[7768b8d] | 1 | //
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| 2 | // Cforall Version 1.0.0 Copyright (C) 2019 University of Waterloo
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| 3 | //
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| 4 | // The contents of this file are covered under the licence agreement in the
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| 5 | // file "LICENCE" distributed with Cforall.
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| 6 | //
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| 7 | // ready_queue.cfa --
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| 8 | //
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| 9 | // Author : Thierry Delisle
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| 10 | // Created On : Mon Nov dd 16:29:18 2019
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| 11 | // Last Modified By :
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| 12 | // Last Modified On :
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| 13 | // Update Count :
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| 14 | //
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| 15 |
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| 16 | #define __cforall_thread__
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[43784ac] | 17 | #define _GNU_SOURCE
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| 18 |
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[1b143de] | 19 | // #define __CFA_DEBUG_PRINT_READY_QUEUE__
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[7768b8d] | 20 |
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[1eb239e4] | 21 |
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[a2a4566] | 22 | // #define USE_RELAXED_FIFO
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[9cc3a18] | 23 | // #define USE_WORK_STEALING
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[6ba6846] | 24 | // #define USE_CPU_WORK_STEALING
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[a2a4566] | 25 | #define USE_AWARE_STEALING
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[9cc3a18] | 26 |
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[7768b8d] | 27 | #include "bits/defs.hfa"
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[12daa43] | 28 | #include "device/cpu.hfa"
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[7768b8d] | 29 | #include "kernel_private.hfa"
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| 30 |
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| 31 | #include "stdlib.hfa"
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[a2a4566] | 32 | #include "limits.hfa"
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[61d7bec] | 33 | #include "math.hfa"
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[7768b8d] | 34 |
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[0ee224b] | 35 | #include <errno.h>
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[04b5cef] | 36 | #include <unistd.h>
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| 37 |
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[0ee224b] | 38 | extern "C" {
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| 39 | #include <sys/syscall.h> // __NR_xxx
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| 40 | }
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| 41 |
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[13c5e19] | 42 | #include "ready_subqueue.hfa"
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| 43 |
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[7768b8d] | 44 | static const size_t cache_line_size = 64;
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| 45 |
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[d2fadeb] | 46 | #if !defined(__CFA_NO_STATISTICS__)
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| 47 | #define __STATS(...) __VA_ARGS__
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| 48 | #else
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| 49 | #define __STATS(...)
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| 50 | #endif
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| 51 |
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[dca5802] | 52 | // No overriden function, no environment variable, no define
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| 53 | // fall back to a magic number
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| 54 | #ifndef __CFA_MAX_PROCESSORS__
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[b388ee81] | 55 | #define __CFA_MAX_PROCESSORS__ 1024
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[dca5802] | 56 | #endif
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[7768b8d] | 57 |
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[a2a4566] | 58 | #if defined(USE_AWARE_STEALING)
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| 59 | #define READYQ_SHARD_FACTOR 2
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| 60 | #define SEQUENTIAL_SHARD 2
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| 61 | #elif defined(USE_CPU_WORK_STEALING)
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[12daa43] | 62 | #define READYQ_SHARD_FACTOR 2
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| 63 | #elif defined(USE_RELAXED_FIFO)
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[9cc3a18] | 64 | #define BIAS 4
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| 65 | #define READYQ_SHARD_FACTOR 4
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[5f6a172] | 66 | #define SEQUENTIAL_SHARD 1
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[9cc3a18] | 67 | #elif defined(USE_WORK_STEALING)
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| 68 | #define READYQ_SHARD_FACTOR 2
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[5f6a172] | 69 | #define SEQUENTIAL_SHARD 2
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[9cc3a18] | 70 | #else
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| 71 | #error no scheduling strategy selected
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| 72 | #endif
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| 73 |
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[e84ab3d] | 74 | static inline struct thread$ * try_pop(struct cluster * cltr, unsigned w __STATS(, __stats_readyQ_pop_t & stats));
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| 75 | static inline struct thread$ * try_pop(struct cluster * cltr, unsigned i, unsigned j __STATS(, __stats_readyQ_pop_t & stats));
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| 76 | static inline struct thread$ * search(struct cluster * cltr);
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[d2fadeb] | 77 | static inline [unsigned, bool] idx_from_r(unsigned r, unsigned preferred);
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[9cc3a18] | 78 |
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[04b5cef] | 79 |
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[dca5802] | 80 | // returns the maximum number of processors the RWLock support
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[7768b8d] | 81 | __attribute__((weak)) unsigned __max_processors() {
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| 82 | const char * max_cores_s = getenv("CFA_MAX_PROCESSORS");
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| 83 | if(!max_cores_s) {
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[504a7dc] | 84 | __cfadbg_print_nolock(ready_queue, "No CFA_MAX_PROCESSORS in ENV\n");
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[dca5802] | 85 | return __CFA_MAX_PROCESSORS__;
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[7768b8d] | 86 | }
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| 87 |
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| 88 | char * endptr = 0p;
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| 89 | long int max_cores_l = strtol(max_cores_s, &endptr, 10);
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| 90 | if(max_cores_l < 1 || max_cores_l > 65535) {
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[504a7dc] | 91 | __cfadbg_print_nolock(ready_queue, "CFA_MAX_PROCESSORS out of range : %ld\n", max_cores_l);
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[dca5802] | 92 | return __CFA_MAX_PROCESSORS__;
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[7768b8d] | 93 | }
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| 94 | if('\0' != *endptr) {
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[504a7dc] | 95 | __cfadbg_print_nolock(ready_queue, "CFA_MAX_PROCESSORS not a decimal number : %s\n", max_cores_s);
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[dca5802] | 96 | return __CFA_MAX_PROCESSORS__;
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[7768b8d] | 97 | }
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| 98 |
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| 99 | return max_cores_l;
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| 100 | }
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| 101 |
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[0ee224b] | 102 | #if defined(CFA_HAVE_LINUX_LIBRSEQ)
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| 103 | // No forward declaration needed
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| 104 | #define __kernel_rseq_register rseq_register_current_thread
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| 105 | #define __kernel_rseq_unregister rseq_unregister_current_thread
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| 106 | #elif defined(CFA_HAVE_LINUX_RSEQ_H)
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[75c7252] | 107 | static void __kernel_raw_rseq_register (void);
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| 108 | static void __kernel_raw_rseq_unregister(void);
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[0ee224b] | 109 |
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| 110 | #define __kernel_rseq_register __kernel_raw_rseq_register
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| 111 | #define __kernel_rseq_unregister __kernel_raw_rseq_unregister
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| 112 | #else
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| 113 | // No forward declaration needed
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| 114 | // No initialization needed
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| 115 | static inline void noop(void) {}
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| 116 |
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| 117 | #define __kernel_rseq_register noop
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| 118 | #define __kernel_rseq_unregister noop
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| 119 | #endif
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| 120 |
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[7768b8d] | 121 | //=======================================================================
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| 122 | // Cluster wide reader-writer lock
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| 123 | //=======================================================================
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[b388ee81] | 124 | void ?{}(__scheduler_RWLock_t & this) {
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[7768b8d] | 125 | this.max = __max_processors();
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| 126 | this.alloc = 0;
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| 127 | this.ready = 0;
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| 128 | this.data = alloc(this.max);
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[c993b15] | 129 | this.write_lock = false;
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[7768b8d] | 130 |
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| 131 | /*paranoid*/ verify(__atomic_is_lock_free(sizeof(this.alloc), &this.alloc));
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| 132 | /*paranoid*/ verify(__atomic_is_lock_free(sizeof(this.ready), &this.ready));
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| 133 |
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| 134 | }
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[b388ee81] | 135 | void ^?{}(__scheduler_RWLock_t & this) {
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[7768b8d] | 136 | free(this.data);
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| 137 | }
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| 138 |
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| 139 |
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| 140 | //=======================================================================
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| 141 | // Lock-Free registering/unregistering of threads
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[c993b15] | 142 | unsigned register_proc_id( void ) with(*__scheduler_lock) {
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[0ee224b] | 143 | __kernel_rseq_register();
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| 144 |
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[c993b15] | 145 | bool * handle = (bool *)&kernelTLS().sched_lock;
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[504a7dc] | 146 |
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[7768b8d] | 147 | // Step - 1 : check if there is already space in the data
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| 148 | uint_fast32_t s = ready;
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| 149 |
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| 150 | // Check among all the ready
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| 151 | for(uint_fast32_t i = 0; i < s; i++) {
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[c993b15] | 152 | bool * volatile * cell = (bool * volatile *)&data[i]; // Cforall is bugged and the double volatiles causes problems
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| 153 | /* paranoid */ verify( handle != *cell );
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| 154 |
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| 155 | bool * null = 0p; // Re-write every loop since compare thrashes it
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| 156 | if( __atomic_load_n(cell, (int)__ATOMIC_RELAXED) == null
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| 157 | && __atomic_compare_exchange_n( cell, &null, handle, false, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST)) {
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| 158 | /* paranoid */ verify(i < ready);
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| 159 | /* paranoid */ verify( (kernelTLS().sched_id = i, true) );
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| 160 | return i;
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[7768b8d] | 161 | }
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| 162 | }
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| 163 |
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[b388ee81] | 164 | if(max <= alloc) abort("Trying to create more than %ud processors", __scheduler_lock->max);
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[7768b8d] | 165 |
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| 166 | // Step - 2 : F&A to get a new spot in the array.
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| 167 | uint_fast32_t n = __atomic_fetch_add(&alloc, 1, __ATOMIC_SEQ_CST);
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[b388ee81] | 168 | if(max <= n) abort("Trying to create more than %ud processors", __scheduler_lock->max);
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[7768b8d] | 169 |
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| 170 | // Step - 3 : Mark space as used and then publish it.
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[c993b15] | 171 | data[n] = handle;
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[fd9b524] | 172 | while() {
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[7768b8d] | 173 | unsigned copy = n;
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| 174 | if( __atomic_load_n(&ready, __ATOMIC_RELAXED) == n
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| 175 | && __atomic_compare_exchange_n(&ready, ©, n + 1, true, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST))
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| 176 | break;
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[fd9b524] | 177 | Pause();
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[7768b8d] | 178 | }
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| 179 |
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| 180 | // Return new spot.
