diff options
Diffstat (limited to 'modules/http2/h2_mplx.c')
| -rw-r--r-- | modules/http2/h2_mplx.c | 1191 |
1 files changed, 1191 insertions, 0 deletions
diff --git a/modules/http2/h2_mplx.c b/modules/http2/h2_mplx.c new file mode 100644 index 0000000..99c47ea --- /dev/null +++ b/modules/http2/h2_mplx.c @@ -0,0 +1,1191 @@ +/* Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include <assert.h> +#include <stddef.h> +#include <stdlib.h> + +#include <apr_atomic.h> +#include <apr_thread_mutex.h> +#include <apr_thread_cond.h> +#include <apr_strings.h> +#include <apr_time.h> + +#include <httpd.h> +#include <http_core.h> +#include <http_connection.h> +#include <http_log.h> +#include <http_protocol.h> + +#include <mpm_common.h> + +#include "mod_http2.h" + +#include "h2.h" +#include "h2_private.h" +#include "h2_bucket_beam.h" +#include "h2_config.h" +#include "h2_c1.h" +#include "h2_conn_ctx.h" +#include "h2_protocol.h" +#include "h2_mplx.h" +#include "h2_request.h" +#include "h2_stream.h" +#include "h2_session.h" +#include "h2_c2.h" +#include "h2_workers.h" +#include "h2_util.h" + + +/* utility for iterating over ihash stream sets */ +typedef struct { + h2_mplx *m; + h2_stream *stream; + apr_time_t now; + apr_size_t count; +} stream_iter_ctx; + +static conn_rec *c2_prod_next(void *baton, int *phas_more); +static void c2_prod_done(void *baton, conn_rec *c2); +static void workers_shutdown(void *baton, int graceful); + +static void s_mplx_be_happy(h2_mplx *m, conn_rec *c, h2_conn_ctx_t *conn_ctx); +static void m_be_annoyed(h2_mplx *m); + +static apr_status_t mplx_pollset_create(h2_mplx *m); +static apr_status_t mplx_pollset_poll(h2_mplx *m, apr_interval_time_t timeout, + stream_ev_callback *on_stream_input, + stream_ev_callback *on_stream_output, + void *on_ctx); + +static apr_pool_t *pchild; + +/* APR callback invoked if allocation fails. */ +static int abort_on_oom(int retcode) +{ + ap_abort_on_oom(); + return retcode; /* unreachable, hopefully. */ +} + +apr_status_t h2_mplx_c1_child_init(apr_pool_t *pool, server_rec *s) +{ + pchild = pool; + return APR_SUCCESS; +} + +#define H2_MPLX_ENTER(m) \ + do { apr_status_t rv_lock; if ((rv_lock = apr_thread_mutex_lock(m->lock)) != APR_SUCCESS) {\ + return rv_lock;\ + } } while(0) + +#define H2_MPLX_LEAVE(m) \ + apr_thread_mutex_unlock(m->lock) + +#define H2_MPLX_ENTER_ALWAYS(m) \ + apr_thread_mutex_lock(m->lock) + +#define H2_MPLX_ENTER_MAYBE(m, dolock) \ + if (dolock) apr_thread_mutex_lock(m->lock) + +#define H2_MPLX_LEAVE_MAYBE(m, dolock) \ + if (dolock) apr_thread_mutex_unlock(m->lock) + +static void c1_input_consumed(void *ctx, h2_bucket_beam *beam, apr_off_t length) +{ + h2_stream_in_consumed(ctx, length); +} + +static int stream_is_running(h2_stream *stream) +{ + h2_conn_ctx_t *conn_ctx = h2_conn_ctx_get(stream->c2); + return conn_ctx && apr_atomic_read32(&conn_ctx->started) != 0 + && apr_atomic_read32(&conn_ctx->done) == 0; +} + +int h2_mplx_c1_stream_is_running(h2_mplx *m, h2_stream *stream) +{ + int rv; + + H2_MPLX_ENTER(m); + rv = stream_is_running(stream); + H2_MPLX_LEAVE(m); + return rv; +} + +static void c1c2_stream_joined(h2_mplx *m, h2_stream *stream) +{ + ap_assert(!stream_is_running(stream)); + + h2_ihash_remove(m->shold, stream->id); + APR_ARRAY_PUSH(m->spurge, h2_stream *) = stream; +} + +static void m_stream_cleanup(h2_mplx *m, h2_stream *stream) +{ + h2_conn_ctx_t *c2_ctx = h2_conn_ctx_get(stream->c2); + + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, m->c1, + H2_STRM_MSG(stream, "cleanup, unsubscribing from beam events")); + if (c2_ctx) { + if (c2_ctx->beam_out) { + h2_beam_on_was_empty(c2_ctx->beam_out, NULL, NULL); + } + if (c2_ctx->beam_in) { + h2_beam_on_send(c2_ctx->beam_in, NULL, NULL); + h2_beam_on_received(c2_ctx->beam_in, NULL, NULL); + h2_beam_on_consumed(c2_ctx->beam_in, NULL, NULL); + } + } + + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, m->c1, + H2_STRM_MSG(stream, "cleanup, removing from registries")); + ap_assert(stream->state == H2_SS_CLEANUP); + h2_stream_cleanup(stream); + h2_ihash_remove(m->streams, stream->id); + h2_iq_remove(m->q, stream->id); + + if (c2_ctx) { + if (!stream_is_running(stream)) { + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, m->c1, + H2_STRM_MSG(stream, "cleanup, c2 is done, move to