- 08 Oct, 2020 8 commits
-
-
Christophe Leroy authored
This config option isn't in any defconfig. The very first versions of Powerpc 601 have a bug which requires additional sync before and/or after some instructions. This was more than 25 years ago and time has come to retire those buggy versions of the 601 from the kernel. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/55b46bff16705b1ae7bf0a60ccd522b1010ebf75.1601362098.git.christophe.leroy@csgroup.eu
-
Christophe Leroy authored
SYNC is usefull for Powerpc 601 only. On everything else, SYNC is empty. Remove it from code that is not made to run on 6xx. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/27951fa6c9a8f80724d1bc81a6117ac32343a55d.1601362098.git.christophe.leroy@csgroup.eu
-
Vaibhav Jain authored
Add NVDIMM_FAMILY_PAPR to the list of valid 'dimm_family_mask' acceptable by papr_scm. This is needed as since commit 92fe2aa8 ("libnvdimm: Validate command family indices") libnvdimm performs a validation of 'nd_cmd_pkg.nd_family' received as part of ND_CMD_CALL processing to ensure only known command families can use the general ND_CMD_CALL pass-through functionality. Without this change the ND_CMD_CALL pass-through targeting NVDIMM_FAMILY_PAPR error out with -EINVAL. Fixes: 92fe2aa8 ("libnvdimm: Validate command family indices") Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200913211904.24472-1-vaibhav@linux.ibm.com
-
Aneesh Kumar K.V authored
Make it consistent with other usages. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201007114836.282468-5-aneesh.kumar@linux.ibm.com
-
Aneesh Kumar K.V authored
Similar to commit 89c140bb ("pseries: Fix 64 bit logical memory block panic") make sure different variables tracking lmb_size are updated to be 64 bit. Fixes: af9d00e9 ("powerpc/mm/radix: Create separate mappings for hot-plugged memory") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201007114836.282468-4-aneesh.kumar@linux.ibm.com
-
Aneesh Kumar K.V authored
Similar to commit 89c140bb ("pseries: Fix 64 bit logical memory block panic") make sure different variables tracking lmb_size are updated to be 64 bit. This was found by code audit. Cc: stable@vger.kernel.org Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201007114836.282468-3-aneesh.kumar@linux.ibm.com
-
Aneesh Kumar K.V authored
Similar to commit 89c140bb ("pseries: Fix 64 bit logical memory block panic") make sure different variables tracking lmb_size are updated to be 64 bit. This was found by code audit. Cc: stable@vger.kernel.org Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@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/20201007114836.282468-2-aneesh.kumar@linux.ibm.com
-
Nicholas Piggin authored
The inline execution path for the hardware assisted branch flush instruction failed to set CTR to the correct value before bcctr, causing a crash when the feature is enabled. Fixes: 4d24e21c ("powerpc/security: Allow for processors that flush the link stack using the special bcctr") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201007080605.64423-1-npiggin@gmail.com
-
- 07 Oct, 2020 7 commits
-
-
Kajol Jain authored
Patch here adds a cpumask attr to hv_gpci pmu along with ABI documentation. Primary use to expose the cpumask is for the perf tool which has the capability to parse the driver sysfs folder and understand the cpumask file. Having cpumask file will reduce the number of perf command line parameters (will avoid "-C" option in the perf tool command line). It can also notify the user which is the current cpu used to retrieve the counter data. command:# cat /sys/devices/hv_gpci/cpumask 0 Signed-off-by: Kajol Jain <kjain@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201003074943.338618-5-kjain@linux.ibm.com
-
Kajol Jain authored
Patch here adds cpu hotplug functions to hv_gpci pmu. A new cpuhp_state "CPUHP_AP_PERF_POWERPC_HV_GPCI_ONLINE" enum is added. The online callback function updates the cpumask only if its empty. As the primary intention of adding hotplug support is to designate a CPU to make HCALL to collect the counter data. The offline function test and clear corresponding cpu in a cpumask and update cpumask to any other active cpu. Signed-off-by: Kajol Jain <kjain@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201003074943.338618-4-kjain@linux.ibm.com
-
Kajol Jain authored
This patch adds ABI documentation for hv-gpci event format. Signed-off-by: Kajol Jain <kjain@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201003074943.338618-3-kjain@linux.ibm.com
-
Kajol Jain authored