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[c993b15] | 181 | /* paranoid */ verify(n < ready);
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| 182 | /* paranoid */ verify( (kernelTLS().sched_id = n, true) );
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| 183 | return n;
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[7768b8d] | 184 | }
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| 185 |
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[c993b15] | 186 | void unregister_proc_id( unsigned id ) with(*__scheduler_lock) {
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| 187 | /* paranoid */ verify(id < ready);
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| 188 | /* paranoid */ verify(id == kernelTLS().sched_id);
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| 189 | /* paranoid */ verify(data[id] == &kernelTLS().sched_lock);
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| 190 |
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| 191 | bool * volatile * cell = (bool * volatile *)&data[id]; // Cforall is bugged and the double volatiles causes problems
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| 192 |
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| 193 | __atomic_store_n(cell, 0p, __ATOMIC_RELEASE);
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[504a7dc] | 194 |
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[0ee224b] | 195 | __kernel_rseq_unregister();
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[7768b8d] | 196 | }
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| 197 |
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| 198 | //-----------------------------------------------------------------------
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| 199 | // Writer side : acquire when changing the ready queue, e.g. adding more
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| 200 | // queues or removing them.
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[b388ee81] | 201 | uint_fast32_t ready_mutate_lock( void ) with(*__scheduler_lock) {
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[8fc652e0] | 202 | /* paranoid */ verify( ! __preemption_enabled() );
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[62502cc4] | 203 |
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[7768b8d] | 204 | // Step 1 : lock global lock
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| 205 | // It is needed to avoid processors that register mid Critical-Section
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| 206 | // to simply lock their own lock and enter.
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[c993b15] | 207 | __atomic_acquire( &write_lock );
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[7768b8d] | 208 |
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[46bbcaf] | 209 | // Make sure we won't deadlock ourself
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| 210 | // Checking before acquiring the writer lock isn't safe
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| 211 | // because someone else could have locked us.
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| 212 | /* paranoid */ verify( ! kernelTLS().sched_lock );
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| 213 |
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[7768b8d] | 214 | // Step 2 : lock per-proc lock
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| 215 | // Processors that are currently being registered aren't counted
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| 216 | // but can't be in read_lock or in the critical section.
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| 217 | // All other processors are counted
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| 218 | uint_fast32_t s = ready;
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| 219 | for(uint_fast32_t i = 0; i < s; i++) {
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[c993b15] | 220 | volatile bool * llock = data[i];
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| 221 | if(llock) __atomic_acquire( llock );
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[7768b8d] | 222 | }
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| 223 |
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[8fc652e0] | 224 | /* paranoid */ verify( ! __preemption_enabled() );
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[7768b8d] | 225 | return s;
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| 226 | }
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| 227 |
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[b388ee81] | 228 | void ready_mutate_unlock( uint_fast32_t last_s ) with(*__scheduler_lock) {
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[8fc652e0] | 229 | /* paranoid */ verify( ! __preemption_enabled() );
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[62502cc4] | 230 |
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[7768b8d] | 231 | // Step 1 : release local locks
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| 232 | // This must be done while the global lock is held to avoid
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| 233 | // threads that where created mid critical section
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| 234 | // to race to lock their local locks and have the writer
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| 235 | // immidiately unlock them
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| 236 | // Alternative solution : return s in write_lock and pass it to write_unlock
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| 237 | for(uint_fast32_t i = 0; i < last_s; i++) {
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[c993b15] | 238 | volatile bool * llock = data[i];
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| 239 | if(llock) __atomic_store_n(llock, (bool)false, __ATOMIC_RELEASE);
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[7768b8d] | 240 | }
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| 241 |
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| 242 | // Step 2 : release global lock
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[c993b15] | 243 | /*paranoid*/ assert(true == write_lock);
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| 244 | __atomic_store_n(&write_lock, (bool)false, __ATOMIC_RELEASE);
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[62502cc4] | 245 |
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[8fc652e0] | 246 | /* paranoid */ verify( ! __preemption_enabled() );
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[7768b8d] | 247 | }
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| 248 |
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[a2a4566] | 249 | //=======================================================================
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| 250 | // caches handling
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| 251 |
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| 252 | struct __attribute__((aligned(128))) __ready_queue_caches_t {
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| 253 | // Count States:
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| 254 | // - 0 : No one is looking after this cache
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| 255 | // - 1 : No one is looking after this cache, BUT it's not empty
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| 256 | // - 2+ : At least one processor is looking after this cache
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| 257 | volatile unsigned count;
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| 258 | };
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| 259 |
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| 260 | void ?{}(__ready_queue_caches_t & this) { this.count = 0; }
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| 261 | void ^?{}(__ready_queue_caches_t & this) {}
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| 262 |
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| 263 | static inline void depart(__ready_queue_caches_t & cache) {
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| 264 | /* paranoid */ verify( cache.count > 1);
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| 265 | __atomic_fetch_add(&cache.count, -1, __ATOMIC_SEQ_CST);
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| 266 | /* paranoid */ verify( cache.count != 0);
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| 267 | /* paranoid */ verify( cache.count < 65536 ); // This verify assumes no cluster will have more than 65000 kernel threads mapped to a single cache, which could be correct but is super weird.