spurge")); + /* processing has finished */ + APR_ARRAY_PUSH(m->spurge, h2_stream *) = stream; + } + else { + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, m->c1, + H2_STRM_MSG(stream, "cleanup, c2 is running, abort")); + /* c2 is still running */ + h2_c2_abort(stream->c2, m->c1); + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, m->c1, + H2_STRM_MSG(stream, "cleanup, c2 is done, move to shold")); + h2_ihash_add(m->shold, stream); + } + } + else { + /* never started */ + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, m->c1, + H2_STRM_MSG(stream, "cleanup, never started, move to spurge")); + APR_ARRAY_PUSH(m->spurge, h2_stream *) = stream; + } +} + +static h2_c2_transit *c2_transit_create(h2_mplx *m) +{ + apr_allocator_t *allocator; + apr_pool_t *ptrans; + h2_c2_transit *transit; + apr_status_t rv; + + /* We create a pool with its own allocator to be used for + * processing a request. This is the only way to have the processing + * independent of its parent pool in the sense that it can work in + * another thread. + */ + + rv = apr_allocator_create(&allocator); + if (rv == APR_SUCCESS) { + apr_allocator_max_free_set(allocator, ap_max_mem_free); + rv = apr_pool_create_ex(&ptrans, m->pool, NULL, allocator); + } + if (rv != APR_SUCCESS) { + /* maybe the log goes through, maybe not. */ + ap_log_cerror(APLOG_MARK, APLOG_ERR, rv, m->c1, + APLOGNO(10004) "h2_mplx: create transit pool"); + ap_abort_on_oom(); + return NULL; /* should never be reached. */ + } + + apr_allocator_owner_set(allocator, ptrans); + apr_pool_abort_set(abort_on_oom, ptrans); + apr_pool_tag(ptrans, "h2_c2_transit"); + + transit = apr_pcalloc(ptrans, sizeof(*transit)); + transit->pool = ptrans; + transit->bucket_alloc = apr_bucket_alloc_create(ptrans); + return transit; +} + +static void c2_transit_destroy(h2_c2_transit *transit) +{ + apr_pool_destroy(transit->pool); +} + +static h2_c2_transit *c2_transit_get(h2_mplx *m) +{ + h2_c2_transit **ptransit = apr_array_pop(m->c2_transits); + if (ptransit) { + return *ptransit; + } + return c2_transit_create(m); +} + +static void c2_transit_recycle(h2_mplx *m, h2_c2_transit *transit) +{ + if (m->c2_transits->nelts >= APR_INT32_MAX || + (apr_uint32_t)m->c2_transits->nelts >= m->max_spare_transits) { + c2_transit_destroy(transit); + } + else { + APR_ARRAY_PUSH(m->c2_transits, h2_c2_transit*) = transit; + } +} + +/** + * A h2_mplx needs to be thread-safe *and* if will be called by + * the h2_session thread *and* the h2_worker threads. Therefore: + * - calls are protected by a mutex lock, m->lock + * - the pool needs its own allocator, since apr_allocator_t are + * not re-entrant. The separate allocator works without a + * separate lock since we already protect h2_mplx itself. + * Since HTTP/2 connections can be expected to live longer than + * their HTTP/1 cousins, the separate allocator seems to work better + * than protecting a shared h2_session one with an own lock. + */ +h2_mplx *h2_mplx_c1_create(int child_num, apr_uint32_t id, h2_stream *stream0, + server_rec *s, apr_pool_t *parent, + h2_workers *workers) +{ + h2_conn_ctx_t *conn_ctx; + apr_status_t status = APR_SUCCESS; + apr_allocator_t *allocator; + apr_thread_mutex_t *mutex = NULL; + h2_mplx *m = NULL; + + m = apr_pcalloc(parent, sizeof(h2_mplx)); + m->stream0 = stream0; + m->c1 = stream0->c2; + m->s = s; + m->child_num = child_num; + m->id = id; + + /* We create a pool with its own allocator to be used for + * processing secondary connections. This is the only way to have the + * processing independent of its parent pool in the sense that it + * can work in another thread. Also, the new allocator needs its own + * mutex to synchronize sub-pools. + */ + status = apr_allocator_create(&allocator); + if (status != APR_SUCCESS) { + allocator = NULL; + goto failure; + } + + apr_allocator_max_free_set(allocator, ap_max_mem_free); + apr_pool_create_ex(&m->pool, parent, NULL, allocator); + if (!m->pool) goto failure; + + apr_pool_tag(m->pool, "h2_mplx"); + apr_allocator_owner_set(allocator, m->pool); + + status = apr_thread_mutex_create(&mutex, APR_THREAD_MUTEX_DEFAULT, + m->pool); + if (APR_SUCCESS != status) goto failure; + apr_allocator_mutex_set(allocator, mutex); + + status = apr_thread_mutex_create(&m->lock, APR_THREAD_MUTEX_DEFAULT, + m->pool); + if (APR_SUCCESS != status) goto failure; + + m->max_streams = h2_config_sgeti(s, H2_CONF_MAX_STREAMS); + m->stream_max_mem = h2_config_sgeti(s, H2_CONF_STREAM_MAX_MEM); + + m->streams = h2_ihash_create(m->pool, offsetof(h2_stream,id)); + m->shold = h2_ihash_create(m->pool, offsetof(h2_stream,id)); + m->spurge = apr_array_make(m->pool, 10, sizeof(h2_stream*)); + m->q = h2_iq_create(m->pool, m->max_streams); + + m->workers = workers; + m->processing_max = H2MIN(h2_workers_get_max_workers(workers), m->max_streams); + m->processing_limit = 6; /* the original h1 max parallel connections */ + m->last_mood_change = apr_time_now(); + m->mood_update_interval = apr_time_from_msec(100); + + status = mplx_pollset_create(m); + if (APR_SUCCESS != status) { + ap_log_cerror(APLOG_MARK, APLOG_ERR, status, m->c1, APLOGNO(10308) + "nghttp2: could not create pollset"); + goto failure; + } + m->streams_ev_in = apr_array_make(m->pool, 10, sizeof(h2_stream*)); + m->streams_ev_out = apr_array_make(m->pool, 10, sizeof(h2_stream*)); + + m->streams_input_read = h2_iq_create(m->pool, 10); + m->streams_output_written = h2_iq_create(m->pool, 10); + status = apr_thread_mutex_create(&m->poll_lock, APR_THREAD_MUTEX_DEFAULT, + m->pool); + if (APR_SUCCESS != status) goto failure; + + conn_ctx = h2_conn_ctx_get(m->c1); + if (conn_ctx->pfd.reqevents) { + apr_pollset_add(m->pollset, &conn_ctx->pfd); + } + + m->scratch_r = apr_pcalloc(m->pool, sizeof(*m->scratch_r)); + m->max_spare_transits = 3; + m->c2_transits = apr_array_make(m->pool, (int)m->max_spare_transits, + sizeof(h2_c2_transit*)); + + m->producer = h2_workers_register(workers, m->pool, + apr_psprintf(m->pool, "h2-%u", + (unsigned int)m->id), + c2_prod_next, c2_prod_done, + workers_shutdown, m); + return m; + +failure: + if (m->pool) { + apr_pool_destroy(m->pool); + } + else if (allocator) { + apr_allocator_destroy(allocator); + } + return NULL; +} + +int h2_mplx_c1_shutdown(h2_mplx *m) +{ + int max_stream_id_started = 0; + + H2_MPLX_ENTER(m); + + max_stream_id_started = m->max_stream_id_started; + /* Clear schedule queue, disabling existing streams from starting */ + h2_iq_clear(m->q); + + H2_MPLX_LEAVE(m); + return max_stream_id_started; +} + +typedef struct { + h2_mplx_stream_cb *cb; + void *ctx; +} stream_iter_ctx_t; + +static int m_stream_iter_wrap(void *ctx, void *stream) +{ + stream_iter_ctx_t *x = ctx; + return x->cb(stream, x->ctx); +} + +apr_status_t h2_mplx_c1_streams_do(h2_mplx *m, h2_mplx_stream_cb *cb, void *ctx) +{ + stream_iter_ctx_t x; + + H2_MPLX_ENTER(m); + + x.cb = cb; + x.ctx = ctx; + h2_ihash_iter(m->streams, m_stream_iter_wrap, &x); + + H2_MPLX_LEAVE(m); + return APR_SUCCESS; +} + +static int m_report_stream_iter(void *ctx, void *val) { + h2_mplx *m = ctx; + h2_stream *stream = val; + h2_conn_ctx_t *conn_ctx = h2_conn_ctx_get(stream->c2); + ap_log_cerror(APLOG_MARK, APLOG_WARNING, 0, m->c1, + H2_STRM_MSG(stream, "started=%d, scheduled=%d, ready=%d, out_buffer=%ld"), + !!stream->c2, stream->scheduled, h2_stream_is_ready(stream), + (long)(stream->output? h2_beam_get_buffered(stream->output) : -1)); + if (conn_ctx) { + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, m->c1, /* NO APLOGNO */ + H2_STRM_MSG(stream, "->03198: %s %s %s" + "[started=%u/done=%u]"), + conn_ctx->request->method, conn_ctx->request->authority, + conn_ctx->request->path, + apr_atomic_read32(&conn_ctx->started), + apr_atomic_read32(&conn_ctx->done)); + } + else { + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, m->c1, /* NO APLOGNO */ + H2_STRM_MSG(stream, "->03198: not started")); + } + return 1; +} + +static int m_unexpected_stream_iter(void *ctx, void *val) { + h2_mplx *m = ctx; + h2_stream *stream = val; + ap_log_cerror(APLOG_MARK, APLOG_WARNING, 0, m->c1, /* NO APLOGNO */ + H2_STRM_MSG(stream, "unexpected, started=%d, scheduled=%d, ready=%d"), + !!stream->c2, stream->scheduled, h2_stream_is_ready(stream)); + return 1; +} + +static int m_stream_cancel_iter(void *ctx, void *val) { + h2_mplx *m = ctx; + h2_stream *stream = val; + + /* take over event monitoring */ + h2_stream_set_monitor(stream, NULL); + /* Reset, should transit to CLOSED state */ + h2_stream_rst(stream, H2_ERR_NO_ERROR); + /* All connection data has been sent, simulate cleanup */ + h2_stream_dispatch(stream, H2_SEV_EOS_SENT); + m_stream_cleanup(m, stream); + return 0; +} + +void h2_mplx_c1_destroy(h2_mplx *m) +{ + apr_status_t status; + unsigned int i, wait_secs = 60; + int old_aborted; + + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, m->c1, + H2_MPLX_MSG(m, "start release")); + /* How to shut down a h2 connection: + * 0. abort and tell the workers that no more work will come from us */ + m->shutdown = m->aborted = 1; + + H2_MPLX_ENTER_ALWAYS(m); + + /* While really terminating any c2 connections, treat the master + * connection as aborted. It's not as if we could send any more data + * at this point. */ + old_aborted = m->c1->aborted; + m->c1->aborted = 1; + + /* How to shut down a h2 connection: + * 1. cancel all streams still active */ + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, 0, m->c1, + H2_MPLX_MSG(m, "release, %u/%u/%d streams (total/hold/purge), %d streams"), + h2_ihash_count(m->streams), + h2_ihash_count(m->shold), + m->spurge->nelts, m->processing_count); + while (!h2_ihash_iter(m->streams, m_stream_cancel_iter, m)) { + /* until empty */ + } + + /* 2. no more streams should be scheduled or in the active set */ + ap_assert(h2_ihash_empty(m->streams)); + ap_assert(h2_iq_empty(m->q)); + + /* 3. while workers are busy on this connection, meaning they + * are processing streams from this connection, wait on them finishing + * in order to wake us and let us check again. + * Eventually, this has to succeed. */ + if (!m->join_wait) { + apr_thread_cond_create(&m->join_wait, m->pool); + } + + for (i = 0; h2_ihash_count(m->shold) > 0; ++i) { + status = apr_thread_cond_timedwait(m->join_wait, m->lock, apr_time_from_sec(wait_secs)); + + if (APR_STATUS_IS_TIMEUP(status)) { + /* This can happen if we have very long running requests + * that do not time out on IO. */ + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, m->c1, APLOGNO(03198) + H2_MPLX_MSG(m, "waited %u sec for %u streams"), + i*wait_secs, h2_ihash_count(m->shold)); + h2_ihash_iter(m->shold, m_report_stream_iter, m); + } + } + + H2_MPLX_LEAVE(m); + h2_workers_join(m->workers, m->producer); + H2_MPLX_ENTER_ALWAYS(m); + + /* 4. With all workers done, all streams should be in spurge */ + ap_assert(m->processing_count == 0); + if (!h2_ihash_empty(m->shold)) { + ap_log_cerror(APLOG_MARK, APLOG_WARNING, 0, m->c1, APLOGNO(03516) + H2_MPLX_MSG(m, "unexpected %u streams in hold"), + h2_ihash_count(m->shold)); + h2_ihash_iter(m->shold, m_unexpected_stream_iter, m); + } + + m->c1->aborted = old_aborted; + H2_MPLX_LEAVE(m); + + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, 0, m->c1, + H2_MPLX_MSG(m, "released")); +} + +apr_status_t h2_mplx_c1_stream_cleanup(h2_mplx *m, h2_stream *stream, + unsigned int *pstream_count) +{ + H2_MPLX_ENTER(m); + + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, m->c1, + H2_STRM_MSG(stream, "cleanup")); + m_stream_cleanup(m, stream); + *pstream_count = h2_ihash_count(m->streams); + H2_MPLX_LEAVE(m); + return APR_SUCCESS; +} + +const h2_stream *h2_mplx_c2_stream_get(h2_mplx *m, int stream_id) +{ + h2_stream *s = NULL; + + H2_MPLX_ENTER_ALWAYS(m); + s = h2_ihash_get(m->streams, stream_id); + H2_MPLX_LEAVE(m); + + return s; +} + + +static void c1_update_scoreboard(h2_mplx *m, h2_stream *stream) +{ + if (stream->c2) { + m->scratch_r->connection = stream->c2; + m->scratch_r->bytes_sent = stream->out_frame_octets; + ap_increment_counts(m->c1->sbh, m->scratch_r); + m->scratch_r->connection = NULL; + } +} + +static void c1_purge_streams(h2_mplx *m) +{ + h2_stream *stream; + int i; + + for (i = 0; i < m->spurge->nelts; ++i) { + stream = APR_ARRAY_IDX(m->spurge, i, h2_stream*); + ap_assert(stream->state == H2_SS_CLEANUP); + + c1_update_scoreboard(m, stream); + + if (stream->input) { + h2_beam_destroy(stream->input, m->c1); + stream->input = NULL; + } + if (stream->c2) { + conn_rec *c2 = stream->c2; + h2_conn_ctx_t *c2_ctx = h2_conn_ctx_get(c2); + h2_c2_transit *transit; + + stream->c2 = NULL; + ap_assert(c2_ctx); + transit = c2_ctx->transit; + h2_c2_destroy(c2); /* c2_ctx is gone as well */ + if (transit) { + c2_transit_recycle(m, transit); + } + } + h2_stream_destroy(stream); + } + apr_array_clear(m->spurge); +} + +apr_status_t h2_mplx_c1_poll(h2_mplx *m, apr_interval_time_t timeout, + stream_ev_callback *on_stream_input, + stream_ev_callback *on_stream_output, + void *on_ctx) +{ + apr_status_t rv; + + H2_MPLX_ENTER(m); + + if (m->aborted) { + rv = APR_ECONNABORTED; + goto cleanup; + } + /* Purge (destroy) streams outside of pollset processing. + * Streams that are registered in the pollset, will be removed + * when they are destroyed, but the pollset works on copies + * of these registrations. So, if we destroy streams while + * processing pollset events, we might access freed memory. + */ + if (m->spurge->nelts) { + c1_purge_streams(m); + } + rv = mplx_pollset_poll(m, timeout, on_stream_input, on_stream_output, on_ctx); + +cleanup: + H2_MPLX_LEAVE(m); + return rv; +} + +apr_status_t h2_mplx_c1_reprioritize(h2_mplx *m, h2_stream_pri_cmp_fn *cmp, + h2_session *session) +{ + apr_status_t status; + + H2_MPLX_ENTER(m); + + if (m->aborted) { + status = APR_ECONNABORTED; + } + else { + h2_iq_sort(m->q, cmp, session); + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, 0, m->c1, + H2_MPLX_MSG(m, "reprioritize streams")); + status = APR_SUCCESS; + } + + H2_MPLX_LEAVE(m); + return status; +} + +static apr_status_t c1_process_stream(h2_mplx *m, + h2_stream *stream, + h2_stream_pri_cmp_fn *cmp, + h2_session *session) +{ + apr_status_t rv = APR_SUCCESS; + + if (m->aborted) { + rv = APR_ECONNABORTED; + goto cleanup; + } + if (!stream->request) { + rv = APR_EINVAL; + goto cleanup; + } + if (APLOGctrace1(m->c1)) { + const h2_request *r = stream->request; + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, 0, m->c1, + H2_STRM_MSG(stream, "process %s %s://%s%s"), + r->method, r->scheme, r->authority, r->path); + } + + stream->scheduled = 1; + h2_ihash_add(m->streams, stream); + if (h2_stream_is_ready(stream)) { + /* already have a response */ + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, 0, m->c1, + H2_STRM_MSG(stream, "process, ready already")); + } + else { + /* last chance to set anything up before stream is processed + * by worker threads. */ + rv = h2_stream_prepare_processing(stream); + if (APR_SUCCESS != rv) goto cleanup; + h2_iq_add(m->q, stream->id, cmp, session); + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, 0, m->c1, + H2_STRM_MSG(stream, "process, added to q")); + } + +cleanup: + return rv; +} + +void h2_mplx_c1_process(h2_mplx *m, + h2_iqueue *ready_to_process, + h2_stream_get_fn *get_stream, + h2_stream_pri_cmp_fn *stream_pri_cmp, + h2_session *session, + unsigned int *pstream_count) +{ + apr_status_t rv; + int sid; + + H2_MPLX_ENTER_ALWAYS(m); + + while ((sid = h2_iq_shift(ready_to_process)) > 0) { + h2_stream *stream = get_stream(session, sid); + if (stream) { + ap_assert(!stream->scheduled); + rv = c1_process_stream(session->mplx, stream, stream_pri_cmp, session); + if (APR_SUCCESS != rv) { + h2_stream_rst(stream, H2_ERR_INTERNAL_ERROR); + } + } + else { + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, 0, m->c1, + H2_MPLX_MSG(m, "stream %d not found to process"), sid); + } + } + if ((m->processing_count < m->processing_limit) && !h2_iq_empty(m->q)) { + H2_MPLX_LEAVE(m); + rv = h2_workers_activate(m->workers, m->producer); + H2_MPLX_ENTER_ALWAYS(m); + if (rv != APR_SUCCESS) { + ap_log_cerror(APLOG_MARK, APLOG_ERR, rv, m->c1, APLOGNO(10021) + H2_MPLX_MSG(m, "activate at workers")); + } + } + *pstream_count = h2_ihash_count(m->streams); + +#if APR_POOL_DEBUG + do { + apr_size_t mem_g, mem_m, mem_s, mem_c1; + + mem_g = pchild? apr_pool_num_bytes(pchild, 1) : 0; + mem_m = apr_pool_num_bytes(m->pool, 1); + mem_s = apr_pool_num_bytes(session->pool, 1); + mem_c1 = apr_pool_num_bytes(m->c1->pool, 1); + ap_log_cerror(APLOG_MARK, APLOG_INFO, 0, m->c1, + H2_MPLX_MSG(m, "child mem=%ld, mplx mem=%ld, session mem=%ld, c1=%ld"), + (long)mem_g, (long)mem_m, (long)mem_s, (long)mem_c1); + + } while (0); +#endif + + H2_MPLX_LEAVE(m); +} + +static void c2_beam_input_write_notify(void *ctx, h2_bucket_beam *beam) +{ + conn_rec *c = ctx; + h2_conn_ctx_t *conn_ctx = h2_conn_ctx_get(c); + + (void)beam; + if (conn_ctx && conn_ctx->stream_id && conn_ctx->pipe_in[H2_PIPE_IN]) { + apr_file_putc(1, conn_ctx->pipe_in[H2_PIPE_IN]); + } +} + +static void add_stream_poll_event(h2_mplx *m, int stream_id, h2_iqueue *q) +{ + apr_thread_mutex_lock(m->poll_lock); + if (h2_iq_append(q, stream_id) && h2_iq_count(q) == 