MEDIUM: ring/applet: turn the wait_entry list to an mt_list instead

Rings are keeping a lock only for the list, which apparently doesn't
need anything more than an mt_list, so let's first turn it into that
before dropping the lock. There should be no visible effect.
This commit is contained in:
Willy Tarreau 2024-02-28 17:04:40 +01:00
parent 04f1e3f3d9
commit a2d2dbf210
8 changed files with 28 additions and 24 deletions

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@ -97,7 +97,7 @@ struct appctx {
struct buffer_wait buffer_wait; /* position in the list of objects waiting for a buffer */ struct buffer_wait buffer_wait; /* position in the list of objects waiting for a buffer */
struct task *t; /* task associated to the applet */ struct task *t; /* task associated to the applet */
struct freq_ctr call_rate; /* appctx call rate */ struct freq_ctr call_rate; /* appctx call rate */
struct list wait_entry; /* entry in a list of waiters for an event (e.g. ring events) */ struct mt_list wait_entry; /* entry in a list of waiters for an event (e.g. ring events) */
/* The pointer seen by application code is appctx->svcctx. In 2.7 the /* The pointer seen by application code is appctx->svcctx. In 2.7 the
* anonymous union and the "ctx" struct disappeared, and the struct * anonymous union and the "ctx" struct disappeared, and the struct

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@ -95,7 +95,7 @@
struct dns_ring { struct dns_ring {
struct buffer buf; // storage area struct buffer buf; // storage area
struct list waiters; // list of waiters, for now, CLI "show event" struct mt_list waiters; // list of waiters, for now, CLI "show event"
__decl_thread(HA_RWLOCK_T lock); __decl_thread(HA_RWLOCK_T lock);
int readers_count; int readers_count;
}; };

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@ -121,7 +121,7 @@ struct ring_storage {
/* this is the ring definition, config, waiters etc */ /* this is the ring definition, config, waiters etc */
struct ring { struct ring {
struct ring_storage *storage; // the mapped part struct ring_storage *storage; // the mapped part
struct list waiters; // list of waiters, for now, CLI "show event" struct mt_list waiters; // list of waiters, for now, CLI "show event"
__decl_thread(HA_RWLOCK_T lock); __decl_thread(HA_RWLOCK_T lock);
int readers_count; int readers_count;
uint flags; // RING_FL_* uint flags; // RING_FL_*

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@ -239,7 +239,7 @@ struct appctx *appctx_new_on(struct applet *applet, struct sedesc *sedesc, int t
goto fail_appctx; goto fail_appctx;
} }
LIST_INIT(&appctx->wait_entry); MT_LIST_INIT(&appctx->wait_entry);
appctx->obj_type = OBJ_TYPE_APPCTX; appctx->obj_type = OBJ_TYPE_APPCTX;
appctx->applet = applet; appctx->applet = applet;
appctx->sess = NULL; appctx->sess = NULL;