This patch adds ABI documentation for hv-24x7 format. Signed-off-by: Kajol Jain <kjain@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201003074943.338618-2-kjain@linux.ibm.com
-
Kajol Jain authored
Commit 9e9f6010 ("powerpc/perf/{hv-gpci, hv-common}: generate requests with counters annotated") adds a framework for defining gpci counters. In this patch, they adds starting_index value as '0xffffffffffffffff'. which is wrong as starting_index is of size 32 bits. Because of this, incase we try to run hv-gpci event we get error. In power9 machine: command#: perf stat -e hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/ -C 0 -I 1000 event syntax error: '..bie_count_and_time_tlbie_instructions_issued/' \___ value too big for format, maximum is 4294967295 This patch fix this issue and changes starting_index value to '0xffffffff' After this patch: command#: perf stat -e hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/ -C 0 -I 1000 1.000085786 1,024 hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/ 2.000287818 1,024 hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/ 2.439113909 17,408 hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/ Fixes: 9e9f6010 ("powerpc/perf/{hv-gpci, hv-common}: generate requests with counters annotated") Signed-off-by: Kajol Jain <kjain@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201003074943.338618-1-kjain@linux.ibm.com
-
Oliver O'Halloran authored
If the RTAS call to query the PE address for a device fails we jump the err: label where an error message is printed along with the return code. However, the printed return code is from the "ret" variable which isn't set at that point since we assigned the result to "addr" instead. Fix this by consistently using the "ret" variable for the result of the RTAS call helpers an dropping the "addr" local variable" Fixes: 98ba956f ("powerpc/pseries/eeh: Rework device EEH PE determination") Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201007040903.819081-2-oohall@gmail.com
-
Oliver O'Halloran authored
The eeh_pe->config_addr field was supposed to be removed in commit 35d64734 ("powerpc/eeh: Clean up PE addressing") which made it largely unused. Finish the job. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201007040903.819081-1-oohall@gmail.com
-
- 06 Oct, 2020 25 commits
-
-
Scott Cheloha authored
During memory hot-add, dlpar_add_lmb() calls memory_add_physaddr_to_nid() to determine which node id (nid) to use when later calling __add_memory(). This is wasteful. On pseries, memory_add_physaddr_to_nid() finds an appropriate nid for a given address by looking up the LMB containing the address and then passing that LMB to of_drconf_to_nid_single() to get the nid. In dlpar_add_lmb() we get this address from the LMB itself. In short, we have a pointer to an LMB and then we are searching for that LMB *again* in order to find its nid. If we call of_drconf_to_nid_single() directly from dlpar_add_lmb() we can skip the redundant lookup. The only error handling we need to duplicate from memory_add_physaddr_to_nid() is the fallback to the default nid when drconf_to_nid_single() returns -1 (NUMA_NO_NODE) or an invalid nid. Skipping the extra lookup makes hot-add operations faster, especially on machines with many LMBs. Consider an LPAR with 126976 LMBs. In one test, hot-adding 126000 LMBs on an upatched kernel took ~3.5 hours while a patched kernel completed the same operation in ~2 hours: Unpatched (12450 seconds): Sep 9 04:06:31 ltc-brazos1 drmgr[810169]: drmgr: -c mem -a -q 126000 Sep 9 04:06:31 ltc-brazos1 kernel: pseries-hotplug-mem: Attempting to hot-add 126000 LMB(s) [...] Sep 9 07:34:01 ltc-brazos1 kernel: pseries-hotplug-mem: Memory at 20000000 (drc index 80000002) was hot-added Patched (7065 seconds): Sep 8 21:49:57 ltc-brazos1 drmgr[877703]: drmgr: -c mem -a -q 126000 Sep 8 21:49:57 ltc-brazos1 kernel: pseries-hotplug-mem: Attempting to hot-add 126000 LMB(s) [...] Sep 8 23:27:42 ltc-brazos1 kernel: pseries-hotplug-mem: Memory at 20000000 (drc index 80000002) was hot-added It should be noted that the speedup grows more substantial when hot-adding LMBs at the end of the drconf range. This is because we are skipping a linear LMB search. To see the distinction, consider smaller hot-add test on the same LPAR. A perf-stat run with 10 iterations showed that hot-adding 4096 LMBs completed less than 1 second faster on a patched kernel: Unpatched: Performance counter stats for 'drmgr -c mem -a -q 4096' (10 runs): 104,753.42 msec task-clock # 0.992 CPUs utilized ( +- 0.55% ) 4,708 context-switches # 0.045 K/sec ( +- 0.69% ) 2,444 cpu-migrations # 0.023 K/sec ( +- 1.25% ) 394 page-faults # 0.004 K/sec ( +- 0.22% ) 445,902,503,057 cycles # 4.257 GHz ( +- 0.55% ) (66.67%) 8,558,376,740 stalled-cycles-frontend # 1.92% frontend cycles idle ( +- 0.88% ) (49.99%) 300,346,181,651 stalled-cycles-backend # 67.36% backend cycles idle ( +- 0.76% ) (50.01%) 258,091,488,691 instructions # 0.58 insn per cycle # 1.16 stalled cycles per insn ( +- 0.22% ) (66.67%) 70,568,169,256 branches # 673.660 M/sec ( +- 0.17% ) (50.01%) 3,100,725,426 branch-misses # 4.39% of all branches ( +- 0.20% ) (49.99%) 105.583 +- 0.589 seconds time elapsed ( +- 0.56% ) Patched: Performance counter stats for 'drmgr -c mem -a -q 4096' (10 runs): 104,055.69 msec task-clock # 0.993 CPUs utilized ( +- 0.32% ) 4,606 context-switches # 0.044 K/sec ( +- 0.20% ) 2,463 cpu-migrations # 0.024 K/sec ( +- 0.93% ) 394 page-faults # 0.004 K/sec ( +- 0.25% ) 442,951,129,921 cycles # 4.257 GHz ( +- 0.32% ) (66.66%) 8,710,413,329 stalled-cycles-frontend # 1.97% frontend cycles idle ( +- 0.47% ) (50.06%) 299,656,905,836 stalled-cycles-backend # 67.65% backend cycles idle ( +- 0.39% ) (50.02%) 252,731,168,193 instructions # 0.57 insn per cycle # 1.19 stalled cycles per insn ( +- 0.20% ) (66.66%) 68,902,851,121 branches # 662.173 M/sec ( +- 0.13% ) (49.94%) 3,100,242,882 branch-misses # 4.50% of all branches ( +- 0.15% ) (49.98%) 104.829 +- 0.325 seconds time elapsed ( +- 0.31% ) This is consistent. An add-by-count hot-add operation adds LMBs greedily, so LMBs near the start of the drconf range are considered first. On an otherwise idle LPAR with so many LMBs we would expect to find the LMBs we need near the start of the drconf range, hence the smaller speedup. Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com> Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200916145122.3408129-1-cheloha@linux.ibm.com
-
Andrew Donnellan authored
Add a selftest to test the basic functionality of CONFIG_RTAS_FILTER. Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com> [mpe: Change rmo_start/end to 32-bit to avoid build errors on ppc64] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200820044512.7543-2-ajd@linux.ibm.com
-
Andrew Donnellan authored
A number of userspace utilities depend on making calls to RTAS to retrieve information and update various things. The existing API through which we expose RTAS to userspace exposes more RTAS functionality than we actually need, through the sys_rtas syscall, which allows root (or anyone with CAP_SYS_ADMIN) to make any RTAS call they want with arbitrary arguments. Many RTAS calls take the address of a buffer as an argument, and it's up to the caller to specify the physical address of the buffer as an argument. We allocate a buffer (the "RMO buffer") in the Real Memory Area that RTAS can access, and then expose the physical address and size of this buffer in /proc/powerpc/rtas/rmo_buffer. Userspace is expected to read this address, poke at the buffer using /dev/mem, and pass an address in the RMO buffer to the RTAS call. However, there's nothing stopping the caller from specifying whatever address they want in the RTAS call, and it's easy to construct a series of RTAS calls that can overwrite arbitrary bytes (even without /dev/mem access). Additionally, there are some RTAS calls that do potentially dangerous things and for which there are no legitimate userspace use cases. In the past, this would not have been a particularly big deal as it was assumed that root could modify all system state freely, but with Secure Boot and lockdown we need to care about this. We can't fundamentally change the ABI at this point, however we can address this by implementing a filter that checks RTAS calls against a list of permitted calls and forces the caller to use addresses within the RMO buffer. The list is based off the list of calls that are used by the librtas userspace library, and has been tested with a number of existing userspace RTAS utilities. For compatibility with any applications we are not aware of that require other calls, the filter can be turned off at build time. Cc: stable@vger.kernel.org Reported-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200820044512.7543-1-ajd@linux.ibm.com
-
Athira Rajeev authored
