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/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* smp.h: PowerPC-specific SMP code.
*
* Original was a copy of sparc smp.h. Now heavily modified
* for PPC.
*
* Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
* Copyright (C) 1996-2001 Cort Dougan <cort@fsmlabs.com>
*/
#ifndef _ASM_POWERPC_SMP_H
#define _ASM_POWERPC_SMP_H
#ifdef __KERNEL__
#include <linux/threads.h>
#include <linux/cpumask.h>
#include <linux/kernel.h>
powerpc: Consolidate ipi message mux and demux Consolidate the mux and demux of ipi messages into smp.c and call a new smp_ops callback to actually trigger the ipi. The powerpc architecture code is optimised for having 4 distinct ipi triggers, which are mapped to 4 distinct messages (ipi many, ipi single, scheduler ipi, and enter debugger). However, several interrupt controllers only provide a single software triggered interrupt that can be delivered to each cpu. To resolve this limitation, each smp_ops implementation created a per-cpu variable that is manipulated with atomic bitops. Since these lines will be contended they are optimialy marked as shared_aligned and take a full cache line for each cpu. Distro kernels may have 2 or 3 of these in their config, each taking per-cpu space even though at most one will be in use. This consolidation removes smp_message_recv and replaces the single call actions cases with direct calls from the common message recognition loop. The complicated debugger ipi case with its muxed crash handling code is moved to debug_ipi_action which is now called from the demux code (instead of the multi-message action calling smp_message_recv). I put a call to reschedule_action to increase the likelyhood of correctly merging the anticipated scheduler_ipi() hook coming from the scheduler tree; that single required call can be inlined later. The actual message decode is a copy of the old pseries xics code with its memory barriers and cache line spacing, augmented with a per-cpu unsigned long based on the book-e doorbell code. The optional data is set via a callback from the implementation and is passed to the new cause-ipi hook along with the logical cpu number. While currently only the doorbell implemntation uses this data it should be almost zero cost to retrieve and pass it -- it adds a single register load for the argument from the same cache line to which we just completed a store and the register is dead on return from the call. I extended the data element from unsigned int to unsigned long in case some other code wanted to associate a pointer. The doorbell check_self is replaced by a call to smp_muxed_ipi_resend, conditioned on the CPU_DBELL feature. The ifdef guard could be relaxed to CONFIG_SMP but I left it with BOOKE for now. Also, the doorbell interrupt vector for book-e was not calling irq_enter and irq_exit, which throws off cpu accounting and causes code to not realize it is running in interrupt context. Add the missing calls. Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-10 19:29:39 +00:00
#include <linux/irqreturn.h>
#ifndef __ASSEMBLY__
#ifdef CONFIG_PPC64
#include <asm/paca.h>
#endif
#include <asm/percpu.h>
extern int boot_cpuid;
extern int spinning_secondaries;
extern u32 *cpu_to_phys_id;
extern bool coregroup_enabled;
extern int cpu_to_chip_id(int cpu);
extern int *chip_id_lookup_table;
powerpc/cacheinfo: Lookup cache by dt node and thread-group id Currently the cacheinfo code on powerpc indexes the "cache" objects (modelling the L1/L2/L3 caches) where the key is device-tree node corresponding to that cache. On some of the POWER server platforms thread-groups within the core share different sets of caches (Eg: On SMT8 POWER9 systems, threads 0,2,4,6 of a core share L1 cache and threads 1,3,5,7 of the same core share another L1 cache). On such platforms, there is a single device-tree node corresponding to that cache and the cache-configuration within the threads of the core is indicated via "ibm,thread-groups" device-tree property. Since the current code is not aware of the "ibm,thread-groups" property, on the aforementoined systems, cacheinfo code still treats all the threads in the core to be sharing the cache because of the single device-tree node (In the earlier example, the cacheinfo code would says CPUs 0-7 share L1 cache). In this patch, we make the powerpc cacheinfo code aware of the "ibm,thread-groups" property. We indexe the "cache" objects by the key-pair (device-tree node, thread-group id). For any CPUX, for a given level of cache, the thread-group id is defined to be the first CPU in the "ibm,thread-groups" cache-group containing CPUX. For levels of cache which are not represented in "ibm,thread-groups" property, the thread-group id is -1. [parth: Remove "static" keyword for the definition of "thread_group_l1_cache_map" and "thread_group_l2_cache_map" to get rid of the compile error.] Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Parth Shah <parth@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210728175607.591679-2-parth@linux.ibm.com