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| 268 | }
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| 269 |
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| 270 | static inline void arrive(__ready_queue_caches_t & cache) {
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| 271 | // for() {
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| 272 | // unsigned expected = cache.count;
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| 273 | // unsigned desired = 0 == expected ? 2 : expected + 1;
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| 274 | // }
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| 275 | }
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| 276 |
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[7768b8d] | 277 | //=======================================================================
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[9cc3a18] | 278 | // Cforall Ready Queue used for scheduling
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[b798713] | 279 | //=======================================================================
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[a2a4566] | 280 | unsigned long long moving_average(unsigned long long currtsc, unsigned long long instsc, unsigned long long old_avg) {
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| 281 | /* paranoid */ verifyf( currtsc < 45000000000000000, "Suspiciously large current time: %'llu (%llx)\n", currtsc, currtsc );
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| 282 | /* paranoid */ verifyf( instsc < 45000000000000000, "Suspiciously large insert time: %'llu (%llx)\n", instsc, instsc );
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| 283 | /* paranoid */ verifyf( old_avg < 15000000000000, "Suspiciously large previous average: %'llu (%llx)\n", old_avg, old_avg );
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| 284 |
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| 285 | const unsigned long long new_val = currtsc > instsc ? currtsc - instsc : 0;
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| 286 | const unsigned long long total_weight = 16;
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| 287 | const unsigned long long new_weight = 4;
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| 288 | const unsigned long long old_weight = total_weight - new_weight;
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| 289 | const unsigned long long ret = ((new_weight * new_val) + (old_weight * old_avg)) / total_weight;
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| 290 | return ret;
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[089d30c] | 291 | }
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| 292 |
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[b798713] | 293 | void ?{}(__ready_queue_t & this) with (this) {
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[12daa43] | 294 | #if defined(USE_CPU_WORK_STEALING)
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| 295 | lanes.count = cpu_info.hthrd_count * READYQ_SHARD_FACTOR;
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| 296 | lanes.data = alloc( lanes.count );
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| 297 | lanes.tscs = alloc( lanes.count );
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[089d30c] | 298 | lanes.help = alloc( cpu_info.hthrd_count );
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[12daa43] | 299 |
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| 300 | for( idx; (size_t)lanes.count ) {
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| 301 | (lanes.data[idx]){};
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| 302 | lanes.tscs[idx].tv = rdtscl();
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[089d30c] | 303 | lanes.tscs[idx].ma = rdtscl();
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| 304 | }
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| 305 | for( idx; (size_t)cpu_info.hthrd_count ) {
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| 306 | lanes.help[idx].src = 0;
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| 307 | lanes.help[idx].dst = 0;
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| 308 | lanes.help[idx].tri = 0;
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[12daa43] | 309 | }
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| 310 | #else
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[a2a4566] | 311 | lanes.data = 0p;
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| 312 | lanes.tscs = 0p;
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| 313 | lanes.caches = 0p;
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| 314 | lanes.help = 0p;
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| 315 | lanes.count = 0;
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[12daa43] | 316 | #endif
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[b798713] | 317 | }
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| 318 |
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| 319 | void ^?{}(__ready_queue_t & this) with (this) {
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[12daa43] | 320 | #if !defined(USE_CPU_WORK_STEALING)
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| 321 | verify( SEQUENTIAL_SHARD == lanes.count );
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| 322 | #endif
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| 323 |
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[dca5802] | 324 | free(lanes.data);
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[9cc3a18] | 325 | free(lanes.tscs);
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[a2a4566] | 326 | free(lanes.caches);
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[089d30c] | 327 | free(lanes.help);
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[dca5802] | 328 | }
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| 329 |
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[64a7146] | 330 | //-----------------------------------------------------------------------
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[a2a4566] | 331 | #if defined(USE_AWARE_STEALING)
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| 332 | __attribute__((hot)) void push(struct cluster * cltr, struct thread$ * thrd, unpark_hint hint) with (cltr->ready_queue) {
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| 333 | processor * const proc = kernelTLS().this_processor;
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| 334 | const bool external = (!proc) || (cltr != proc->cltr);
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| 335 | const bool remote = hint == UNPARK_REMOTE;
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| 336 |
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| 337 | unsigned i;
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| 338 | if( external || remote ) {
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| 339 | // Figure out where thread was last time and make sure it's valid
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| 340 | /* paranoid */ verify(thrd->preferred >= 0);
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| 341 | if(thrd->preferred * READYQ_SHARD_FACTOR < lanes.count) {
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| 342 | /* paranoid */ verify(thrd->preferred * READYQ_SHARD_FACTOR < lanes.count);
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| 343 | unsigned start = thrd->preferred * READYQ_SHARD_FACTOR;
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| 344 | do {
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| 345 | unsigned r = __tls_rand();
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| 346 | i = start + (r % READYQ_SHARD_FACTOR);
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| 347 | /* paranoid */ verify( i < lanes.count );
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| 348 | // If we can't lock it retry
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| 349 | } while( !__atomic_try_acquire( &lanes.data[i].lock ) );
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| 350 | } else {
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| 351 | do {
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| 352 | i = __tls_rand() % lanes.count;
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| 353 | } while( !__atomic_try_acquire( &lanes.data[i].lock ) );
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| 354 | }
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| 355 | } else {