1) { + /* newly added first */ + apr_pollset_wakeup(m->pollset); + } + apr_thread_mutex_unlock(m->poll_lock); +} + +static void c2_beam_input_read_notify(void *ctx, h2_bucket_beam *beam) +{ + conn_rec *c = ctx; + h2_conn_ctx_t *conn_ctx = h2_conn_ctx_get(c); + + if (conn_ctx && conn_ctx->stream_id) { + add_stream_poll_event(conn_ctx->mplx, conn_ctx->stream_id, + conn_ctx->mplx->streams_input_read); + } +} + +static void c2_beam_output_write_notify(void *ctx, h2_bucket_beam *beam) +{ + conn_rec *c = ctx; + h2_conn_ctx_t *conn_ctx = h2_conn_ctx_get(c); + + if (conn_ctx && conn_ctx->stream_id) { + add_stream_poll_event(conn_ctx->mplx, conn_ctx->stream_id, + conn_ctx->mplx->streams_output_written); + } +} + +static apr_status_t c2_setup_io(h2_mplx *m, conn_rec *c2, h2_stream *stream, h2_c2_transit *transit) +{ + h2_conn_ctx_t *conn_ctx; + apr_status_t rv = APR_SUCCESS; + const char *action = "init"; + + rv = h2_conn_ctx_init_for_c2(&conn_ctx, c2, m, stream, transit); + if (APR_SUCCESS != rv) goto cleanup; + + if (!conn_ctx->beam_out) { + action = "create output beam"; + rv = h2_beam_create(&conn_ctx->beam_out, c2, conn_ctx->req_pool, + stream->id, "output", 0, c2->base_server->timeout); + if (APR_SUCCESS != rv) goto cleanup; + + h2_beam_buffer_size_set(conn_ctx->beam_out, m->stream_max_mem); + h2_beam_on_was_empty(conn_ctx->beam_out, c2_beam_output_write_notify, c2); + } + + memset(&conn_ctx->pipe_in, 0, sizeof(conn_ctx->pipe_in)); + if (stream->input) { + conn_ctx->beam_in = stream->input; + h2_beam_on_send(stream->input, c2_beam_input_write_notify, c2); + h2_beam_on_received(stream->input, c2_beam_input_read_notify, c2); + h2_beam_on_consumed(stream->input, c1_input_consumed, stream); +#if H2_USE_PIPES + action = "create input write pipe"; + rv = apr_file_pipe_create_pools(&conn_ctx->pipe_in[H2_PIPE_OUT], + &conn_ctx->pipe_in[H2_PIPE_IN], + APR_READ_BLOCK, + c2->pool, c2->pool); + if (APR_SUCCESS != rv) goto cleanup; +#endif + } + +cleanup: + stream->output = (APR_SUCCESS == rv)? conn_ctx->beam_out : NULL; + if (APR_SUCCESS != rv) { + ap_log_cerror(APLOG_MARK, APLOG_ERR, rv, c2, + H2_STRM_LOG(APLOGNO(10309), stream, + "error %s"), action); + } + return rv; +} + +static conn_rec *s_next_c2(h2_mplx *m) +{ + h2_stream *stream = NULL; + apr_status_t rv = APR_SUCCESS; + apr_uint32_t sid; + conn_rec *c2 = NULL; + h2_c2_transit *transit = NULL; + + while (!m->aborted && !stream && (m->processing_count < m->processing_limit) + && (sid = h2_iq_shift(m->q)) > 0) { + stream = h2_ihash_get(m->streams, sid); + } + + if (!stream) { + if (m->processing_count >= m->processing_limit && !h2_iq_empty(m->q)) { + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, m->c1, + H2_MPLX_MSG(m, "delaying request processing. " + "Current limit is %d and %d workers are in use."), + m->processing_limit, m->processing_count); + } + goto cleanup; + } + + if (sid > m->max_stream_id_started) { + m->max_stream_id_started = sid; + } + + transit = c2_transit_get(m); +#if AP_HAS_RESPONSE_BUCKETS + c2 = ap_create_secondary_connection(transit->pool, m->c1, transit->bucket_alloc); +#else + c2 = h2_c2_create(m->c1, transit->pool, transit->bucket_alloc); +#endif + if (!c2) goto cleanup; + ap_log_cerror(APLOG_MARK, APLOG_TRACE3, 0, m->c1, + H2_STRM_MSG(stream, "created new c2")); + + rv = c2_setup_io(m, c2, stream, transit); + if (APR_SUCCESS != rv) goto cleanup; + + stream->c2 = c2; + ++m->processing_count; + +cleanup: + if (APR_SUCCESS != rv && c2) { + h2_c2_destroy(c2); + c2 = NULL; + } + if (transit && !c2) { + c2_transit_recycle(m, transit); + } + return c2; +} + +static conn_rec *c2_prod_next(void *baton, int *phas_more) +{ + h2_mplx *m = baton; + conn_rec *c = NULL; + + H2_MPLX_ENTER_ALWAYS(m); + if (!m->aborted) { + c = s_next_c2(m); + *phas_more = (c != NULL && !h2_iq_empty(m->q)); + } + H2_MPLX_LEAVE(m); + return c; +} + +static void s_c2_done(h2_mplx *m, conn_rec *c2, h2_conn_ctx_t *conn_ctx) +{ + h2_stream *stream; + + ap_assert(conn_ctx); + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, 0, c2, + "h2_mplx(%s-%d): c2 done", conn_ctx->id, conn_ctx->stream_id); + + AP_DEBUG_ASSERT(apr_atomic_read32(&conn_ctx->done) == 0); + apr_atomic_set32(&conn_ctx->done, 1); + conn_ctx->done_at = apr_time_now(); + ++c2->keepalives; + /* From here