.. | .. |
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2 | 2 | /* |
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3 | 3 | * padata.c - generic interface to process data streams in parallel |
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4 | 4 | * |
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5 | | - * See Documentation/padata.txt for an api documentation. |
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| 5 | + * See Documentation/core-api/padata.rst for more information. |
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6 | 6 | * |
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7 | 7 | * Copyright (C) 2008, 2009 secunet Security Networks AG |
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8 | 8 | * Copyright (C) 2008, 2009 Steffen Klassert <steffen.klassert@secunet.com> |
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| 9 | + * |
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| 10 | + * Copyright (c) 2020 Oracle and/or its affiliates. |
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| 11 | + * Author: Daniel Jordan <daniel.m.jordan@oracle.com> |
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9 | 12 | * |
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10 | 13 | * This program is free software; you can redistribute it and/or modify it |
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11 | 14 | * under the terms and conditions of the GNU General Public License, |
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.. | .. |
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21 | 24 | * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. |
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22 | 25 | */ |
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23 | 26 | |
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| 27 | +#include <linux/completion.h> |
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24 | 28 | #include <linux/export.h> |
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25 | 29 | #include <linux/cpumask.h> |
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26 | 30 | #include <linux/err.h> |
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.. | .. |
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31 | 35 | #include <linux/slab.h> |
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32 | 36 | #include <linux/sysfs.h> |
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33 | 37 | #include <linux/rcupdate.h> |
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34 | | -#include <linux/module.h> |
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35 | 38 | |
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36 | | -#define MAX_OBJ_NUM 1000 |
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| 39 | +#define PADATA_WORK_ONSTACK 1 /* Work's memory is on stack */ |
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| 40 | + |
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| 41 | +struct padata_work { |
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| 42 | + struct work_struct pw_work; |
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| 43 | + struct list_head pw_list; /* padata_free_works linkage */ |
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| 44 | + void *pw_data; |
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| 45 | +}; |
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| 46 | + |
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| 47 | +static DEFINE_SPINLOCK(padata_works_lock); |
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| 48 | +static struct padata_work *padata_works; |
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| 49 | +static LIST_HEAD(padata_free_works); |
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| 50 | + |
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| 51 | +struct padata_mt_job_state { |
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| 52 | + spinlock_t lock; |
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| 53 | + struct completion completion; |
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| 54 | + struct padata_mt_job *job; |
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| 55 | + int nworks; |
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| 56 | + int nworks_fini; |
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| 57 | + unsigned long chunk_size; |
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| 58 | +}; |
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37 | 59 | |
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38 | 60 | static void padata_free_pd(struct parallel_data *pd); |
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| 61 | +static void __init padata_mt_helper(struct work_struct *work); |
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39 | 62 | |
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40 | 63 | static int padata_index_to_cpu(struct parallel_data *pd, int cpu_index) |
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41 | 64 | { |
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.. | .. |
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48 | 71 | return target_cpu; |
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49 | 72 | } |
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50 | 73 | |
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51 | | -static int padata_cpu_hash(struct parallel_data *pd) |
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| 74 | +static int padata_cpu_hash(struct parallel_data *pd, unsigned int seq_nr) |
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52 | 75 | { |
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53 | | - unsigned int seq_nr; |
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54 | | - int cpu_index; |
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55 | | - |
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56 | 76 | /* |
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57 | 77 | * Hash the sequence numbers to the cpus by taking |
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58 | 78 | * seq_nr mod. number of cpus in use. |
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59 | 79 | */ |
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60 | | - |
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61 | | - seq_nr = atomic_inc_return(&pd->seq_nr); |
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62 | | - cpu_index = seq_nr % cpumask_weight(pd->cpumask.pcpu); |
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| 80 | + int cpu_index = seq_nr % cpumask_weight(pd->cpumask.pcpu); |
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63 | 81 | |
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64 | 82 | return padata_index_to_cpu(pd, cpu_index); |
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65 | 83 | } |
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66 | 84 | |
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| 85 | +static struct padata_work *padata_work_alloc(void) |
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| 86 | +{ |
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| 87 | + struct padata_work *pw; |
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| 88 | + |
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| 89 | + lockdep_assert_held(&padata_works_lock); |
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| 90 | + |
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| 91 | + if (list_empty(&padata_free_works)) |
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| 92 | + return NULL; /* No more work items allowed to be queued. */ |
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| 93 | + |
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| 94 | + pw = list_first_entry(&padata_free_works, struct padata_work, pw_list); |
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| 95 | + list_del(&pw->pw_list); |
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| 96 | + return pw; |
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| 97 | +} |
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| 98 | + |
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| 99 | +static void padata_work_init(struct padata_work *pw, work_func_t work_fn, |
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| 100 | + void *data, int flags) |
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| 101 | +{ |
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| 102 | + if (flags & PADATA_WORK_ONSTACK) |
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| 103 | + INIT_WORK_ONSTACK(&pw->pw_work, work_fn); |
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| 104 | + else |
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| 105 | + INIT_WORK(&pw->pw_work, work_fn); |
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| 106 | + pw->pw_data = data; |
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| 107 | +} |
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| 108 | + |
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| 109 | +static int __init padata_work_alloc_mt(int nworks, void *data, |
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| 110 | + struct list_head *head) |
