexec shutdown powerpc/kexec: Speedup kexec hash PTE tear down powerpc/pseries: Add hcall to read 4 ptes at a time in real mode powerpc: Use more accurate limit for first segment memory allocations powerpc/kdump: Use chip->shutdown to disable IRQs powerpc/kdump: CPUs assume the context of the oopsing CPU powerpc/crashdump: Do not fail on NULL pointer dereferencing powerpc/eeh: Fix oops when probing in early boot powerpc/pci: Check devices status property when scanning OF tree powerpc/vio: Switch VIO Bus PM to use generic helpers powerpc: Avoid bad relocations in iSeries code powerpc: Use common cpu_die (fixes SMP+SUSPEND build) ...
| * | powerpc/kexec: Fix race in kexec shutdownMichael Neuling2010-05-211-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In kexec_prepare_cpus, the primary CPU IPIs the secondary CPUs to kexec_smp_down(). kexec_smp_down() calls kexec_smp_wait() which sets the hw_cpu_id() to -1. The primary does this while leaving IRQs on which means the primary can take a timer interrupt which can lead to the IPIing one of the secondary CPUs (say, for a scheduler re-balance) but since the secondary CPU now has a hw_cpu_id = -1, we IPI CPU -1... Kaboom! We are hitting this case regularly on POWER7 machines. There is also a second race, where the primary will tear down the MMU mappings before knowing the secondaries have entered real mode. Also, the secondaries are clearing out any pending IPIs before guaranteeing that no more will be received. This changes kexec_prepare_cpus() so that we turn off IRQs in the primary CPU much earlier. It adds a paca flag to say that the secondaries have entered the kexec_smp_down() IPI and turned off IRQs, rather than overloading hw_cpu_id with -1. This new paca flag is again used to in indicate when the secondaries has entered real mode. It also ensures that all CPUs have their IRQs off before we clear out any pending IPI requests (in kexec_cpu_down()) to ensure there are no trailing IPIs left unacknowledged. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | powerpc/fsl-booke: Move loadcam_entry back to asm code to fix SMP ftraceKumar Gala2010-05-171-0/+8
| |/ | | | | | | | | | | | | | | | | | | When we build with ftrace enabled its possible that loadcam_entry would have used the stack pointer (even though the code doesn't need it). We call loadcam_entry in __secondary_start before the stack is setup. To ensure that loadcam_entry doesn't use the stack pointer the easiest solution is to just have it in asm code. Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
* | powerpc/perf_event: Fix oops due to perf_event_do_pending callPaul Mackerras2010-05-121-1/+0
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | Anton Blanchard found that large POWER systems would occasionally crash in the exception exit path when profiling with perf_events. The symptom was that an interrupt would occur late in the exit path when the MSR[RI] (recoverable interrupt) bit was clear. Interrupts should be hard-disabled at this point but they were enabled. Because the interrupt was not recoverable the system panicked. The reason is that the exception exit path was calling perf_event_do_pending after hard-disabling interrupts, and perf_event_do_pending will re-enable interrupts. The simplest and cleanest fix for this is to use the same mechanism that 32-bit powerpc does, namely to cause a self-IPI by setting the decrementer to 1. This means we can remove the tests in the exception exit path and raw_local_irq_restore. This also makes sure that the call to perf_event_do_pending from timer_interrupt() happens within irq_enter/irq_exit. (Note that calling perf_event_do_pending from timer_interrupt does not mean that there is a possible 1/HZ latency; setting the decrementer to 1 ensures that the timer interrupt will happen immediately, i.e. within one timebase tick, which is a few nanoseconds or 10s of nanoseconds.) Signed-off-by: Paul Mackerras <paulus@samba.org> Cc: stable@kernel.org Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* KVM: PPC: Keep SRR1 flags around in shadow_msrAlexander Graf2010-03-011-0/+1
| | | | | | | | | | | | | | | | | | | SRR1 stores more information that just the MSR value. It also stores valuable information about the type of interrupt we received, for example whether the storage interrupt we just got was because of a missing htab entry or not. We use that information to speed up the exit path. Now if we get preempted before we can interpret the shadow_msr values, we get into vcpu_put which then calls the MSR handler, which then sets all the SRR1 information bits in shadow_msr to 0. Great. So let's preserve the SRR1 specific bits in shadow_msr whenever we set the MSR. They don't hurt. Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: PPC: Call SLB patching code in interrupt safe mannerAlexander Graf2010-03-011-2/+1