on, the final handling of c2 is done by c1 processing. + * Which means we can give it c1's scoreboard handle for updates. */ + c2->sbh = m->c1->sbh; + + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, c2, + "h2_mplx(%s-%d): request done, %f ms elapsed", + conn_ctx->id, conn_ctx->stream_id, + (conn_ctx->done_at - conn_ctx->started_at) / 1000.0); + + if (!conn_ctx->has_final_response) { + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, conn_ctx->last_err, c2, + "h2_c2(%s-%d): processing finished without final response", + conn_ctx->id, conn_ctx->stream_id); + c2->aborted = 1; + } + else if (!c2->aborted) { + s_mplx_be_happy(m, c2, conn_ctx); + } + + stream = h2_ihash_get(m->streams, conn_ctx->stream_id); + if (stream) { + /* stream not done yet. trigger a potential polling on the output + * since nothing more will happening here. */ + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, c2, + H2_STRM_MSG(stream, "c2_done, stream open")); + c2_beam_output_write_notify(c2, NULL); + } + else if ((stream = h2_ihash_get(m->shold, conn_ctx->stream_id)) != NULL) { + /* stream is done, was just waiting for this. */ + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, c2, + H2_STRM_MSG(stream, "c2_done, in hold")); + c1c2_stream_joined(m, stream); + } + else { + int i; + + for (i = 0; i < m->spurge->nelts; ++i) { + if (stream == APR_ARRAY_IDX(m->spurge, i, h2_stream*)) { + ap_log_cerror(APLOG_MARK, APLOG_WARNING, 0, c2, + H2_STRM_LOG(APLOGNO(03517), stream, "already in spurge")); + ap_assert("stream should not be in spurge" == NULL); + return; + } + } + + ap_log_cerror(APLOG_MARK, APLOG_WARNING, 0, c2, APLOGNO(03518) + "h2_mplx(%s-%d): c2_done, stream not found", + conn_ctx->id, conn_ctx->stream_id); + ap_assert("stream should still be available" == NULL); + } +} + +static void c2_prod_done(void *baton, conn_rec *c2) +{ + h2_mplx *m = baton; + h2_conn_ctx_t *conn_ctx = h2_conn_ctx_get(c2); + + AP_DEBUG_ASSERT(conn_ctx); + H2_MPLX_ENTER_ALWAYS(m); + + --m->processing_count; + s_c2_done(m, c2, conn_ctx); + if (m->join_wait) apr_thread_cond_signal(m->join_wait); + + H2_MPLX_LEAVE(m); +} + +static void workers_shutdown(void *baton, int graceful) +{ + h2_mplx *m = baton; + + apr_thread_mutex_lock(m->poll_lock); + /* time to wakeup and assess what to do */ + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, m->c1, + H2_MPLX_MSG(m, "workers shutdown, waking pollset")); + m->shutdown = 1; + if (!graceful) { + m->aborted = 1; + } + apr_pollset_wakeup(m->pollset); + apr_thread_mutex_unlock(m->poll_lock); +} + +/******************************************************************************* + * h2_mplx DoS protection + ******************************************************************************/ + +static void s_mplx_be_happy(h2_mplx *m, conn_rec *c, h2_conn_ctx_t *conn_ctx) +{ + apr_time_t now; + + if (m->processing_limit < m->processing_max + && conn_ctx->started_at > m->last_mood_change) { + --m->irritations_since; + if (m->processing_limit < m->processing_max + && ((now = apr_time_now()) - m->last_mood_change >= m->mood_update_interval + || m->irritations_since < -m->processing_limit)) { + m->processing_limit = H2MIN(m->processing_limit * 2, m->processing_max); + m->last_mood_change = now; + m->irritations_since = 0; + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, 0, c, + H2_MPLX_MSG(m, "mood update, increasing worker limit to %d"), + m->processing_limit); + } + } +} + +static void m_be_annoyed(h2_mplx *m) +{ + apr_time_t now; + + if (m->processing_limit > 2) { + ++m->irritations_since; + if (((now = apr_time_now()) - m->last_mood_change >= m->mood_update_interval) + || (m->irritations_since >= m->processing_limit)) { + + if (m->processing_limit > 16) { + m->processing_limit = 16; + } + else if (m->processing_limit > 8) { + m->processing_limit = 8; + } + else if (m->processing_limit > 4) { + m->processing_limit = 4; + } + else if (m->processing_limit > 2) { + m->processing_limit = 2; + } + m->last_mood_change = now; + m->irritations_since = 0; + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, 0, m->c1, + H2_MPLX_MSG(m, "mood update, decreasing worker limit to %d"), + m->processing_limit); + } + } +} + +/******************************************************************************* + * mplx