PMU counter support functions enforces event constraints for group of events to check if all events in a group can be monitored. Incase of event codes using PMC5 and PMC6 ( 500fa and 600f4 respectively ), not all constraints are applicable, say the threshold or sample bits. But current code includes pmc5 and pmc6 in some group constraints (like IC_DC Qualifier bits) which is actually not applicable and hence results in those events not getting counted when scheduled along with group of other events. Patch fixes this by excluding PMC5/6 from constraints which are not relevant for it. Fixes: 7ffd948f ("powerpc/perf: factor out power8 pmu functions") Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com> Reviewed-by: Madhavan Srinivasan <maddy@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1600672204-1610-1-git-send-email-atrajeev@linux.vnet.ibm.com
-
Srikar Dronamraju authored
All threads of a SMT4/SMT8 core can either be part of CPU's coregroup mask or outside the coregroup. Use this relation to reduce the number of iterations needed to find all the CPUs that share the same coregroup Use a temporary mask to iterate through the CPUs that may share coregroup mask. Also instead of setting one CPU at a time into cpu_coregroup_mask, copy the SMT4/SMT8/submask at one shot. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-12-srikar@linux.vnet.ibm.com
-
Srikar Dronamraju authored
Move the logic for updating the coregroup mask of a CPU to its own function. This will help in reworking the updation of coregroup mask in subsequent patch. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-11-srikar@linux.vnet.ibm.com
-
Srikar Dronamraju authored
All threads of a SMT4 core can either be part of this CPU's l2-cache mask or not related to this CPU l2-cache mask. Use this relation to reduce the number of iterations needed to find all the CPUs that share the same l2-cache. Use a temporary mask to iterate through the CPUs that may share l2_cache mask. Also instead of setting one CPU at a time into cpu_l2_cache_mask, copy the SMT4/sub mask at one shot. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-10-srikar@linux.vnet.ibm.com
-
Srikar Dronamraju authored
CACHE and COREGROUP domains are now part of default topology. However on systems that don't support CACHE or COREGROUP, these domains will eventually be degenerated. The degeneration happens per CPU. Do note the current fixup_topology() logic ensures that mask of a domain that is not supported on the current platform is set to the previous domain. Instead of waiting for the scheduler to degenerated try to consolidate based on their masks and sd_flags. This is done just before setting the scheduler topology. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-9-srikar@linux.vnet.ibm.com
-
Srikar Dronamraju authored
Currently on hotplug/hotunplug, CPU iterates through all the CPUs in its core to find threads in its thread group. However this info is already captured in cpu_l1_cache_map. Hence reduce iterations and cleanup add_cpu_to_smallcore_masks function. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-8-srikar@linux.vnet.ibm.com
-
Srikar Dronamraju authored
update_mask_by_l2 is called only once. But it passes cpu_l2_cache_mask as parameter. Instead of passing cpu_l2_cache_mask, use it directly in update_mask_by_l2. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-7-srikar@linux.vnet.ibm.com
-
Srikar Dronamraju authored
All the arch specific topology cpumasks are within a node/DIE. However when setting these per CPU cpumasks, system traverses through all the online CPUs. This is redundant. Reduce the traversal to only CPUs that are online in the node to which the CPU belongs to. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-6-srikar@linux.vnet.ibm.com
-
Srikar Dronamraju authored
While offlining a CPU, system currently iterate through all the CPUs in the DIE to clear sibling, l2_cache and smallcore maps. However if there are more cores in a DIE, system can end up spending more time iterating through CPUs which are completely unrelated. Optimize this by only iterating through smaller but relevant cpumap. If shared_cache is set, cpu_l2_cache_map should be relevant else cpu_sibling_map would be relevant. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-5-srikar@linux.vnet.ibm.com
-
Srikar Dronamraju authored
Now that cpu_core_mask has been removed and topology_core_cpumask has been updated to use cpu_cpu_mask, we no more need get_physical_package_id. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-4-srikar@linux.vnet.ibm.com
-
Srikar Dronamraju authored