| | | | | | | | | | | | | | | | | | Currently we're racy when doing the transition from IR=1 to IR=0, from the module memory entry code to the real mode SLB switching code. To work around that I took a look at the RTAS entry code which is faced with a similar problem and did the same thing: A small helper in linear mapped memory that does mtmsr with IR=0 and then RFIs info the actual handler. Thanks to that trick we can safely take page faults in the entry code and only need to be really wary of what to do as of the SLB switching part. Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: PPC: Use PACA backed shadow vcpuAlexander Graf2010-03-011-3/+30
| | | | | | | | | | | | | | | We're being horribly racy right now. All the entry and exit code hijacks random fields from the PACA that could easily be used by different code in case we get interrupted, for example by a #MC or even page fault. After discussing this with Ben, we figured it's best to reserve some more space in the PACA and just shove off some vcpu state to there. That way we can drastically improve the readability of the code, make it less racy and less complex. Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
* powerpc/fsl-booke: Rework TLB CAM codeKumar Gala2009-11-201-3/+0
| | | | | | | | | Re-write the code so its more standalone and fixed some issues: * Bump'd # of CAM entries to 64 to support e500mc * Make the code handle MAS7 properly * Use pr_cont instead of creating a string as we go Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
* Export new PACA constants in asm-offsetsAlexander Graf2009-11-051-0/+5
| | | | | | | | | | In order to access fields in the PACA from assembly code, we need to generate offsets using asm-offsets.c. So let's add the new PACA related bits, we just introduced! Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* Add Book3s_64 offsets to asm-offsets.cAlexander Graf2009-11-051-0/+13
| | | | | | | | We need to access some VCPU fields from assembly code. In order to get the proper offsets, we have to define them in asm-offsets.c. Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* perf: Do the big rename: Performance Counters -> Performance EventsIngo Molnar2009-09-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Bye-bye Performance Counters, welcome Performance Events! In the past few months the perfcounters subsystem has grown out its initial role of counting hardware events, and has become (and is becoming) a much broader generic event enumeration, reporting, logging, monitoring, analysis facility. Naming its core object 'perf_counter' and naming the subsystem 'perfcounters' has become more and more of a misnomer. With pending code like hw-breakpoints support the 'counter' name is less and less appropriate. All in one, we've decided to rename the subsystem to 'performance events' and to propagate this rename through all fields, variables and API names. (in an ABI compatible fashion) The word 'event' is also a bit shorter than 'counter' - which makes it slightly more convenient to write/handle as well. Thanks goes to Stephane Eranian who first observed this misnomer and suggested a rename. User-space tooling and ABI compatibility is not affected - this patch should be function-invariant. (Also, defconfigs were not touched to keep the size down.) This patch has been generated via the following script: FILES=$(find * -type f | grep -vE 'oprofile|[^K]config') sed -i \ -e 's/PERF_EVENT_/PERF_RECORD_/g' \ -e 's/PERF_COUNTER/PERF_EVENT/g' \ -e 's/perf_counter/perf_event/g' \ -e 's/nb_counters/nb_events/g' \ -e 's/swcounter/swevent/g' \ -e 's/tpcounter_event/tp_event/g' \ $FILES for N in $(find . -name perf_counter.[ch]); do M=$(echo $N | sed 's/perf_counter/perf_event/g') mv $N $M done FILES=$(find . -name perf_event.*) sed -i \ -e 's/COUNTER_MASK/REG_MASK/g' \ -e 's/COUNTER/EVENT/g' \ -e 's/\<event\>/event_id/g' \ -e 's/counter/event/g' \ -e 's/Counter/Event/g' \ $FILES ... to keep it as correct as possible. This script can also be used by anyone who has pending perfcounters patches - it converts a Linux kernel tree over to the new naming. We tried to time this change to the point in time where the amount of pending patches is the smallest: the end of the merge window. Namespace clashes were fixed up in a preparatory patch - and some stylistic fallout will be fixed up in a subsequent patch. ( NOTE: 'counters' are still the proper terminology when we deal with hardware registers - and these sed scripts are a bit over-eager in renaming them. I've undone some of that, but in case there's something left where 'counter' would be better than 'event' we can undo that on an individual basis instead of touching an otherwise nicely automated patch. ) Suggested-by: Stephane Eranian <eranian@google.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Paul Mackerras <paulus@samba.org> Reviewed-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: David Howells <dhowells@redhat.com> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: <linux-arch@vger.kernel.org> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Merge commit 'paulus-perf/master' into nextBenjamin Herrenschmidt2009-08-201-0/+2