2021-07-28 23:26:05 +05:30
DECLARE_PER_CPU(cpumask_var_t, thread_group_l1_cache_map);
DECLARE_PER_CPU(cpumask_var_t, thread_group_l2_cache_map);
DECLARE_PER_CPU(cpumask_var_t, thread_group_l3_cache_map);
powerpc/cacheinfo: Lookup cache by dt node and thread-group id Currently the cacheinfo code on powerpc indexes the "cache" objects (modelling the L1/L2/L3 caches) where the key is device-tree node corresponding to that cache. On some of the POWER server platforms thread-groups within the core share different sets of caches (Eg: On SMT8 POWER9 systems, threads 0,2,4,6 of a core share L1 cache and threads 1,3,5,7 of the same core share another L1 cache). On such platforms, there is a single device-tree node corresponding to that cache and the cache-configuration within the threads of the core is indicated via "ibm,thread-groups" device-tree property. Since the current code is not aware of the "ibm,thread-groups" property, on the aforementoined systems, cacheinfo code still treats all the threads in the core to be sharing the cache because of the single device-tree node (In the earlier example, the cacheinfo code would says CPUs 0-7 share L1 cache). In this patch, we make the powerpc cacheinfo code aware of the "ibm,thread-groups" property. We indexe the "cache" objects by the key-pair (device-tree node, thread-group id). For any CPUX, for a given level of cache, the thread-group id is defined to be the first CPU in the "ibm,thread-groups" cache-group containing CPUX. For levels of cache which are not represented in "ibm,thread-groups" property, the thread-group id is -1. [parth: Remove "static" keyword for the definition of "thread_group_l1_cache_map" and "thread_group_l2_cache_map" to get rid of the compile error.] Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Parth Shah <parth@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210728175607.591679-2-parth@linux.ibm.com
2021-07-28 23:26:05 +05:30
#ifdef CONFIG_SMP
struct smp_ops_t {
void (*message_pass)(int cpu, int msg);
#ifdef CONFIG_PPC_SMP_MUXED_IPI
void (*cause_ipi)(int cpu);
#endif
int (*cause_nmi_ipi)(int cpu);
void (*probe)(void);
int (*kick_cpu)(int nr);
int (*prepare_cpu)(int nr);
void (*setup_cpu)(int nr);
void (*bringup_done)(void);
void (*take_timebase)(void);
void (*give_timebase)(void);
int (*cpu_disable)(void);
void (*cpu_die)(unsigned int nr);
int (*cpu_bootable)(unsigned int nr);
#ifdef CONFIG_HOTPLUG_CPU
void (*cpu_offline_self)(void);
#endif
};
extern struct task_struct *secondary_current;
void start_secondary(void *unused);
powerpc/64s: implement arch-specific hardlockup watchdog Implement an arch-speicfic watchdog rather than use the perf-based hardlockup detector. The new watchdog takes the soft-NMI directly, rather than going through perf. Perf interrupts are to be made maskable in future, so that would prevent the perf detector from working in those regions. Additionally, implement a SMP based detector where all CPUs watch one another by pinging a shared cpumask. This is because powerpc Book3S does not have a true periodic local NMI, but some platforms do implement a true NMI IPI. If a CPU is stuck with interrupts hard disabled, the soft-NMI watchdog does not work, but the SMP watchdog will. Even on platforms without a true NMI IPI to get a good trace from the stuck CPU, other CPUs will notice the lockup sufficiently to report it and panic. [npiggin@gmail.com: honor watchdog disable at boot/hotplug] Link: http://lkml.kernel.org/r/20170621001346.5bb337c9@roar.ozlabs.ibm.com [npiggin@gmail.com: fix false positive warning at CPU unplug] Link: http://lkml.kernel.org/r/20170630080740.20766-1-npiggin@gmail.com [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/20170616065715.18390-6-npiggin@gmail.com Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Don Zickus <dzickus@redhat.com> Tested-by: Babu Moger <babu.moger@oracle.com> [sparc] Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-12 14:35:52 -07:00
extern int smp_send_nmi_ipi(int cpu, void (*fn)(struct pt_regs *), u64 delay_us);
extern int smp_send_safe_nmi_ipi(int cpu, void (*fn)(struct pt_regs *), u64 delay_us);
extern void smp_send_debugger_break(void);
extern void start_secondary_resume(void);
extern void smp_generic_give_timebase(void);
extern void smp_generic_take_timebase(void);
DECLARE_PER_CPU(unsigned int, cpu_pvr);
#ifdef CONFIG_HOTPLUG_CPU
int generic_cpu_disable(void);
void generic_cpu_die(unsigned int cpu);
void generic_set_cpu_dead(unsigned int cpu);
void generic_set_cpu_up(unsigned int cpu);
int generic_check_cpu_restart(unsigned int cpu);
int is_cpu_dead(unsigned int cpu);
#else
#define generic_set_cpu_up(i) do { } while (0)
#endif
#ifdef CONFIG_PPC64