Anton Blanchard reported that his 4096 vcpu KVM guest took around 30 minutes to boot. He also analyzed it to the time taken to iterate while setting the cpu_core_mask. Further analysis shows that cpu_core_mask and cpu_cpu_mask for any CPU would be equal on Power. However updating cpu_core_mask took forever to update as its a per cpu cpumask variable. Instead cpu_cpu_mask was a per NODE /per DIE cpumask that was shared by all the respective CPUs. Also cpu_cpu_mask is needed from a scheduler perspective. However cpu_core_map is an exported symbol. Hence stop updating cpu_core_map and make it point to cpu_cpu_mask. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-3-srikar@linux.vnet.ibm.com
-
Srikar Dronamraju authored
On Power, cpu_core_mask and cpu_cpu_mask refer to the same set of CPUs. cpu_cpu_mask is needed by scheduler, hence look at deprecating cpu_core_mask. Before deleting the cpu_core_mask, ensure its only user is moved to cpu_cpu_mask. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200921095653.9701-2-srikar@linux.vnet.ibm.com
-
Gustavo Romero authored
Althought AMR is stashed in the checkpoint area, currently we don't save it to the per thread checkpoint struct after a treclaim and so we don't restore it either from that struct when we trechkpt. As a consequence when the transaction is later rolled back the kernel space AMR value when the trechkpt was done appears in userspace. That commit saves and restores AMR accordingly on treclaim and trechkpt. Since AMR value is also used in kernel space in other functions, it also takes care of stashing kernel live AMR into the stack before treclaim and before trechkpt, restoring it later, just before returning from tm_reclaim and __tm_recheckpoint. Is also fixes two nonrelated comments about CR and MSR. Signed-off-by: Gustavo Romero <gromero@linux.ibm.com> Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200919150025.9609-1-gromero@linux.ibm.com
-
Oliver O'Halloran authored
When support for EEH on PowerNV was added a lot of pseries specific code was made "generic" and some of the quirks of pseries EEH came along for the ride. One of the stranger quirks is eeh_pe containing two types of PE address: pe->addr and pe->config_addr. There reason for this appears to be historical baggage rather than any real requirements. On pseries EEH PEs are manipulated using RTAS calls. Each EEH RTAS call takes a "PE configuration address" as an input which is used to identify which EEH PE is being manipulated by the call. When initialising the EEH state for a device the first thing we need to do is determine the configuration address for the PE which contains the device so we can enable EEH on that PE. This process is outlined in PAPR which is the modern (i.e post-2003) FW specification for pseries. However, EEH support was first described in the pSeries RISC Platform Architecture (RPA) and although they are mostly compatible EEH is one of the areas where they are not. The major difference is that RPA doesn't actually have the concept of a PE. On RPA systems the EEH RTAS calls are done on a per-device basis using the same config_addr that would be passed to the RTAS functions to access PCI config space (e.g. ibm,read-pci-config). The config_addr is not identical since the function and config register offsets of the config_addr must be set to zero. EEH operations being done on a per-device basis doesn't make a whole lot of sense when you consider how EEH was implemented on legacy PCI systems. For legacy PCI(-X) systems EEH was implemented using special PCI-PCI bridges which contained logic to detect errors and freeze the secondary bus when one occurred. This means that the EEH enabled state is shared among all devices behind that EEH bridge. As a result there's no way to implement the per-device control required for the semantics specified by RPA. It can be made to work if we assume that a separate EEH bridge exists for each EEH capable PCI slot and there are no bridges behind those slots. However, RPA also specifies the ibm,configure-bridge RTAS call for re-initalising bridges behind EEH capable slots after they are reset due to an EEH event so that is probably not a valid assumption. This incoherence was fixed in later PAPR, which succeeded RPA. Unfortunately, since Linux EEH support seems to have been implemented based on the RPA spec some of the legacy assumptions were carried over (probably for POWER4 compatibility). The fix made in PAPR was the introduction of the "PE" concept and redefining the EEH RTAS calls (set-eeh-option, reset-slot, etc) to operate on a per-PE basis so all devices behind an EEH bride would share the same EEH state. The "config_addr" argument to the EEH RTAS calls became the "PE_config_addr" and the OS was required to use the ibm,get-config-addr-info RTAS call to