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| 356 | do {
|
---|
| 357 | unsigned r = proc->rdq.its++;
|
---|
| 358 | i = proc->rdq.id + (r % READYQ_SHARD_FACTOR);
|
---|
| 359 | /* paranoid */ verify( i < lanes.count );
|
---|
| 360 | // If we can't lock it retry
|
---|
| 361 | } while( !__atomic_try_acquire( &lanes.data[i].lock ) );
|
---|
| 362 | }
|
---|
| 363 |
|
---|
| 364 | // Actually push it
|
---|
| 365 | push(lanes.data[i], thrd);
|
---|
| 366 |
|
---|
| 367 | // Unlock and return
|
---|
| 368 | __atomic_unlock( &lanes.data[i].lock );
|
---|
| 369 |
|
---|
| 370 | #if !defined(__CFA_NO_STATISTICS__)
|
---|
| 371 | if(unlikely(external || remote)) __atomic_fetch_add(&cltr->stats->ready.push.extrn.success, 1, __ATOMIC_RELAXED);
|
---|
| 372 | else __tls_stats()->ready.push.local.success++;
|
---|
| 373 | #endif
|
---|
| 374 | }
|
---|
| 375 |
|
---|
| 376 | static inline unsigned long long calc_cutoff(const unsigned long long ctsc, const processor * proc, __ready_queue_t & rdq) {
|
---|
| 377 | unsigned start = proc->rdq.id;
|
---|
| 378 | unsigned long long max = 0;
|
---|
| 379 | for(i; READYQ_SHARD_FACTOR) {
|
---|
| 380 | unsigned long long ptsc = ts(rdq.lanes.data[start + i]);
|
---|
| 381 | if(ptsc != -1ull) {
|
---|
| 382 | /* paranoid */ verify( start + i < rdq.lanes.count );
|
---|
| 383 | unsigned long long tsc = moving_average(ctsc, ptsc, rdq.lanes.tscs[start + i].ma);
|
---|
| 384 | if(tsc > max) max = tsc;
|
---|
| 385 | }
|
---|
| 386 | }
|
---|
| 387 | return (max + 2 * max) / 2;
|
---|
| 388 | }
|
---|
| 389 |
|
---|
| 390 | __attribute__((hot)) struct thread$ * pop_fast(struct cluster * cltr) with (cltr->ready_queue) {
|
---|
| 391 | /* paranoid */ verify( lanes.count > 0 );
|
---|
| 392 | /* paranoid */ verify( kernelTLS().this_processor );
|
---|
| 393 | /* paranoid */ verify( kernelTLS().this_processor->rdq.id < lanes.count );
|
---|
| 394 |
|
---|
| 395 | processor * const proc = kernelTLS().this_processor;
|
---|
| 396 | unsigned this = proc->rdq.id;
|
---|
| 397 | /* paranoid */ verify( this < lanes.count );
|
---|
| 398 | __cfadbg_print_safe(ready_queue, "Kernel : pop from %u\n", this);
|
---|
| 399 |
|
---|
| 400 | // Figure out the current cpu and make sure it is valid
|
---|
| 401 | const int cpu = __kernel_getcpu();
|
---|
| 402 | /* paranoid */ verify(cpu >= 0);
|
---|
| 403 | /* paranoid */ verify(cpu < cpu_info.hthrd_count);
|
---|
| 404 | unsigned this_cache = cpu_info.llc_map[cpu].cache;
|
---|
[0fb3ee5] | 405 |
|
---|
| 406 | // Super important: don't write the same value over and over again
|
---|
| 407 | // We want to maximise our chances that his particular values stays in cache
|
---|
| 408 | if(lanes.caches[this / READYQ_SHARD_FACTOR].id != this_cache)
|
---|
| 409 | __atomic_store_n(&lanes.caches[this / READYQ_SHARD_FACTOR].id, this_cache, __ATOMIC_RELAXED);
|
---|
[a2a4566] | 410 |
|
---|
| 411 | const unsigned long long ctsc = rdtscl();
|
---|
| 412 |
|
---|
| 413 | if(proc->rdq.target == MAX) {
|
---|
| 414 | uint64_t chaos = __tls_rand();
|
---|
| 415 | unsigned ext = chaos & 0xff;
|
---|
| 416 | unsigned other = (chaos >> 8) % (lanes.count);
|
---|
| 417 |
|
---|
| 418 | if(ext < 3 || __atomic_load_n(&lanes.caches[other / READYQ_SHARD_FACTOR].id, __ATOMIC_RELAXED) == this_cache) {
|
---|
| 419 | proc->rdq.target = other;
|
---|
| 420 | }
|
---|
| 421 | }
|
---|
| 422 | else {
|
---|
| 423 | const unsigned target = proc->rdq.target;
|
---|
| 424 | __cfadbg_print_safe(ready_queue, "Kernel : %u considering helping %u, tcsc %llu\n", this, target, lanes.tscs[target].tv);
|
---|
| 425 | /* paranoid */ verify( lanes.tscs[target].tv != MAX );
|
---|
| 426 | if(target < lanes.count) {
|
---|
| 427 | const unsigned long long cutoff = calc_cutoff(ctsc, proc, cltr->ready_queue);
|
---|
| 428 | const unsigned long long age = moving_average(ctsc, lanes.tscs[target].tv, lanes.tscs[target].ma);
|
---|
| 429 | __cfadbg_print_safe(ready_queue, "Kernel : Help attempt on %u from %u, age %'llu vs cutoff %'llu, %s\n", target, this, age, cutoff, age > cutoff ? "yes" : "no");
|
---|
| 430 | if(age > cutoff) {
|
---|
| 431 | thread$ * t = try_pop(cltr, target __STATS(, __tls_stats()->ready.pop.help));
|
---|
| 432 | if(t) return t;
|
---|
| 433 | }
|
---|
| 434 | }
|
---|
| 435 | proc->rdq.target = MAX;
|
---|
| 436 | }
|
---|
| 437 |
|
---|
| 438 | for(READYQ_SHARD_FACTOR) {
|
---|
| 439 | unsigned i = this + (proc->rdq.itr++ % READYQ_SHARD_FACTOR);
|
---|
| 440 | if(thread$ * t = try_pop(cltr, i __STATS(, __tls_stats()->ready.pop.local))) return t;
|
---|
| 441 | }
|
---|
| 442 |
|
---|
| 443 | // All lanes where empty return 0p
|
---|
| 444 | return 0p;
|
---|
| 445 |
|
---|
| 446 | }
|
---|
| 447 | __attribute__((hot)) struct thread$ * pop_slow(struct cluster * cltr) with (cltr->ready_queue) {
|
---|
| 448 | unsigned i = __tls_rand() % lanes.count;
|
---|
| 449 | return try_pop(cltr, i __STATS(, __tls_stats()->ready.pop.steal));
|
---|
| 450 | }
|
---|
| 451 | __attribute__((hot)) struct thread$ * pop_search(struct cluster * cltr) {
|
---|
| 452 | return search(cltr);
|
---|
| 453 | }
|
---|
| 454 | #endif
|
---|
[12daa43] | 455 | #if defined(USE_CPU_WORK_STEALING)
|
---|
[24e321c] | 456 | __attribute__((hot)) void push(struct cluster * cltr, struct thread$ * thrd, unpark_hint hint) with (cltr->ready_queue) {
|
---|
[12daa43] | 457 | __cfadbg_print_safe(ready_queue, "Kernel : Pushing %p on cluster %p\n", thrd, cltr);
|
---|
| 458 |
|
---|
| 459 | processor * const proc = kernelTLS().this_processor;
|
---|
[75c7252] | 460 | const bool external = (!proc) || (cltr != proc->cltr);
|
---|
[12daa43] | 461 |
|
---|
[75c7252] | 462 | // Figure out the current cpu and make sure it is valid
|
---|
[12daa43] | 463 | const int cpu = __kernel_getcpu();
|
---|
| 464 | /* paranoid */ verify(cpu >= 0);
|
---|
| 465 | /* paranoid */ verify(cpu < cpu_info.hthrd_count);
|
---|
| 466 | /* paranoid */ verify(cpu * READYQ_SHARD_FACTOR < lanes.count);
|
---|
| 467 |
|
---|
[75c7252] | 468 | // Figure out where thread was last time and make sure it's
|
---|
| 469 | /* paranoid */ verify(thrd->preferred >= 0);
|
---|
| 470 | /* paranoid */ verify(thrd->preferred < cpu_info.hthrd_count);
|
---|
| 471 | /* paranoid */ verify(thrd->preferred * READYQ_SHARD_FACTOR < lanes.count);
|
---|
| 472 | const int prf = thrd->preferred * READYQ_SHARD_FACTOR;
|
---|
| 473 |
|
---|
| 474 | const cpu_map_entry_t & map;
|
---|
| 475 | choose(hint) {
|
---|
| 476 | case UNPARK_LOCAL : &map = &cpu_info.llc_map[cpu];
|
---|
| 477 | case UNPARK_REMOTE: &map = &cpu_info.llc_map[prf];
|
---|
| 478 | }
|
---|
[df7597e0] | 479 | /* paranoid */ verify(map.start * READYQ_SHARD_FACTOR < lanes.count);
|
---|
| 480 | /* paranoid */ verify(map.self * READYQ_SHARD_FACTOR < lanes.count);
|
---|
[5614552a] | 481 | /* paranoid */ verifyf((map.start + map.count) * READYQ_SHARD_FACTOR <= lanes.count, "have %zu lanes but map can go up to %u", lanes.count, (map.start + map.count) * READYQ_SHARD_FACTOR);
|
---|
[df7597e0] | 482 |
|
---|
| 483 | const int start = map.self * READYQ_SHARD_FACTOR;
|
---|
[12daa43] | 484 | unsigned i;
|
---|
| 485 | do {
|
---|
| 486 | unsigned r;
|
---|
| 487 | if(unlikely(external)) { r = __tls_rand(); }
|
---|
| 488 | else { r = proc->rdq.its++; }
|
---|
[75c7252] | 489 | choose(hint) {
|
---|
| 490 | case UNPARK_LOCAL : i = start + (r % READYQ_SHARD_FACTOR);
|
---|
| 491 | case UNPARK_REMOTE: i = prf + (r % READYQ_SHARD_FACTOR);
|
---|
| 492 | }
|
---|
[12daa43] | 493 | // If we can't lock it retry
|
---|
| 494 | } while( !__atomic_try_acquire( &lanes.data[i].lock ) );
|
---|
| 495 |
|
---|
| 496 | // Actually push it
|
---|
| 497 | push(lanes.data[i], thrd);
|
---|
| 498 |
|
---|
| 499 | // Unlock and return
|
---|
| 500 | __atomic_unlock( &lanes.data[i].lock );
|
---|
| 501 |
|
---|
| 502 | #if !defined(__CFA_NO_STATISTICS__)
|
---|
| 503 | if(unlikely(external)) __atomic_fetch_add(&cltr->stats->ready.push.extrn.success, 1, __ATOMIC_RELAXED);
|
---|
| 504 | else __tls_stats()->ready.push.local.success++;
|
---|
| 505 | #endif
|
---|
| 506 |
|
---|
| 507 | __cfadbg_print_safe(ready_queue, "Kernel : Pushed %p on cluster %p (idx: %u, mask %llu, first %d)\n", thrd, cltr, i, used.mask[0], lane_first);
|
---|
| 508 |
|
---|
| 509 | }
|
---|
| 510 |
|
---|
| 511 | // Pop from the ready queue from a given cluster
|
---|
[e84ab3d] | 512 | __attribute__((hot)) thread$ * pop_fast(struct cluster * cltr) with (cltr->ready_queue) {
|
---|
[12daa43] | 513 | /* paranoid */ verify( lanes.count > 0 );
|
---|
| 514 | /* paranoid */ verify( kernelTLS().this_processor );
|
---|
| 515 |
|
---|