|\
| * powerpc: Allow perf_counters to access user memory at interrupt timePaul Mackerras2009-08-181-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This provides a mechanism to allow the perf_counters code to access user memory in a PMU interrupt routine. Such an access can cause various kinds of interrupt: SLB miss, MMU hash table miss, segment table miss, or TLB miss, depending on the processor. This commit only deals with 64-bit classic/server processors, which use an MMU hash table. 32-bit processors are already able to access user memory at interrupt time. Since we don't soft-disable on 32-bit, we avoid the possibility of reentering hash_page or the TLB miss handlers, since they run with interrupts disabled. On 64-bit processors, an SLB miss interrupt on a user address will update the slb_cache and slb_cache_ptr fields in the paca. This is OK except in the case where a PMU interrupt occurs in switch_slb, which also accesses those fields. To prevent this, we hard-disable interrupts in switch_slb. Interrupts are already soft-disabled at this point, and will get hard-enabled when they get soft-enabled later. This also reworks slb_flush_and_rebolt: to avoid hard-disabling twice, and to make sure that it clears the slb_cache_ptr when called from other callers than switch_slb, the existing routine is renamed to __slb_flush_and_rebolt, which is called by switch_slb and the new version of slb_flush_and_rebolt. Similarly, switch_stab (used on POWER3 and RS64 processors) gets a hard_irq_disable() to protect the per-cpu variables used there and in ste_allocate. If a MMU hashtable miss interrupt occurs, normally we would call hash_page to look up the Linux PTE for the address and create a HPTE. However, hash_page is fairly complex and takes some locks, so to avoid the possibility of deadlock, we check the preemption count to see if we are in a (pseudo-)NMI handler, and if so, we don't call hash_page but instead treat it like a bad access that will get reported up through the exception table mechanism. An interrupt whose handler runs even though the interrupt occurred when soft-disabled (such as the PMU interrupt) is considered a pseudo-NMI handler, which should use nmi_enter()/nmi_exit() rather than irq_enter()/irq_exit(). Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
* | powerpc: Add PACA fields specific to 64-bit Book3E processorsBenjamin Herrenschmidt2009-08-201-0/+14
| | | | | | | | | | | | | | | | This adds various fields in the PACA that are for use specifically by Book3E processors, such as exception save areas, current pgd pointer, special exceptions kernel stacks etc... Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* | powerpc: Add memory management headers for new 64-bit BookEBenjamin Herrenschmidt2009-08-201-1/+4
|/ | | | | | | | | | | | | This adds the PTE and pgtable format definitions, along with changes to the kernel memory map and other definitions related to implementing support for 64-bit Book3E. This also shields some asm-offset bits that are currently only relevant on 32-bit We also move the definition of the "linux" page size constants to the common mmu.h file and add a few sizes that are relevant to embedded processors. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* Merge commit 'origin/master' into nextBenjamin Herrenschmidt2009-06-121-0/+1
|\ | | | | | | | | Manual merge of: arch/powerpc/kernel/asm-offsets.c
| * Merge branch 'linus' into perfcounters/core-v2Ingo Molnar2009-04-061-6/+1
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge reason: we have gathered quite a few conflicts, need to merge upstream Conflicts: arch/powerpc/kernel/Makefile arch/x86/ia32/ia32entry.S arch/x86/include/asm/hardirq.h arch/x86/include/asm/unistd_32.h arch/x86/include/asm/unistd_64.h arch/x86/kernel/cpu/common.c arch/x86/kernel/irq.c arch/x86/kernel/syscall_table_32.S arch/x86/mm/iomap_32.c include/linux/sched.h kernel/Makefile Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * \ Merge commit 'v2.6.29-rc2' into perfcounters/coreIngo Molnar2009-01-211-0/+7
| |\ \ | | | | | | | | | | | | | | | | Conflicts: include/linux/syscalls.h
| * \ \ Merge branch 'master' of ↵Ingo Molnar2009-01-111-0/+1
| |\ \ \ | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/paulus/perfcounters into perfcounters/core