find the correct PE address for the device. When support for the new interfaces was added to Linux it was implemented using something like: At probe time: pdn->eeh_config_addr = rtas_config_addr(pdn); pdn->eeh_pe_config_addr = rtas_get_config_addr_info(pdn); When performing an RTAS call: config_addr = pdn->eeh_config_addr; if (pdn->eeh_pe_config_addr) config_addr = pdn->eeh_pe_config_addr; rtas_call(..., config_addr, ...); In other words, if the ibm,get-config-addr-info RTAS call is implemented and returned a valid result we'd use that as the argument to the EEH RTAS calls. If not, Linux would fall back to using the device's config_addr. Over time these addresses have moved around going from pci_dn to eeh_dev and finally into eeh_pe. Today the users look like this: config_addr = pe->config_addr; if (pe->addr) config_addr = pe->addr; rtas_call(..., config_addr, ...); However, considering the EEH core always operates on a per-PE basis and even on pseries the only per-device operation is the initial call to ibm,set-eeh-option I'm not sure if any of this actually works on an RPA system today. It doesn't make much sense to have the fallback address in a generic structure either since the bulk of the code which reference it is in pseries anyway. The EEH core makes a token effort to support looking up a PE using the config_addr by having two arguments to eeh_pe_get(). However, a survey of all the callers to eeh_pe_get() shows that all bar one have the config_addr argument hard-coded to zero.The only caller that doesn't is in eeh_pe_tree_insert() which has: if (!eeh_has_flag(EEH_VALID_PE_ZERO) && !edev->pe_config_addr) return -EINVAL; pe = eeh_pe_get(hose, edev->pe_config_addr, edev->bdfn); The third argument (config_addr) is only used if the second (pe->addr) argument is invalid. The preceding check ensures that the call to eeh_pe_get() will never happen if edev->pe_config_addr is invalid so there is no situation where eeh_pe_get() will search for a PE based on the 3rd argument. The check also means that we'll never insert a PE into the tree where pe_config_addr is zero since EEH_VALID_PE_ZERO is never set on pseries. All the users of the fallback address on pseries never actually use the fallback and all the only caller that supplies something for the config_addr argument to eeh_pe_get() never use it either. It's all dead code. This patch removes the fallback address from eeh_pe since nothing uses it. Specificly, we do this by: 1) Removing pe->config_addr 2) Removing the EEH_VALID_PE_ZERO flag 3) Removing the fallback address argument to eeh_pe_get(). 4) Removing all the checks for pe->addr being zero in the pseries EEH code. This leaves us with PE's only being identified by what's in their pe->addr field and the EEH core relying on the platform to ensure that eeh_dev's are only inserted into the EEH tree if they're actually inside a PE. No functional changes, I hope. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200918093050.37344-9-oohall@gmail.com
-
Oliver O'Halloran authored
There's no real reason why zero can't be a valid PE configuration address. Under qemu each sPAPR PHB (i.e. EEH supporting) has the passed-though devices on bus zero, so the PE address of bus <dddd>:00 should be zero. However, all previous versions of Linux will reject that, so Qemu at least goes out of it's way to avoid it. The Qemu implementation of ibm,get-config-addr-info2 RTAS has the following comment: > /* > * We always have PE address of form "00BB0001". "BB" > * represents the bus number of PE's primary bus. > */ So qemu puts a one into the register portion of the PE's config_addr to avoid it being zero. The whole is pretty silly considering that RTAS will return a negative error code if it can't map the device's config_addr to a PE. This patch fixes Linux to treat zero as a valid PE address. This shouldn't have any real effects due to the Qemu hack mentioned above. And the fact that Linux EEH has worked historically on PowerVM means they never pass through devices on bus zero so we would never see the problem there either. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200918093050.37344-8-oohall@gmail.com
-
Oliver O'Halloran authored
