view src/os/unix/ngx_sunpro_atomic_sparc64.h @ 7870:e169cce912c7 quic

Avoid retransmitting of packets with discarded keys. Sections 4.10.1 and 4.10.2 of quic transport describe discarding of initial and handshake keys. Since the keys are discarded, we no longer need to retransmit packets and corresponding queues should be emptied. This patch removes previously added workaround that did not require acknowledgement for initial packets, resulting in avoiding retransmission, which is wrong because a packet could be lost and we have to retransmit it.
author Vladimir Homutov <vl@nginx.com>
date Mon, 18 May 2020 13:54:53 +0300
parents d620f497c50f
children
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/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#if (NGX_PTR_SIZE == 4)
#define NGX_CASA  ngx_casa
#else
#define NGX_CASA  ngx_casxa
#endif


ngx_atomic_uint_t
ngx_casa(ngx_atomic_uint_t set, ngx_atomic_uint_t old, ngx_atomic_t *lock);

ngx_atomic_uint_t
ngx_casxa(ngx_atomic_uint_t set, ngx_atomic_uint_t old, ngx_atomic_t *lock);

/* the code in src/os/unix/ngx_sunpro_sparc64.il */


static ngx_inline ngx_atomic_uint_t
ngx_atomic_cmp_set(ngx_atomic_t *lock, ngx_atomic_uint_t old,
    ngx_atomic_uint_t set)
{
    set = NGX_CASA(set, old, lock);

    return (set == old);
}


static ngx_inline ngx_atomic_int_t
ngx_atomic_fetch_add(ngx_atomic_t *value, ngx_atomic_int_t add)
{
    ngx_atomic_uint_t  old, res;

    old = *value;

    for ( ;; ) {

        res = old + add;

        res = NGX_CASA(res, old, value);

        if (res == old) {
            return res;
        }

        old = res;
    }
}


#define ngx_memory_barrier()                                                  \
        __asm (".volatile");                                                  \
        __asm ("membar #LoadLoad | #LoadStore | #StoreStore | #StoreLoad");   \
        __asm (".nonvolatile")

#define ngx_cpu_pause()