#define raw_smp_processor_id() (local_paca->paca_index)
#define hard_smp_processor_id() (get_paca()->hw_cpu_id)
#else
/* 32-bit */
extern int smp_hw_index[];
#define raw_smp_processor_id() (current_thread_info()->cpu)
#define hard_smp_processor_id() (smp_hw_index[smp_processor_id()])
static inline int get_hard_smp_processor_id(int cpu)
{
return smp_hw_index[cpu];
}
static inline void set_hard_smp_processor_id(int cpu, int phys)
{
smp_hw_index[cpu] = phys;
}
#endif
DECLARE_PER_CPU(cpumask_var_t, cpu_sibling_map);
DECLARE_PER_CPU(cpumask_var_t, cpu_l2_cache_map);
DECLARE_PER_CPU(cpumask_var_t, cpu_core_map);
DECLARE_PER_CPU(cpumask_var_t, cpu_smallcore_map);
static inline struct cpumask *cpu_sibling_mask(int cpu)
{
return per_cpu(cpu_sibling_map, cpu);
}
powerpc/smp: Reintroduce cpu_core_mask Daniel reported that with Commit 4ca234a9cbd7 ("powerpc/smp: Stop updating cpu_core_mask") QEMU was unable to set single NUMA node SMP topologies such as: -smp 8,maxcpus=8,cores=2,threads=2,sockets=2 i.e he expected 2 sockets in one NUMA node. The above commit helped to reduce boot time on Large Systems for example 4096 vCPU single socket QEMU instance. PAPR is silent on having more than one socket within a NUMA node. cpu_core_mask and cpu_cpu_mask for any CPU would be same unless the number of sockets is different from the number of NUMA nodes. One option is to reintroduce cpu_core_mask but use a slightly different method to arrive at the cpu_core_mask. Previously each CPU's chip-id would be compared with all other CPU's chip-id to verify if both the CPUs were related at the chip level. Now if a CPU 'A' is found related / (unrelated) to another CPU 'B', all the thread siblings of 'A' and thread siblings of 'B' are automatically marked as related / (unrelated). Also if a platform doesn't support ibm,chip-id property, i.e its cpu_to_chip_id returns -1, cpu_core_map holds a copy of cpu_cpu_mask(). Fixes: 4ca234a9cbd7 ("powerpc/smp: Stop updating cpu_core_mask") Reported-by: Daniel Henrique Barboza <danielhb413@gmail.com> Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210415120934.232271-2-srikar@linux.vnet.ibm.com
2021-04-15 17:39:32 +05:30
static inline struct cpumask *cpu_core_mask(int cpu)
{
return per_cpu(cpu_core_map, cpu);
}
static inline struct cpumask *cpu_l2_cache_mask(int cpu)
{
return per_cpu(cpu_l2_cache_map, cpu);
}
static inline struct cpumask *cpu_smallcore_mask(int cpu)
{
return per_cpu(cpu_smallcore_map, cpu);
}
extern int cpu_to_core_id(int cpu);
powerpc/topology: Override cpu_smt_mask On Power9, a pair of SMT4 cores can be presented by the firmware as a SMT8 core for backward compatibility reasons, with the fusion of two SMT4 cores. Powerpc allows LPARs to be live migrated from Power8 to Power9. Existing software developed/configured for Power8, expects to see a SMT8 core. In order to maintain userspace backward compatibility (with Power8 chips in case of Power9) in enterprise Linux systems, the topology_sibling_cpumask has to be set to SMT8 core. cpu_smt_mask() should generally point to the cpu mask of the SMT4 core. Hence override the default cpu_smt_mask() to be powerpc specific allowing for better scheduling behaviour on Power. schbench (latency measured in usecs, so lesser is better) Without patch With patch Latency percentiles (usec) Latency percentiles (usec) 50.0000th: 34 50.0000th: 38 75.0000th: 47 75.0000th: 52 90.0000th: 54 90.0000th: 60 95.0000th: 57 95.0000th: 64 *99.0000th: 62 *99.0000th: 72 99.5000th: 65 99.5000th: 75 99.9000th: 76 99.9000th: 3452 min=0, max=9205 min=0, max=9344 schbench (With Cede disabled) Without patch With patch Latency percentiles (usec) Latency percentiles (usec) 50.0000th: 20 50.0000th: 21 75.0000th: 28 75.0000th: 29 90.0000th: 33 90.0000th: 34 95.0000th: 35 95.0000th: 37 *99.0000th: 40 *99.0000th: 40 99.5000th: 48 99.5000th: 42 99.9000th: 94 99.9000th: 79 min=0, max=791 min=0, max=791 perf bench sched pipe usec/ops : lesser is better Without patch N Min Max Median Avg Stddev 101 5.095113 5.595269 5.204842 5.2298776 0.10762713 5.10 - 5.15 : ################################################## 23% (24) 5.15 - 5.20 : ############################################# 21% (22) 5.20 - 5.25 : ################################################## 23% (24) 5.25 - 5.30 : ######################### 11% (12) 5.30 - 5.35 : ########## 4% (5) 5.35 - 5.40 : ######## 3% (4) 5.40 - 5.45 : ######## 3% (4) 5.45 - 5.50 : #### 1% (2) 5.50 - 5.55 : ## 0% (1) 5.55 - 5.60 : #### 1% (2) With patch N Min Max Median Avg Stddev 101 5.134675 8.524719 5.207658 5.2780985 0.34911969 5.1 - 5.5 : ################################################## 94% (95) 5.5 - 5.8 : ## 3% (4) 5.8 - 6.2 : 0% (1) 6.2 - 6.5 : 6.5 - 6.8 : 6.8 - 7.2 : 7.2 - 7.5 : 7.5 - 7.8 : 7.8 - 8.2 : 8.2 - 8.5 : perf bench sched pipe (cede disabled) usec/ops : lesser is better Without patch N Min Max Median Avg