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| 111 | +{ |
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| 112 | + int i; |
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| 113 | + |
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| 114 | + spin_lock(&padata_works_lock); |
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| 115 | + /* Start at 1 because the current task participates in the job. */ |
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| 116 | + for (i = 1; i < nworks; ++i) { |
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| 117 | + struct padata_work *pw = padata_work_alloc(); |
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| 118 | + |
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| 119 | + if (!pw) |
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| 120 | + break; |
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| 121 | + padata_work_init(pw, padata_mt_helper, data, 0); |
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| 122 | + list_add(&pw->pw_list, head); |
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| 123 | + } |
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| 124 | + spin_unlock(&padata_works_lock); |
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| 125 | + |
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| 126 | + return i; |
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| 127 | +} |
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| 128 | + |
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| 129 | +static void padata_work_free(struct padata_work *pw) |
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| 130 | +{ |
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| 131 | + lockdep_assert_held(&padata_works_lock); |
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| 132 | + list_add(&pw->pw_list, &padata_free_works); |
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| 133 | +} |
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| 134 | + |
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| 135 | +static void __init padata_works_free(struct list_head *works) |
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| 136 | +{ |
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| 137 | + struct padata_work *cur, *next; |
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| 138 | + |
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| 139 | + if (list_empty(works)) |
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| 140 | + return; |
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| 141 | + |
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| 142 | + spin_lock(&padata_works_lock); |
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| 143 | + list_for_each_entry_safe(cur, next, works, pw_list) { |
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| 144 | + list_del(&cur->pw_list); |
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| 145 | + padata_work_free(cur); |
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| 146 | + } |
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| 147 | + spin_unlock(&padata_works_lock); |
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| 148 | +} |
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| 149 | + |
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67 | 150 | static void padata_parallel_worker(struct work_struct *parallel_work) |
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68 | 151 | { |
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69 | | - struct padata_parallel_queue *pqueue; |
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70 | | - LIST_HEAD(local_list); |
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| 152 | + struct padata_work *pw = container_of(parallel_work, struct padata_work, |
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| 153 | + pw_work); |
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| 154 | + struct padata_priv *padata = pw->pw_data; |
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71 | 155 | |
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72 | 156 | local_bh_disable(); |
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73 | | - pqueue = container_of(parallel_work, |
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74 | | - struct padata_parallel_queue, work); |
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75 | | - |
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76 | | - spin_lock(&pqueue->parallel.lock); |
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77 | | - list_replace_init(&pqueue->parallel.list, &local_list); |
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78 | | - spin_unlock(&pqueue->parallel.lock); |
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79 | | - |
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80 | | - while (!list_empty(&local_list)) { |
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81 | | - struct padata_priv *padata; |
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82 | | - |
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83 | | - padata = list_entry(local_list.next, |
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84 | | - struct padata_priv, list); |
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85 | | - |
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86 | | - list_del_init(&padata->list); |
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87 | | - |
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88 | | - padata->parallel(padata); |
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89 | | - } |
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90 | | - |
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| 157 | + padata->parallel(padata); |
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| 158 | + spin_lock(&padata_works_lock); |
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| 159 | + padata_work_free(pw); |
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| 160 | + spin_unlock(&padata_works_lock); |
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91 | 161 | local_bh_enable(); |
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92 | 162 | } |
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93 | 163 | |
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94 | 164 | /** |
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95 | 165 | * padata_do_parallel - padata parallelization function |
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96 | 166 | * |
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97 | | - * @pinst: padata instance |
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| 167 | + * @ps: padatashell |
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98 | 168 | * @padata: object to be parallelized |
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99 | | - * @cb_cpu: cpu the serialization callback function will run on, |
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100 | | - * must be in the serial cpumask of padata(i.e. cpumask.cbcpu). |
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| 169 | + * @cb_cpu: pointer to the CPU that the serialization callback function should |
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| 170 | + * run on. If it's not in the serial cpumask of @pinst |
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| 171 | + * (i.e. cpumask.cbcpu), this function selects a fallback CPU and if |
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| 172 | + * none found, returns -EINVAL. |
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101 | 173 | * |
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102 | 174 | * The parallelization callback function will run with BHs off. |
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103 | 175 | * Note: Every object which is parallelized by padata_do_parallel |
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104 | 176 | * must be seen by padata_do_serial. |
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| 177 | + * |
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| 178 | + * Return: 0 on success or else negative error code. |
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105 | 179 | */ |
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106 | | -int padata_do_parallel(struct padata_instance *pinst, |
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107 | | - struct padata_priv *padata, int cb_cpu) |
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| 180 | +int padata_do_parallel(struct padata_shell *ps, |
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| 181 | + struct padata_priv *padata, int *cb_cpu) |
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108 | 182 | { |
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109 | | - int target_cpu, err; |
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110 | | - struct padata_parallel_queue *queue; |
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| 183 | + struct padata_instance *pinst = ps->pinst; |
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| 184 | + int i, cpu, cpu_index, err; |
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111 | 185 | struct parallel_data *pd; |
