diff options
Diffstat (limited to 'src/nxt_port_memory_int.h')
| -rw-r--r-- | src/nxt_port_memory_int.h | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/src/nxt_port_memory_int.h b/src/nxt_port_memory_int.h new file mode 100644 index 00000000..d82b6237 --- /dev/null +++ b/src/nxt_port_memory_int.h @@ -0,0 +1,179 @@ + +/* + * Copyright (C) Max Romanov + * Copyright (C) NGINX, Inc. + */ + +#ifndef _NXT_PORT_MEMORY_INT_H_INCLUDED_ +#define _NXT_PORT_MEMORY_INT_H_INCLUDED_ + + +#include <stdint.h> +#include <nxt_atomic.h> + + +#ifdef NXT_MMAP_TINY_CHUNK + +#define PORT_MMAP_CHUNK_SIZE 16 +#define PORT_MMAP_HEADER_SIZE 1024 +#define PORT_MMAP_DATA_SIZE 1024 + +#else + +#define PORT_MMAP_CHUNK_SIZE (1024 * 16) +#define PORT_MMAP_HEADER_SIZE (1024 * 4) +#define PORT_MMAP_DATA_SIZE (1024 * 1024 * 10) + +#endif + + +#define PORT_MMAP_SIZE (PORT_MMAP_HEADER_SIZE + PORT_MMAP_DATA_SIZE) +#define PORT_MMAP_CHUNK_COUNT (PORT_MMAP_DATA_SIZE / PORT_MMAP_CHUNK_SIZE) + + +typedef uint32_t nxt_chunk_id_t; + +typedef nxt_atomic_uint_t nxt_free_map_t; + +#define FREE_BITS (sizeof(nxt_free_map_t) * 8) + +#define FREE_IDX(nchunk) ((nchunk) / FREE_BITS) + +#define FREE_MASK(nchunk) \ + ( 1ULL << ( (nchunk) % FREE_BITS ) ) + +#define MAX_FREE_IDX FREE_IDX(PORT_MMAP_CHUNK_COUNT) + + +/* Mapped at the start of shared memory segment. */ +struct nxt_port_mmap_header_s { + uint32_t id; + nxt_pid_t pid; /* For sanity check. */ + nxt_free_map_t free_map[MAX_FREE_IDX]; +}; + + +/* + * Element of nxt_process_t.incoming/outgoing, shared memory segment + * descriptor. + */ +struct nxt_port_mmap_s { + nxt_port_mmap_header_t *hdr; +}; + +typedef struct nxt_port_mmap_msg_s nxt_port_mmap_msg_t; + +/* Passed as a second iov chunk when 'mmap' bit in nxt_port_msg_t is 1. */ +struct nxt_port_mmap_msg_s { + uint32_t mmap_id; /* Mmap index in nxt_process_t.outgoing. */ + nxt_chunk_id_t chunk_id; /* Mmap chunk index. */ + uint32_t size; /* Payload data size. */ +}; + + +static nxt_bool_t +nxt_port_mmap_get_free_chunk(nxt_port_mmap_header_t *hdr, nxt_chunk_id_t *c); + +#define nxt_port_mmap_get_chunk_busy(hdr, c) \ + ((hdr->free_map[FREE_IDX(c)] & FREE_MASK(c)) == 0) + +nxt_inline void +nxt_port_mmap_set_chunk_busy(nxt_port_mmap_header_t *hdr, nxt_chunk_id_t c); + +nxt_inline nxt_bool_t +nxt_port_mmap_chk_set_chunk_busy(nxt_port_mmap_header_t *hdr, nxt_chunk_id_t c); + +nxt_inline void +nxt_port_mmap_set_chunk_free(nxt_port_mmap_header_t *hdr, nxt_chunk_id_t c); + +nxt_inline nxt_chunk_id_t +nxt_port_mmap_chunk_id(nxt_port_mmap_header_t *hdr, u_char *p) +{ + u_char *mm_start; + + mm_start = (u_char *) hdr; + + return ((p - mm_start) - PORT_MMAP_HEADER_SIZE) / PORT_MMAP_CHUNK_SIZE; +} + + +nxt_inline u_char * +nxt_port_mmap_chunk_start(nxt_port_mmap_header_t *hdr, nxt_chunk_id_t c) +{ + u_char *mm_start; + + mm_start = (u_char *) hdr; + + return mm_start + PORT_MMAP_HEADER_SIZE + c * PORT_MMAP_CHUNK_SIZE; +} + + +static nxt_bool_t +nxt_port_mmap_get_free_chunk(nxt_port_mmap_header_t *hdr, nxt_chunk_id_t *c) +{ + int ffs; + size_t i; + nxt_chunk_id_t chunk; + nxt_free_map_t bits; + nxt_free_map_t *free_map; + + free_map = hdr->free_map; + + for (i = 0; i < MAX_FREE_IDX; i++) { + bits = free_map[i]; + if (bits == 0) { + continue; + } + + ffs = __builtin_ffsll(bits); + if (ffs != 0) { + chunk = i * FREE_BITS + ffs - 1; + + if (nxt_port_mmap_chk_set_chunk_busy(hdr, chunk)) { + *c = chunk; + return 1; + } + } + } + + return 0; +} + + +nxt_inline void +nxt_port_mmap_set_chunk_busy(nxt_port_mmap_header_t *hdr, nxt_chunk_id_t c) +{ + nxt_atomic_and_fetch(hdr->free_map + FREE_IDX(c), ~FREE_MASK(c)); +} + + +nxt_inline nxt_bool_t +nxt_port_mmap_chk_set_chunk_busy(nxt_port_mmap_header_t *hdr, nxt_chunk_id_t c) +{ + nxt_free_map_t *f; + nxt_free_map_t free_val, busy_val; + + f = hdr->free_map + FREE_IDX(c); + + while ( (*f & FREE_MASK(c)) != 0 ) { + + free_val = *f | FREE_MASK(c); + busy_val = free_val & ~FREE_MASK(c); + + if (nxt_atomic_cmp_set(f, free_val, busy_val) != 0) { + return 1; + } + } + + return 0; +} + + +nxt_inline void +nxt_port_mmap_set_chunk_free(nxt_port_mmap_header_t *hdr, nxt_chunk_id_t c) +{ + nxt_atomic_or_fetch(hdr->free_map + FREE_IDX(c), FREE_MASK(c)); +} + + +#endif /* _NXT_PORT_MEMORY_INT_H_INCLUDED_ */ |