tools/virtio/ringtest/ptr_ring.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #define _GNU_SOURCE
   3 #include "main.h"
   4 #include <stdlib.h>
   5 #include <stdio.h>
   6 #include <string.h>
   7 #include <pthread.h>
   8 #include <malloc.h>
   9 #include <assert.h>
  10 #include <errno.h>
  11 #include <limits.h>
  12
  13 #define SMP_CACHE_BYTES 64
  14 #define cache_line_size() SMP_CACHE_BYTES
  15 #define ____cacheline_aligned_in_smp __attribute__ ((aligned (SMP_CACHE_BYTES)))
  16 #define unlikely(x)    (__builtin_expect(!!(x), 0))
  17 #define likely(x)    (__builtin_expect(!!(x), 1))
  18 #define ALIGN(x, a) (((x) + (a) - 1) / (a) * (a))
  19 #define SIZE_MAX        (~(size_t)0)
  20 #define KMALLOC_MAX_SIZE SIZE_MAX
  21
  22 typedef pthread_spinlock_t  spinlock_t;
  23
  24 typedef int gfp_t;
  25 #define __GFP_ZERO 0x1
  26
  27 static void *kmalloc(unsigned size, gfp_t gfp)
  28 {
  29         void *p = memalign(64, size);
  30         if (!p)
  31                 return p;
  32
  33         if (gfp & __GFP_ZERO)
  34                 memset(p, 0, size);
  35         return p;
  36 }
  37
  38 static inline void *kzalloc(unsigned size, gfp_t flags)
  39 {
  40         return kmalloc(size, flags | __GFP_ZERO);
  41 }
  42
  43 static inline void *kmalloc_array(size_t n, size_t size, gfp_t flags)
  44 {
  45         if (size != 0 && n > SIZE_MAX / size)
  46                 return NULL;
  47         return kmalloc(n * size, flags);
  48 }
  49
  50 static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
  51 {
  52         return kmalloc_array(n, size, flags | __GFP_ZERO);
  53 }
  54
  55 static void kfree(void *p)
  56 {
  57         if (p)
  58                 free(p);
  59 }
  60
  61 #define kvmalloc_array kmalloc_array
  62 #define kvfree kfree
  63
  64 static void spin_lock_init(spinlock_t *lock)
  65 {
  66         int r = pthread_spin_init(lock, 0);
  67         assert(!r);
  68 }
  69
  70 static void spin_lock(spinlock_t *lock)
  71 {
  72         int ret = pthread_spin_lock(lock);
  73         assert(!ret);
  74 }
  75
  76 static void spin_unlock(spinlock_t *lock)
  77 {
  78         int ret = pthread_spin_unlock(lock);
  79         assert(!ret);
  80 }
  81
  82 static void spin_lock_bh(spinlock_t *lock)
  83 {
  84         spin_lock(lock);
  85 }
  86
  87 static void spin_unlock_bh(spinlock_t *lock)
  88 {
  89         spin_unlock(lock);
  90 }
  91
  92 static void spin_lock_irq(spinlock_t *lock)
  93 {
  94         spin_lock(lock);
  95 }
  96
  97 static void spin_unlock_irq(spinlock_t *lock)
  98 {
  99         spin_unlock(lock);
 100 }
 101
 102 static void spin_lock_irqsave(spinlock_t *lock, unsigned long f)
 103 {
 104         spin_lock(lock);
 105 }
 106
 107 static void spin_unlock_irqrestore(spinlock_t *lock, unsigned long f)
 108 {
 109         spin_unlock(lock);
 110 }
 111
 112 #include "../../../include/linux/ptr_ring.h"
 113
 114 static unsigned long long headcnt, tailcnt;
 115 static struct ptr_ring array ____cacheline_aligned_in_smp;
 116
 117 /* implemented by ring */
 118 void alloc_ring(void)
 119 {
 120         int ret = ptr_ring_init(&array, ring_size, 0);
 121         assert(!ret);
 122         /* Hacky way to poke at ring internals. Useful for testing though. */
 123         if (param)
 124                 array.batch = param;
 125 }
 126
 127 /* guest side */
 128 int add_inbuf(unsigned len, void *buf, void *datap)
 129 {
 130         int ret;
 131
 132         ret = __ptr_ring_produce(&array, buf);
 133         if (ret >= 0) {
 134                 ret = 0;
 135                 headcnt++;
 136         }
 137
 138         return ret;
 139 }
 140
 141 /*
 142  * ptr_ring API provides no way for producer to find out whether a given
 143  * buffer was consumed.  Our tests merely require that a successful get_buf
 144  * implies that add_inbuf succeed in the past, and that add_inbuf will succeed,
 145  * fake it accordingly.
 146  */
 147 void *get_buf(unsigned *lenp, void **bufp)
 148 {
 149         void *datap;
 150
 151         if (tailcnt == headcnt || __ptr_ring_full(&array))
 152                 datap = NULL;
 153         else {
 154                 datap = "Buffer\n";
 155                 ++tailcnt;
 156         }
 157
 158         return datap;
 159 }
 160
 161 bool used_empty()
 162 {
 163         return (tailcnt == headcnt || __ptr_ring_full(&array));
 164 }
 165
 166 void disable_call()
 167 {
 168         assert(0);
 169 }
 170
 171 bool enable_call()
 172 {
 173         assert(0);
 174 }
 175
 176 void kick_available(void)
 177 {
 178         assert(0);
 179 }
 180
 181 /* host side */
 182 void disable_kick()
 183 {
 184         assert(0);
 185 }
 186
 187 bool enable_kick()
 188 {
 189         assert(0);
 190 }
 191
 192 bool avail_empty()
 193 {
 194         return __ptr_ring_empty(&array);
 195 }
 196
 197 bool use_buf(unsigned *lenp, void **bufp)
 198 {
 199         void *ptr;
 200
 201         ptr = __ptr_ring_consume(&array);
 202
 203         return ptr;
 204 }
 205
 206 void call_used(void)
 207 {
 208         assert(0);
 209 }