| | * | | powerpc: Provide a way to defer perf counter work until interrupts are enabledPaul Mackerras2009-01-091-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Because 64-bit powerpc uses lazy (soft) interrupt disabling, it is possible for a performance monitor exception to come in when the kernel thinks interrupts are disabled (i.e. when they are soft-disabled but hard-enabled). In such a situation the performance monitor exception handler might have some processing to do (such as process wakeups) which can't be done in what is effectively an NMI handler. This provides a way to defer that work until interrupts get enabled, either in raw_local_irq_restore() or by returning from an interrupt handler to code that had interrupts enabled. We have a per-processor flag that indicates that there is work pending to do when interrupts subsequently get re-enabled. This flag is checked in the interrupt return path and in raw_local_irq_restore(), and if it is set, perf_counter_do_pending() is called to do the pending work. Signed-off-by: Paul Mackerras <paulus@samba.org>
* | | | | powerpc: Separate PACA fields for server CPUsBenjamin Herrenschmidt2009-06-091-15/+17
| |_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch has no effect other than re-ordering PACA fields on current server CPUs. It however is a pre-requisite for future support of BookE 64-bit processors. Various parts of the PACA struct are now moved under some ifdef's, either the new CONFIG_PPC_BOOK3S or CONFIG_PPC_STD_MMU_64, whatever seems more appropriate. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.craashing.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* | | | Merge commit 'origin/master' into nextBenjamin Herrenschmidt2009-03-301-3/+1
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | Manual merge of: arch/powerpc/include/asm/elf.h drivers/i2c/busses/i2c-mpc.c
| * | | | KVM: ppc: No need to include core-header for KVM in asm-offsets.c currentlyHollis Blanchard2009-03-241-3/+1
| | |_|/ | |/| | | | | | | | | | | | | | | | | | Signed-off-by: Liu Yu <yu.liu@freescale.com> Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* | | | powerpc: Remove unused asm-offsets entries for cpu_specMichael Ellerman2009-03-111-3/+0
|/ / / | | | | | | | | | | | | Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* | | Merge commit 'kumar/kumar-next' into nextBenjamin Herrenschmidt2009-01-131-0/+7
|\ \ \ | |/ / |/| |
| * | powerpc/fsl-booke: Don't hard-code size of struct tlbcamTrent Piepho2009-01-071-0/+7
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some assembly code in head_fsl_booke.S hard-coded the size of struct tlbcam to 20 when it indexed the TLBCAM table. Anyone changing the size of struct tlbcam would not know to expect that. The kernel already has a system to get the size of C structures into assembly language files, asm-offsets, so let's use it. The definition of the struct gets moved to a header, so that asm-offsets.c can include it. Signed-off-by: Trent Piepho <tpiepho@freescale.com> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
* | KVM: ppc: Implement in-kernel exit timing statisticsHollis Blanchard2008-12-311-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Existing KVM statistics are either just counters (kvm_stat) reported for KVM generally or trace based aproaches like kvm_trace. For KVM on powerpc we had the need to track the timings of the different exit types. While this could be achieved parsing data created with a kvm_trace extension this adds too much overhead (at least on embedded PowerPC) slowing down the workloads we wanted to measure. Therefore this patch adds a in-kernel exit timing statistic to the powerpc kvm code. These statistic is available per vm&vcpu under the kvm debugfs directory. As this statistic is low, but still some overhead it can be enabled via a .config entry and should be off by default. Since this patch touched all powerpc kvm_stat code anyway this code is now merged and simplified together with the exit timing statistic code (still working with exit timing disabled in .config). Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* | KVM: ppc: directly insert shadow mappings into the hardware TLBHollis Blanchard2008-12-311-6/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Formerly, we used to maintain a per-vcpu shadow TLB and on every entry to the guest would load this array into the hardware TLB. This consumed 1280 bytes of memory (64 entries of 16 bytes plus a struct page pointer each), and also required some assembly to loop over the array on every entry. Instead of saving a copy in memory, we can just store shadow mappings directly into the hardware TLB, accepting that the host kernel will clobber these as part of the normal 440 TLB round robin. When we do that we need less than half the memory, and we have decreased the exit handling time for all guest exits, at the cost of increased number of TLB misses because the host overwrites some guest entries. These savings will be increased on processors with larger TLBs or which implement intelligent flush instructions like tlbivax (which will avoid the need to walk arrays in software). In addition to that and to the code simplification, we have a greater chance of leaving other host userspace mappings in the TLB, instead of forcing all subsequent tasks to re-fault all their mappings. Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* | KVM: ppc: create struct kvm_vcpu_44x and introduce container_of() accessorHollis Blanchard2008-12-311-5/+9
| | | | | | | | | | | | | | | | | | | | | | This patch doesn't yet move all 44x-specific data into the new structure, but is the first step down that path. In the future we may also want to create a struct kvm_vcpu_booke. Based on patch from Liu Yu <yu.liu@freescale.com>. Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* | KVM: ppc: Rename "struct tlbe" to "struct kvmppc_44x_tlbe"Hollis Blanchard2008-12-311-1/+1
|/ | | | | | | | | This will ease ports to other cores. Also remove unused "struct kvm_tlb" while we're at it. Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* powerpc/44x: Support 16K/64K base page sizes on 44xIlya Yanok2008-12-291-0/+4
| | | | | | | | | | | | | | | | | | This adds support for 16k and 64k page sizes on PowerPC 44x processors. The PGDIR table is much smaller than a page when using 16k or 64k pages (512 and 32 bytes respectively) so we allocate the PGDIR with kzalloc() instead of __get_free_pages(). One PTE table covers rather a large memory area when using 16k or 64k pages (32MB or 512MB respectively), so we can easily put FIXMAP and PKMAP in the area covered by one PTE table. Signed-off-by: Yuri Tikhonov <yur@emcraft.com> Signed-off-by: Vladimir Panfilov <pvr@emcraft.com> Signed-off-by: Ilya Yanok <yanok@emcraft.com> Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
* powerpc/mm: Split mmu_context handlingBenjamin Herrenschmidt2008-12-211-0/+1
| | | | | | | | | | This splits the mmu_context handling between 32-bit hash based processors, 64-bit hash based processors and everybody else. This is preliminary work for adding SMP support for BookE processors. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Kumar Gala <galak@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
* powerpc: Improve resolution of VDSO clock_gettimePaul Mackerras2008-11-061-0/+1
| | | | | | | | | | | | | | | | | | | | | | Currently the clock_gettime implementation in the VDSO produces a result with microsecond resolution for the cases that are handled without a system call, i.e. CLOCK_REALTIME and CLOCK_MONOTONIC. The nanoseconds field of the result is obtained by computing a microseconds value and multiplying by 1000. This changes the code in the VDSO to do the computation for clock_gettime with nanosecond resolution. That means that the resolution of the result will ultimately depend on the timebase frequency. Because the timestamp in the VDSO datapage (stamp_xsec, the real time corresponding to the timebase count in tb_orig_stamp) is in units of 2^-20 seconds, it doesn't have sufficient resolution for computing a result with nanosecond resolution. Therefore this adds a copy of xtime to the VDSO datapage and updates it in update_gtod() along with the other time-related fields. Signed-off-by: Paul Mackerras <paulus@samba.org>
* Merge branch 'kvm-updates/2.6.28' of ↵Linus Torvalds2008-10-161-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm * 'kvm-updates/2.6.28' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm: (134 commits) KVM: ia64: Add intel iommu support for guests. KVM: ia64: add directed mmio range support for kvm guests KVM: ia64: Make pmt table be able to hold physical mmio entries. KVM: Move irqchip_in_kernel() from ioapic.h to irq.h KVM: Separate irq ack notification out of arch/x86/kvm/irq.c KVM: Change is_mmio_pfn to kvm_is_mmio_pfn, and make it common for all archs KVM: Move device assignment logic to common code KVM: Device Assignment: Move vtd.c from arch/x86/kvm/ to virt/kvm/ KVM: VMX: enable invlpg exiting if EPT is disabled KVM: x86: Silence various LAPIC-related host kernel messages KVM: Device Assignment: Map mmio pages into VT-d page table KVM: PIC: enhance IPI avoidance KVM: MMU: add "oos_shadow" parameter to disable oos KVM: MMU: speed up mmu_unsync_walk KVM: MMU: out of sync shadow core KVM: MMU: mmu_convert_notrap helper KVM: MMU: awareness of new kvm_mmu_zap_page behaviour KVM: MMU: mmu_parent_walk KVM: x86: trap invlpg KVM: MMU: sync roots on mmu reload ...