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@ -471,7 +471,7 @@ static void dns_session_io_handler(struct appctx *appctx)
} }
HA_RWLOCK_WRLOCK(DNS_LOCK, &ring->lock); HA_RWLOCK_WRLOCK(DNS_LOCK, &ring->lock);
LIST_DEL_INIT(&appctx->wait_entry); MT_LIST_DELETE(&appctx->wait_entry);
HA_RWLOCK_WRUNLOCK(DNS_LOCK, &ring->lock); HA_RWLOCK_WRUNLOCK(DNS_LOCK, &ring->lock);
HA_RWLOCK_RDLOCK(DNS_LOCK, &ring->lock); HA_RWLOCK_RDLOCK(DNS_LOCK, &ring->lock);
@ -633,8 +633,8 @@ static void dns_session_io_handler(struct appctx *appctx)
if (ret) { if (ret) {
/* let's be woken up once new request to write arrived */ /* let's be woken up once new request to write arrived */
HA_RWLOCK_WRLOCK(DNS_LOCK, &ring->lock); HA_RWLOCK_WRLOCK(DNS_LOCK, &ring->lock);
BUG_ON(LIST_INLIST(&appctx->wait_entry)); BUG_ON(MT_LIST_INLIST(&appctx->wait_entry));
LIST_APPEND(&ring->waiters, &appctx->wait_entry); MT_LIST_APPEND(&ring->waiters, &appctx->wait_entry);
HA_RWLOCK_WRUNLOCK(DNS_LOCK, &ring->lock); HA_RWLOCK_WRUNLOCK(DNS_LOCK, &ring->lock);
applet_have_no_more_data(appctx); applet_have_no_more_data(appctx);
} }
@ -797,7 +797,7 @@ void dns_session_free(struct dns_session *ds)
BUG_ON(!LIST_ISEMPTY(&ds->list)); BUG_ON(!LIST_ISEMPTY(&ds->list));
BUG_ON(!LIST_ISEMPTY(&ds->waiter)); BUG_ON(!LIST_ISEMPTY(&ds->waiter));
BUG_ON(!LIST_ISEMPTY(&ds->queries)); BUG_ON(!LIST_ISEMPTY(&ds->queries));
BUG_ON(!LIST_ISEMPTY(&ds->ring.waiters)); BUG_ON(!MT_LIST_ISEMPTY(&ds->ring.waiters));
BUG_ON(!eb_is_empty(&ds->query_ids)); BUG_ON(!eb_is_empty(&ds->query_ids));
pool_free(dns_session_pool, ds); pool_free(dns_session_pool, ds);
} }
@ -849,7 +849,7 @@ static void dns_session_release(struct appctx *appctx)
* to retry a conn with a different appctx. * to retry a conn with a different appctx.
*/ */
HA_RWLOCK_WRLOCK(DNS_LOCK, &ds->ring.lock); HA_RWLOCK_WRLOCK(DNS_LOCK, &ds->ring.lock);
LIST_DEL_INIT(&appctx->wait_entry); MT_LIST_DELETE(&appctx->wait_entry);
HA_RWLOCK_WRUNLOCK(DNS_LOCK, &ds->ring.lock); HA_RWLOCK_WRUNLOCK(DNS_LOCK, &ds->ring.lock);
dss = ds->dss; dss = ds->dss;

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@ -34,7 +34,7 @@
void dns_ring_init(struct dns_ring *ring, void *area, size_t size) void dns_ring_init(struct dns_ring *ring, void *area, size_t size)
{ {
HA_RWLOCK_INIT(&ring->lock); HA_RWLOCK_INIT(&ring->lock);
LIST_INIT(&ring->waiters); MT_LIST_INIT(&ring->waiters);
ring->readers_count = 0; ring->readers_count = 0;
ring->buf = b_make(area, size, 0, 0); ring->buf = b_make(area, size, 0, 0);
/* write the initial RC byte */ /* write the initial RC byte */
@ -94,6 +94,7 @@ ssize_t dns_ring_write(struct dns_ring *ring, size_t maxlen, const struct ist pf
size_t lenlen; size_t lenlen;
uint64_t dellen; uint64_t dellen;
int dellenlen; int dellenlen;
struct mt_list *elt1, elt2;
ssize_t sent = 0; ssize_t sent = 0;
int i; int i;
@ -165,7 +166,7 @@ ssize_t dns_ring_write(struct dns_ring *ring, size_t maxlen, const struct ist pf
sent = lenlen + totlen + 1; sent = lenlen + totlen + 1;
/* notify potential readers */ /* notify potential readers */
list_for_each_entry(appctx, &ring->waiters, wait_entry) mt_list_for_each_entry_safe(appctx, &ring->waiters, wait_entry, elt1, elt2)
appctx_wakeup(appctx); appctx_wakeup(appctx);
done_buf: done_buf:
@ -209,7 +210,7 @@ void dns_ring_detach_appctx(struct dns_ring *ring, struct appctx *appctx, size_t
ofs -= b_head_ofs(&ring->buf); ofs -= b_head_ofs(&ring->buf);
BUG_ON(ofs >= b_size(&ring->buf)); BUG_ON(ofs >= b_size(&ring->buf));
LIST_DEL_INIT(&appctx->wait_entry); MT_LIST_DELETE(&appctx->wait_entry);
HA_ATOMIC_DEC(b_peek(&ring->buf, ofs)); HA_ATOMIC_DEC(b_peek(&ring->buf, ofs));
} }
HA_ATOMIC_DEC(&ring->readers_count); HA_ATOMIC_DEC(&ring->readers_count);