The process Linux uses for determining if a device supports EEH or not appears to be at odds with what PAPR says the OS should be doing. The current flow is something like: 1. Assume pe_config_addr is equal the the device's config_addr. 2. Attempt to enable EEH on that PE 3. Verify EEH was enabled (POWER4 bug workaround) 4. Try find the pe_config_addr using the ibm,get-config-addr-info2 RTAS call. 5. If that fails walk the pci_dn tree upwards trying to find a parent device with EEH support. If we find one then add the device to that PE. The first major problem with this process is that we need the PE config address in step 2) since its needs to be passed to the ibm,set-eeh-option RTAS call when enabling EEH for th PE. We hack around this requirement in by making the assumption in 1) and delay finding the actual PE address until 4). This is fine if: a) The PCI device is the 0th function, and b) The device is on the PE's root bus. Granted, the current sequence does appear to work on most systems even when these conditions are false. At a guess PowerVM's RTAS has workarounds to accommodate Linux's quirks or the RTAS call to enable EEH is treated as no-op on most platforms since EEH is usually enabled by default. However, what is currently implemented is a bit sketch and is downright confusing since it doesn't match up with what what PAPR suggests we should be doing. This patch re-works how we handle EEH init so that we find the PE config address using the ibm,get-config-addr-info2 RTAS call first, then use the found address to finish the EEH init process. It also drops the Power4 workaround since as of commit 471d7ff8 ("powerpc/64s: Remove POWER4 support") the kernel does not support running on a Power4 CPU so there's no need to support the Power4 platform's quirks either. With the patch applied the sequence is now: 1. Find the pe_config_addr from the device using the RTAS call. 2. Enable the PE. 3. Insert the edev into the tree and create an eeh_pe if needed. The other change made here is ignoring unsupported devices entirely. Currently the device's BARs are saved to the eeh_dev even if the device is not part of an EEH PE. Not being part of a PE means that an EEH recovery pass will never see that device so the saving the BARs is pointless. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200918093050.37344-7-oohall@gmail.com
-
Oliver O'Halloran authored
De-duplicate, and fix up the comments, and make the prototype just take a pci_dn since the job of the function is to return the pe_config_addr of the PE which contains a given device. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200918093050.37344-6-oohall@gmail.com
-
Oliver O'Halloran authored
The initialisation of EEH mostly happens in a core_initcall_sync initcall, followed by registering a bus notifier later on in an arch_initcall. Anything involving initcall dependecies is mostly incomprehensible unless you've spent a while staring at code so here's the full sequence: ppc_md.setup_arch <-- pci_controllers are created here ...time passes... core_initcall <-- pci_dns are created from DT nodes core_initcall_sync <-- platforms call eeh_init() postcore_initcall <-- PCI bus type is registered postcore_initcall_sync arch_initcall <-- EEH pci_bus notifier registered subsys_initcall <-- PHBs are scanned here There's no real requirement to do the EEH setup at the core_initcall_sync level. It just needs to be done after pci_dn's are created and before we start scanning PHBs. Simplify the flow a bit by moving the platform EEH inititalisation to an arch_initcall so we can fold the bus notifier registration into eeh_init(). Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200918093050.37344-5-oohall@gmail.com
-
Oliver O'Halloran authored
No longer used since the platforms perform their EEH initialisation before calling eeh_init(). Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200918093050.37344-4-oohall@gmail.com
-
Oliver O'Halloran authored
Fold pseries_eeh_init() into eeh_pseries_init() rather than having eeh_init() call it via eeh_ops->init(). It's simpler and it'll let us delete eeh_ops.init. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200918093050.37344-3-oohall@gmail.com
-
Oliver O'Halloran authored
Fold pnv_eeh_init() into eeh_powernv_init() rather than having eeh_init() call it via eeh_ops->init(). It's simpler and it'll let us delete eeh_ops.init. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200918093050.37344-2-oohall@gmail.com
-
Oliver O'Halloran authored
Drop the EEH register / unregister ops thing and have the platform pass the ops structure into eeh_init() directly. This takes one initcall out of the EEH setup path and it means we're only doing EEH setup on the platforms which actually support it. It's also less code and generally easier to follow. No functional changes. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200918093050.37344-1-oohall@gmail.com
-