[a2a4566] | 516 | processor * const proc = kernelTLS().this_processor;
|
---|
[25337e0] | 517 | const int cpu = __kernel_getcpu();
|
---|
[12daa43] | 518 | /* paranoid */ verify(cpu >= 0);
|
---|
| 519 | /* paranoid */ verify(cpu < cpu_info.hthrd_count);
|
---|
[df7597e0] | 520 | /* paranoid */ verify(cpu * READYQ_SHARD_FACTOR < lanes.count);
|
---|
| 521 |
|
---|
| 522 | const cpu_map_entry_t & map = cpu_info.llc_map[cpu];
|
---|
| 523 | /* paranoid */ verify(map.start * READYQ_SHARD_FACTOR < lanes.count);
|
---|
| 524 | /* paranoid */ verify(map.self * READYQ_SHARD_FACTOR < lanes.count);
|
---|
[5614552a] | 525 | /* paranoid */ verifyf((map.start + map.count) * READYQ_SHARD_FACTOR <= lanes.count, "have %zu lanes but map can go up to %u", lanes.count, (map.start + map.count) * READYQ_SHARD_FACTOR);
|
---|
[12daa43] | 526 |
|
---|
[df7597e0] | 527 | const int start = map.self * READYQ_SHARD_FACTOR;
|
---|
[089d30c] | 528 | const unsigned long long ctsc = rdtscl();
|
---|
[12daa43] | 529 |
|
---|
| 530 | // Did we already have a help target
|
---|
[a2a4566] | 531 | if(proc->rdq.target == MAX) {
|
---|
[089d30c] | 532 | unsigned long long max = 0;
|
---|
[12daa43] | 533 | for(i; READYQ_SHARD_FACTOR) {
|
---|
[25337e0] | 534 | unsigned long long tsc = moving_average(ctsc, ts(lanes.data[start + i]), lanes.tscs[start + i].ma);
|
---|
[089d30c] | 535 | if(tsc > max) max = tsc;
|
---|
[12daa43] | 536 | }
|
---|
[a2a4566] | 537 | // proc->rdq.cutoff = (max + 2 * max) / 2;
|
---|
[953827a] | 538 | /* paranoid */ verify(lanes.count < 65536); // The following code assumes max 65536 cores.
|
---|
| 539 | /* paranoid */ verify(map.count < 65536); // The following code assumes max 65536 cores.
|
---|
| 540 |
|
---|
[089d30c] | 541 | if(0 == (__tls_rand() % 100)) {
|
---|
[1f45c7d] | 542 | proc->rdq.target = __tls_rand() % lanes.count;
|
---|
[953827a] | 543 | } else {
|
---|
[1f45c7d] | 544 | unsigned cpu_chaos = map.start + (__tls_rand() % map.count);
|
---|
| 545 | proc->rdq.target = (cpu_chaos * READYQ_SHARD_FACTOR) + (__tls_rand() % READYQ_SHARD_FACTOR);
|
---|
[953827a] | 546 | /* paranoid */ verify(proc->rdq.target >= (map.start * READYQ_SHARD_FACTOR));
|
---|
| 547 | /* paranoid */ verify(proc->rdq.target < ((map.start + map.count) * READYQ_SHARD_FACTOR));
|
---|
| 548 | }
|
---|
| 549 |
|
---|
[a2a4566] | 550 | /* paranoid */ verify(proc->rdq.target != MAX);
|
---|
[12daa43] | 551 | }
|
---|
| 552 | else {
|
---|
[089d30c] | 553 | unsigned long long max = 0;
|
---|
| 554 | for(i; READYQ_SHARD_FACTOR) {
|
---|
[25337e0] | 555 | unsigned long long tsc = moving_average(ctsc, ts(lanes.data[start + i]), lanes.tscs[start + i].ma);
|
---|
[089d30c] | 556 | if(tsc > max) max = tsc;
|
---|
| 557 | }
|
---|
| 558 | const unsigned long long cutoff = (max + 2 * max) / 2;
|
---|
[12daa43] | 559 | {
|
---|
| 560 | unsigned target = proc->rdq.target;
|
---|
[a2a4566] | 561 | proc->rdq.target = MAX;
|
---|
[fcd65ca] | 562 | lanes.help[target / READYQ_SHARD_FACTOR].tri++;
|
---|
[25337e0] | 563 | if(moving_average(ctsc, lanes.tscs[target].tv, lanes.tscs[target].ma) > cutoff) {
|
---|
[e84ab3d] | 564 | thread$ * t = try_pop(cltr, target __STATS(, __tls_stats()->ready.pop.help));
|
---|
[12daa43] | 565 | proc->rdq.last = target;
|
---|
| 566 | if(t) return t;
|
---|
| 567 | }
|
---|
[a2a4566] | 568 | proc->rdq.target = MAX;
|
---|
[12daa43] | 569 | }
|
---|
| 570 |
|
---|
| 571 | unsigned last = proc->rdq.last;
|
---|
[25337e0] | 572 | if(last != MAX && moving_average(ctsc, lanes.tscs[last].tv, lanes.tscs[last].ma) > cutoff) {
|
---|
[e84ab3d] | 573 | thread$ * t = try_pop(cltr, last __STATS(, __tls_stats()->ready.pop.help));
|
---|
[12daa43] | 574 | if(t) return t;
|
---|
| 575 | }
|
---|
| 576 | else {
|
---|
[a2a4566] | 577 | proc->rdq.last = MAX;
|
---|
[12daa43] | 578 | }
|
---|
| 579 | }
|
---|
| 580 |
|
---|
| 581 | for(READYQ_SHARD_FACTOR) {
|
---|
| 582 | unsigned i = start + (proc->rdq.itr++ % READYQ_SHARD_FACTOR);
|
---|
[e84ab3d] | 583 | if(thread$ * t = try_pop(cltr, i __STATS(, __tls_stats()->ready.pop.local))) return t;
|
---|
[12daa43] | 584 | }
|
---|
| 585 |
|
---|
| 586 | // All lanes where empty return 0p
|
---|
| 587 | return 0p;
|
---|
| 588 | }
|
---|
| 589 |
|
---|
[e84ab3d] | 590 | __attribute__((hot)) struct thread$ * pop_slow(struct cluster * cltr) with (cltr->ready_queue) {
|
---|
[12daa43] | 591 | processor * const proc = kernelTLS().this_processor;
|
---|
| 592 | unsigned last = proc->rdq.last;
|
---|
[a2a4566] | 593 | if(last != MAX) {
|
---|
[e84ab3d] | 594 | struct thread$ * t = try_pop(cltr, last __STATS(, __tls_stats()->ready.pop.steal));
|
---|
[953827a] | 595 | if(t) return t;
|
---|
[a2a4566] | 596 | proc->rdq.last = MAX;
|
---|
[953827a] | 597 | }
|
---|
[12daa43] | 598 |
|
---|
| 599 | unsigned i = __tls_rand() % lanes.count;
|
---|
| 600 | return try_pop(cltr, i __STATS(, __tls_stats()->ready.pop.steal));
|
---|
| 601 | }
|
---|
[e84ab3d] | 602 | __attribute__((hot)) struct thread$ * pop_search(struct cluster * cltr) {
|
---|
[12daa43] | 603 | return search(cltr);
|
---|
| 604 | }
|
---|
| 605 | #endif
|
---|
[431cd4f] | 606 | #if defined(USE_RELAXED_FIFO)
|
---|
| 607 | //-----------------------------------------------------------------------
|
---|
| 608 | // get index from random number with or without bias towards queues
|
---|
| 609 | static inline [unsigned, bool] idx_from_r(unsigned r, unsigned preferred) {
|
---|
| 610 | unsigned i;
|
---|
| 611 | bool local;
|
---|
| 612 | unsigned rlow = r % BIAS;
|
---|
| 613 | unsigned rhigh = r / BIAS;
|
---|
| 614 | if((0 != rlow) && preferred >= 0) {
|
---|
| 615 | // (BIAS - 1) out of BIAS chances
|
---|
| 616 | // Use perferred queues
|
---|
| 617 | i = preferred + (rhigh % READYQ_SHARD_FACTOR);
|
---|
| 618 | local = true;
|
---|
| 619 | }
|
---|
| 620 | else {
|
---|
| 621 | // 1 out of BIAS chances
|
---|
| 622 | // Use all queues
|
---|
| 623 | i = rhigh;
|
---|
| 624 | local = false;
|
---|
| 625 | }
|
---|
| 626 | return [i, local];
|
---|
| 627 | }
|
---|
| 628 |
|
---|
[24e321c] | 629 | __attribute__((hot)) void push(struct cluster * cltr, struct thread$ * thrd, unpark_hint hint) with (cltr->ready_queue) {
|
---|
[431cd4f] | 630 | __cfadbg_print_safe(ready_queue, "Kernel : Pushing %p on cluster %p\n", thrd, cltr);
|
---|
[1b143de] | 631 |
|
---|
[24e321c] | 632 | const bool external = (hint != UNPARK_LOCAL) || (!kernelTLS().this_processor) || (cltr != kernelTLS().this_processor->cltr);
|
---|
[431cd4f] | 633 | /* paranoid */ verify(external || kernelTLS().this_processor->rdq.id < lanes.count );
|
---|
[fd1f65e] | 634 |
|
---|
[431cd4f] | 635 | bool local;
|
---|
| 636 | int preferred = external ? -1 : kernelTLS().this_processor->rdq.id;
|
---|
[52769ba] | 637 |
|
---|
[431cd4f] | 638 | // Try to pick a lane and lock it
|
---|
| 639 | unsigned i;
|
---|
| 640 | do {
|
---|
| 641 | // Pick the index of a lane
|
---|
| 642 | unsigned r = __tls_rand_fwd();
|
---|
| 643 | [i, local] = idx_from_r(r, preferred);
|
---|
[772411a] | 644 |
|
---|
[431cd4f] | 645 | i %= __atomic_load_n( &lanes.count, __ATOMIC_RELAXED );
|
---|
| 646 |
|
---|
| 647 | #if !defined(__CFA_NO_STATISTICS__)
|
---|
[d2fadeb] | 648 | if(unlikely(external)) __atomic_fetch_add(&cltr->stats->ready.push.extrn.attempt, 1, __ATOMIC_RELAXED);
|
---|
| 649 | else if(local) __tls_stats()->ready.push.local.attempt++;
|
---|
| 650 | else __tls_stats()->ready.push.share.attempt++;
|
---|
[431cd4f] | 651 | #endif
|
---|
[b798713] | 652 |
|
---|
[431cd4f] | 653 | // If we can't lock it retry
|
---|
| 654 | } while( !__atomic_try_acquire( &lanes.data[i].lock ) );
|
---|
| 655 |
|
---|
| 656 | // Actually push it
|
---|
| 657 | push(lanes.data[i], thrd);
|
---|
| 658 |
|
---|
[b808625] | 659 | // Unlock and return
|
---|
| 660 | __atomic_unlock( &lanes.data[i].lock );
|
---|
[431cd4f] | 661 |
|
---|
| 662 | // Mark the current index in the tls rng instance as having an item
|
---|
| 663 | __tls_rand_advance_bck();
|
---|
| 664 |
|
---|
| 665 | __cfadbg_print_safe(ready_queue, "Kernel : Pushed %p on cluster %p (idx: %u, mask %llu, first %d)\n", thrd, cltr, i, used.mask[0], lane_first);
|
---|
| 666 |
|
---|
| 667 | // Update statistics
|
---|
[b798713] | 668 | #if !defined(__CFA_NO_STATISTICS__)
|
---|
[d2fadeb] | 669 | if(unlikely(external)) __atomic_fetch_add(&cltr->stats->ready.push.extrn.success, 1, __ATOMIC_RELAXED);
|
---|
| 670 | else if(local) __tls_stats()->ready.push.local.success++;
|
---|
| 671 | else __tls_stats()->ready.push.share.success++;
|
---|
[b798713] | 672 | #endif
|
---|
[431cd4f] | 673 | }
|
---|
[b798713] | 674 |
|
---|
[431cd4f] | 675 | // Pop from the ready queue from a given cluster
|