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| 186 | + struct padata_work *pw; |
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112 | 187 | |
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113 | 188 | rcu_read_lock_bh(); |
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114 | 189 | |
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115 | | - pd = rcu_dereference_bh(pinst->pd); |
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| 190 | + pd = rcu_dereference_bh(ps->pd); |
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116 | 191 | |
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117 | 192 | err = -EINVAL; |
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118 | 193 | if (!(pinst->flags & PADATA_INIT) || pinst->flags & PADATA_INVALID) |
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119 | 194 | goto out; |
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120 | 195 | |
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121 | | - if (!cpumask_test_cpu(cb_cpu, pd->cpumask.cbcpu)) |
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122 | | - goto out; |
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| 196 | + if (!cpumask_test_cpu(*cb_cpu, pd->cpumask.cbcpu)) { |
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| 197 | + if (!cpumask_weight(pd->cpumask.cbcpu)) |
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| 198 | + goto out; |
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| 199 | + |
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| 200 | + /* Select an alternate fallback CPU and notify the caller. */ |
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| 201 | + cpu_index = *cb_cpu % cpumask_weight(pd->cpumask.cbcpu); |
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| 202 | + |
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| 203 | + cpu = cpumask_first(pd->cpumask.cbcpu); |
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| 204 | + for (i = 0; i < cpu_index; i++) |
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| 205 | + cpu = cpumask_next(cpu, pd->cpumask.cbcpu); |
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| 206 | + |
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| 207 | + *cb_cpu = cpu; |
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| 208 | + } |
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123 | 209 | |
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124 | 210 | err = -EBUSY; |
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125 | 211 | if ((pinst->flags & PADATA_RESET)) |
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126 | 212 | goto out; |
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127 | 213 | |
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128 | | - if (atomic_read(&pd->refcnt) >= MAX_OBJ_NUM) |
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129 | | - goto out; |
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130 | | - |
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131 | | - err = 0; |
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132 | 214 | atomic_inc(&pd->refcnt); |
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133 | 215 | padata->pd = pd; |
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134 | | - padata->cb_cpu = cb_cpu; |
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| 216 | + padata->cb_cpu = *cb_cpu; |
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135 | 217 | |
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136 | | - target_cpu = padata_cpu_hash(pd); |
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137 | | - padata->cpu = target_cpu; |
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138 | | - queue = per_cpu_ptr(pd->pqueue, target_cpu); |
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| 218 | + spin_lock(&padata_works_lock); |
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| 219 | + padata->seq_nr = ++pd->seq_nr; |
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| 220 | + pw = padata_work_alloc(); |
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| 221 | + spin_unlock(&padata_works_lock); |
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139 | 222 | |
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140 | | - spin_lock(&queue->parallel.lock); |
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141 | | - list_add_tail(&padata->list, &queue->parallel.list); |
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142 | | - spin_unlock(&queue->parallel.lock); |
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| 223 | + if (!pw) { |
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| 224 | + /* Maximum works limit exceeded, run in the current task. */ |
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| 225 | + padata->parallel(padata); |
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| 226 | + } |
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143 | 227 | |
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144 | | - queue_work_on(target_cpu, pinst->wq, &queue->work); |
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| 228 | + rcu_read_unlock_bh(); |
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145 | 229 | |
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| 230 | + if (pw) { |
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| 231 | + padata_work_init(pw, padata_parallel_worker, padata, 0); |
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| 232 | + queue_work(pinst->parallel_wq, &pw->pw_work); |
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| 233 | + } |
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| 234 | + |
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| 235 | + return 0; |
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146 | 236 | out: |
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147 | 237 | rcu_read_unlock_bh(); |
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148 | 238 | |
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.. | .. |
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151 | 241 | EXPORT_SYMBOL(padata_do_parallel); |
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152 | 242 | |
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153 | 243 | /* |
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154 | | - * padata_get_next - Get the next object that needs serialization. |
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| 244 | + * padata_find_next - Find the next object that needs serialization. |
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155 | 245 | * |
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156 | | - * Return values are: |
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157 | | - * |
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158 | | - * A pointer to the control struct of the next object that needs |
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159 | | - * serialization, if present in one of the percpu reorder queues. |
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160 | | - * |
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161 | | - * -EINPROGRESS, if the next object that needs serialization will |
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162 | | - * be parallel processed by another cpu and is not yet present in |
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163 | | - * the cpu's reorder queue. |
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164 | | - * |
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165 | | - * -ENODATA, if this cpu has to do the parallel processing for |
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166 | | - * the next object. |
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| 246 | + * Return: |
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| 247 | + * * A pointer to the control struct of the next object that needs |
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| 248 | + * serialization, if present in one of the percpu reorder queues. |
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| 249 | + * * NULL, if the next object that needs serialization will |
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| 250 | + * be parallel processed by another cpu and is not yet present in |
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| 251 | + * the cpu's reorder queue. |
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167 | 252 | */ |
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168 | | -static struct padata_priv *padata_get_next(struct parallel_data *pd) |
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| 253 | +static struct padata_priv *padata_find_next(struct parallel_data *pd, |
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| 254 | + bool remove_object) |
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169 | 255 | { |
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170 | | - struct padata_parallel_queue *next_queue; |
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171 | 256 | struct padata_priv *padata; |
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172 | 257 | struct padata_list *reorder; |
