At memory hot-remove time we can retrieve an LMB's nid from its
corresponding memory_block. There is no need to store the nid
in multiple locations.
Note that lmb_to_memblock() uses find_memory_block() to get the
corresponding memory_block. As find_memory_block() runs in sub-linear
time this approach is negligibly slower than what we do at present.
In exchange for this lookup at hot-remove time we no longer need to
call memory_add_physaddr_to_nid() during drmem_init() for each LMB.
On powerpc, memory_add_physaddr_to_nid() is a linear search, so this
spares us an O(n^2) initialization during boot.
On systems with many LMBs that initialization overhead is palpable and
disruptive. For example, on a box with 249854 LMBs we're seeing
drmem_init() take upwards of 30 seconds to complete:
[ 53.721639] drmem: initializing drmem v2
[ 80.604346] watchdog: BUG: soft lockup - CPU#65 stuck for 23s! [swapper/0:1]
[ 80.604377] Modules linked in:
[ 80.604389] CPU: 65 PID: 1 Comm: swapper/0 Not tainted 5.6.0-rc2+ #4
[ 80.604397] NIP: c0000000000a4980 LR: c0000000000a4940 CTR: 0000000000000000
[ 80.604407] REGS: c0002dbff8493830 TRAP: 0901 Not tainted (5.6.0-rc2+)
[ 80.604412] MSR: 8000000002009033 <SF,VEC,EE,ME,IR,DR,RI,LE> CR: 44000248 XER: 0000000d
[ 80.604431] CFAR: c0000000000a4a38 IRQMASK: 0
[ 80.604431] GPR00: c0000000000a4940 c0002dbff8493ac0 c000000001904400 c0003cfffffede30
[ 80.604431] GPR04: 0000000000000000 c000000000f4095a 000000000000002f 0000000010000000
[ 80.604431] GPR08: c0000bf7ecdb7fb8 c0000bf7ecc2d3c8 0000000000000008 c00c0002fdfb2001
[ 80.604431] GPR12: 0000000000000000 c00000001e8ec200
[ 80.604477] NIP [c0000000000a4980] hot_add_scn_to_nid+0xa0/0x3e0
[ 80.604486] LR [c0000000000a4940] hot_add_scn_to_nid+0x60/0x3e0
[ 80.604492] Call Trace:
[ 80.604498] [c0002dbff8493ac0] [c0000000000a4940] hot_add_scn_to_nid+0x60/0x3e0 (unreliable)
[ 80.604509] [c0002dbff8493b20] [c000000000087c10] memory_add_physaddr_to_nid+0x20/0x60
[ 80.604521] [c0002dbff8493b40] [c0000000010d4880] drmem_init+0x25c/0x2f0
[ 80.604530] [c0002dbff8493c10] [c000000000010154] do_one_initcall+0x64/0x2c0
[ 80.604540] [c0002dbff8493ce0] [c0000000010c4aa0] kernel_init_freeable+0x2d8/0x3a0
[ 80.604550] [c0002dbff8493db0] [c000000000010824] kernel_init+0x2c/0x148
[ 80.604560] [c0002dbff8493e20] [c00000000000b648] ret_from_kernel_thread+0x5c/0x74
[ 80.604567] Instruction dump:
[ 80.604574] 392918e8 e9490000 e90a000a e92a0000 80ea000c 1d080018 3908ffe8 7d094214
[ 80.604586] 7fa94040 419d00dc e9490010 714a0088 <2faa0008> 409e00ac e9490000 7fbe5040
[ 89.047390] drmem: 249854 LMB(s)
With a patched kernel on the same machine we're no longer seeing the
soft lockup. drmem_init() now completes in negligible time, even when
the LMB count is large.