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@ -46,7 +46,7 @@ struct show_ring_ctx {
void ring_init(struct ring *ring, void *area, size_t size, int reset) void ring_init(struct ring *ring, void *area, size_t size, int reset)
{ {
HA_RWLOCK_INIT(&ring->lock); HA_RWLOCK_INIT(&ring->lock);
LIST_INIT(&ring->waiters); MT_LIST_INIT(&ring->waiters);
ring->readers_count = 0; ring->readers_count = 0;
ring->flags = 0; ring->flags = 0;
ring->storage = area; ring->storage = area;
@ -176,7 +176,6 @@ ssize_t ring_write(struct ring *ring, size_t maxlen, const struct ist pfx[], siz
size_t ring_size; size_t ring_size;
char *ring_area; char *ring_area;
struct ist v1, v2; struct ist v1, v2;
struct appctx *appctx;
size_t msglen = 0; size_t msglen = 0;
size_t lenlen; size_t lenlen;
size_t needed; size_t needed;
@ -340,8 +339,11 @@ ssize_t ring_write(struct ring *ring, size_t maxlen, const struct ist pfx[], siz
/* notify potential readers */ /* notify potential readers */
if (sent && HA_ATOMIC_LOAD(&ring->readers_count)) { if (sent && HA_ATOMIC_LOAD(&ring->readers_count)) {
struct mt_list *elt1, elt2;
struct appctx *appctx;
HA_RWLOCK_RDLOCK(RING_LOCK, &ring->lock); HA_RWLOCK_RDLOCK(RING_LOCK, &ring->lock);
list_for_each_entry(appctx, &ring->waiters, wait_entry) mt_list_for_each_entry_safe(appctx, &ring->waiters, wait_entry, elt1, elt2)
appctx_wakeup(appctx); appctx_wakeup(appctx);
HA_RWLOCK_RDUNLOCK(RING_LOCK, &ring->lock); HA_RWLOCK_RDUNLOCK(RING_LOCK, &ring->lock);
} }
@ -378,13 +380,15 @@ void ring_detach_appctx(struct ring *ring, struct appctx *appctx, size_t ofs)
return; return;
HA_RWLOCK_WRLOCK(RING_LOCK, &ring->lock); HA_RWLOCK_WRLOCK(RING_LOCK, &ring->lock);
HA_ATOMIC_DEC(&ring->readers_count);
if (ofs != ~0) { if (ofs != ~0) {
/* reader was still attached */ /* reader was still attached */
uint8_t *area = (uint8_t *)ring_area(ring); uint8_t *area = (uint8_t *)ring_area(ring);
uint8_t readers; uint8_t readers;
BUG_ON(ofs >= ring_size(ring)); BUG_ON(ofs >= ring_size(ring));
LIST_DEL_INIT(&appctx->wait_entry); MT_LIST_DELETE(&appctx->wait_entry);
/* dec readers count */ /* dec readers count */
do { do {
@ -392,7 +396,6 @@ void ring_detach_appctx(struct ring *ring, struct appctx *appctx, size_t ofs)
} while ((readers > RING_MAX_READERS || } while ((readers > RING_MAX_READERS ||
!_HA_ATOMIC_CAS(area + ofs, &readers, readers - 1)) && __ha_cpu_relax()); !_HA_ATOMIC_CAS(area + ofs, &readers, readers - 1)) && __ha_cpu_relax());
} }
HA_ATOMIC_DEC(&ring->readers_count);
HA_RWLOCK_WRUNLOCK(RING_LOCK, &ring->lock); HA_RWLOCK_WRUNLOCK(RING_LOCK, &ring->lock);
} }
@ -564,7 +567,7 @@ int cli_io_handler_show_ring(struct appctx *appctx)
return 1; return 1;
HA_RWLOCK_WRLOCK(RING_LOCK, &ring->lock); HA_RWLOCK_WRLOCK(RING_LOCK, &ring->lock);
LIST_DEL_INIT(&appctx->wait_entry); MT_LIST_DELETE(&appctx->wait_entry);
HA_RWLOCK_WRUNLOCK(RING_LOCK, &ring->lock); HA_RWLOCK_WRUNLOCK(RING_LOCK, &ring->lock);
ret = ring_dispatch_messages(ring, appctx, &ctx->ofs, &last_ofs, ctx->flags, applet_append_line); ret = ring_dispatch_messages(ring, appctx, &ctx->ofs, &last_ofs, ctx->flags, applet_append_line);
@ -576,7 +579,7 @@ int cli_io_handler_show_ring(struct appctx *appctx)
if (!sc_oc(sc)->output && !(sc->flags & SC_FL_SHUT_DONE)) { if (!sc_oc(sc)->output && !(sc->flags & SC_FL_SHUT_DONE)) {
/* let's be woken up once new data arrive */ /* let's be woken up once new data arrive */
HA_RWLOCK_WRLOCK(RING_LOCK, &ring->lock); HA_RWLOCK_WRLOCK(RING_LOCK, &ring->lock);
LIST_APPEND(&ring->waiters, &appctx->wait_entry); MT_LIST_APPEND(&ring->waiters, &appctx->wait_entry);
ofs = ring_tail(ring); ofs = ring_tail(ring);
HA_RWLOCK_WRUNLOCK(RING_LOCK, &ring->lock); HA_RWLOCK_WRUNLOCK(RING_LOCK, &ring->lock);
if (ofs != last_ofs) { if (ofs != last_ofs) {