Stddev 101 7.884227 12.576538 7.956474 8.0170722 0.46159054 7.9 - 8.4 : ################################################## 99% (100) 8.4 - 8.8 : 8.8 - 9.3 : 9.3 - 9.8 : 9.8 - 10.2 : 10.2 - 10.7 : 10.7 - 11.2 : 11.2 - 11.6 : 11.6 - 12.1 : 12.1 - 12.6 : With patch N Min Max Median Avg Stddev 101 7.956021 8.217284 8.015615 8.0283866 0.049844967 7.96 - 7.98 : ###################### 12% (13) 7.98 - 8.01 : ################################################## 28% (29) 8.01 - 8.03 : #################################### 20% (21) 8.03 - 8.06 : ######################### 14% (15) 8.06 - 8.09 : ###################### 12% (13) 8.09 - 8.11 : ###### 3% (4) 8.11 - 8.14 : ### 1% (2) 8.14 - 8.17 : ### 1% (2) 8.17 - 8.19 : 8.19 - 8.22 : # 0% (1) Observations: With the patch, the initial run/iteration takes a slight longer time. This can be attributed to the fact that now we pick a CPU from a idle core which could be sleep mode. Once we remove the cede, state the numbers improve in favour of the patch. ebizzy: transactions per second (higher is better) without patch N Min Max Median Avg Stddev 100 1018433 1304470 1193208 1182315.7 60018.733 1018433 - 1047037 : ###### 3% (3) 1047037 - 1075640 : ######## 4% (4) 1075640 - 1104244 : ######## 4% (4) 1104244 - 1132848 : ############### 7% (7) 1132848 - 1161452 : #################################### 17% (17) 1161452 - 1190055 : ########################## 12% (12) 1190055 - 1218659 : ############################################# 21% (21) 1218659 - 1247263 : ################################################## 23% (23) 1247263 - 1275866 : ######## 4% (4) 1275866 - 1304470 : ######## 4% (4) with patch N Min Max Median Avg Stddev 100 967014 1292938 1208819 1185281.8 69815.851 967014 - 999606 : ## 1% (1) 999606 - 1032199 : ## 1% (1) 1032199 - 1064791 : ############ 6% (6) 1064791 - 1097384 : ########## 5% (5) 1097384 - 1129976 : ################## 9% (9) 1129976 - 1162568 : #################### 10% (10) 1162568 - 1195161 : ########################## 13% (13) 1195161 - 1227753 : ############################################ 22% (22) 1227753 - 1260346 : ################################################## 25% (25) 1260346 - 1292938 : ############## 7% (7) Observations: Not much changes, ebizzy is not much impacted. 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/20200807074517.27957-2-srikar@linux.vnet.ibm.com
2020-08-07 13:15:17 +05:30
extern bool has_big_cores;
powerpc/smp: Add support detecting thread-groups sharing L2 cache On POWER systems, groups of threads within a core sharing the L2-cache can be indicated by the "ibm,thread-groups" property array with the identifier "2". This patch adds support for detecting this, and when present, populate the populating the cpu_l2_cache_mask of every CPU to the core-siblings which share L2 with the CPU as specified in the by the "ibm,thread-groups" property array. On a platform with the following "ibm,thread-group" configuration 00000001 00000002 00000004 00000000 00000002 00000004 00000006 00000001 00000003 00000005 00000007 00000002 00000002 00000004 00000000 00000002 00000004 00000006 00000001 00000003 00000005 00000007 Without this patch, the sched-domain hierarchy for CPUs 0,1 would be CPU0 attaching sched-domain(s): domain-0: span=0,2,4,6 level=SMT domain-1: span=0-7 level=CACHE domain-2: span=0-15,24-39,48-55 level=MC domain-3: span=0-55 level=DIE CPU1 attaching sched-domain(s): domain-0: span=1,3,5,7 level=SMT domain-1: span=0-7 level=CACHE domain-2: span=0-15,24-39,48-55 level=MC domain-3: span=0-55 level=DIE The CACHE domain at 0-7 is incorrect since the ibm,thread-groups sub-array [00000002 00000002 00000004 00000000 00000002 00000004 00000006 00000001 00000003 00000005 00000007] indicates that L2 (Property "2") is shared only between the threads of a single group. There are "2" groups of threads where each group contains "4" threads each. The groups being {0,2,4,6} and {1,3,5,7}. With this patch, the sched-domain hierarchy for CPUs 0,1 would be CPU0 attaching sched-domain(s): domain-0: span=0,2,4,6 level=SMT domain-1: span=0-15,24-39,48-55 level=MC domain-2: span=0-55 level=DIE CPU1 attaching sched-domain(s): domain-0: span=1,3,5,7 level=SMT domain-1: span=0-15,24-39,48-55 level=MC domain-2: span=0-55 level=DIE The CACHE domain with span=0,2,4,6 for CPU 0 (span=1,3,5,7 for CPU 1 resp.) gets degenerated into the SMT domain. Furthermore, the last-level-cache domain gets correctly set to the SMT sched-domain. Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1607596739-32439-5-git-send-email-ego@linux.vnet.ibm.com
2020-12-10 16:08:58 +05:30
extern bool thread_group_shares_l2;
extern bool thread_group_shares_l3;