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173 | 258 | int cpu = pd->cpu; |
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174 | 259 | |
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175 | | - next_queue = per_cpu_ptr(pd->pqueue, cpu); |
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176 | | - reorder = &next_queue->reorder; |
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| 260 | + reorder = per_cpu_ptr(pd->reorder_list, cpu); |
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177 | 261 | |
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178 | 262 | spin_lock(&reorder->lock); |
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179 | | - if (!list_empty(&reorder->list)) { |
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180 | | - padata = list_entry(reorder->list.next, |
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181 | | - struct padata_priv, list); |
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182 | | - |
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183 | | - list_del_init(&padata->list); |
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184 | | - atomic_dec(&pd->reorder_objects); |
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185 | | - |
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186 | | - pd->cpu = cpumask_next_wrap(cpu, pd->cpumask.pcpu, -1, |
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187 | | - false); |
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188 | | - |
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| 263 | + if (list_empty(&reorder->list)) { |
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189 | 264 | spin_unlock(&reorder->lock); |
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190 | | - goto out; |
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| 265 | + return NULL; |
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191 | 266 | } |
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| 267 | + |
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| 268 | + padata = list_entry(reorder->list.next, struct padata_priv, list); |
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| 269 | + |
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| 270 | + /* |
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| 271 | + * Checks the rare case where two or more parallel jobs have hashed to |
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| 272 | + * the same CPU and one of the later ones finishes first. |
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| 273 | + */ |
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| 274 | + if (padata->seq_nr != pd->processed) { |
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| 275 | + spin_unlock(&reorder->lock); |
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| 276 | + return NULL; |
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| 277 | + } |
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| 278 | + |
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| 279 | + if (remove_object) { |
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| 280 | + list_del_init(&padata->list); |
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| 281 | + ++pd->processed; |
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| 282 | + pd->cpu = cpumask_next_wrap(cpu, pd->cpumask.pcpu, -1, false); |
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| 283 | + } |
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| 284 | + |
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192 | 285 | spin_unlock(&reorder->lock); |
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193 | | - |
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194 | | - if (__this_cpu_read(pd->pqueue->cpu_index) == next_queue->cpu_index) { |
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195 | | - padata = ERR_PTR(-ENODATA); |
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196 | | - goto out; |
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197 | | - } |
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198 | | - |
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199 | | - padata = ERR_PTR(-EINPROGRESS); |
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200 | | -out: |
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201 | 286 | return padata; |
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202 | 287 | } |
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203 | 288 | |
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204 | 289 | static void padata_reorder(struct parallel_data *pd) |
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205 | 290 | { |
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| 291 | + struct padata_instance *pinst = pd->ps->pinst; |
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206 | 292 | int cb_cpu; |
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207 | 293 | struct padata_priv *padata; |
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208 | 294 | struct padata_serial_queue *squeue; |
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209 | | - struct padata_instance *pinst = pd->pinst; |
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210 | | - struct padata_parallel_queue *next_queue; |
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| 295 | + struct padata_list *reorder; |
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211 | 296 | |
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212 | 297 | /* |
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213 | 298 | * We need to ensure that only one cpu can work on dequeueing of |
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.. | .. |
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223 | 308 | return; |
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224 | 309 | |
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225 | 310 | while (1) { |
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226 | | - padata = padata_get_next(pd); |
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| 311 | + padata = padata_find_next(pd, true); |
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227 | 312 | |
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228 | 313 | /* |
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229 | 314 | * If the next object that needs serialization is parallel |
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230 | 315 | * processed by another cpu and is still on it's way to the |
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231 | 316 | * cpu's reorder queue, nothing to do for now. |
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232 | 317 | */ |
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233 | | - if (PTR_ERR(padata) == -EINPROGRESS) |
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| 318 | + if (!padata) |
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234 | 319 | break; |
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235 | | - |
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236 | | - /* |
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237 | | - * This cpu has to do the parallel processing of the next |
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238 | | - * object. It's waiting in the cpu's parallelization queue, |
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239 | | - * so exit immediately. |
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240 | | - */ |
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241 | | - if (PTR_ERR(padata) == -ENODATA) { |
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242 | | - spin_unlock_bh(&pd->lock); |
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243 | | - return; |
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244 | | - } |
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245 | 320 | |
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246 | 321 | cb_cpu = padata->cb_cpu; |
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247 | 322 | squeue = per_cpu_ptr(pd->squeue, cb_cpu); |
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.. | .. |
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250 | 325 | list_add_tail(&padata->list, &squeue->serial.list); |
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251 | 326 | spin_unlock(&squeue->serial.lock); |
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252 | 327 | |
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253 | | - queue_work_on(cb_cpu, pinst->wq, &squeue->work); |
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| 328 | + queue_work_on(cb_cpu, pinst->serial_wq, &squeue->work); |
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254 | 329 | } |
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255 | 330 | |
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256 | 331 | spin_unlock_bh(&pd->lock); |
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.. | .. |
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261 | 336 | * |
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262 | 337 | * Ensure reorder queue is read after pd->lock is dropped so we see |
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263 | 338 | * new objects from another task in padata_do_serial. Pairs with |