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@ -383,7 +383,7 @@ static void sink_forward_io_handler(struct appctx *appctx)
} }
HA_RWLOCK_WRLOCK(RING_LOCK, &ring->lock); HA_RWLOCK_WRLOCK(RING_LOCK, &ring->lock);
LIST_DEL_INIT(&appctx->wait_entry); MT_LIST_DELETE(&appctx->wait_entry);
HA_RWLOCK_WRUNLOCK(RING_LOCK, &ring->lock); HA_RWLOCK_WRUNLOCK(RING_LOCK, &ring->lock);
ret = ring_dispatch_messages(ring, appctx, &sft->ofs, &last_ofs, 0, applet_append_line); ret = ring_dispatch_messages(ring, appctx, &sft->ofs, &last_ofs, 0, applet_append_line);
@ -391,7 +391,7 @@ static void sink_forward_io_handler(struct appctx *appctx)
if (ret) { if (ret) {
/* let's be woken up once new data arrive */ /* let's be woken up once new data arrive */
HA_RWLOCK_WRLOCK(RING_LOCK, &ring->lock); HA_RWLOCK_WRLOCK(RING_LOCK, &ring->lock);
LIST_APPEND(&ring->waiters, &appctx->wait_entry); MT_LIST_APPEND(&ring->waiters, &appctx->wait_entry);
ofs = ring_tail(ring); ofs = ring_tail(ring);
HA_RWLOCK_WRUNLOCK(RING_LOCK, &ring->lock); HA_RWLOCK_WRUNLOCK(RING_LOCK, &ring->lock);
if (ofs != last_ofs) { if (ofs != last_ofs) {
@ -452,14 +452,14 @@ static void sink_forward_oc_io_handler(struct appctx *appctx)
} }
HA_RWLOCK_WRLOCK(RING_LOCK, &ring->lock); HA_RWLOCK_WRLOCK(RING_LOCK, &ring->lock);
LIST_DEL_INIT(&appctx->wait_entry); MT_LIST_DELETE(&appctx->wait_entry);
HA_RWLOCK_WRUNLOCK(RING_LOCK, &ring->lock); HA_RWLOCK_WRUNLOCK(RING_LOCK, &ring->lock);
ret = ring_dispatch_messages(ring, appctx, &sft->ofs, &last_ofs, 0, syslog_applet_append_event); ret = ring_dispatch_messages(ring, appctx, &sft->ofs, &last_ofs, 0, syslog_applet_append_event);
if (ret) { if (ret) {
/* let's be woken up once new data arrive */ /* let's be woken up once new data arrive */
HA_RWLOCK_WRLOCK(RING_LOCK, &ring->lock); HA_RWLOCK_WRLOCK(RING_LOCK, &ring->lock);
LIST_APPEND(&ring->waiters, &appctx->wait_entry); MT_LIST_APPEND(&ring->waiters, &appctx->wait_entry);
ofs = ring_tail(ring); ofs = ring_tail(ring);
HA_RWLOCK_WRUNLOCK(RING_LOCK, &ring->lock); HA_RWLOCK_WRUNLOCK(RING_LOCK, &ring->lock);
if (ofs != last_ofs) { if (ofs != last_ofs) {
@ -492,7 +492,7 @@ void __sink_forward_session_deinit(struct sink_forward_target *sft)
return; return;
HA_RWLOCK_WRLOCK(RING_LOCK, &sink->ctx.ring->lock); HA_RWLOCK_WRLOCK(RING_LOCK, &sink->ctx.ring->lock);
LIST_DEL_INIT(&sft->appctx->wait_entry); MT_LIST_DELETE(&sft->appctx->wait_entry);
HA_RWLOCK_WRUNLOCK(RING_LOCK, &sink->ctx.ring->lock); HA_RWLOCK_WRUNLOCK(RING_LOCK, &sink->ctx.ring->lock);
sft->appctx = NULL; sft->appctx = NULL;