kernel.git/arch/powerpc/xmon, branch linux-3.7.y

powerpc: Add an xmon command to dump one or all pacas

2012-09-18T05:02:36Z

This was originally motivated by a desire to see the mapping between logical and hardware cpu numbers. But it seemed that it made more sense to just add a command to dump (most of) the paca. With no arguments "dp" will dump the paca for the current cpu. It also takes an argument, eg. "dp 3" which is the logical cpu number in hex. This form does not check if the cpu is possible, but displays the paca regardless, as well as the cpu's state in the possible, present and online masks. Thirdly, "dpa" will display the paca for all possible cpus. If there are no possible cpus, like early in boot, it will tell you that. Sample output, number in brackets is the offset into the struct: 2:mon> dp 3 paca for cpu 0x3 @ c00000000ff20a80: possible = yes present = yes online = yes lock_token = 0x8000 (0x8) paca_index = 0x3 (0xa) kernel_toc = 0xc00000000144f990 (0x10) kernelbase = 0xc000000000000000 (0x18) kernel_msr = 0xb000000000001032 (0x20) stab_real = 0x0 (0x28) stab_addr = 0x0 (0x30) emergency_sp = 0xc00000003ffe4000 (0x38) data_offset = 0xa40000 (0x40) hw_cpu_id = 0x9 (0x50) cpu_start = 0x1 (0x52) kexec_state = 0x0 (0x53) __current = 0xc00000007e568680 (0x218) kstack = 0xc00000007e5a3e30 (0x220) stab_rr = 0x1a (0x228) saved_r1 = 0xc00000007e7cb450 (0x230) trap_save = 0x0 (0x240) soft_enabled = 0x0 (0x242) irq_happened = 0x0 (0x243) io_sync = 0x0 (0x244) irq_work_pending = 0x0 (0x245) nap_state_lost = 0x0 (0x246) Signed-off-by: Michael Ellerman Signed-off-by: Benjamin Herrenschmidt

powerpc: Rework set_dabr so it can take a DABRX value as well

2012-09-09T23:59:10Z

Rework set_dabr to take a DABRX value as well. Both the pseries and PS3 hypervisors do some checks on the DABRX values that are passed in the hcall. This patch stops bogus values from being passed to hypervisor. Also, in the case where we are clearing the breakpoint, where DABR and DABRX are zero, we modify the DABRX value to make it valid so that the hcall won't fail. Signed-off-by: Michael Neuling Signed-off-by: Benjamin Herrenschmidt

powerpc: Fixup whitespace in xmon

2012-08-24T10:26:03Z

There are a few whitespace goolies in xmon.c, some of them appear to be my fault. Fix them all in one go. Signed-off-by: Michael Ellerman Signed-off-by: Benjamin Herrenschmidt

powerpc: Fix xmon dl command for new printk implementation

2012-08-24T10:26:03Z

Since the printk internals were reworked the xmon 'dl' command which dumps the content of __log_buf has stopped working. It is now a structured buffer, so just dumping it doesn't really work. Use the helpers added for kgdb to print out the content. Signed-off-by: Michael Ellerman Signed-off-by: Benjamin Herrenschmidt

powerpc/xmon: Use cpumask iterator to avoid warning

2012-07-02T04:30:11Z

We have a bug report where the kernel hits a warning in the cpumask code: WARNING: at include/linux/cpumask.h:107 Which is: WARN_ON_ONCE(cpu >= nr_cpumask_bits); The backtrace is: cpu_cmd cmds xmon_core xmon die xmon is iterating through 0 to NR_CPUS. I'm not sure why we are still open coding this but iterating above nr_cpu_ids is definitely a bug. This patch iterates through all possible cpus, in case we issue a system reset and CPUs in an offline state call in. Perhaps the old code was trying to handle CPUs that were in the partition but were never started (eg kexec into a kernel with an nr_cpus= boot option). They are going to die way before we get into xmon since we haven't set any kernel state up for them. Signed-off-by: Anton Blanchard CC: Signed-off-by: Benjamin Herrenschmidt