powerpc/topology: Override cpu_smt_mask On Power9, a pair of SMT4 cores can be presented by the firmware as a SMT8 core for backward compatibility reasons, with the fusion of two SMT4 cores. Powerpc allows LPARs to be live migrated from Power8 to Power9. Existing software developed/configured for Power8, expects to see a SMT8 core. In order to maintain userspace backward compatibility (with Power8 chips in case of Power9) in enterprise Linux systems, the topology_sibling_cpumask has to be set to SMT8 core. cpu_smt_mask() should generally point to the cpu mask of the SMT4 core. Hence override the default cpu_smt_mask() to be powerpc specific allowing for better scheduling behaviour on Power. schbench (latency measured in usecs, so lesser is better) Without patch With patch Latency percentiles (usec) Latency percentiles (usec) 50.0000th: 34 50.0000th: 38 75.0000th: 47 75.0000th: 52 90.0000th: 54 90.0000th: 60 95.0000th: 57 95.0000th: 64 *99.0000th: 62 *99.0000th: 72 99.5000th: 65 99.5000th: 75 99.9000th: 76 99.9000th: 3452 min=0, max=9205 min=0, max=9344 schbench (With Cede disabled) Without patch With patch Latency percentiles (usec) Latency percentiles (usec) 50.0000th: 20 50.0000th: 21 75.0000th: 28 75.0000th: 29 90.0000th: 33 90.0000th: 34 95.0000th: 35 95.0000th: 37 *99.0000th: 40 *99.0000th: 40 99.5000th: 48 99.5000th: 42 99.9000th: 94 99.9000th: 79 min=0, max=791 min=0, max=791 perf bench sched pipe usec/ops : lesser is better Without patch N Min Max Median Avg Stddev 101 5.095113 5.595269 5.204842 5.2298776 0.10762713 5.10 - 5.15 : ################################################## 23% (24) 5.15 - 5.20 : ############################################# 21% (22) 5.20 - 5.25 : ################################################## 23% (24) 5.25 - 5.30 : ######################### 11% (12) 5.30 - 5.35 : ########## 4% (5) 5.35 - 5.40 : ######## 3% (4) 5.40 - 5.45 : ######## 3% (4) 5.45 - 5.50 : #### 1% (2) 5.50 - 5.55 : ## 0% (1) 5.55 - 5.60 : #### 1% (2) With patch N Min Max Median Avg Stddev 101 5.134675 8.524719 5.207658 5.2780985 0.34911969 5.1 - 5.5 : ################################################## 94% (95) 5.5 - 5.8 : ## 3% (4) 5.8 - 6.2 : 0% (1) 6.2 - 6.5 : 6.5 - 6.8 : 6.8 - 7.2 : 7.2 - 7.5 : 7.5 - 7.8 : 7.8 - 8.2 : 8.2 - 8.5 : perf bench sched pipe (cede disabled) usec/ops : lesser is better Without patch N Min Max Median Avg Stddev 101 7.884227 12.576538 7.956474 8.0170722 0.46159054 7.9 - 8.4 : ################################################## 99% (100) 8.4 - 8.8 : 8.8 - 9.3 : 9.3 - 9.8 : 9.8 - 10.2 : 10.2 - 10.7 : 10.7 - 11.2 : 11.2 - 11.6 : 11.6 - 12.1 : 12.1 - 12.6 : With patch N Min Max Median Avg Stddev 101 7.956021 8.217284 8.015615 8.0283866 0.049844967 7.96 - 7.98 : ###################### 12% (13) 7.98 - 8.01 : ################################################## 28% (29) 8.01 - 8.03 : #################################### 20% (21) 8.03 - 8.06 : ######################### 14% (15) 8.06 - 8.09 : ###################### 12% (13) 8.09 - 8.11 : ###### 3% (4) 8.11 - 8.14 : ### 1% (2) 8.14 - 8.17 : ### 1% (2) 8.17 - 8.19 : 8.19 - 8.22 : # 0% (1) Observations: With the patch, the initial run/iteration takes a slight longer time. This can be attributed to the fact that now we pick a CPU from a idle core which could be sleep mode. Once we remove the cede, state the numbers improve in favour of the patch. ebizzy: transactions per second (higher is better) without patch N Min Max Median Avg Stddev 100 1018433 1304470 1193208 1182315.7 60018.733 1018433 - 1047037 : ###### 3% (3) 1047037 - 1075640 : ######## 4% (4) 1075640 - 1104244 : ######## 4% (4) 1104244 - 1132848 : ############### 7% (7) 1132848 - 1161452 : #################################### 17% (17) 1161452 - 1190055 : ########################## 12% (12) 1190055 - 1218659 : ############################################# 21% (21) 1218659 - 1247263 : ################################################## 23% (23) 1247263 - 1275866 : ######## 4% (4) 1275866 - 1304470 : ######## 4% (4) with patch N Min Max Median Avg Stddev 100 967014 1292938 1208819 1185281.8 69815.851 967014 - 999606 : ## 1% (1) 999606 - 1032199 : ## 1% (1) 1032199 - 1064791 : ############ 6% (6) 1064791 - 1097384 : ########## 5% (5) 1097384 - 1129976 : ################## 9% (9) 1129976 - 1162568 : #################### 10% (10) 1162568 - 1195161 : ########################## 13% (13) 1195161 - 1227753 : ############################################ 22% (22) 1227753 - 1260346 : ################################################## 25% (25) 1260346 - 1292938 : ############## 7% (7) Observations: Not much changes, ebizzy is not much impacted. 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/20200807074517.27957-2-srikar@linux.vnet.ibm.com
2020-08-07 13:15:17 +05:30
#define cpu_smt_mask cpu_smt_mask
#ifdef CONFIG_SCHED_SMT
static inline const struct cpumask *cpu_smt_mask(int cpu)
{
if (has_big_cores)
return per_cpu(cpu_smallcore_map, cpu);
return per_cpu(cpu_sibling_map, cpu);
}
#endif /* CONFIG_SCHED_SMT */
/* Since OpenPIC has only 4 IPIs, we use slightly different message numbers.