Fixes: b2d3b5ee66 ("powerpc/pseries: Track LMB nid instead of using device tree")
Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com>
Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200811015115.63677-1-cheloha@linux.ibm.com
The only callers of flush_instruction_cache() are:
arch/powerpc/kernel/swsusp_booke.S: bl flush_instruction_cache
arch/powerpc/mm/nohash/40x.c: flush_instruction_cache();
arch/powerpc/mm/nohash/44x.c: flush_instruction_cache();
arch/powerpc/mm/nohash/fsl_booke.c: flush_instruction_cache();
arch/powerpc/platforms/44x/machine_check.c: flush_instruction_cache();
arch/powerpc/platforms/44x/machine_check.c: flush_instruction_cache();
This function is not used by book3s/32, drop it.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/50098f49877cea0f46730a9df82dcabf84160e4b.1597384512.git.christophe.leroy@csgroup.eu
The drmem lmb list can have hundreds of thousands of entries, and
unfortunately lookups take the form of linear searches. As long as
this is the case, traversals have the potential to monopolize the CPU
and provoke lockup reports, workqueue stalls, and the like unless
they explicitly yield.
Rather than placing cond_resched() calls within various
for_each_drmem_lmb() loop blocks in the code, put it in the iteration
expression of the loop macro itself so users can't omit it.
Introduce a drmem_lmb_next() iteration helper function which calls
cond_resched() at a regular interval during array traversal. Each
iteration of the loop in DLPAR code paths can involve around ten RTAS
calls which can each take up to 250us, so this ensures the check is
performed at worst every few milliseconds.
Fixes: 6c6ea53725 ("powerpc/mm: Separate ibm, dynamic-memory data from DT format")
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200813151131.2070161-1-nathanl@linux.ibm.com
The H_GetPerformanceCounterInfo (GPCI) PHYP hypercall has a subcall,
Affinity_Domain_Info_By_Partition, which returns, among other things,
a "partition affinity score" for a given LPAR. This score, a value on
[0-100], represents the processor-memory affinity for the LPAR in
question. A score of 0 indicates the worst possible affinity while a
score of 100 indicates perfect affinity. The score can be used to
reason about performance.
This patch adds the score for the local LPAR to the lparcfg procfile
under a new 'partition_affinity_score' key.
Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com>
Reviewed-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Acked-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200727184605.2945095-2-cheloha@linux.ibm.com
Building with W=1 results in the following warning:
In file included from arch/powerpc/platforms/powernv/vas-fault.c:16:
./arch/powerpc/include/asm/icswx.h:159:1: error: alignment 1 of ‘struct
coprocessor_request_block’ is less than 16 [-Werror=packed-not-aligned]
159 | } __packed;
| ^
./arch/powerpc/include/asm/icswx.h:159:1: error: alignment 1 of ‘struct
coprocessor_request_block’ is less than 16 [-Werror=packed-not-aligned]
./arch/powerpc/include/asm/icswx.h:159:1: error: alignment 1 of ‘struct
coprocessor_request_block’ is less than 16 [-Werror=packed-not-aligned]
./arch/powerpc/include/asm/icswx.h:159:1: error: alignment 1 of ‘struct
coprocessor_request_block’ is less than 16 [-Werror=packed-not-aligned]
cc1: all warnings being treated as errors
This happens because coprocessor_request_block includes several
sub-structures with an alignment specified using the __aligned(XX)
attribute. The problem comes from coprocessor_request_block having the
__packed attribute. Packing the structure causes the preferred alignment of
the nested structures to be ignored and we get the warnings as a result.
This isn't a problem in practice since the struct is defined with explicit
padding in the form of reserved fields, but we'd like to get rid of the
spurious warnings. The simplest solution is to remove the packed attribute
and use a BUILD_BUG_ON() to ensure the struct is the correct (expected by
HW) size compile time.
Also add a __aligned(128) to the request block structure since Book4 for P8
suggests the HW requires it to be aligned to a 128 byte boundary. There's a
similar requirement for P9 since the COPY and PASTE instructions used to
invoke VAS/NX accelerators operates on a cache line boundary.