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264 | | - * smp_mb__after_atomic in padata_do_serial. |
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| 339 | + * smp_mb in padata_do_serial. |
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265 | 340 | */ |
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266 | 341 | smp_mb(); |
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267 | 342 | |
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268 | | - next_queue = per_cpu_ptr(pd->pqueue, pd->cpu); |
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269 | | - if (!list_empty(&next_queue->reorder.list)) |
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270 | | - queue_work(pinst->wq, &pd->reorder_work); |
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| 343 | + reorder = per_cpu_ptr(pd->reorder_list, pd->cpu); |
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| 344 | + if (!list_empty(&reorder->list) && padata_find_next(pd, false)) |
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| 345 | + queue_work(pinst->serial_wq, &pd->reorder_work); |
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271 | 346 | } |
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272 | 347 | |
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273 | 348 | static void invoke_padata_reorder(struct work_struct *work) |
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.. | .. |
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325 | 400 | void padata_do_serial(struct padata_priv *padata) |
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326 | 401 | { |
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327 | 402 | struct parallel_data *pd = padata->pd; |
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328 | | - struct padata_parallel_queue *pqueue = per_cpu_ptr(pd->pqueue, |
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329 | | - padata->cpu); |
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| 403 | + int hashed_cpu = padata_cpu_hash(pd, padata->seq_nr); |
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| 404 | + struct padata_list *reorder = per_cpu_ptr(pd->reorder_list, hashed_cpu); |
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| 405 | + struct padata_priv *cur; |
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| 406 | + struct list_head *pos; |
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330 | 407 | |
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331 | | - spin_lock(&pqueue->reorder.lock); |
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332 | | - list_add_tail(&padata->list, &pqueue->reorder.list); |
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333 | | - atomic_inc(&pd->reorder_objects); |
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334 | | - spin_unlock(&pqueue->reorder.lock); |
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| 408 | + spin_lock(&reorder->lock); |
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| 409 | + /* Sort in ascending order of sequence number. */ |
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| 410 | + list_for_each_prev(pos, &reorder->list) { |
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| 411 | + cur = list_entry(pos, struct padata_priv, list); |
---|
| 412 | + if (cur->seq_nr < padata->seq_nr) |
---|
| 413 | + break; |
---|
| 414 | + } |
---|
| 415 | + list_add(&padata->list, pos); |
---|
| 416 | + spin_unlock(&reorder->lock); |
---|
335 | 417 | |
---|
336 | 418 | /* |
---|
337 | 419 | * Ensure the addition to the reorder list is ordered correctly |
---|
338 | 420 | * with the trylock of pd->lock in padata_reorder. Pairs with smp_mb |
---|
339 | 421 | * in padata_reorder. |
---|
340 | 422 | */ |
---|
341 | | - smp_mb__after_atomic(); |
---|
| 423 | + smp_mb(); |
---|
342 | 424 | |
---|
343 | 425 | padata_reorder(pd); |
---|
344 | 426 | } |
---|
345 | 427 | EXPORT_SYMBOL(padata_do_serial); |
---|
346 | 428 | |
---|
347 | | -static int padata_setup_cpumasks(struct parallel_data *pd, |
---|
348 | | - const struct cpumask *pcpumask, |
---|
349 | | - const struct cpumask *cbcpumask) |
---|
| 429 | +static int padata_setup_cpumasks(struct padata_instance *pinst) |
---|
350 | 430 | { |
---|
351 | | - if (!alloc_cpumask_var(&pd->cpumask.pcpu, GFP_KERNEL)) |
---|
| 431 | + struct workqueue_attrs *attrs; |
---|
| 432 | + int err; |
---|
| 433 | + |
---|
| 434 | + attrs = alloc_workqueue_attrs(); |
---|
| 435 | + if (!attrs) |
---|
352 | 436 | return -ENOMEM; |
---|
353 | 437 | |
---|
354 | | - cpumask_and(pd->cpumask.pcpu, pcpumask, cpu_online_mask); |
---|
355 | | - if (!alloc_cpumask_var(&pd->cpumask.cbcpu, GFP_KERNEL)) { |
---|
356 | | - free_cpumask_var(pd->cpumask.pcpu); |
---|
357 | | - return -ENOMEM; |
---|
| 438 | + /* Restrict parallel_wq workers to pd->cpumask.pcpu. */ |
---|
| 439 | + cpumask_copy(attrs->cpumask, pinst->cpumask.pcpu); |
---|
| 440 | + err = apply_workqueue_attrs(pinst->parallel_wq, attrs); |
---|
| 441 | + free_workqueue_attrs(attrs); |
---|
| 442 | + |
---|
| 443 | + return err; |
---|
| 444 | +} |
---|
| 445 | + |
---|
| 446 | +static void __init padata_mt_helper(struct work_struct *w) |
---|
| 447 | +{ |
---|
| 448 | + struct padata_work *pw = container_of(w, struct padata_work, pw_work); |
---|
| 449 | + struct padata_mt_job_state *ps = pw->pw_data; |
---|
| 450 | + struct padata_mt_job *job = ps->job; |
---|
| 451 | + bool done; |
---|
| 452 | + |
---|
| 453 | + spin_lock(&ps->lock); |
---|
| 454 | + |
---|
| 455 | + while (job->size > 0) { |
---|
| 456 | + unsigned long start, size, end; |
---|
| 457 | + |
---|
| 458 | + start = job->start; |
---|
| 459 | + /* So end is chunk size aligned if enough work remains. */ |
---|
| 460 | + size = roundup(start + 1, ps->chunk_size) - start; |
---|
| 461 | + size = min(size, job->size); |
---|
| 462 | + end = start + size; |
---|
| 463 | + |
---|
| 464 | + job->start = end; |
---|
| 465 | + job->size -= size; |
---|
| 466 | + |
---|
| 467 | + spin_unlock(&ps->lock); |
---|
| 468 | + job->thread_fn(start, end, job->fn_arg); |
---|
| 469 | + spin_lock(&ps->lock); |
---|
358 | 470 | } |
---|
359 | 471 | |
---|
360 | | - cpumask_and(pd->cpumask.cbcpu, cbcpumask, cpu_online_mask); |
---|
361 | | - return 0; |
---|
| 472 | + ++ps->nworks_fini; |
---|
| 473 | + done = (ps->nworks_fini == ps->nworks); |
---|
| 474 | + spin_unlock(&ps->lock); |
---|
| 475 | + |
---|
| 476 | + if (done) |
---|
| 477 | + complete(&ps->completion); |
---|
| 478 | +} |
---|
| 479 | + |
---|
| 480 | +/** |
---|
| 481 | + * padata_do_multithreaded - run a multithreaded job |
---|
| 482 | + * @job: Description of the job. |
---|
| 483 | + * |
---|
| 484 | + * See the definition of struct padata_mt_job for more details. |
---|
| 485 | + */ |
---|
| 486 | +void __init padata_do_multithreaded(struct padata_mt_job *job) |
---|
| 487 | +{ |
---|
| 488 | + /* In case threads finish at different times. */ |
---|
| 489 | + static const unsigned long load_balance_factor = 4; |
---|
| 490 | + struct padata_work my_work, *pw; |
---|
| 491 | + struct padata_mt_job_state ps; |
---|
| 492 | + LIST_HEAD(works); |
---|
| 493 | + int nworks; |
---|
| 494 | + |
---|
| 495 | + if (job->size == 0) |
---|
| 496 | + return; |
---|
| 497 | + |
---|
| 498 | + /* Ensure at least one thread when size < min_chunk. */ |
---|
| 499 | + nworks = max(job->size / job->min_chunk, 1ul); |
---|
| 500 | + nworks = min(nworks, job->max_threads); |
---|
| 501 | + |
---|
| 502 | + if (nworks == 1) { |
---|
| 503 | + /* Single thread, no coordination needed, cut to the chase. */ |
---|
| 504 | + job->thread_fn(job->start, job->start + job->size, job->fn_arg); |
---|
| 505 | + return; |
---|
| 506 | + } |
---|
| 507 | + |
---|
| 508 | + spin_lock_init(&ps.lock); |
---|
| 509 | + init_completion(&ps.completion); |
---|
| 510 | + ps.job = job; |
---|
| 511 | + ps.nworks = padata_work_alloc_mt(nworks, &ps, &works); |
---|
| 512 | + ps.nworks_fini = 0; |
---|
| 513 | + |
---|
| 514 | + /* |
---|
| 515 | + * Chunk size is the amount of work a helper does per call to the |
---|
| 516 | + * thread function. Load balance large jobs between threads by |
---|
| 517 | + * increasing the number of chunks, guarantee at least the minimum |
---|
| 518 | + * chunk size from the caller, and honor the caller's alignment. |
---|
| 519 | + */ |
---|
| 520 | + ps.chunk_size = job->size / (ps.nworks * load_balance_factor); |
---|
| 521 | + ps.chunk_size = max(ps.chunk_size, job->min_chunk); |
---|
| 522 | + ps.chunk_size = roundup(ps.chunk_size, job->align); |
---|
| 523 | + |
---|
| 524 | + list_for_each_entry(pw, &works, pw_list) |
---|
| 525 | + queue_work(system_unbound_wq, &pw->pw_work); |
---|
| 526 | + |
---|
| 527 | + /* Use the current thread, which saves starting a workqueue worker. */ |
---|
| 528 | + padata_work_init(&my_work, padata_mt_helper, &ps, PADATA_WORK_ONSTACK); |
---|
| 529 | + padata_mt_helper(&my_work.pw_work); |
---|
| 530 | + |
---|
| 531 | + /* Wait for all the helpers to finish. */ |
---|
| 532 | + wait_for_completion(&ps.completion); |
---|
| 533 | + |
---|
| 534 | + destroy_work_on_stack(&my_work.pw_work); |
---|
