123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357 |
- /*
- * udebug - debug ring buffer library
- *
- * Copyright (C) 2023 Felix Fietkau <nbd@nbd.name>
- *
- * Permission to use, copy, modify, and/or distribute this software for any
- * purpose with or without fee is hereby granted, provided that the above
- * copyright notice and this permission notice appear in all copies.
- *
- * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
- * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
- * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
- * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
- * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
- * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
- */
- #include "udebug-priv.h"
- static int
- udebug_remote_get_handle(struct udebug *ctx)
- {
- struct udebug_client_msg *msg;
- struct udebug_client_msg send_msg = {
- .type = CL_MSG_GET_HANDLE,
- };
- if (ctx->poll_handle >= 0 || !udebug_is_connected(ctx))
- return 0;
- msg = udebug_send_and_wait(ctx, &send_msg, NULL);
- if (!msg)
- return -1;
- ctx->poll_handle = msg->id;
- return 0;
- }
- struct udebug_remote_buf *udebug_remote_buf_get(struct udebug *ctx, uint32_t id)
- {
- struct udebug_remote_buf *rb;
- void *key = (void *)(uintptr_t)id;
- return avl_find_element(&ctx->remote_rings, key, rb, node);
- }
- int udebug_remote_buf_map(struct udebug *ctx, struct udebug_remote_buf *rb, uint32_t id)
- {
- void *key = (void *)(uintptr_t)id;
- struct udebug_client_msg *msg;
- struct udebug_client_msg send_msg = {
- .type = CL_MSG_RING_GET,
- .id = id,
- };
- int fd = -1;
- if (rb->buf.data || !udebug_is_connected(ctx))
- return -1;
- msg = udebug_send_and_wait(ctx, &send_msg, &fd);
- if (!msg || fd < 0)
- return -1;
- if (udebug_buf_open(&rb->buf, fd, msg->ring_size, msg->data_size)) {
- fprintf(stderr, "failed to open fd %d, ring_size=%d, data_size=%d\n", fd, msg->ring_size, msg->data_size);
- close(fd);
- return -1;
- }
- rb->pcap_iface = ~0;
- rb->node.key = key;
- avl_insert(&ctx->remote_rings, &rb->node);
- return 0;
- }
- void udebug_remote_buf_unmap(struct udebug *ctx, struct udebug_remote_buf *rb)
- {
- if (!rb->buf.data)
- return;
- avl_delete(&ctx->remote_rings, &rb->node);
- udebug_buf_free(&rb->buf);
- rb->poll = 0;
- rb->node.key = NULL;
- rb->pcap_iface = ~0;
- }
- int udebug_remote_buf_set_poll(struct udebug *ctx, struct udebug_remote_buf *rb, bool val)
- {
- int handle;
- if (!rb->buf.data)
- return -1;
- if (rb->poll == val)
- return 0;
- rb->poll = val;
- if (!val)
- return 0;
- handle = udebug_remote_get_handle(ctx);
- if (handle < 0)
- return -1;
- __atomic_fetch_or(&rb->buf.hdr->notify, 1UL << handle, __ATOMIC_RELAXED);
- return 0;
- }
- static void
- rbuf_advance_read_head(struct udebug_remote_buf *rb, uint32_t head,
- uint32_t *data_start)
- {
- struct udebug_hdr *hdr = rb->buf.hdr;
- uint32_t min_head = head + 1 - rb->buf.ring_size;
- uint32_t min_data = u32_get(&hdr->data_used) - rb->buf.data_size;
- struct udebug_ptr *last_ptr = udebug_ring_ptr(hdr, head - 1);
- if (!u32_get(&hdr->head_hi) && u32_sub(0, min_head) > 0)
- min_head = 0;
- /* advance head to skip over any entries that are guaranteed
- * to be overwritten now. final check will be performed after
- * data copying */
- if (u32_sub(rb->head, min_head) < 0)
- rb->head = min_head;
- for (size_t i = 0; i < rb->buf.ring_size; i++) {
- struct udebug_ptr *ptr = udebug_ring_ptr(hdr, rb->head);
- if (data_start) {
- *data_start = u32_get(&ptr->start);
- __sync_synchronize();
- }
- if (ptr->timestamp > last_ptr->timestamp)
- continue;
- if (u32_sub(ptr->start, min_data) > 0)
- break;
- rb->head++;
- }
- }
- void udebug_remote_buf_set_start_time(struct udebug_remote_buf *rb, uint64_t ts)
- {
- struct udebug_hdr *hdr = rb->buf.hdr;
- uint32_t head = u32_get(&hdr->head);
- uint32_t start = rb->head, end = head;
- uint32_t diff;
- if (!hdr)
- return;
- rbuf_advance_read_head(rb, head, NULL);
- while ((diff = u32_sub(end, start)) > 0) {
- uint32_t cur = start + diff / 2;
- struct udebug_ptr *ptr;
- ptr = udebug_ring_ptr(hdr, cur);
- if (ptr->timestamp > ts)
- end = cur - 1;
- else
- start = cur + 1;
- }
- rb->head = start;
- }
- void udebug_remote_buf_set_start_offset(struct udebug_remote_buf *rb, uint32_t idx)