*
* Make sure this matches openpic_request_IPIs in open_pic.c, or what shows up
* in /proc/interrupts will be wrong!!! --Troy */
#define PPC_MSG_CALL_FUNCTION 0
#define PPC_MSG_RESCHEDULE 1
#define PPC_MSG_TICK_BROADCAST 2
#define PPC_MSG_NMI_IPI 3
/* This is only used by the powernv kernel */
#define PPC_MSG_RM_HOST_ACTION 4
#define NMI_IPI_ALL_OTHERS -2
#ifdef CONFIG_NMI_IPI
extern int smp_handle_nmi_ipi(struct pt_regs *regs);
#else
static inline int smp_handle_nmi_ipi(struct pt_regs *regs) { return 0; }
#endif
powerpc: Consolidate ipi message mux and demux Consolidate the mux and demux of ipi messages into smp.c and call a new smp_ops callback to actually trigger the ipi. The powerpc architecture code is optimised for having 4 distinct ipi triggers, which are mapped to 4 distinct messages (ipi many, ipi single, scheduler ipi, and enter debugger). However, several interrupt controllers only provide a single software triggered interrupt that can be delivered to each cpu. To resolve this limitation, each smp_ops implementation created a per-cpu variable that is manipulated with atomic bitops. Since these lines will be contended they are optimialy marked as shared_aligned and take a full cache line for each cpu. Distro kernels may have 2 or 3 of these in their config, each taking per-cpu space even though at most one will be in use. This consolidation removes smp_message_recv and replaces the single call actions cases with direct calls from the common message recognition loop. The complicated debugger ipi case with its muxed crash handling code is moved to debug_ipi_action which is now called from the demux code (instead of the multi-message action calling smp_message_recv). I put a call to reschedule_action to increase the likelyhood of correctly merging the anticipated scheduler_ipi() hook coming from the scheduler tree; that single required call can be inlined later. The actual message decode is a copy of the old pseries xics code with its memory barriers and cache line spacing, augmented with a per-cpu unsigned long based on the book-e doorbell code. The optional data is set via a callback from the implementation and is passed to the new cause-ipi hook along with the logical cpu number. While currently only the doorbell implemntation uses this data it should be almost zero cost to retrieve and pass it -- it adds a single register load for the argument from the same cache line to which we just completed a store and the register is dead on return from the call. I extended the data element from unsigned int to unsigned long in case some other code wanted to associate a pointer. The doorbell check_self is replaced by a call to smp_muxed_ipi_resend, conditioned on the CPU_DBELL feature. The ifdef guard could be relaxed to CONFIG_SMP but I left it with BOOKE for now. Also, the doorbell interrupt vector for book-e was not calling irq_enter and irq_exit, which throws off cpu accounting and causes code to not realize it is running in interrupt context. Add the missing calls. Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-10 19:29:39 +00:00
/* for irq controllers that have dedicated ipis per message (4) */
extern int smp_request_message_ipi(int virq, int message);
extern const char *smp_ipi_name[];
powerpc: Consolidate ipi message mux and demux Consolidate the mux and demux of ipi messages into smp.c and call a new smp_ops callback to actually trigger the ipi. The powerpc architecture code is optimised for having 4 distinct ipi triggers, which are mapped to 4 distinct messages (ipi many, ipi single, scheduler ipi, and enter debugger). However, several interrupt controllers only provide a single software triggered interrupt that can be delivered to each cpu. To resolve this limitation, each smp_ops implementation created a per-cpu variable that is manipulated with atomic bitops. Since these lines will be contended they are optimialy marked as shared_aligned and take a full cache line for each cpu. Distro kernels may have 2 or 3 of these in their config, each taking per-cpu space even though at most one will be in use. This consolidation removes smp_message_recv and replaces the single call actions cases with direct calls from the common message recognition loop. The complicated debugger ipi case with its muxed crash handling code is moved to debug_ipi_action which is now called from the demux code (instead of the multi-message action calling smp_message_recv). I put a call to reschedule_action to increase the likelyhood of correctly merging the anticipated scheduler_ipi() hook coming from the scheduler tree; that single required call can be inlined later. The actual message decode is a copy of the old pseries xics code with its memory barriers and cache line spacing, augmented with a per-cpu unsigned long based on the book-e doorbell code. The optional data is set via a callback from the implementation and is passed to the new cause-ipi hook along with the logical cpu number. While currently only the doorbell implemntation uses this data it should be almost zero cost to retrieve and pass it -- it adds a single register load for the argument from the same cache line to which we just completed a store and the register is dead on return from the call. I extended the data element from unsigned int to unsigned long in case some other code wanted to associate a pointer. The doorbell check_self is replaced by a call to smp_muxed_ipi_resend, conditioned on the CPU_DBELL feature. The ifdef guard could be relaxed to CONFIG_SMP but I left it with BOOKE for now. Also, the doorbell interrupt vector for book-e was not calling irq_enter and irq_exit, which throws off cpu accounting and causes code to not realize it is running in interrupt context. Add the missing calls. Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-10 19:29:39 +00:00