| 535 | + padata_works_free(&works); |
---|
362 | 536 | } |
---|
363 | 537 | |
---|
364 | 538 | static void __padata_list_init(struct padata_list *pd_list) |
---|
.. | .. |
---|
381 | 555 | } |
---|
382 | 556 | } |
---|
383 | 557 | |
---|
384 | | -/* Initialize all percpu queues used by parallel workers */ |
---|
385 | | -static void padata_init_pqueues(struct parallel_data *pd) |
---|
| 558 | +/* Initialize per-CPU reorder lists */ |
---|
| 559 | +static void padata_init_reorder_list(struct parallel_data *pd) |
---|
386 | 560 | { |
---|
387 | | - int cpu_index, cpu; |
---|
388 | | - struct padata_parallel_queue *pqueue; |
---|
| 561 | + int cpu; |
---|
| 562 | + struct padata_list *list; |
---|
389 | 563 | |
---|
390 | | - cpu_index = 0; |
---|
391 | | - for_each_possible_cpu(cpu) { |
---|
392 | | - pqueue = per_cpu_ptr(pd->pqueue, cpu); |
---|
393 | | - |
---|
394 | | - if (!cpumask_test_cpu(cpu, pd->cpumask.pcpu)) { |
---|
395 | | - pqueue->cpu_index = -1; |
---|
396 | | - continue; |
---|
397 | | - } |
---|
398 | | - |
---|
399 | | - pqueue->cpu_index = cpu_index; |
---|
400 | | - cpu_index++; |
---|
401 | | - |
---|
402 | | - __padata_list_init(&pqueue->reorder); |
---|
403 | | - __padata_list_init(&pqueue->parallel); |
---|
404 | | - INIT_WORK(&pqueue->work, padata_parallel_worker); |
---|
405 | | - atomic_set(&pqueue->num_obj, 0); |
---|
| 564 | + for_each_cpu(cpu, pd->cpumask.pcpu) { |
---|
| 565 | + list = per_cpu_ptr(pd->reorder_list, cpu); |
---|
| 566 | + __padata_list_init(list); |
---|
406 | 567 | } |
---|
407 | 568 | } |
---|
408 | 569 | |
---|
409 | 570 | /* Allocate and initialize the internal cpumask dependend resources. */ |
---|
410 | | -static struct parallel_data *padata_alloc_pd(struct padata_instance *pinst, |
---|
411 | | - const struct cpumask *pcpumask, |
---|
412 | | - const struct cpumask *cbcpumask) |
---|
| 571 | +static struct parallel_data *padata_alloc_pd(struct padata_shell *ps) |
---|
413 | 572 | { |
---|
| 573 | + struct padata_instance *pinst = ps->pinst; |
---|
414 | 574 | struct parallel_data *pd; |
---|
415 | 575 | |
---|
416 | 576 | pd = kzalloc(sizeof(struct parallel_data), GFP_KERNEL); |
---|
417 | 577 | if (!pd) |
---|
418 | 578 | goto err; |
---|
419 | 579 | |
---|
420 | | - pd->pqueue = alloc_percpu(struct padata_parallel_queue); |
---|
421 | | - if (!pd->pqueue) |
---|
| 580 | + pd->reorder_list = alloc_percpu(struct padata_list); |
---|
| 581 | + if (!pd->reorder_list) |
---|
422 | 582 | goto err_free_pd; |
---|
423 | 583 | |
---|
424 | 584 | pd->squeue = alloc_percpu(struct padata_serial_queue); |
---|
425 | 585 | if (!pd->squeue) |
---|
426 | | - goto err_free_pqueue; |
---|
427 | | - if (padata_setup_cpumasks(pd, pcpumask, cbcpumask) < 0) |
---|
428 | | - goto err_free_squeue; |
---|
| 586 | + goto err_free_reorder_list; |
---|
429 | 587 | |
---|
430 | | - padata_init_pqueues(pd); |
---|
| 588 | + pd->ps = ps; |
---|
| 589 | + |
---|
| 590 | + if (!alloc_cpumask_var(&pd->cpumask.pcpu, GFP_KERNEL)) |
---|
| 591 | + goto err_free_squeue; |
---|
| 592 | + if (!alloc_cpumask_var(&pd->cpumask.cbcpu, GFP_KERNEL)) |
---|
| 593 | + goto err_free_pcpu; |
---|
| 594 | + |
---|
| 595 | + cpumask_and(pd->cpumask.pcpu, pinst->cpumask.pcpu, cpu_online_mask); |
---|
| 596 | + cpumask_and(pd->cpumask.cbcpu, pinst->cpumask.cbcpu, cpu_online_mask); |
---|
| 597 | + |
---|
| 598 | + padata_init_reorder_list(pd); |
---|
431 | 599 | padata_init_squeues(pd); |
---|
432 | | - atomic_set(&pd->seq_nr, -1); |
---|
433 | | - atomic_set(&pd->reorder_objects, 0); |
---|
| 600 | + pd->seq_nr = -1; |
---|
434 | 601 | atomic_set(&pd->refcnt, 1); |
---|
435 | | - pd->pinst = pinst; |
---|
436 | 602 | spin_lock_init(&pd->lock); |
---|
437 | 603 | pd->cpu = cpumask_first(pd->cpumask.pcpu); |
---|
438 | 604 | INIT_WORK(&pd->reorder_work, invoke_padata_reorder); |
---|
439 | 605 | |
---|
440 | 606 | return pd; |
---|
441 | 607 | |
---|
| 608 | +err_free_pcpu: |
---|
| 609 | + free_cpumask_var(pd->cpumask.pcpu); |
---|
442 | 610 | err_free_squeue: |
---|
443 | 611 | free_percpu(pd->squeue); |
---|
444 | | -err_free_pqueue: |
---|
445 | | - free_percpu(pd->pqueue); |
---|
| 612 | +err_free_reorder_list: |
---|
| 613 | + free_percpu(pd->reorder_list); |
---|
446 | 614 | err_free_pd: |
---|
447 | 615 | kfree(pd); |
---|
448 | 616 | err: |
---|
.. | .. |
---|
453 | 621 | { |
---|
454 | 622 | free_cpumask_var(pd->cpumask.pcpu); |
---|
455 | 623 | free_cpumask_var(pd->cpumask.cbcpu); |
---|
456 | | - free_percpu(pd->pqueue); |
---|
| 624 | + free_percpu(pd->reorder_list); |
---|
457 | 625 | free_percpu(pd->squeue); |
---|
458 | 626 | kfree(pd); |
---|
459 | 627 | } |
---|
.. | .. |
---|
474 | 642 | } |
---|
475 | 643 | |
---|
476 | 644 | /* Replace the internal control structure with a new one. */ |
---|
477 | | -static void padata_replace(struct padata_instance *pinst, |
---|
478 | | - struct parallel_data *pd_new) |
---|
| 645 | +static int padata_replace_one(struct padata_shell *ps) |
---|
479 | 646 | { |
---|
480 | | - struct parallel_data *pd_old = pinst->pd; |
---|
481 | | - int notification_mask = 0; |
---|
| 647 | + struct parallel_data *pd_new; |
---|
| 648 | + |
---|
| 649 | + pd_new = padata_alloc_pd(ps); |
---|
| 650 | + if (!pd_new) |
---|
| 651 | + return -ENOMEM; |
---|
| 652 | + |
---|
| 653 | + ps->opd = rcu_dereference_protected(ps->pd, 1); |
---|
| 654 | + rcu_assign_pointer(ps->pd, pd_new); |
---|
| 655 | + |
---|
| 656 | + return 0; |
---|
| 657 | +} |
---|
| 658 | + |
---|
| 659 | +static int padata_replace(struct padata_instance *pinst) |
---|
| 660 | +{ |
---|
| 661 | + struct padata_shell *ps; |
---|
| 662 | + int err = 0; |
---|
482 | 663 | |
---|
483 | 664 | pinst->flags |= PADATA_RESET; |
---|
484 | 665 | |
---|
485 | | - rcu_assign_pointer(pinst->pd, pd_new); |
---|
| 666 | + list_for_each_entry(ps, &pinst->pslist, list) { |
---|
| 667 | + err = padata_replace_one(ps); |
---|
| 668 | + if (err) |
---|
| 669 | + break; |
---|
| 670 | + } |
---|
486 | 671 | |
---|
487 | 672 | synchronize_rcu(); |
---|
488 | 673 | |
---|
489 | | - if (!cpumask_equal(pd_old->cpumask.pcpu, pd_new->cpumask.pcpu)) |
---|
490 | | - notification_mask |= PADATA_CPU_PARALLEL; |
---|
491 | | - if (!cpumask_equal(pd_old->cpumask.cbcpu, pd_new->cpumask.cbcpu)) |
---|
492 | | - notification_mask |= PADATA_CPU_SERIAL; |
---|
493 | | - |
---|
494 | | - if (atomic_dec_and_test(&pd_old->refcnt)) |
---|
495 | | - padata_free_pd(pd_old); |
---|
496 | | - |
---|
497 | | - if (notification_mask) |
---|
498 | | - blocking_notifier_call_chain(&pinst->cpumask_change_notifier, |
---|
499 | | - notification_mask, |
---|
500 | | - &pd_new->cpumask); |
---|
| 674 | + list_for_each_entry_continue_reverse(ps, &pinst->pslist, list) |
---|
| 675 | + if (atomic_dec_and_test(&ps->opd->refcnt)) |
---|
| 676 | + padata_free_pd(ps->opd); |
---|
501 | 677 | |
---|
502 | 678 | pinst->flags &= ~PADATA_RESET; |
---|
503 | | -} |
---|
504 | 679 | |
---|
505 | | -/** |
---|
506 | | - * padata_register_cpumask_notifier - Registers a notifier that will be called |
---|
507 | | - * if either pcpu or cbcpu or both cpumasks change. |
---|
508 | | - * |
---|
509 | | - * @pinst: A poineter to padata instance |
---|
510 | | - * @nblock: A pointer to notifier block. |
---|
511 | | - */ |
---|
512 | | -int padata_register_cpumask_notifier(struct padata_instance *pinst, |
---|
513 | | - struct notifier_block *nblock) |
---|
514 | | -{ |
---|
515 | | - return blocking_notifier_chain_register(&pinst->cpumask_change_notifier, |
---|
516 | | - nblock); |
---|
| 680 | + return err; |
---|
517 | 681 | } |
---|
518 | | -EXPORT_SYMBOL(padata_register_cpumask_notifier); |
---|
519 | | - |
---|
520 | | -/** |
---|
521 | | - * padata_unregister_cpumask_notifier - Unregisters cpumask notifier |
---|
522 | | - * registered earlier using padata_register_cpumask_notifier |
---|
523 | | - * |
---|
524 | | - * @pinst: A pointer to data instance. |
---|
525 | | - * @nlock: A pointer to notifier block. |
---|
526 | | - */ |
---|
527 | | -int padata_unregister_cpumask_notifier(struct padata_instance *pinst, |
---|
528 | | - struct notifier_block *nblock) |
---|
529 | | -{ |
---|
530 | | - return blocking_notifier_chain_unregister( |
---|
531 | | - &pinst->cpumask_change_notifier, |
---|
532 | | - nblock); |
---|
533 | | -} |
---|
534 | | -EXPORT_SYMBOL(padata_unregister_cpumask_notifier); |
---|
535 | | - |
---|
536 | 682 | |
---|
537 | 683 | /* If cpumask contains no active cpu, we mark the instance as invalid. */ |
---|
538 | 684 | static bool padata_validate_cpumask(struct padata_instance *pinst, |
---|
.. | .. |
---|
552 | 698 | cpumask_var_t cbcpumask) |
---|
553 | 699 | { |
---|
554 | 700 | int valid; |
---|
555 | | - struct parallel_data *pd; |
---|
| 701 | + int err; |
---|
556 | 702 | |
---|
557 | 703 | valid = padata_validate_cpumask(pinst, pcpumask); |
---|
558 | 704 | if (!valid) { |
---|
.. | .. |
---|
565 | 711 | __padata_stop(pinst); |
---|
566 | 712 | |
---|
567 | 713 | out_replace: |
---|
568 | | - pd = padata_alloc_pd(pinst, pcpumask, cbcpumask); |
---|
569 | | - if (!pd) |
---|
570 | | - return -ENOMEM; |
---|
571 | | - |
---|
572 | 714 | cpumask_copy(pinst->cpumask.pcpu, pcpumask); |
---|