---|
[e84ab3d] | 676 | __attribute__((hot)) thread$ * pop_fast(struct cluster * cltr) with (cltr->ready_queue) {
|
---|
[431cd4f] | 677 | /* paranoid */ verify( lanes.count > 0 );
|
---|
| 678 | /* paranoid */ verify( kernelTLS().this_processor );
|
---|
| 679 | /* paranoid */ verify( kernelTLS().this_processor->rdq.id < lanes.count );
|
---|
[b798713] | 680 |
|
---|
[431cd4f] | 681 | unsigned count = __atomic_load_n( &lanes.count, __ATOMIC_RELAXED );
|
---|
| 682 | int preferred = kernelTLS().this_processor->rdq.id;
|
---|
[dca5802] | 683 |
|
---|
| 684 |
|
---|
[431cd4f] | 685 | // As long as the list is not empty, try finding a lane that isn't empty and pop from it
|
---|
| 686 | for(25) {
|
---|
| 687 | // Pick two lists at random
|
---|
| 688 | unsigned ri = __tls_rand_bck();
|
---|
| 689 | unsigned rj = __tls_rand_bck();
|
---|
[c426b03] | 690 |
|
---|
[431cd4f] | 691 | unsigned i, j;
|
---|
| 692 | __attribute__((unused)) bool locali, localj;
|
---|
| 693 | [i, locali] = idx_from_r(ri, preferred);
|
---|
| 694 | [j, localj] = idx_from_r(rj, preferred);
|
---|
[1b143de] | 695 |
|
---|
[431cd4f] | 696 | i %= count;
|
---|
| 697 | j %= count;
|
---|
[9cc3a18] | 698 |
|
---|
[431cd4f] | 699 | // try popping from the 2 picked lists
|
---|
[e84ab3d] | 700 | struct thread$ * thrd = try_pop(cltr, i, j __STATS(, *(locali || localj ? &__tls_stats()->ready.pop.local : &__tls_stats()->ready.pop.help)));
|
---|
[431cd4f] | 701 | if(thrd) {
|
---|
| 702 | return thrd;
|
---|
| 703 | }
|
---|
| 704 | }
|
---|
[13c5e19] | 705 |
|
---|
[431cd4f] | 706 | // All lanes where empty return 0p
|
---|
| 707 | return 0p;
|
---|
| 708 | }
|
---|
[772411a] | 709 |
|
---|
[e84ab3d] | 710 | __attribute__((hot)) struct thread$ * pop_slow(struct cluster * cltr) { return pop_fast(cltr); }
|
---|
| 711 | __attribute__((hot)) struct thread$ * pop_search(struct cluster * cltr) {
|
---|
[431cd4f] | 712 | return search(cltr);
|
---|
| 713 | }
|
---|
| 714 | #endif
|
---|
| 715 | #if defined(USE_WORK_STEALING)
|
---|
[24e321c] | 716 | __attribute__((hot)) void push(struct cluster * cltr, struct thread$ * thrd, unpark_hint hint) with (cltr->ready_queue) {
|
---|
[431cd4f] | 717 | __cfadbg_print_safe(ready_queue, "Kernel : Pushing %p on cluster %p\n", thrd, cltr);
|
---|
[772411a] | 718 |
|
---|
[d3ba775] | 719 | // #define USE_PREFERRED
|
---|
| 720 | #if !defined(USE_PREFERRED)
|
---|
[24e321c] | 721 | const bool external = (hint != UNPARK_LOCAL) || (!kernelTLS().this_processor) || (cltr != kernelTLS().this_processor->cltr);
|
---|
[431cd4f] | 722 | /* paranoid */ verify(external || kernelTLS().this_processor->rdq.id < lanes.count );
|
---|
[d3ba775] | 723 | #else
|
---|
| 724 | unsigned preferred = thrd->preferred;
|
---|
[a2a4566] | 725 | const bool external = (hint != UNPARK_LOCAL) || (!kernelTLS().this_processor) || preferred == MAX || thrd->curr_cluster != cltr;
|
---|
[d3ba775] | 726 | /* paranoid */ verifyf(external || preferred < lanes.count, "Invalid preferred queue %u for %u lanes", preferred, lanes.count );
|
---|
[772411a] | 727 |
|
---|
[d3ba775] | 728 | unsigned r = preferred % READYQ_SHARD_FACTOR;
|
---|
| 729 | const unsigned start = preferred - r;
|
---|
[2b96031] | 730 | #endif
|
---|
[431cd4f] | 731 |
|
---|
| 732 | // Try to pick a lane and lock it
|
---|
| 733 | unsigned i;
|
---|
| 734 | do {
|
---|
[d2fadeb] | 735 | #if !defined(__CFA_NO_STATISTICS__)
|
---|
| 736 | if(unlikely(external)) __atomic_fetch_add(&cltr->stats->ready.push.extrn.attempt, 1, __ATOMIC_RELAXED);
|
---|
| 737 | else __tls_stats()->ready.push.local.attempt++;
|
---|
| 738 | #endif
|
---|
| 739 |
|
---|
[431cd4f] | 740 | if(unlikely(external)) {
|
---|
| 741 | i = __tls_rand() % lanes.count;
|
---|
| 742 | }
|
---|
| 743 | else {
|
---|
[d3ba775] | 744 | #if !defined(USE_PREFERRED)
|
---|
[b808625] | 745 | processor * proc = kernelTLS().this_processor;
|
---|
| 746 | unsigned r = proc->rdq.its++;
|
---|
| 747 | i = proc->rdq.id + (r % READYQ_SHARD_FACTOR);
|
---|
| 748 | #else
|
---|
[d3ba775] | 749 | i = start + (r++ % READYQ_SHARD_FACTOR);
|
---|
| 750 | #endif
|
---|
| 751 | }
|
---|
[431cd4f] | 752 | // If we can't lock it retry
|
---|
| 753 | } while( !__atomic_try_acquire( &lanes.data[i].lock ) );
|
---|
[13c5e19] | 754 |
|
---|
[431cd4f] | 755 | // Actually push it
|
---|
| 756 | push(lanes.data[i], thrd);
|
---|
[13c5e19] | 757 |
|
---|
[b808625] | 758 | // Unlock and return
|
---|
| 759 | __atomic_unlock( &lanes.data[i].lock );
|
---|
[431cd4f] | 760 |
|
---|
[d2fadeb] | 761 | #if !defined(__CFA_NO_STATISTICS__)
|
---|
| 762 | if(unlikely(external)) __atomic_fetch_add(&cltr->stats->ready.push.extrn.success, 1, __ATOMIC_RELAXED);
|
---|
| 763 | else __tls_stats()->ready.push.local.success++;
|
---|
| 764 | #endif
|
---|
| 765 |
|
---|
[431cd4f] | 766 | __cfadbg_print_safe(ready_queue, "Kernel : Pushed %p on cluster %p (idx: %u, mask %llu, first %d)\n", thrd, cltr, i, used.mask[0], lane_first);
|
---|
[13c5e19] | 767 | }
|
---|
| 768 |
|
---|
[431cd4f] | 769 | // Pop from the ready queue from a given cluster
|
---|
[e84ab3d] | 770 | __attribute__((hot)) thread$ * pop_fast(struct cluster * cltr) with (cltr->ready_queue) {
|
---|
[431cd4f] | 771 | /* paranoid */ verify( lanes.count > 0 );
|
---|
| 772 | /* paranoid */ verify( kernelTLS().this_processor );
|
---|
| 773 | /* paranoid */ verify( kernelTLS().this_processor->rdq.id < lanes.count );
|
---|
| 774 |
|
---|
| 775 | processor * proc = kernelTLS().this_processor;
|
---|
| 776 |
|
---|
[a2a4566] | 777 | if(proc->rdq.target == MAX) {
|
---|
[1680072] | 778 | unsigned long long min = ts(lanes.data[proc->rdq.id]);
|
---|
| 779 | for(int i = 0; i < READYQ_SHARD_FACTOR; i++) {
|
---|
| 780 | unsigned long long tsc = ts(lanes.data[proc->rdq.id + i]);
|
---|
| 781 | if(tsc < min) min = tsc;
|
---|
| 782 | }
|
---|
| 783 | proc->rdq.cutoff = min;
|
---|
[f55d54d] | 784 | proc->rdq.target = __tls_rand() % lanes.count;
|
---|
[431cd4f] | 785 | }
|
---|
[341aa39] | 786 | else {
|
---|
| 787 | unsigned target = proc->rdq.target;
|
---|
[a2a4566] | 788 | proc->rdq.target = MAX;
|
---|
[9cac0da] | 789 | const unsigned long long bias = 0; //2_500_000_000;
|
---|
| 790 | const unsigned long long cutoff = proc->rdq.cutoff > bias ? proc->rdq.cutoff - bias : proc->rdq.cutoff;
|
---|
| 791 | if(lanes.tscs[target].tv < cutoff && ts(lanes.data[target]) < cutoff) {
|
---|
[e84ab3d] | 792 | thread$ * t = try_pop(cltr, target __STATS(, __tls_stats()->ready.pop.help));
|
---|
[341aa39] | 793 | if(t) return t;
|
---|
| 794 | }
|
---|
[431cd4f] | 795 | }
|
---|
[13c5e19] | 796 |
|
---|
[431cd4f] | 797 | for(READYQ_SHARD_FACTOR) {
|
---|
[f55d54d] | 798 | unsigned i = proc->rdq.id + (proc->rdq.itr++ % READYQ_SHARD_FACTOR);
|
---|
[e84ab3d] | 799 | if(thread$ * t = try_pop(cltr, i __STATS(, __tls_stats()->ready.pop.local))) return t;
|
---|
[431cd4f] | 800 | }
|
---|
| 801 | return 0p;
|
---|
[1eb239e4] | 802 | }
|
---|
| 803 |
|
---|
[e84ab3d] | 804 | __attribute__((hot)) struct thread$ * pop_slow(struct cluster * cltr) with (cltr->ready_queue) {
|
---|
[fc59df78] | 805 | unsigned i = __tls_rand() % lanes.count;
|
---|
| 806 | return try_pop(cltr, i __STATS(, __tls_stats()->ready.pop.steal));
|
---|
| 807 | }
|
---|
[431cd4f] | 808 |
|
---|
[e84ab3d] | 809 | __attribute__((hot)) struct thread$ * pop_search(struct cluster * cltr) with (cltr->ready_queue) {
|
---|
[431cd4f] | 810 | return search(cltr);
|
---|
| 811 | }
|
---|
| 812 | #endif
|
---|
[1eb239e4] | 813 |
|
---|
[9cc3a18] | 814 | //=======================================================================
|
---|
| 815 | // Various Ready Queue utilities
|
---|
| 816 | //=======================================================================
|
---|
| 817 | // these function work the same or almost the same
|
---|
| 818 | // whether they are using work-stealing or relaxed fifo scheduling
|
---|
[1eb239e4] | 819 |
|
---|
[9cc3a18] | 820 | //-----------------------------------------------------------------------
|
---|
| 821 | // try to pop from a lane given by index w
|
---|
[e84ab3d] | 822 | static inline struct thread$ * try_pop(struct cluster * cltr, unsigned w __STATS(, __stats_readyQ_pop_t & stats)) with (cltr->ready_queue) {
|
---|
[a2a4566] | 823 | /* paranoid */ verify( w < lanes.count );
|
---|
[d2fadeb] | 824 | __STATS( stats.attempt++; )
|
---|
| 825 |
|
---|
[dca5802] | 826 | // Get relevant elements locally
|
---|
| 827 | __intrusive_lane_t & lane = lanes.data[w];
|
---|
| 828 |
|
---|
[b798713] | 829 | // If list looks empty retry
|
---|
[d2fadeb] | 830 | if( is_empty(lane) ) {
|
---|
| 831 | return 0p;
|
---|
| 832 | }
|
---|
[b798713] | 833 |
|
---|