/* for irq controllers with only a single ipi */
extern void smp_muxed_ipi_message_pass(int cpu, int msg);
extern void smp_muxed_ipi_set_message(int cpu, int msg);
powerpc: Consolidate ipi message mux and demux Consolidate the mux and demux of ipi messages into smp.c and call a new smp_ops callback to actually trigger the ipi. The powerpc architecture code is optimised for having 4 distinct ipi triggers, which are mapped to 4 distinct messages (ipi many, ipi single, scheduler ipi, and enter debugger). However, several interrupt controllers only provide a single software triggered interrupt that can be delivered to each cpu. To resolve this limitation, each smp_ops implementation created a per-cpu variable that is manipulated with atomic bitops. Since these lines will be contended they are optimialy marked as shared_aligned and take a full cache line for each cpu. Distro kernels may have 2 or 3 of these in their config, each taking per-cpu space even though at most one will be in use. This consolidation removes smp_message_recv and replaces the single call actions cases with direct calls from the common message recognition loop. The complicated debugger ipi case with its muxed crash handling code is moved to debug_ipi_action which is now called from the demux code (instead of the multi-message action calling smp_message_recv). I put a call to reschedule_action to increase the likelyhood of correctly merging the anticipated scheduler_ipi() hook coming from the scheduler tree; that single required call can be inlined later. The actual message decode is a copy of the old pseries xics code with its memory barriers and cache line spacing, augmented with a per-cpu unsigned long based on the book-e doorbell code. The optional data is set via a callback from the implementation and is passed to the new cause-ipi hook along with the logical cpu number. While currently only the doorbell implemntation uses this data it should be almost zero cost to retrieve and pass it -- it adds a single register load for the argument from the same cache line to which we just completed a store and the register is dead on return from the call. I extended the data element from unsigned int to unsigned long in case some other code wanted to associate a pointer. The doorbell check_self is replaced by a call to smp_muxed_ipi_resend, conditioned on the CPU_DBELL feature. The ifdef guard could be relaxed to CONFIG_SMP but I left it with BOOKE for now. Also, the doorbell interrupt vector for book-e was not calling irq_enter and irq_exit, which throws off cpu accounting and causes code to not realize it is running in interrupt context. Add the missing calls. Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-10 19:29:39 +00:00
extern irqreturn_t smp_ipi_demux(void);
extern irqreturn_t smp_ipi_demux_relaxed(void);
powerpc: Consolidate ipi message mux and demux Consolidate the mux and demux of ipi messages into smp.c and call a new smp_ops callback to actually trigger the ipi. The powerpc architecture code is optimised for having 4 distinct ipi triggers, which are mapped to 4 distinct messages (ipi many, ipi single, scheduler ipi, and enter debugger). However, several interrupt controllers only provide a single software triggered interrupt that can be delivered to each cpu. To resolve this limitation, each smp_ops implementation created a per-cpu variable that is manipulated with atomic bitops. Since these lines will be contended they are optimialy marked as shared_aligned and take a full cache line for each cpu. Distro kernels may have 2 or 3 of these in their config, each taking per-cpu space even though at most one will be in use. This consolidation removes smp_message_recv and replaces the single call actions cases with direct calls from the common message recognition loop. The complicated debugger ipi case with its muxed crash handling code is moved to debug_ipi_action which is now called from the demux code (instead of the multi-message action calling smp_message_recv). I put a call to reschedule_action to increase the likelyhood of correctly merging the anticipated scheduler_ipi() hook coming from the scheduler tree; that single required call can be inlined later. The actual message decode is a copy of the old pseries xics code with its memory barriers and cache line spacing, augmented with a per-cpu unsigned long based on the book-e doorbell code. The optional data is set via a callback from the implementation and is passed to the new cause-ipi hook along with the logical cpu number. While currently only the doorbell implemntation uses this data it should be almost zero cost to retrieve and pass it -- it adds a single register load for the argument from the same cache line to which we just completed a store and the register is dead on return from the call. I extended the data element from unsigned int to unsigned long in case some other code wanted to associate a pointer. The doorbell check_self is replaced by a call to smp_muxed_ipi_resend, conditioned on the CPU_DBELL feature. The ifdef guard could be relaxed to CONFIG_SMP but I left it with BOOKE for now. Also, the doorbell interrupt vector for book-e was not calling irq_enter and irq_exit, which throws off cpu accounting and causes code to not realize it is running in interrupt context. Add the missing calls. Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-10 19:29:39 +00:00
void smp_init_pSeries(void);
void smp_init_cell(void);
void smp_setup_cpu_maps(void);
extern int __cpu_disable(void);
extern void __cpu_die(unsigned int cpu);
#else
/* for UP */
#define hard_smp_processor_id() get_hard_smp_processor_id(0)
#define smp_setup_cpu_maps()