573 | 715 | cpumask_copy(pinst->cpumask.cbcpu, cbcpumask); |
---|
574 | 716 | |
---|
575 | | - padata_replace(pinst, pd); |
---|
| 717 | + err = padata_setup_cpumasks(pinst) ?: padata_replace(pinst); |
---|
576 | 718 | |
---|
577 | 719 | if (valid) |
---|
578 | 720 | __padata_start(pinst); |
---|
579 | 721 | |
---|
580 | | - return 0; |
---|
| 722 | + return err; |
---|
581 | 723 | } |
---|
582 | 724 | |
---|
583 | 725 | /** |
---|
584 | | - * padata_set_cpumask: Sets specified by @cpumask_type cpumask to the value |
---|
585 | | - * equivalent to @cpumask. |
---|
586 | | - * |
---|
| 726 | + * padata_set_cpumask - Sets specified by @cpumask_type cpumask to the value |
---|
| 727 | + * equivalent to @cpumask. |
---|
587 | 728 | * @pinst: padata instance |
---|
588 | 729 | * @cpumask_type: PADATA_CPU_SERIAL or PADATA_CPU_PARALLEL corresponding |
---|
589 | 730 | * to parallel and serial cpumasks respectively. |
---|
590 | 731 | * @cpumask: the cpumask to use |
---|
| 732 | + * |
---|
| 733 | + * Return: 0 on success or negative error code |
---|
591 | 734 | */ |
---|
592 | 735 | int padata_set_cpumask(struct padata_instance *pinst, int cpumask_type, |
---|
593 | 736 | cpumask_var_t cpumask) |
---|
.. | .. |
---|
621 | 764 | } |
---|
622 | 765 | EXPORT_SYMBOL(padata_set_cpumask); |
---|
623 | 766 | |
---|
624 | | -/** |
---|
625 | | - * padata_start - start the parallel processing |
---|
626 | | - * |
---|
627 | | - * @pinst: padata instance to start |
---|
628 | | - */ |
---|
629 | | -int padata_start(struct padata_instance *pinst) |
---|
630 | | -{ |
---|
631 | | - int err = 0; |
---|
632 | | - |
---|
633 | | - mutex_lock(&pinst->lock); |
---|
634 | | - |
---|
635 | | - if (pinst->flags & PADATA_INVALID) |
---|
636 | | - err = -EINVAL; |
---|
637 | | - |
---|
638 | | - __padata_start(pinst); |
---|
639 | | - |
---|
640 | | - mutex_unlock(&pinst->lock); |
---|
641 | | - |
---|
642 | | - return err; |
---|
643 | | -} |
---|
644 | | -EXPORT_SYMBOL(padata_start); |
---|
645 | | - |
---|
646 | | -/** |
---|
647 | | - * padata_stop - stop the parallel processing |
---|
648 | | - * |
---|
649 | | - * @pinst: padata instance to stop |
---|
650 | | - */ |
---|
651 | | -void padata_stop(struct padata_instance *pinst) |
---|
652 | | -{ |
---|
653 | | - mutex_lock(&pinst->lock); |
---|
654 | | - __padata_stop(pinst); |
---|
655 | | - mutex_unlock(&pinst->lock); |
---|
656 | | -} |
---|
657 | | -EXPORT_SYMBOL(padata_stop); |
---|
658 | | - |
---|
659 | 767 | #ifdef CONFIG_HOTPLUG_CPU |
---|
660 | 768 | |
---|
661 | 769 | static int __padata_add_cpu(struct padata_instance *pinst, int cpu) |
---|
662 | 770 | { |
---|
663 | | - struct parallel_data *pd; |
---|
| 771 | + int err = 0; |
---|
664 | 772 | |
---|
665 | 773 | if (cpumask_test_cpu(cpu, cpu_online_mask)) { |
---|
666 | | - pd = padata_alloc_pd(pinst, pinst->cpumask.pcpu, |
---|
667 | | - pinst->cpumask.cbcpu); |
---|
668 | | - if (!pd) |
---|
669 | | - return -ENOMEM; |
---|
670 | | - |
---|
671 | | - padata_replace(pinst, pd); |
---|
| 774 | + err = padata_replace(pinst); |
---|
672 | 775 | |
---|
673 | 776 | if (padata_validate_cpumask(pinst, pinst->cpumask.pcpu) && |
---|
674 | 777 | padata_validate_cpumask(pinst, pinst->cpumask.cbcpu)) |
---|
675 | 778 | __padata_start(pinst); |
---|
676 | 779 | } |
---|
677 | 780 | |
---|
678 | | - return 0; |
---|
| 781 | + return err; |
---|
679 | 782 | } |
---|
680 | 783 | |
---|
681 | 784 | static int __padata_remove_cpu(struct padata_instance *pinst, int cpu) |
---|
682 | 785 | { |
---|
683 | | - struct parallel_data *pd = NULL; |
---|
| 786 | + int err = 0; |
---|
684 | 787 | |
---|
685 | | - if (cpumask_test_cpu(cpu, cpu_online_mask)) { |
---|
686 | | - |
---|
| 788 | + if (!cpumask_test_cpu(cpu, cpu_online_mask)) { |
---|
687 | 789 | if (!padata_validate_cpumask(pinst, pinst->cpumask.pcpu) || |
---|
688 | 790 | !padata_validate_cpumask(pinst, pinst->cpumask.cbcpu)) |
---|
689 | 791 | __padata_stop(pinst); |
---|
690 | 792 | |
---|
691 | | - pd = padata_alloc_pd(pinst, pinst->cpumask.pcpu, |
---|
692 | | - pinst->cpumask.cbcpu); |
---|
693 | | - if (!pd) |
---|
694 | | - return -ENOMEM; |
---|
695 | | - |
---|
696 | | - padata_replace(pinst, pd); |
---|
697 | | - |
---|
698 | | - cpumask_clear_cpu(cpu, pd->cpumask.cbcpu); |
---|
699 | | - cpumask_clear_cpu(cpu, pd->cpumask.pcpu); |
---|
| 793 | + err = padata_replace(pinst); |
---|
700 | 794 | } |
---|
701 | | - |
---|
702 | | - return 0; |
---|
703 | | -} |
---|
704 | | - |
---|
705 | | - /** |
---|
706 | | - * padata_remove_cpu - remove a cpu from the one or both(serial and parallel) |
---|
707 | | - * padata cpumasks. |
---|
708 | | - * |
---|
709 | | - * @pinst: padata instance |
---|
710 | | - * @cpu: cpu to remove |
---|
711 | | - * @mask: bitmask specifying from which cpumask @cpu should be removed |
---|
712 | | - * The @mask may be any combination of the following flags: |
---|
713 | | - * PADATA_CPU_SERIAL - serial cpumask |
---|
714 | | - * PADATA_CPU_PARALLEL - parallel cpumask |
---|
715 | | - */ |
---|
716 | | -int padata_remove_cpu(struct padata_instance *pinst, int cpu, int mask) |
---|
717 | | -{ |
---|
718 | | - int err; |
---|
719 | | - |
---|
720 | | - if (!(mask & (PADATA_CPU_SERIAL | PADATA_CPU_PARALLEL))) |
---|
721 | | - return -EINVAL; |
---|
722 | | - |
---|
723 | | - mutex_lock(&pinst->lock); |
---|
724 | | - |
---|
725 | | - get_online_cpus(); |
---|
726 | | - if (mask & PADATA_CPU_SERIAL) |
---|
727 | | - cpumask_clear_cpu(cpu, pinst->cpumask.cbcpu); |
---|
728 | | - if (mask & PADATA_CPU_PARALLEL) |
---|
729 | | - cpumask_clear_cpu(cpu, pinst->cpumask.pcpu); |
---|
730 | | - |
---|
731 | | - err = __padata_remove_cpu(pinst, cpu); |
---|
732 | | - put_online_cpus(); |
---|
733 | | - |
---|
734 | | - mutex_unlock(&pinst->lock); |
---|
735 | 795 | |
---|
736 | 796 | return err; |
---|
737 | 797 | } |
---|
738 | | -EXPORT_SYMBOL(padata_remove_cpu); |
---|
739 | 798 | |
---|
740 | 799 | static inline int pinst_has_cpu(struct padata_instance *pinst, int cpu) |
---|
741 | 800 | { |
---|
.. | .. |
---|
748 | 807 | struct padata_instance *pinst; |
---|
749 | 808 | int ret; |
---|
750 | 809 | |
---|
751 | | - pinst = hlist_entry_safe(node, struct padata_instance, node); |
---|
| 810 | + pinst = hlist_entry_safe(node, struct padata_instance, cpu_online_node); |
---|
752 | 811 | if (!pinst_has_cpu(pinst, cpu)) |
---|
753 | 812 | return 0; |
---|
754 | 813 | |
---|
.. | .. |
---|
758 | 817 | return ret; |
---|
759 | 818 | } |
---|
760 | 819 | |
---|
761 | | -static int padata_cpu_prep_down(unsigned int cpu, struct hlist_node *node) |
---|
| 820 | +static int padata_cpu_dead(unsigned int cpu, struct hlist_node *node) |
---|
762 | 821 | { |
---|
763 | 822 | struct padata_instance *pinst; |
---|
764 | 823 | int ret; |
---|
765 | 824 | |
---|
766 | | - pinst = hlist_entry_safe(node, struct padata_instance, node); |
---|
| 825 | + pinst = hlist_entry_safe(node, struct padata_instance, cpu_dead_node); |
---|
767 | 826 | if (!pinst_has_cpu(pinst, cpu)) |
---|
768 | 827 | return 0; |
---|
769 | 828 | |
---|
.. | .. |
---|
779 | 838 | static void __padata_free(struct padata_instance *pinst) |
---|
780 | 839 | { |
---|
781 | 840 | #ifdef CONFIG_HOTPLUG_CPU |
---|
782 | | - cpuhp_state_remove_instance_nocalls(hp_online, &pinst->node); |
---|
| 841 | + cpuhp_state_remove_instance_nocalls(CPUHP_PADATA_DEAD, |
---|
| 842 | + &pinst->cpu_dead_node); |
---|
| 843 | + cpuhp_state_remove_instance_nocalls(hp_online, &pinst->cpu_online_node); |
---|
783 | 844 | #endif |
---|
784 | 845 | |
---|
785 | | - padata_stop(pinst); |
---|
786 | | - padata_free_pd(pinst->pd); |
---|
| 846 | + WARN_ON(!list_empty(&pinst->pslist)); |
---|
| 847 | + |
---|
787 | 848 | free_cpumask_var(pinst->cpumask.pcpu); |
---|
788 | 849 | free_cpumask_var(pinst->cpumask.cbcpu); |
---|
| 850 | + destroy_workqueue(pinst->serial_wq); |
---|
| 851 | + destroy_workqueue(pinst->parallel_wq); |
---|
789 | 852 | kfree(pinst); |
---|
790 | 853 | } |
---|
791 | 854 | |
---|
.. | .. |
---|
872 | 935 | ¶llel_cpumask_attr.attr, |
---|
873 | 936 | NULL, |
---|
874 | 937 | }; |
---|
| 938 | +ATTRIBUTE_GROUPS(padata_default); |
---|
875 | 939 | |
---|
876 | 940 | static ssize_t padata_sysfs_show(struct kobject *kobj, |
---|
877 | 941 | struct attribute *attr, char *buf) |
---|
.. | .. |
---|
910 | 974 | |
---|
911 | 975 | static struct kobj_type padata_attr_type = { |
---|
912 | 976 | .sysfs_ops = &padata_sysfs_ops, |
---|
913 | | - .default_attrs = padata_default_attrs, |
---|
| 977 | + .default_groups = padata_default_groups, |
---|
914 | 978 | .release = padata_sysfs_release, |
---|
915 | 979 | }; |
---|
916 | 980 | |
---|
917 | 981 | /** |
---|
918 | | - * padata_alloc - allocate and initialize a padata instance and specify |
---|
919 | | - * cpumasks for serial and parallel workers. |
---|
| 982 | + * padata_alloc - allocate and initialize a padata instance |
---|
| 983 | + * @name: used to identify the instance |
---|
920 | 984 | * |
---|
921 | | - * @wq: workqueue to use for the allocated padata instance |
---|
922 | | - * @pcpumask: cpumask that will be used for padata parallelization |
---|
923 | | - * @cbcpumask: cpumask that will be used for padata serialization |
---|
924 | | - * |