| * KVM: powerpc: Map guest userspace with TID=0 mappingsHollis Blanchard2008-10-151-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | When we use TID=N userspace mappings, we must ensure that kernel mappings have been destroyed when entering userspace. Using TID=1/TID=0 for kernel/user mappings and running userspace with PID=0 means that userspace can't access the kernel mappings, but the kernel can directly access userspace. The net is that we don't need to flush the TLB on privilege switches, but we do on guest context switches (which are far more infrequent). Guest boot time performance improvement: about 30%. Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
| * KVM: ppc: Write only modified shadow entries into the TLB on exitHollis Blanchard2008-10-151-0/+1
| | | | | | | | | | | | | | | | | | | | | | Track which TLB entries need to be written, instead of overwriting everything below the high water mark. Typically only a single guest TLB entry will be modified in a single exit. Guest boot time performance improvement: about 15%. Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
| * KVM: ppc: Stop saving host TLB stateHollis Blanchard2008-10-151-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | We're saving the host TLB state to memory on every exit, but never using it. Originally I had thought that we'd want to restore host TLB for heavyweight exits, but that could actually hurt when context switching to an unrelated host process (i.e. not qemu). Since this decreases the performance penalty of all exits, this patch improves guest boot time by about 15%. Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
* | POWERPC: Allow 32-bit hashed pgtable code to support 36-bit physicalBecky Bruce2008-09-241-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This rearranges a bit of code, and adds support for 36-bit physical addressing for configs that use a hashed page table. The 36b physical support is not enabled by default on any config - it must be explicitly enabled via the config system. This patch *only* expands the page table code to accomodate large physical addresses on 32-bit systems and enables the PHYS_64BIT config option for 86xx. It does *not* allow you to boot a board with more than about 3.5GB of RAM - for that, SWIOTLB support is also required (and coming soon). Signed-off-by: Becky Bruce <becky.bruce@freescale.com> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
* | powerpc: Make it possible to move the interrupt handlers away from the kernelPaul Mackerras2008-09-151-0/+2
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This changes the way that the exception prologs transfer control to the handlers in 64-bit kernels with the aim of making it possible to have the prologs separate from the main body of the kernel. Now, instead of computing the address of the handler by taking the top 32 bits of the paca address (to get the 0xc0000000........ part) and ORing in something in the bottom 16 bits, we get the base address of the kernel by doing a load from the paca and add an offset. This also replaces an mfmsr and an ori to compute the MSR value for the handler with a load from the paca. That makes it unnecessary to have a separate version of EXCEPTION_PROLOG_PSERIES that forces 64-bit mode. We can no longer use a direct branches in the exception prolog code, which means that the SLB miss handlers can't branch directly to .slb_miss_realmode any more. Instead we have to compute the address and do an indirect branch. This is conditional on CONFIG_RELOCATABLE; for non-relocatable kernels we use a direct branch as before. (A later change will allow CONFIG_RELOCATABLE to be set on 64-bit powerpc.) Since the secondary CPUs on pSeries start execution in the first 0x100 bytes of real memory and then have to get to wherever the kernel is, we can't use a direct branch to get there. Instead this changes __secondary_hold_spinloop from a flag to a function pointer. When it is set to a non-NULL value, the secondary CPUs jump to the function pointed to by that value. Finally this eliminates one code difference between 32-bit and 64-bit by making __secondary_hold be the text address of the secondary CPU spinloop rather than a function descriptor for it. Signed-off-by: Paul Mackerras <paulus@samba.org>