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200804005410.146094-7-oohall@gmail.com
Comments opening with /** are parsed by kerneldoc and this causes the
following warning to be printed:
arch/powerpc/platforms/powernv/opal-prd.c:31: warning: cannot understand
function prototype: 'struct opal_prd_msg_queue_item '
opal_prd_mesg_queue_item is an internal data structure so there's no real
need for it to be documented at all. Fix up the comment to squash the
warning.
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200804005410.146094-5-oohall@gmail.com
The asm/powernv.h header provides prototypes for functions which need to be
called by non-powernv platform code. Also include it in the powernv.h
that's local to the platform directory to squash some warnings about
non-static functions missing prototypes.
Also include powernv.h since from opal-memcons.c since it has the
prototypes for the memcons wrangling functions which are used for the opal
and ultravisor msglog.
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200804005410.146094-3-oohall@gmail.com
When building with W=1 we get the following warning:
arch/powerpc/platforms/powernv/smp.c: In function ‘pnv_smp_cpu_kill_self’:
arch/powerpc/platforms/powernv/smp.c:276:16: error: suggest braces around
empty body in an ‘if’ statement [-Werror=empty-body]
276 | cpu, srr1);
| ^
cc1: all warnings being treated as errors
The full context is this block:
if (srr1 && !generic_check_cpu_restart(cpu))
DBG("CPU%d Unexpected exit while offline srr1=%lx!\n",
cpu, srr1);
When building with DEBUG undefined DBG() expands to nothing and GCC emits
the warning due to the lack of braces around an empty statement.
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200804005410.146094-2-oohall@gmail.com
Fix gcc '-Wunused-but-set-variable' warning:
arch/powerpc/kernel/fadump.c: In function fadump_update_elfcore_header:
arch/powerpc/kernel/fadump.c:790:17: warning: variable elf set but not used [-Wunused-but-set-variable]
It is introduced by commit ebaeb5ae24 ("fadump:
Convert firmware-assisted cpu state dump data into elf notes."),
but never used, so remove it.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1574144074-142032-2-git-send-email-zhengbin13@huawei.com
Since the interrupt pin for RTC DS1339 is not connected
to the CPU on T1024RDB, remove the interrupt property
from the device tree.
This also fix the following warning for hwclock.util-linux:
$ hwclock.util-linux
hwclock.util-linux: select() to /dev/rtc0
to wait for clock tick timed out
Signed-off-by: Biwen Li <biwen.li@nxp.com>
Acked-by: Li Yang <leoyang.li@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200527034228.23793-2-biwen.li@oss.nxp.com
Since the interrupt pin for RTC DS1374 is not connected
to the CPU on T4240RDB, remove the interrupt property
from the device tree.
This also fix the following warning for hwclock.util-linux:
$ hwclock.util-linux
hwclock.util-linux: select() to /dev/rtc0
to wait for clock tick timed out
Signed-off-by: Biwen Li <biwen.li@nxp.com>
Acked-by: Li Yang <leoyang.li@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200527034228.23793-1-biwen.li@oss.nxp.com
Existing users of ocxl_link_irq_alloc() have been converted to obtain
the trigger page of an interrupt through xive directly, we therefore
have no need to return the trigger page when allocating an interrupt.
It also allows ocxl to use the xive native interface to allocate
interrupts, instead of its custom service.
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200403153838.29224-4-fbarrat@linux.ibm.com
Pull powerpc fixes from Michael Ellerman:
- Add perf support for emitting extended registers for power10.
- A fix for CPU hotplug on pseries, where on large/loaded systems we
may not wait long enough for the CPU to be offlined, leading to
crashes.
- Addition of a raw cputable entry for Power10, which is not required
to boot, but is required to make our PMU setup work correctly in
guests.
- Three fixes for the recent changes on 32-bit Book3S to move modules
into their own segment for strict RWX.
- A fix for a recent change in our powernv PCI code that could lead to
crashes.
- A change to our perf interrupt accounting to avoid soft lockups when
using some events, found by syzkaller.
- A change in the way we handle power loss events from the hypervisor
on pseries. We no longer immediately shut down if we're told we're
running on a UPS.
