view src/core/ngx_spinlock.c @ 7713:e9891e8ee975 quic

Configurable transport parameters. - integer parameters can be configured using the following directives: quic_max_idle_timeout quic_max_ack_delay quic_max_packet_size quic_initial_max_data quic_initial_max_stream_data_bidi_local quic_initial_max_stream_data_bidi_remote quic_initial_max_stream_data_uni quic_initial_max_streams_bidi quic_initial_max_streams_uni quic_ack_delay_exponent quic_active_migration quic_active_connection_id_limit - only following parameters are actually sent: active_connection_id_limit initial_max_streams_uni initial_max_streams_bidi initial_max_stream_data_bidi_local initial_max_stream_data_bidi_remote initial_max_stream_data_uni (other parameters are to be added into ngx_quic_create_transport_params() function as needed, should be easy now) - draft 24 and draft 27 are now supported (at compile-time using quic_version macro)
author Vladimir Homutov <vl@nginx.com>
date Fri, 20 Mar 2020 13:47:44 +0300
parents f737e406aa68
children
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/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#include <ngx_config.h>
#include <ngx_core.h>


void
ngx_spinlock(ngx_atomic_t *lock, ngx_atomic_int_t value, ngx_uint_t spin)
{

#if (NGX_HAVE_ATOMIC_OPS)

    ngx_uint_t  i, n;

    for ( ;; ) {

        if (*lock == 0 && ngx_atomic_cmp_set(lock, 0, value)) {
            return;
        }

        if (ngx_ncpu > 1) {

            for (n = 1; n < spin; n <<= 1) {

                for (i = 0; i < n; i++) {
                    ngx_cpu_pause();
                }

                if (*lock == 0 && ngx_atomic_cmp_set(lock, 0, value)) {
                    return;
                }
            }
        }

        ngx_sched_yield();
    }

#else

#if (NGX_THREADS)

#error ngx_spinlock() or ngx_atomic_cmp_set() are not defined !

#endif

#endif

}