* powerpc: Introduce VSX thread_struct and CONFIG_VSXMichael Neuling2008-07-011-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The layout of the new VSR registers and how they overlap on top of the legacy FPR and VR registers is: VSR doubleword 0 VSR doubleword 1 ---------------------------------------------------------------- VSR[0] | FPR[0] | | ---------------------------------------------------------------- VSR[1] | FPR[1] | | ---------------------------------------------------------------- | ... | | | ... | | ---------------------------------------------------------------- VSR[30] | FPR[30] | | ---------------------------------------------------------------- VSR[31] | FPR[31] | | ---------------------------------------------------------------- VSR[32] | VR[0] | ---------------------------------------------------------------- VSR[33] | VR[1] | ---------------------------------------------------------------- | ... | | ... | ---------------------------------------------------------------- VSR[62] | VR[30] | ---------------------------------------------------------------- VSR[63] | VR[31] | ---------------------------------------------------------------- VSX has 64 128bit registers. The first 32 regs overlap with the FP registers and hence extend them with and additional 64 bits. The second 32 regs overlap with the VMX registers. This commit introduces the thread_struct changes required to reflect this register layout. Ptrace and signals code is updated so that the floating point registers are correctly accessed from the thread_struct when CONFIG_VSX is enabled. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
* [POWERPC] 40x/Book-E: Save/restore volatile exception registersKumar Gala2008-06-021-0/+23
| | | | | | | | | | | | | | | | | | | | | On machines with more than one exception level any system register that might be modified by the "normal" exception level needs to be saved and restored on taking a higher level exception. We already are saving and restoring ESR and DEAR. For critical level add SRR0/1. For debug level add CSRR0/1 and SRR0/1. For machine check level add DSRR0/1, CSRR0/1, and SRR0/1. On FSL Book-E parts we always save/restore the MAS registers for critical, debug, and machine check level exceptions. On 44x we always save/restore the MMUCR. Additionally, we save and restore the ksp_limit since we have to adjust it for each exception level. Signed-off-by: Kumar Gala <galak@kernel.crashing.org> Acked-by: Paul Mackerras <paulus@samba.org>
* Merge branch 'master' of ↵Linus Torvalds2008-04-291-0/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc * 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: [RAPIDIO] Change RapidIO doorbell source and target ID field to 16-bit [RAPIDIO] Add RapidIO connection info print out and re-training for broken connections [RAPIDIO] Add serial RapidIO controller support, which includes MPC8548, MPC8641 [RAPIDIO] Add RapidIO node probing into MPC86xx_HPCN board id table [RAPIDIO] Add RapidIO node into MPC8641HPCN dts file [RAPIDIO] Auto-probe the RapidIO system size [RAPIDIO] Add OF-tree support to RapidIO controller driver [RAPIDIO] Add RapidIO multi mport support [RAPIDIO] Move include/asm-ppc/rio.h to asm-powerpc [RAPIDIO] Add RapidIO option to kernel configuration [RAPIDIO] Change RIO function mpc85xx_ to fsl_ [POWERPC] Provide walk_memory_resource() for powerpc [POWERPC] Update lmb data structures for hotplug memory add/remove [POWERPC] Hotplug memory remove notifications for powerpc [POWERPC] windfarm: Add PowerMac 12,1 support [POWERPC] Fix building of pmac32 when CONFIG_NVRAM=m [POWERPC] Add IRQSTACKS support on ppc32 [POWERPC] Use __always_inline for xchg* and cmpxchg* [POWERPC] Add fast little-endian switch system call
OpenPOWER on IntegriCloud