master events dispatching + ******************************************************************************/ + +static int reset_is_acceptable(h2_stream *stream) +{ + /* client may terminate a stream via H2 RST_STREAM message at any time. + * This is annyoing when we have committed resources (e.g. worker threads) + * to it, so our mood (e.g. willingness to commit resources on this + * connection in the future) goes down. + * + * This is a DoS protection. We do not want to make it too easy for + * a client to eat up server resources. + * + * However: there are cases where a RST_STREAM is the only way to end + * a request. This includes websockets and server-side-event streams (SSEs). + * The responses to such requests continue forever otherwise. + * + */ + if (!stream_is_running(stream)) return 1; + if (!(stream->id & 0x01)) return 1; /* stream initiated by us. acceptable. */ + if (!stream->response) return 0; /* no response headers produced yet. bad. */ + if (!stream->out_data_frames) return 0; /* no response body data sent yet. bad. */ + return 1; /* otherwise, be forgiving */ +} + +apr_status_t h2_mplx_c1_client_rst(h2_mplx *m, int stream_id) +{ + h2_stream *stream; + apr_status_t status = APR_SUCCESS; + + H2_MPLX_ENTER_ALWAYS(m); + stream = h2_ihash_get(m->streams, stream_id); + if (stream && !reset_is_acceptable(stream)) { + m_be_annoyed(m); + } + H2_MPLX_LEAVE(m); + return status; +} + +static apr_status_t mplx_pollset_create(h2_mplx *m) +{ + /* stream0 output only */ + return apr_pollset_create(&m->pollset, 1, m->pool, + APR_POLLSET_WAKEABLE); +} + +static apr_status_t mplx_pollset_poll(h2_mplx *m, apr_interval_time_t timeout, + stream_ev_callback *on_stream_input, + stream_ev_callback *on_stream_output, + void *on_ctx) +{ + apr_status_t rv; + const apr_pollfd_t *results, *pfd; + apr_int32_t nresults, i; + h2_conn_ctx_t *conn_ctx; + h2_stream *stream; + + /* Make sure we are not called recursively. */ + ap_assert(!m->polling); + m->polling = 1; + do { + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, m->c1, + H2_MPLX_MSG(m, "enter polling timeout=%d"), + (int)apr_time_sec(timeout)); + + apr_array_clear(m->streams_ev_in); + apr_array_clear(m->streams_ev_out); + + do { + /* add streams we started processing in the meantime */ + apr_thread_mutex_lock(m->poll_lock); + if (!h2_iq_empty(m->streams_input_read) + || !h2_iq_empty(m->streams_output_written)) { + while ((i = h2_iq_shift(m->streams_input_read))) { + stream = h2_ihash_get(m->streams, i); + if (stream) { + APR_ARRAY_PUSH(m->streams_ev_in, h2_stream*) = stream; + } + } + while ((i = h2_iq_shift(m->streams_output_written))) { + stream = h2_ihash_get(m->streams, i); + if (stream) { + APR_ARRAY_PUSH(m->streams_ev_out, h2_stream*) = stream; + } + } + nresults = 0; + rv = APR_SUCCESS; + apr_thread_mutex_unlock(m->poll_lock); + break; + } + apr_thread_mutex_unlock(m->poll_lock); + + H2_MPLX_LEAVE(m); + rv = apr_pollset_poll(m->pollset, timeout >= 0? timeout : -1, &nresults, &results); + H2_MPLX_ENTER_ALWAYS(m); + if (APR_STATUS_IS_EINTR(rv) && m->shutdown) { + if (!m->aborted) { + rv = APR_SUCCESS; + } + goto cleanup; + } + } while (APR_STATUS_IS_EINTR(rv)); + + if (APR_SUCCESS != rv) { + if (APR_STATUS_IS_TIMEUP(rv)) { + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, m->c1, + H2_MPLX_MSG(m, "polling timed out ")); + } + else { + ap_log_cerror(APLOG_MARK, APLOG_ERR, rv, m->c1, APLOGNO(10310) \ + H2_MPLX_MSG(m, "polling failed")); + } + goto cleanup; + } + + for (i = 0; i < nresults; i++) { + pfd = &results[i]; + conn_ctx = pfd->client_data; + + AP_DEBUG_ASSERT(conn_ctx); + if (conn_ctx->stream_id == 0) { + if (on_stream_input) { + APR_ARRAY_PUSH(m->streams_ev_in, h2_stream*) = m->stream0; + } + continue; + } + } + + if (on_stream_input && m->streams_ev_in->nelts) { + H2_MPLX_LEAVE(m); + for (i = 0; i < m->streams_ev_in->nelts; ++i) { + on_stream_input(on_ctx, APR_ARRAY_IDX(m->streams_ev_in, i, h2_stream*)); + } + H2_MPLX_ENTER_ALWAYS(m); + } + if (on_stream_output && m->streams_ev_out->nelts) { + H2_MPLX_LEAVE(m); + for (i = 0; i < m->streams_ev_out->nelts; ++i) { + on_stream_output(on_ctx, APR_ARRAY_IDX(m->streams_ev_out, i, h2_stream*)); + } + H2_MPLX_ENTER_ALWAYS(m); + } + break; + } while(1); + +cleanup: + m->polling = 0; + return rv; +} + |