kernel/linux.git/arch/powerpc/include/asm/rtas.h, branch linux-5.9.y

powerpc/pseries: remove memory "re-add" implementation

2020-07-16T03:12:40+00:00

dlpar_memory() no longer has any callers which pass PSERIES_HP_ELOG_ACTION_READD. Remove this case and the corresponding unreachable code. Signed-off-by: Nathan Lynch Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200612051238.1007764-17-nathanl@linux.ibm.com

powerpc/rtas: don't online CPUs for partition suspend

2020-07-16T03:12:35+00:00

Partition suspension, used for hibernation and migration, requires that the OS place all but one of the LPAR's processor threads into one of two states prior to calling the ibm,suspend-me RTAS function: * the architected offline state (via RTAS stop-self); or * the H_JOIN hcall, which does not return until the partition resumes execution Using H_CEDE as the offline mode, introduced by commit 3aa565f53c39 ("powerpc/pseries: Add hooks to put the CPU into an appropriate offline state"), means that any threads which are offline from Linux's point of view must be moved to one of those two states before a partition suspension can proceed. This was eventually addressed in commit 120496ac2d2d ("powerpc: Bring all threads online prior to migration/hibernation"), which added code to temporarily bring up any offline processor threads so they can call H_JOIN. Conceptually this is fine, but the implementation has had multiple races with cpu hotplug operations initiated from user space[1][2][3], the error handling is fragile, and it generates user-visible cpu hotplug events which is a lot of noise for a platform feature that's supposed to minimize disruption to workloads. With commit 3aa565f53c39 ("powerpc/pseries: Add hooks to put the CPU into an appropriate offline state") reverted, this code becomes unnecessary, so remove it. Since any offline CPUs now are truly offline from the platform's point of view, it is no longer necessary to bring up CPUs only to have them call H_JOIN and then go offline again upon resuming. Only active threads are required to call H_JOIN; stopped threads can be left alone. [1] commit a6717c01ddc2 ("powerpc/rtas: use device model APIs and serialization during LPM") [2] commit 9fb603050ffd ("powerpc/rtas: retry when cpu offline races with suspend/migration") [3] commit dfd718a2ed1f ("powerpc/rtas: Fix a potential race between CPU-Offline & Migration") Fixes: 120496ac2d2d ("powerpc: Bring all threads online prior to migration/hibernation") Signed-off-by: Nathan Lynch Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200612051238.1007764-3-nathanl@linux.ibm.com

powerpc/rtas: Implement reentrant rtas call

2020-06-02T10:59:08+00:00

Implement rtas_call_reentrant() for reentrant rtas-calls: "ibm,int-on", "ibm,int-off",ibm,get-xive" and "ibm,set-xive". On LoPAPR Version 1.1 (March 24, 2016), from 7.3.10.1 to 7.3.10.4, items 2 and 3 say: 2 - For the PowerPC External Interrupt option: The * call must be reentrant to the number of processors on the platform. 3 - For the PowerPC External Interrupt option: The * argument call buffer for each simultaneous call must be physically unique. So, these rtas-calls can be called in a lockless way, if using a different buffer for each cpu doing such rtas call. For this, it was suggested to add the buffer (struct rtas_args) in the PACA struct, so each cpu can have it's own buffer. The PACA struct received a pointer to rtas buffer, which is allocated in the memory range available to rtas 32-bit. Reentrant rtas calls are useful to avoid deadlocks in crashing, where rtas-calls are needed, but some other thread crashed holding the rtas.lock. This is a backtrace of a deadlock from a kdump testing environment: #0 arch_spin_lock #1 lock_rtas () #2 rtas_call (token=8204, nargs=1, nret=1, outputs=0x0) #3 ics_rtas_mask_real_irq (hw_irq=4100) #4 machine_kexec_mask_interrupts #5 default_machine_crash_shutdown #6 machine_crash_shutdown #7 __crash_kexec #8 crash_kexec #9 oops_end Signed-off-by: Leonardo Bras [mpe: Move under #ifdef PSERIES to avoid build breakage] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200518234245.200672-3-leobras.c@gmail.com

powerpc/rtas: Move type/struct definitions from rtas.h into rtas-types.h

2020-06-02T10:59:08+00:00

In order to get any rtas* struct into other headers, including rtas.h may cause a lot of errors, regarding include dependency needed for inline functions. Create rtas-types.h and move there all type/struct definitions from rtas.h, then include rtas-types.h into rtas.h. Also, as suggested by checkpath.pl, replace uint8_t for u8. Signed-off-by: Leonardo Bras Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200518234245.200672-2-leobras.c@gmail.com

powerpc/hv-24x7: Add rtas call in hv-24x7 driver to get processor details

2020-05-28T13:24:39+00:00

For hv_24x7 socket/chip level events, specific chip-id to which the data requested should be added as part of pmu events. But number of chips/socket in the system details are not exposed. Patch implements read_24x7_sys_info() to get system parameter values like number of sockets, cores per chip and chips per socket. Rtas_call with token "PROCESSOR_MODULE_INFO" is used to get these values. Subsequent patch exports these values via sysfs. Patch also make these parameters default to 1. Signed-off-by: Kajol Jain Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200525104308.9814-3-kjain@linux.ibm.com

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32+00:00

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman

powerpc/pseries: add missing cpumask.h include file

2018-10-26T10:58:58+00:00

Build error is encountered when inlcuding if no explicit or implicit include of cpumask.h exists in the including file. In file included from arch/powerpc/platforms/pseries/hotplug-pci.c:3:0: ./arch/powerpc/include/asm/rtas.h:360:34: error: unknown type name 'cpumask_var_t' extern int rtas_online_cpus_mask(cpumask_var_t cpus); ^ ./arch/powerpc/include/asm/rtas.h:361:35: error: unknown type name 'cpumask_var_t' extern int rtas_offline_cpus_mask(cpumask_var_t cpus); Fixes: 120496ac2d2d ("powerpc: Bring all threads online prior to migration/hibernation") Signed-off-by: Tyrel Datwyler Signed-off-by: Michael Ellerman

powerpc/pseries: PAPR persistent memory support

2018-10-18T13:56:17+00:00

This patch implements support for discovering storage class memory devices at boot and for handling hotplug of new regions via RTAS hotplug events. Signed-off-by: Oliver O'Halloran [mpe: Fix CONFIG_MEMORY_HOTPLUG=n build] Signed-off-by: Michael Ellerman

powerpc/pseries: Display machine check error details.

2018-09-19T11:59:41+00:00

Extract the MCE error details from RTAS extended log and display it to console. With this patch you should now see mce logs like below: [ 142.371818] Severe Machine check interrupt [Recovered] [ 142.371822] NIP [d00000000ca301b8]: init_module+0x1b8/0x338 [bork_kernel] [ 142.371822] Initiator: CPU [ 142.371823] Error type: SLB [Multihit] [ 142.371824] Effective address: d00000000ca70000 Signed-off-by: Mahesh Salgaonkar Signed-off-by: Michael Ellerman

powerpc/pseries: Define MCE error event section.

2018-09-19T11:58:09+00:00

On pseries, the machine check error details are part of RTAS extended event log passed under Machine check exception section. This patch adds the definition of rtas MCE event section and related helper functions. Signed-off-by: Mahesh Salgaonkar Signed-off-by: Michael Ellerman