Merge tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system

2012-03-28T22:58:21Z

Pull "Disintegrate and delete asm/system.h" from David Howells: "Here are a bunch of patches to disintegrate asm/system.h into a set of separate bits to relieve the problem of circular inclusion dependencies. I've built all the working defconfigs from all the arches that I can and made sure that they don't break. The reason for these patches is that I recently encountered a circular dependency problem that came about when I produced some patches to optimise get_order() by rewriting it to use ilog2(). This uses bitops - and on the SH arch asm/bitops.h drags in asm-generic/get_order.h by a circuituous route involving asm/system.h. The main difficulty seems to be asm/system.h. It holds a number of low level bits with no/few dependencies that are commonly used (eg. memory barriers) and a number of bits with more dependencies that aren't used in many places (eg. switch_to()). These patches break asm/system.h up into the following core pieces: (1) asm/barrier.h Move memory barriers here. This already done for MIPS and Alpha. (2) asm/switch_to.h Move switch_to() and related stuff here. (3) asm/exec.h Move arch_align_stack() here. Other process execution related bits could perhaps go here from asm/processor.h. (4) asm/cmpxchg.h Move xchg() and cmpxchg() here as they're full word atomic ops and frequently used by atomic_xchg() and atomic_cmpxchg(). (5) asm/bug.h Move die() and related bits. (6) asm/auxvec.h Move AT_VECTOR_SIZE_ARCH here. Other arch headers are created as needed on a per-arch basis." Fixed up some conflicts from other header file cleanups and moving code around that has happened in the meantime, so David's testing is somewhat weakened by that. We'll find out anything that got broken and fix it.. * tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system: (38 commits) Delete all instances of asm/system.h Remove all #inclusions of asm/system.h Add #includes needed to permit the removal of asm/system.h Move all declarations of free_initmem() to linux/mm.h Disintegrate asm/system.h for OpenRISC Split arch_align_stack() out from asm-generic/system.h Split the switch_to() wrapper out of asm-generic/system.h Move the asm-generic/system.h xchg() implementation to asm-generic/cmpxchg.h Create asm-generic/barrier.h Make asm-generic/cmpxchg.h #include asm-generic/cmpxchg-local.h Disintegrate asm/system.h for Xtensa Disintegrate asm/system.h for Unicore32 [based on ver #3, changed by gxt] Disintegrate asm/system.h for Tile Disintegrate asm/system.h for Sparc Disintegrate asm/system.h for SH Disintegrate asm/system.h for Score Disintegrate asm/system.h for S390 Disintegrate asm/system.h for PowerPC Disintegrate asm/system.h for PA-RISC Disintegrate asm/system.h for MN10300 ...

Disintegrate asm/system.h for PowerPC

2012-03-28T17:30:02Z

Disintegrate asm/system.h for PowerPC. Signed-off-by: David Howells Acked-by: Benjamin Herrenschmidt cc: linuxppc-dev@lists.ozlabs.org

Merge tag 'bug-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux

2012-03-24T17:08:39Z

Pull cleanup from Paul Gortmaker: "The changes shown here are to unify linux's BUG support under the one file. Due to historical reasons, we have some BUG code in bug.h and some in kernel.h -- i.e. the support for BUILD_BUG in linux/kernel.h predates the addition of linux/bug.h, but old code in kernel.h wasn't moved to bug.h at that time. As a band-aid, kernel.h was including to pseudo link them. This has caused confusion[1] and general yuck/WTF[2] reactions. Here is an example that violates the principle of least surprise: CC lib/string.o lib/string.c: In function 'strlcat': lib/string.c:225:2: error: implicit declaration of function 'BUILD_BUG_ON' make[2]: *** [lib/string.o] Error 1 $ $ grep linux/bug.h lib/string.c #include $ We've included for the BUG infrastructure and yet we still get a compile fail! [We've not kernel.h for BUILD_BUG_ON.] Ugh - very confusing for someone who is new to kernel development. With the above in mind, the goals of this changeset are: 1) find and fix any include/*.h files that were relying on the implicit presence of BUG code. 2) find and fix any C files that were consuming kernel.h and hence relying on implicitly getting some/all BUG code. 3) Move the BUG related code living in kernel.h to 4) remove the asm/bug.h from kernel.h to finally break the chain. During development, the order was more like 3-4, build-test, 1-2. But to ensure that git history for bisect doesn't get needless build failures introduced, the commits have been reorderd to fix the problem areas in advance. [1] https://lkml.org/lkml/2012/1/3/90 [2] https://lkml.org/lkml/2012/1/17/414" Fix up conflicts (new radeon file, reiserfs header cleanups) as per Paul and linux-next. * tag 'bug-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: kernel.h: doesn't explicitly use bug.h, so don't include it. bug: consolidate BUILD_BUG_ON with other bug code BUG: headers with BUG/BUG_ON etc. need linux/bug.h bug.h: add include of it to various implicit C users lib: fix implicit users of kernel.h for TAINT_WARN spinlock: macroize assert_spin_locked to avoid bug.h dependency x86: relocate get/set debugreg fcns to include/asm/debugreg.

powerpc: Remove FW_FEATURE ISERIES from arch code

2012-03-21T00:16:11Z

This is no longer selectable, so just remove all the dependent code. Signed-off-by: Stephen Rothwell Signed-off-by: Benjamin Herrenschmidt

powerpc: Rework lazy-interrupt handling

2012-03-09T02:25:06Z

The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7