---|
925 | | - * Must be called from a cpus_read_lock() protected region |
---|
| 985 | + * Return: new instance on success, NULL on error |
---|
926 | 986 | */ |
---|
927 | | -static struct padata_instance *padata_alloc(struct workqueue_struct *wq, |
---|
928 | | - const struct cpumask *pcpumask, |
---|
929 | | - const struct cpumask *cbcpumask) |
---|
| 987 | +struct padata_instance *padata_alloc(const char *name) |
---|
930 | 988 | { |
---|
931 | 989 | struct padata_instance *pinst; |
---|
932 | | - struct parallel_data *pd = NULL; |
---|
933 | 990 | |
---|
934 | 991 | pinst = kzalloc(sizeof(struct padata_instance), GFP_KERNEL); |
---|
935 | 992 | if (!pinst) |
---|
936 | 993 | goto err; |
---|
937 | 994 | |
---|
938 | | - if (!alloc_cpumask_var(&pinst->cpumask.pcpu, GFP_KERNEL)) |
---|
| 995 | + pinst->parallel_wq = alloc_workqueue("%s_parallel", WQ_UNBOUND, 0, |
---|
| 996 | + name); |
---|
| 997 | + if (!pinst->parallel_wq) |
---|
939 | 998 | goto err_free_inst; |
---|
| 999 | + |
---|
| 1000 | + get_online_cpus(); |
---|
| 1001 | + |
---|
| 1002 | + pinst->serial_wq = alloc_workqueue("%s_serial", WQ_MEM_RECLAIM | |
---|
| 1003 | + WQ_CPU_INTENSIVE, 1, name); |
---|
| 1004 | + if (!pinst->serial_wq) |
---|
| 1005 | + goto err_put_cpus; |
---|
| 1006 | + |
---|
| 1007 | + if (!alloc_cpumask_var(&pinst->cpumask.pcpu, GFP_KERNEL)) |
---|
| 1008 | + goto err_free_serial_wq; |
---|
940 | 1009 | if (!alloc_cpumask_var(&pinst->cpumask.cbcpu, GFP_KERNEL)) { |
---|
941 | 1010 | free_cpumask_var(pinst->cpumask.pcpu); |
---|
942 | | - goto err_free_inst; |
---|
| 1011 | + goto err_free_serial_wq; |
---|
943 | 1012 | } |
---|
944 | | - if (!padata_validate_cpumask(pinst, pcpumask) || |
---|
945 | | - !padata_validate_cpumask(pinst, cbcpumask)) |
---|
| 1013 | + |
---|
| 1014 | + INIT_LIST_HEAD(&pinst->pslist); |
---|
| 1015 | + |
---|
| 1016 | + cpumask_copy(pinst->cpumask.pcpu, cpu_possible_mask); |
---|
| 1017 | + cpumask_copy(pinst->cpumask.cbcpu, cpu_possible_mask); |
---|
| 1018 | + |
---|
| 1019 | + if (padata_setup_cpumasks(pinst)) |
---|
946 | 1020 | goto err_free_masks; |
---|
947 | 1021 | |
---|
948 | | - pd = padata_alloc_pd(pinst, pcpumask, cbcpumask); |
---|
949 | | - if (!pd) |
---|
950 | | - goto err_free_masks; |
---|
| 1022 | + __padata_start(pinst); |
---|
951 | 1023 | |
---|
952 | | - rcu_assign_pointer(pinst->pd, pd); |
---|
953 | | - |
---|
954 | | - pinst->wq = wq; |
---|
955 | | - |
---|
956 | | - cpumask_copy(pinst->cpumask.pcpu, pcpumask); |
---|
957 | | - cpumask_copy(pinst->cpumask.cbcpu, cbcpumask); |
---|
958 | | - |
---|
959 | | - pinst->flags = 0; |
---|
960 | | - |
---|
961 | | - BLOCKING_INIT_NOTIFIER_HEAD(&pinst->cpumask_change_notifier); |
---|
962 | 1024 | kobject_init(&pinst->kobj, &padata_attr_type); |
---|
963 | 1025 | mutex_init(&pinst->lock); |
---|
964 | 1026 | |
---|
965 | 1027 | #ifdef CONFIG_HOTPLUG_CPU |
---|
966 | | - cpuhp_state_add_instance_nocalls_cpuslocked(hp_online, &pinst->node); |
---|
| 1028 | + cpuhp_state_add_instance_nocalls_cpuslocked(hp_online, |
---|
| 1029 | + &pinst->cpu_online_node); |
---|
| 1030 | + cpuhp_state_add_instance_nocalls_cpuslocked(CPUHP_PADATA_DEAD, |
---|
| 1031 | + &pinst->cpu_dead_node); |
---|
967 | 1032 | #endif |
---|
| 1033 | + |
---|
| 1034 | + put_online_cpus(); |
---|
| 1035 | + |
---|
968 | 1036 | return pinst; |
---|
969 | 1037 | |
---|
970 | 1038 | err_free_masks: |
---|
971 | 1039 | free_cpumask_var(pinst->cpumask.pcpu); |
---|
972 | 1040 | free_cpumask_var(pinst->cpumask.cbcpu); |
---|
| 1041 | +err_free_serial_wq: |
---|
| 1042 | + destroy_workqueue(pinst->serial_wq); |
---|
| 1043 | +err_put_cpus: |
---|
| 1044 | + put_online_cpus(); |
---|
| 1045 | + destroy_workqueue(pinst->parallel_wq); |
---|
973 | 1046 | err_free_inst: |
---|
974 | 1047 | kfree(pinst); |
---|
975 | 1048 | err: |
---|
976 | 1049 | return NULL; |
---|
977 | 1050 | } |
---|
978 | | - |
---|
979 | | -/** |
---|
980 | | - * padata_alloc_possible - Allocate and initialize padata instance. |
---|
981 | | - * Use the cpu_possible_mask for serial and |
---|
982 | | - * parallel workers. |
---|
983 | | - * |
---|
984 | | - * @wq: workqueue to use for the allocated padata instance |
---|
985 | | - * |
---|
986 | | - * Must be called from a cpus_read_lock() protected region |
---|
987 | | - */ |
---|
988 | | -struct padata_instance *padata_alloc_possible(struct workqueue_struct *wq) |
---|
989 | | -{ |
---|
990 | | - lockdep_assert_cpus_held(); |
---|
991 | | - return padata_alloc(wq, cpu_possible_mask, cpu_possible_mask); |
---|
992 | | -} |
---|
993 | | -EXPORT_SYMBOL(padata_alloc_possible); |
---|
| 1051 | +EXPORT_SYMBOL(padata_alloc); |
---|
994 | 1052 | |
---|
995 | 1053 | /** |
---|
996 | 1054 | * padata_free - free a padata instance |
---|
997 | 1055 | * |
---|
998 | | - * @padata_inst: padata instance to free |
---|
| 1056 | + * @pinst: padata instance to free |
---|
999 | 1057 | */ |
---|
1000 | 1058 | void padata_free(struct padata_instance *pinst) |
---|
1001 | 1059 | { |
---|
.. | .. |
---|
1003 | 1061 | } |
---|
1004 | 1062 | EXPORT_SYMBOL(padata_free); |
---|
1005 | 1063 | |
---|
1006 | | -#ifdef CONFIG_HOTPLUG_CPU |
---|
1007 | | - |
---|
1008 | | -static __init int padata_driver_init(void) |
---|
| 1064 | +/** |
---|
| 1065 | + * padata_alloc_shell - Allocate and initialize padata shell. |
---|
| 1066 | + * |
---|
| 1067 | + * @pinst: Parent padata_instance object. |
---|
| 1068 | + * |
---|
| 1069 | + * Return: new shell on success, NULL on error |
---|
| 1070 | + */ |
---|
| 1071 | +struct padata_shell *padata_alloc_shell(struct padata_instance *pinst) |
---|
1009 | 1072 | { |
---|
| 1073 | + struct parallel_data *pd; |
---|
| 1074 | + struct padata_shell *ps; |
---|
| 1075 | + |
---|
| 1076 | + ps = kzalloc(sizeof(*ps), GFP_KERNEL); |
---|
| 1077 | + if (!ps) |
---|
| 1078 | + goto out; |
---|
| 1079 | + |
---|
| 1080 | + ps->pinst = pinst; |
---|
| 1081 | + |
---|
| 1082 | + get_online_cpus(); |
---|
| 1083 | + pd = padata_alloc_pd(ps); |
---|
| 1084 | + put_online_cpus(); |
---|
| 1085 | + |
---|
| 1086 | + if (!pd) |
---|
| 1087 | + goto out_free_ps; |
---|
| 1088 | + |
---|
| 1089 | + mutex_lock(&pinst->lock); |
---|
| 1090 | + RCU_INIT_POINTER(ps->pd, pd); |
---|
| 1091 | + list_add(&ps->list, &pinst->pslist); |
---|
| 1092 | + mutex_unlock(&pinst->lock); |
---|
| 1093 | + |
---|
| 1094 | + return ps; |
---|
| 1095 | + |
---|
| 1096 | +out_free_ps: |
---|
| 1097 | + kfree(ps); |
---|
| 1098 | +out: |
---|
| 1099 | + return NULL; |
---|
| 1100 | +} |
---|
| 1101 | +EXPORT_SYMBOL(padata_alloc_shell); |
---|
| 1102 | + |
---|
| 1103 | +/** |
---|
| 1104 | + * padata_free_shell - free a padata shell |
---|
| 1105 | + * |
---|
| 1106 | + * @ps: padata shell to free |
---|
| 1107 | + */ |
---|
| 1108 | +void padata_free_shell(struct padata_shell *ps) |
---|
| 1109 | +{ |
---|
| 1110 | + if (!ps) |
---|
| 1111 | + return; |
---|
| 1112 | + |
---|
| 1113 | + mutex_lock(&ps->pinst->lock); |
---|
| 1114 | + list_del(&ps->list); |
---|
| 1115 | + padata_free_pd(rcu_dereference_protected(ps->pd, 1)); |
---|
| 1116 | + mutex_unlock(&ps->pinst->lock); |
---|
| 1117 | + |
---|
| 1118 | + kfree(ps); |
---|
| 1119 | +} |
---|
| 1120 | +EXPORT_SYMBOL(padata_free_shell); |
---|
| 1121 | + |
---|
| 1122 | +void __init padata_init(void) |
---|
| 1123 | +{ |
---|
| 1124 | + unsigned int i, possible_cpus; |
---|
| 1125 | +#ifdef CONFIG_HOTPLUG_CPU |
---|
1010 | 1126 | int ret; |
---|
1011 | 1127 | |
---|
1012 | 1128 | ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "padata:online", |
---|
1013 | | - padata_cpu_online, |
---|
1014 | | - padata_cpu_prep_down); |
---|
| 1129 | + padata_cpu_online, NULL); |
---|
1015 | 1130 | if (ret < 0) |
---|
1016 | | - return ret; |
---|
| 1131 | + goto err; |
---|
1017 | 1132 | hp_online = ret; |
---|
1018 | | - return 0; |
---|
1019 | | -} |
---|
1020 | | -module_init(padata_driver_init); |
---|
1021 | 1133 | |
---|
1022 | | -static __exit void padata_driver_exit(void) |
---|
1023 | | -{ |
---|
1024 | | - cpuhp_remove_multi_state(hp_online); |
---|
1025 | | -} |
---|
1026 | | -module_exit(padata_driver_exit); |
---|
| 1134 | + ret = cpuhp_setup_state_multi(CPUHP_PADATA_DEAD, "padata:dead", |
---|
| 1135 | + NULL, padata_cpu_dead); |
---|
| 1136 | + if (ret < 0) |
---|
| 1137 | + goto remove_online_state; |
---|
1027 | 1138 | #endif |
---|
| 1139 | + |
---|
| 1140 | + possible_cpus = num_possible_cpus(); |
---|
| 1141 | + padata_works = kmalloc_array(possible_cpus, sizeof(struct padata_work), |
---|
| 1142 | + GFP_KERNEL); |
---|
| 1143 | + if (!padata_works) |
---|
| 1144 | + goto remove_dead_state; |
---|
| 1145 | + |
---|
| 1146 | + for (i = 0; i < possible_cpus; ++i) |
---|
| 1147 | + list_add(&padata_works[i].pw_list, &padata_free_works); |
---|
| 1148 | + |
---|
| 1149 | + return; |
---|
| 1150 | + |
---|
| 1151 | +remove_dead_state: |
---|
| 1152 | +#ifdef CONFIG_HOTPLUG_CPU |
---|
| 1153 | + cpuhp_remove_multi_state(CPUHP_PADATA_DEAD); |
---|
| 1154 | +remove_online_state: |
---|
| 1155 | + cpuhp_remove_multi_state(hp_online); |
---|
| 1156 | +err: |
---|
| 1157 | +#endif |
---|
| 1158 | + pr_warn("padata: initialization failed\n"); |
---|
| 1159 | +} |
---|