powerpc/smp: Add support detecting thread-groups sharing L2 cache On POWER systems, groups of threads within a core sharing the L2-cache can be indicated by the "ibm,thread-groups" property array with the identifier "2". This patch adds support for detecting this, and when present, populate the populating the cpu_l2_cache_mask of every CPU to the core-siblings which share L2 with the CPU as specified in the by the "ibm,thread-groups" property array. On a platform with the following "ibm,thread-group" configuration 00000001 00000002 00000004 00000000 00000002 00000004 00000006 00000001 00000003 00000005 00000007 00000002 00000002 00000004 00000000 00000002 00000004 00000006 00000001 00000003 00000005 00000007 Without this patch, the sched-domain hierarchy for CPUs 0,1 would be CPU0 attaching sched-domain(s): domain-0: span=0,2,4,6 level=SMT domain-1: span=0-7 level=CACHE domain-2: span=0-15,24-39,48-55 level=MC domain-3: span=0-55 level=DIE CPU1 attaching sched-domain(s): domain-0: span=1,3,5,7 level=SMT domain-1: span=0-7 level=CACHE domain-2: span=0-15,24-39,48-55 level=MC domain-3: span=0-55 level=DIE The CACHE domain at 0-7 is incorrect since the ibm,thread-groups sub-array [00000002 00000002 00000004 00000000 00000002 00000004 00000006 00000001 00000003 00000005 00000007] indicates that L2 (Property "2") is shared only between the threads of a single group. There are "2" groups of threads where each group contains "4" threads each. The groups being {0,2,4,6} and {1,3,5,7}. With this patch, the sched-domain hierarchy for CPUs 0,1 would be CPU0 attaching sched-domain(s): domain-0: span=0,2,4,6 level=SMT domain-1: span=0-15,24-39,48-55 level=MC domain-2: span=0-55 level=DIE CPU1 attaching sched-domain(s): domain-0: span=1,3,5,7 level=SMT domain-1: span=0-15,24-39,48-55 level=MC domain-2: span=0-55 level=DIE The CACHE domain with span=0,2,4,6 for CPU 0 (span=1,3,5,7 for CPU 1 resp.) gets degenerated into the SMT domain. Furthermore, the last-level-cache domain gets correctly set to the SMT sched-domain. Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1607596739-32439-5-git-send-email-ego@linux.vnet.ibm.com
2020-12-10 16:08:58 +05:30
#define thread_group_shares_l2 0
#define thread_group_shares_l3 0
static inline void inhibit_secondary_onlining(void) {}
static inline void uninhibit_secondary_onlining(void) {}
static inline const struct cpumask *cpu_sibling_mask(int cpu)
{
return cpumask_of(cpu);
}
static inline const struct cpumask *cpu_smallcore_mask(int cpu)
{
return cpumask_of(cpu);
}
powerpc/cacheinfo: Print correct cache-sibling map/list for L2 cache On POWER platforms where only some groups of threads within a core share the L2-cache (indicated by the ibm,thread-groups device-tree property), we currently print the incorrect shared_cpu_map/list for L2-cache in the sysfs. This patch reports the correct shared_cpu_map/list on such platforms. Example: On a platform with "ibm,thread-groups" set to 00000001 00000002 00000004 00000000 00000002 00000004 00000006 00000001 00000003 00000005 00000007 00000002 00000002 00000004 00000000 00000002 00000004 00000006 00000001 00000003 00000005 00000007 This indicates that threads {0,2,4,6} in the core share the L2-cache and threads {1,3,5,7} in the core share the L2 cache. However, without the patch, the shared_cpu_map/list for L2 for CPUs 0, 1 is reported in the sysfs as follows: /sys/devices/system/cpu/cpu0/cache/index2/shared_cpu_list:0-7 /sys/devices/system/cpu/cpu0/cache/index2/shared_cpu_map:000000,000000ff /sys/devices/system/cpu/cpu1/cache/index2/shared_cpu_list:0-7 /sys/devices/system/cpu/cpu1/cache/index2/shared_cpu_map:000000,000000ff With the patch, the shared_cpu_map/list for L2 cache for CPUs 0, 1 is correctly reported as follows: /sys/devices/system/cpu/cpu0/cache/index2/shared_cpu_list:0,2,4,6 /sys/devices/system/cpu/cpu0/cache/index2/shared_cpu_map:000000,00000055 /sys/devices/system/cpu/cpu1/cache/index2/shared_cpu_list:1,3,5,7 /sys/devices/system/cpu/cpu1/cache/index2/shared_cpu_map:000000,000000aa This patch also defines cpu_l2_cache_mask() for !CONFIG_SMP case. Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1607596739-32439-6-git-send-email-ego@linux.vnet.ibm.com
2020-12-10 16:08:59 +05:30
static inline const struct cpumask *cpu_l2_cache_mask(int cpu)
{
return cpumask_of(cpu);
}
#endif /* CONFIG_SMP */
#ifdef CONFIG_PPC64
static inline int get_hard_smp_processor_id(int cpu)
{
return paca_ptrs[cpu]->hw_cpu_id;
}
static inline void set_hard_smp_processor_id(int cpu, int phys)
{
paca_ptrs[cpu]->hw_cpu_id = phys;
}
#else
/* 32-bit */
#ifndef CONFIG_SMP
extern int boot_cpuid_phys;
static inline int get_hard_smp_processor_id(int cpu)
{
return boot_cpuid_phys;
}
static inline void set_hard_smp_processor_id(int cpu, int phys)
{
boot_cpuid_phys = phys;
}
#endif /* !CONFIG_SMP */
#endif /* !CONFIG_PPC64 */
#if defined(CONFIG_PPC64) && (defined(CONFIG_SMP) || defined(CONFIG_KEXEC_CORE))
extern void smp_release_cpus(void);
#else
static inline void smp_release_cpus(void) { }
#endif
extern int smt_enabled_at_boot;
extern void smp_mpic_probe(void);
extern void smp_mpic_setup_cpu(int cpu);
extern int smp_generic_kick_cpu(int nr);
extern int smp_generic_cpu_bootable(unsigned int nr);
extern void smp_generic_give_timebase(void);
extern void smp_generic_take_timebase(void);
extern struct smp_ops_t *smp_ops;
extern void arch_send_call_function_single_ipi(int cpu);
extern void arch_send_call_function_ipi_mask(const struct cpumask *mask);
/* Definitions relative to the secondary CPU spin loop
* and entry point. Not all of them exist on both 32 and
* 64-bit but defining them all here doesn't harm
*/
extern void generic_secondary_smp_init(void);
extern unsigned long __secondary_hold_spinloop;
extern unsigned long __secondary_hold_acknowledge;
extern char __secondary_hold;
extern unsigned int booting_thread_hwid;
extern void __early_start(void);
#endif /* __ASSEMBLY__ */
#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_SMP_H) */