| 834 | // If we can't get the lock retry
|
---|
[d2fadeb] | 835 | if( !__atomic_try_acquire(&lane.lock) ) {
|
---|
| 836 | return 0p;
|
---|
| 837 | }
|
---|
[b798713] | 838 |
|
---|
| 839 | // If list is empty, unlock and retry
|
---|
[dca5802] | 840 | if( is_empty(lane) ) {
|
---|
| 841 | __atomic_unlock(&lane.lock);
|
---|
[b798713] | 842 | return 0p;
|
---|
| 843 | }
|
---|
| 844 |
|
---|
| 845 | // Actually pop the list
|
---|
[e84ab3d] | 846 | struct thread$ * thrd;
|
---|
[a2a4566] | 847 | #if defined(USE_AWARE_STEALING) || defined(USE_WORK_STEALING) || defined(USE_CPU_WORK_STEALING)
|
---|
[078fb05] | 848 | unsigned long long tsc_before = ts(lane);
|
---|
| 849 | #endif
|
---|
[f302d80] | 850 | unsigned long long tsv;
|
---|
| 851 | [thrd, tsv] = pop(lane);
|
---|
[b798713] | 852 |
|
---|
[dca5802] | 853 | /* paranoid */ verify(thrd);
|
---|
[78ea291] | 854 | /* paranoid */ verify(tsv);
|
---|
[dca5802] | 855 | /* paranoid */ verify(lane.lock);
|
---|
[b798713] | 856 |
|
---|
| 857 | // Unlock and return
|
---|
[dca5802] | 858 | __atomic_unlock(&lane.lock);
|
---|
[b798713] | 859 |
|
---|
[dca5802] | 860 | // Update statistics
|
---|
[d2fadeb] | 861 | __STATS( stats.success++; )
|
---|
[b798713] | 862 |
|
---|
[a2a4566] | 863 | #if defined(USE_AWARE_STEALING) || defined(USE_WORK_STEALING) || defined(USE_CPU_WORK_STEALING)
|
---|
| 864 | if (tsv != MAX) {
|
---|
| 865 | unsigned long long now = rdtscl();
|
---|
| 866 | unsigned long long pma = __atomic_load_n(&lanes.tscs[w].ma, __ATOMIC_RELAXED);
|
---|
| 867 | __atomic_store_n(&lanes.tscs[w].tv, tsv, __ATOMIC_RELAXED);
|
---|
| 868 | __atomic_store_n(&lanes.tscs[w].ma, moving_average(now, tsc_before, pma), __ATOMIC_RELAXED);
|
---|
| 869 | }
|
---|
[9cc3a18] | 870 | #endif
|
---|
[d72c074] | 871 |
|
---|
[a2a4566] | 872 | #if defined(USE_AWARE_STEALING) || defined(USE_CPU_WORK_STEALING)
|
---|
[24e321c] | 873 | thrd->preferred = w / READYQ_SHARD_FACTOR;
|
---|
| 874 | #else
|
---|
| 875 | thrd->preferred = w;
|
---|
| 876 | #endif
|
---|
[d3ba775] | 877 |
|
---|
[dca5802] | 878 | // return the popped thread
|
---|
[b798713] | 879 | return thrd;
|
---|
| 880 | }
|
---|
[04b5cef] | 881 |
|
---|
[9cc3a18] | 882 | //-----------------------------------------------------------------------
|
---|
| 883 | // try to pop from any lanes making sure you don't miss any threads push
|
---|
| 884 | // before the start of the function
|
---|
[e84ab3d] | 885 | static inline struct thread$ * search(struct cluster * cltr) with (cltr->ready_queue) {
|
---|
[9cc3a18] | 886 | /* paranoid */ verify( lanes.count > 0 );
|
---|
| 887 | unsigned count = __atomic_load_n( &lanes.count, __ATOMIC_RELAXED );
|
---|
| 888 | unsigned offset = __tls_rand();
|
---|
| 889 | for(i; count) {
|
---|
| 890 | unsigned idx = (offset + i) % count;
|
---|
[e84ab3d] | 891 | struct thread$ * thrd = try_pop(cltr, idx __STATS(, __tls_stats()->ready.pop.search));
|
---|
[9cc3a18] | 892 | if(thrd) {
|
---|
| 893 | return thrd;
|
---|
| 894 | }
|
---|
[13c5e19] | 895 | }
|
---|
[9cc3a18] | 896 |
|
---|
| 897 | // All lanes where empty return 0p
|
---|
| 898 | return 0p;
|
---|
[b798713] | 899 | }
|
---|
| 900 |
|
---|
[24e321c] | 901 | //-----------------------------------------------------------------------
|
---|
| 902 | // get preferred ready for new thread
|
---|
| 903 | unsigned ready_queue_new_preferred() {
|
---|
| 904 | unsigned pref = 0;
|
---|
| 905 | if(struct thread$ * thrd = publicTLS_get( this_thread )) {
|
---|
| 906 | pref = thrd->preferred;
|
---|
| 907 | }
|
---|
| 908 | else {
|
---|
| 909 | #if defined(USE_CPU_WORK_STEALING)
|
---|
| 910 | pref = __kernel_getcpu();
|
---|
| 911 | #endif
|
---|
| 912 | }
|
---|
| 913 |
|
---|
| 914 | #if defined(USE_CPU_WORK_STEALING)
|
---|
| 915 | /* paranoid */ verify(pref >= 0);
|
---|
| 916 | /* paranoid */ verify(pref < cpu_info.hthrd_count);
|
---|
| 917 | #endif
|
---|
| 918 |
|
---|
| 919 | return pref;
|
---|
| 920 | }
|
---|
| 921 |
|
---|
[b798713] | 922 | //-----------------------------------------------------------------------
|
---|
[9cc3a18] | 923 | // Check that all the intrusive queues in the data structure are still consistent
|
---|
[b798713] | 924 | static void check( __ready_queue_t & q ) with (q) {
|
---|
[d3ba775] | 925 | #if defined(__CFA_WITH_VERIFY__)
|
---|
[b798713] | 926 | {
|
---|
[dca5802] | 927 | for( idx ; lanes.count ) {
|
---|
| 928 | __intrusive_lane_t & sl = lanes.data[idx];
|
---|
| 929 | assert(!lanes.data[idx].lock);
|
---|
[b798713] | 930 |
|
---|
[2b96031] | 931 | if(is_empty(sl)) {
|
---|
| 932 | assert( sl.anchor.next == 0p );
|
---|
[ef94ae7] | 933 | assert( sl.anchor.ts == -1llu );
|
---|
[2b96031] | 934 | assert( mock_head(sl) == sl.prev );
|
---|
| 935 | } else {
|
---|
| 936 | assert( sl.anchor.next != 0p );
|
---|
[ef94ae7] | 937 | assert( sl.anchor.ts != -1llu );
|
---|
[2b96031] | 938 | assert( mock_head(sl) != sl.prev );
|
---|
| 939 | }
|
---|
[b798713] | 940 | }
|
---|
| 941 | }
|
---|
| 942 | #endif
|
---|
| 943 | }
|
---|
| 944 |
|
---|
[9cc3a18] | 945 | //-----------------------------------------------------------------------
|
---|
| 946 | // Given 2 indexes, pick the list with the oldest push an try to pop from it
|
---|
[e84ab3d] | 947 | static inline struct thread$ * try_pop(struct cluster * cltr, unsigned i, unsigned j __STATS(, __stats_readyQ_pop_t & stats)) with (cltr->ready_queue) {
|
---|
[9cc3a18] | 948 | // Pick the bet list
|
---|
| 949 | int w = i;
|
---|
| 950 | if( __builtin_expect(!is_empty(lanes.data[j]), true) ) {
|
---|
| 951 | w = (ts(lanes.data[i]) < ts(lanes.data[j])) ? i : j;
|
---|
| 952 | }
|
---|
| 953 |
|
---|
[d2fadeb] | 954 | return try_pop(cltr, w __STATS(, stats));
|
---|
[9cc3a18] | 955 | }
|
---|
| 956 |
|
---|
[b798713] | 957 | // Call this function of the intrusive list was moved using memcpy
|
---|
[dca5802] | 958 | // fixes the list so that the pointers back to anchors aren't left dangling
|
---|
| 959 | static inline void fix(__intrusive_lane_t & ll) {
|
---|
[2b96031] | 960 | if(is_empty(ll)) {
|
---|
| 961 | verify(ll.anchor.next == 0p);
|
---|
| 962 | ll.prev = mock_head(ll);
|
---|
| 963 | }
|
---|
[b798713] | 964 | }
|
---|
| 965 |
|
---|
[69914cbc] | 966 | static void assign_list(unsigned & value, dlist(processor) & list, unsigned count) {
|
---|
[a017ee7] | 967 | processor * it = &list`first;
|
---|
| 968 | for(unsigned i = 0; i < count; i++) {
|
---|
| 969 | /* paranoid */ verifyf( it, "Unexpected null iterator, at index %u of %u\n", i, count);
|
---|
[431cd4f] | 970 | it->rdq.id = value;
|
---|
[a2a4566] | 971 | it->rdq.target = MAX;
|
---|
[9cc3a18] | 972 | value += READYQ_SHARD_FACTOR;
|
---|
[a017ee7] | 973 | it = &(*it)`next;
|
---|
| 974 | }
|
---|
| 975 | }
|
---|
| 976 |
|
---|
[9cc3a18] | 977 | static void reassign_cltr_id(struct cluster * cltr) {
|
---|
[a017ee7] | 978 | unsigned preferred = 0;
|
---|
[9cc3a18] | 979 | assign_list(preferred, cltr->procs.actives, cltr->procs.total - cltr->procs.idle);
|
---|
| 980 | assign_list(preferred, cltr->procs.idles , cltr->procs.idle );
|
---|
[a017ee7] | 981 | }
|
---|
| 982 |
|
---|
[431cd4f] | 983 | static void fix_times( struct cluster * cltr ) with( cltr->ready_queue ) {
|
---|
[a2a4566] | 984 | #if defined(USE_AWARE_STEALING) || defined(USE_WORK_STEALING)
|
---|
[431cd4f] | 985 | lanes.tscs = alloc(lanes.count, lanes.tscs`realloc);
|
---|
| 986 | for(i; lanes.count) {
|
---|
[a2a4566] | 987 | lanes.tscs[i].tv = rdtscl();
|
---|
| 988 | lanes.tscs[i].ma = 0;
|
---|
[431cd4f] | 989 | }
|
---|
| 990 | #endif
|
---|
| 991 | }
|
---|
| 992 |
|
---|
[12daa43] | 993 | #if defined(USE_CPU_WORK_STEALING)
|
---|
| 994 | // ready_queue size is fixed in this case
|
---|
| 995 | void ready_queue_grow(struct cluster * cltr) {}
|
---|
| 996 | void ready_queue_shrink(struct cluster * cltr) {}
|
---|
| 997 | #else
|
---|
| 998 | // Grow the ready queue
|
---|
| 999 | void ready_queue_grow(struct cluster * cltr) {
|
---|
| 1000 | size_t ncount;
|
---|
| 1001 | int target = cltr->procs.total;
|
---|
| 1002 |
|
---|
| 1003 | /* paranoid */ verify( ready_mutate_islocked() );
|
---|
| 1004 | __cfadbg_print_safe(ready_queue, "Kernel : Growing ready queue\n");
|
---|
| 1005 |
|
---|
| 1006 | // Make sure that everything is consistent
|
---|
| 1007 | /* paranoid */ check( cltr->ready_queue );
|
---|
| 1008 |
|
---|
| 1009 | // grow the ready queue
|
---|
| 1010 | with( cltr->ready_queue ) {
|
---|
| 1011 | // Find new count
|
---|
| 1012 | // Make sure we always have atleast 1 list
|
---|
| 1013 | if(target >= 2) {
|
---|
| 1014 | ncount = target * READYQ_SHARD_FACTOR;
|
---|
| 1015 | } else {
|
---|
| 1016 | ncount = SEQUENTIAL_SHARD;
|