- A few other minor fixes.
Thanks to Alexey Kardashevskiy, Andreas Schwab, Aneesh Kumar K.V, Anju T
Sudhakar, Athira Rajeev, Christophe Leroy, Frederic Barrat, Greg Kurz,
Kajol Jain, Madhavan Srinivasan, Michael Neuling, Michael Roth,
Nageswara R Sastry, Oliver O'Halloran, Thiago Jung Bauermann,
Vaidyanathan Srinivasan, Vasant Hegde.
* tag 'powerpc-5.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/perf/hv-24x7: Move cpumask file to top folder of hv-24x7 driver
powerpc/32s: Fix module loading failure when VMALLOC_END is over 0xf0000000
powerpc/pseries: Do not initiate shutdown when system is running on UPS
powerpc/perf: Fix soft lockups due to missed interrupt accounting
powerpc/powernv/pci: Fix possible crash when releasing DMA resources
powerpc/pseries/hotplug-cpu: wait indefinitely for vCPU death
powerpc/32s: Fix is_module_segment() when MODULES_VADDR is defined
powerpc/kasan: Fix KASAN_SHADOW_START on BOOK3S_32
powerpc/fixmap: Fix the size of the early debug area
powerpc/pkeys: Fix build error with PPC_MEM_KEYS disabled
powerpc/kernel: Cleanup machine check function declarations
powerpc: Add POWER10 raw mode cputable entry
powerpc/perf: Add extended regs support for power10 platform
powerpc/perf: Add support for outputting extended regs in perf intr_regs
powerpc: Fix P10 PVR revision in /proc/cpuinfo for SMT4 cores
Pull x86 fix from Thomas Gleixner:
"A single fix for x86 which removes the RDPID usage from the paranoid
entry path and unconditionally uses LSL to retrieve the CPU number.
RDPID depends on MSR_TSX_AUX. KVM has an optmization to avoid
expensive MRS read/writes on VMENTER/EXIT. It caches the MSR values
and restores them either when leaving the run loop, on preemption or
when going out to user space. MSR_TSX_AUX is part of that lazy MSR
set, so after writing the guest value and before the lazy restore any
exception using the paranoid entry will read the guest value and use
it as CPU number to retrieve the GSBASE value for the current CPU when
FSGSBASE is enabled. As RDPID is only used in that particular entry
path, there is no reason to burden VMENTER/EXIT with two extra MSR
writes. Remove the RDPID optimization, which is not even backed by
numbers from the paranoid entry path instead"
* tag 'x86-urgent-2020-08-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/entry/64: Do not use RDPID in paranoid entry to accomodate KVM
Pull x86 perf fix from Thomas Gleixner:
"A single update for perf on x86 which has support for the broken down
bandwith counters"
* tag 'perf-urgent-2020-08-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel/uncore: Add BW counters for GT, IA and IO breakdown
Pull EFI fixes from Thomas Gleixner:
- Enforce NX on RO data in mixed EFI mode
- Destroy workqueue in an error handling path to prevent UAF
- Stop argument parser at '--' which is the delimiter for init
- Treat a NULL command line pointer as empty instead of dereferncing it
unconditionally.
- Handle an unterminated command line correctly
- Cleanup the 32bit code leftovers and remove obsolete documentation
* tag 'efi-urgent-2020-08-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Documentation: efi: remove description of efi=old_map
efi/x86: Move 32-bit code into efi_32.c
efi/libstub: Handle unterminated cmdline
efi/libstub: Handle NULL cmdline
efi/libstub: Stop parsing arguments at "--"
efi: add missed destroy_workqueue when efisubsys_init fails
efi/x86: Mark kernel rodata non-executable for mixed mode
Pull entry fix from Thomas Gleixner:
"A single bug fix for the common entry code.
The transcription of the x86 version messed up the reload of the
syscall number from pt_regs after ptrace and seccomp which breaks
syscall number rewriting"
* tag 'core-urgent-2020-08-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
core/entry: Respect syscall number rewrites