---|
| 1017 | }
|
---|
[b798713] | 1018 |
|
---|
[12daa43] | 1019 | // Allocate new array (uses realloc and memcpies the data)
|
---|
| 1020 | lanes.data = alloc( ncount, lanes.data`realloc );
|
---|
[b798713] | 1021 |
|
---|
[12daa43] | 1022 | // Fix the moved data
|
---|
| 1023 | for( idx; (size_t)lanes.count ) {
|
---|
| 1024 | fix(lanes.data[idx]);
|
---|
| 1025 | }
|
---|
[b798713] | 1026 |
|
---|
[12daa43] | 1027 | // Construct new data
|
---|
| 1028 | for( idx; (size_t)lanes.count ~ ncount) {
|
---|
| 1029 | (lanes.data[idx]){};
|
---|
| 1030 | }
|
---|
[b798713] | 1031 |
|
---|
[12daa43] | 1032 | // Update original
|
---|
| 1033 | lanes.count = ncount;
|
---|
[a2a4566] | 1034 |
|
---|
| 1035 | lanes.caches = alloc( target, lanes.caches`realloc );
|
---|
[12daa43] | 1036 | }
|
---|
[b798713] | 1037 |
|
---|
[12daa43] | 1038 | fix_times(cltr);
|
---|
[9cc3a18] | 1039 |
|
---|
[12daa43] | 1040 | reassign_cltr_id(cltr);
|
---|
[a017ee7] | 1041 |
|
---|
[12daa43] | 1042 | // Make sure that everything is consistent
|
---|
| 1043 | /* paranoid */ check( cltr->ready_queue );
|
---|
[dca5802] | 1044 |
|
---|
[12daa43] | 1045 | __cfadbg_print_safe(ready_queue, "Kernel : Growing ready queue done\n");
|
---|
[dca5802] | 1046 |
|
---|
[12daa43] | 1047 | /* paranoid */ verify( ready_mutate_islocked() );
|
---|
| 1048 | }
|
---|
[b798713] | 1049 |
|
---|
[12daa43] | 1050 | // Shrink the ready queue
|
---|
| 1051 | void ready_queue_shrink(struct cluster * cltr) {
|
---|
| 1052 | /* paranoid */ verify( ready_mutate_islocked() );
|
---|
| 1053 | __cfadbg_print_safe(ready_queue, "Kernel : Shrinking ready queue\n");
|
---|
[dca5802] | 1054 |
|
---|
[12daa43] | 1055 | // Make sure that everything is consistent
|
---|
| 1056 | /* paranoid */ check( cltr->ready_queue );
|
---|
[dca5802] | 1057 |
|
---|
[12daa43] | 1058 | int target = cltr->procs.total;
|
---|
[a017ee7] | 1059 |
|
---|
[12daa43] | 1060 | with( cltr->ready_queue ) {
|
---|
| 1061 | // Remember old count
|
---|
| 1062 | size_t ocount = lanes.count;
|
---|
[b798713] | 1063 |
|
---|
[12daa43] | 1064 | // Find new count
|
---|
| 1065 | // Make sure we always have atleast 1 list
|
---|
| 1066 | lanes.count = target >= 2 ? target * READYQ_SHARD_FACTOR: SEQUENTIAL_SHARD;
|
---|
| 1067 | /* paranoid */ verify( ocount >= lanes.count );
|
---|
| 1068 | /* paranoid */ verify( lanes.count == target * READYQ_SHARD_FACTOR || target < 2 );
|
---|
[dca5802] | 1069 |
|
---|
[12daa43] | 1070 | // for printing count the number of displaced threads
|
---|
| 1071 | #if defined(__CFA_DEBUG_PRINT__) || defined(__CFA_DEBUG_PRINT_READY_QUEUE__)
|
---|
| 1072 | __attribute__((unused)) size_t displaced = 0;
|
---|
| 1073 | #endif
|
---|
[b798713] | 1074 |
|
---|
[12daa43] | 1075 | // redistribute old data
|
---|
| 1076 | for( idx; (size_t)lanes.count ~ ocount) {
|
---|
| 1077 | // Lock is not strictly needed but makes checking invariants much easier
|
---|
| 1078 | __attribute__((unused)) bool locked = __atomic_try_acquire(&lanes.data[idx].lock);
|
---|
| 1079 | verify(locked);
|
---|
[dca5802] | 1080 |
|
---|
[12daa43] | 1081 | // As long as we can pop from this lane to push the threads somewhere else in the queue
|
---|
| 1082 | while(!is_empty(lanes.data[idx])) {
|
---|
[e84ab3d] | 1083 | struct thread$ * thrd;
|
---|
[12daa43] | 1084 | unsigned long long _;
|
---|
| 1085 | [thrd, _] = pop(lanes.data[idx]);
|
---|
[dca5802] | 1086 |
|
---|
[12daa43] | 1087 | push(cltr, thrd, true);
|
---|
[dca5802] | 1088 |
|
---|
[12daa43] | 1089 | // for printing count the number of displaced threads
|
---|
| 1090 | #if defined(__CFA_DEBUG_PRINT__) || defined(__CFA_DEBUG_PRINT_READY_QUEUE__)
|
---|
| 1091 | displaced++;
|
---|
| 1092 | #endif
|
---|
| 1093 | }
|
---|
[b798713] | 1094 |
|
---|
[12daa43] | 1095 | // Unlock the lane
|
---|
| 1096 | __atomic_unlock(&lanes.data[idx].lock);
|
---|
[b798713] | 1097 |
|
---|
[12daa43] | 1098 | // TODO print the queue statistics here
|
---|
[b798713] | 1099 |
|
---|
[12daa43] | 1100 | ^(lanes.data[idx]){};
|
---|
| 1101 | }
|
---|
[b798713] | 1102 |
|
---|
[12daa43] | 1103 | __cfadbg_print_safe(ready_queue, "Kernel : Shrinking ready queue displaced %zu threads\n", displaced);
|
---|
[c84b4be] | 1104 |
|
---|
[12daa43] | 1105 | // Allocate new array (uses realloc and memcpies the data)
|
---|
| 1106 | lanes.data = alloc( lanes.count, lanes.data`realloc );
|
---|
[b798713] | 1107 |
|
---|
[12daa43] | 1108 | // Fix the moved data
|
---|
| 1109 | for( idx; (size_t)lanes.count ) {
|
---|
| 1110 | fix(lanes.data[idx]);
|
---|
| 1111 | }
|
---|
[a2a4566] | 1112 |
|
---|
| 1113 | lanes.caches = alloc( target, lanes.caches`realloc );
|
---|
[b798713] | 1114 | }
|
---|
| 1115 |
|
---|
[12daa43] | 1116 | fix_times(cltr);
|
---|
[9cc3a18] | 1117 |
|
---|
[a2a4566] | 1118 |
|
---|
[12daa43] | 1119 | reassign_cltr_id(cltr);
|
---|
[a017ee7] | 1120 |
|
---|
[12daa43] | 1121 | // Make sure that everything is consistent
|
---|
| 1122 | /* paranoid */ check( cltr->ready_queue );
|
---|
[dca5802] | 1123 |
|
---|
[12daa43] | 1124 | __cfadbg_print_safe(ready_queue, "Kernel : Shrinking ready queue done\n");
|
---|
| 1125 | /* paranoid */ verify( ready_mutate_islocked() );
|
---|
| 1126 | }
|
---|
| 1127 | #endif
|
---|
[8cd5434] | 1128 |
|
---|
| 1129 | #if !defined(__CFA_NO_STATISTICS__)
|
---|
| 1130 | unsigned cnt(const __ready_queue_t & this, unsigned idx) {
|
---|
| 1131 | /* paranoid */ verify(this.lanes.count > idx);
|
---|
| 1132 | return this.lanes.data[idx].cnt;
|
---|
| 1133 | }
|
---|
| 1134 | #endif
|
---|
[0ee224b] | 1135 |
|
---|
| 1136 |
|
---|
| 1137 | #if defined(CFA_HAVE_LINUX_LIBRSEQ)
|
---|
| 1138 | // No definition needed
|
---|
| 1139 | #elif defined(CFA_HAVE_LINUX_RSEQ_H)
|
---|
| 1140 |
|
---|
| 1141 | #if defined( __x86_64 ) || defined( __i386 )
|
---|
| 1142 | #define RSEQ_SIG 0x53053053
|
---|
| 1143 | #elif defined( __ARM_ARCH )
|
---|
| 1144 | #ifdef __ARMEB__
|
---|
| 1145 | #define RSEQ_SIG 0xf3def5e7 /* udf #24035 ; 0x5de3 (ARMv6+) */
|
---|
| 1146 | #else
|
---|
| 1147 | #define RSEQ_SIG 0xe7f5def3 /* udf #24035 ; 0x5de3 */
|
---|
| 1148 | #endif
|
---|
| 1149 | #endif
|
---|
| 1150 |
|
---|
| 1151 | extern void __disable_interrupts_hard();
|
---|
| 1152 | extern void __enable_interrupts_hard();
|
---|
| 1153 |
|
---|
[75c7252] | 1154 | static void __kernel_raw_rseq_register (void) {
|
---|
[0ee224b] | 1155 | /* paranoid */ verify( __cfaabi_rseq.cpu_id == RSEQ_CPU_ID_UNINITIALIZED );
|
---|
| 1156 |
|
---|
| 1157 | // int ret = syscall(__NR_rseq, &__cfaabi_rseq, sizeof(struct rseq), 0, (sigset_t *)0p, _NSIG / 8);
|
---|
| 1158 | int ret = syscall(__NR_rseq, &__cfaabi_rseq, sizeof(struct rseq), 0, RSEQ_SIG);
|
---|
| 1159 | if(ret != 0) {
|
---|
| 1160 | int e = errno;
|
---|
| 1161 | switch(e) {
|
---|
| 1162 | case EINVAL: abort("KERNEL ERROR: rseq register invalid argument");
|
---|
| 1163 | case ENOSYS: abort("KERNEL ERROR: rseq register no supported");
|
---|
| 1164 | case EFAULT: abort("KERNEL ERROR: rseq register with invalid argument");
|
---|
| 1165 | case EBUSY : abort("KERNEL ERROR: rseq register already registered");
|
---|
| 1166 | case EPERM : abort("KERNEL ERROR: rseq register sig argument on unregistration does not match the signature received on registration");
|
---|
| 1167 | default: abort("KERNEL ERROR: rseq register unexpected return %d", e);
|
---|
| 1168 | }
|
---|
| 1169 | }
|
---|
| 1170 | }
|
---|
| 1171 |
|
---|
[75c7252] | 1172 | static void __kernel_raw_rseq_unregister(void) {
|
---|
[0ee224b] | 1173 | /* paranoid */ verify( __cfaabi_rseq.cpu_id >= 0 );
|
---|
| 1174 |
|
---|
| 1175 | // int ret = syscall(__NR_rseq, &__cfaabi_rseq, sizeof(struct rseq), RSEQ_FLAG_UNREGISTER, (sigset_t *)0p, _NSIG / 8);
|
---|
| 1176 | int ret = syscall(__NR_rseq, &__cfaabi_rseq, sizeof(struct rseq), RSEQ_FLAG_UNREGISTER, RSEQ_SIG);
|
---|
| 1177 | if(ret != 0) {
|
---|
| 1178 | int e = errno;
|
---|
| 1179 | switch(e) {
|
---|
| 1180 | case EINVAL: abort("KERNEL ERROR: rseq unregister invalid argument");
|
---|
| 1181 | case ENOSYS: abort("KERNEL ERROR: rseq unregister no supported");
|
---|
| 1182 | case EFAULT: abort("KERNEL ERROR: rseq unregister with invalid argument");
|
---|
| 1183 | case EBUSY : abort("KERNEL ERROR: rseq unregister already registered");
|
---|
| 1184 | case EPERM : abort("KERNEL ERROR: rseq unregister sig argument on unregistration does not match the signature received on registration");
|
---|
| 1185 | default: abort("KERNEL ERROR: rseq unregisteunexpected return %d", e);
|
---|
| 1186 | }
|
---|
| 1187 | }
|
---|
| 1188 | }
|
---|
| 1189 | #else
|
---|
| 1190 | // No definition needed
|
---|
[a2a4566] | 1191 | #endif
|
---|