- {
- if (!rb->buf.hdr)
- return;
- rb->head = rb->buf.hdr->head - idx;
- }
- void udebug_remote_buf_set_flags(struct udebug_remote_buf *rb, uint64_t mask, uint64_t set)
- {
- struct udebug_hdr *hdr = rb->buf.hdr;
- if (!hdr)
- return;
- if ((uintptr_t)mask)
- __atomic_and_fetch(&hdr->flags[0], (uintptr_t)~mask, __ATOMIC_RELAXED);
- if ((uintptr_t)set)
- __atomic_or_fetch(&hdr->flags[0], (uintptr_t)set, __ATOMIC_RELAXED);
- if (sizeof(mask) == sizeof(unsigned long))
- return;
- mask >>= 32;
- if ((uintptr_t)mask)
- __atomic_and_fetch(&hdr->flags[1], (uintptr_t)~mask, __ATOMIC_RELAXED);
- if ((uintptr_t)set)
- __atomic_or_fetch(&hdr->flags[1], (uintptr_t)set, __ATOMIC_RELAXED);
- }
- struct udebug_snapshot *
- udebug_remote_buf_snapshot(struct udebug_remote_buf *rb)
- {
- struct udebug_hdr *hdr = rb->buf.hdr;
- struct udebug_ptr *last_ptr;
- uint32_t data_start, data_end, data_used;
- struct udebug_snapshot *s = NULL;
- struct udebug_ptr *ptr_buf, *first_ptr;
- uint32_t data_size, ptr_size;
- uint32_t head, first_idx;
- uint32_t prev_read_head = rb->head;
- void *data_buf;
- if (!hdr)
- return NULL;
- head = u32_get(&hdr->head);
- rbuf_advance_read_head(rb, head, &data_start);
- if (rb->head == head)
- return NULL;
- first_idx = rb->head;
- first_ptr = udebug_ring_ptr(hdr, first_idx);
- last_ptr = udebug_ring_ptr(hdr, head - 1);
- data_end = last_ptr->start + last_ptr->len;
- data_size = data_end - data_start;
- ptr_size = head - rb->head;
- if (data_size > rb->buf.data_size || ptr_size > rb->buf.ring_size) {
- fprintf(stderr, "Invalid data size: %x > %x, %x > %x\n", data_size, (int)rb->buf.data_size, ptr_size, (int)rb->buf.ring_size);
- goto out;
- }
- s = calloc_a(sizeof(*s),
- &ptr_buf, ptr_size * sizeof(*ptr_buf),
- &data_buf, data_size);
- s->data = memcpy(data_buf, udebug_buf_ptr(&rb->buf, data_start), data_size);
- s->data_size = data_size;
- s->entries = ptr_buf;
- s->dropped = rb->head - prev_read_head;
- if (first_ptr > last_ptr) {
- struct udebug_ptr *start_ptr = udebug_ring_ptr(hdr, 0);
- struct udebug_ptr *end_ptr = udebug_ring_ptr(hdr, rb->buf.ring_size - 1) + 1;
- uint32_t size = end_ptr - first_ptr;
- memcpy(s->entries, first_ptr, size * sizeof(*s->entries));
- memcpy(s->entries + size, start_ptr, (last_ptr + 1 - start_ptr) * sizeof(*s->entries));
- } else {
- memcpy(s->entries, first_ptr, (last_ptr + 1 - first_ptr) * sizeof(*s->entries));
- }
- /* get a snapshot of the counter that indicates how much data has been
- * clobbered by newly added entries */
- __sync_synchronize();
- data_used = u32_get(&hdr->data_used) - rb->buf.data_size;
- s->n_entries = head - first_idx;
- rbuf_advance_read_head(rb, head, NULL);
- if (s->n_entries < rb->head - first_idx) {
- free(s);
- s = NULL;
- goto out;
- }
- s->entries += rb->head - first_idx;
- s->n_entries -= rb->head - first_idx;
- while (s->n_entries > 0 &&
- u32_sub(s->entries[0].start, data_used) < 0) {
- s->entries++;
- s->n_entries--;
- s->dropped++;
- }
- for (size_t i = 0; i < s->n_entries; i++)
- s->entries[i].start -= data_start;
- s->format = hdr->format;
- s->sub_format = hdr->sub_format;
- s->rbuf_idx = (uint32_t)(uintptr_t)rb->node.key;
- out:
- rb->head = head;
- return s;
- }
- bool udebug_snapshot_get_entry(struct udebug_snapshot *s, struct udebug_iter *it, unsigned int entry)
- {
- struct udebug_ptr *ptr;
- it->len = 0;
- if (entry >= s->n_entries)
- goto error;
- ptr = &s->entries[entry];
- if (ptr->start > s->data_size || ptr->len > s->data_size ||
- ptr->start + ptr->len > s->data_size)
- goto error;
- it->s = s;
- it->data = s->data + ptr->start;
- it->len = ptr->len;
- it->timestamp = ptr->timestamp;
- return true;
- error:
- it->data = NULL;
- return false;
- }
- void udebug_iter_start(struct udebug_iter *it, struct udebug_snapshot **s, size_t n)
- {
- memset(it, 0, sizeof(*it));
- it->list = s;
- it->n = n;
- for (size_t i = 0; i < it->n; i++)
- it->list[i]->iter_idx = 0;
- }
- bool udebug_iter_next(struct udebug_iter *it)
- {
- while (1) {
- struct udebug_snapshot *s;
- uint64_t cur_ts;
- int cur = -1;
- for (size_t i = 0; i < it->n; i++) {
- struct udebug_ptr *ptr;
- s = it->list[i];
- if (s->iter_idx >= s->n_entries)
- continue;
- ptr = &s->entries[s->iter_idx];
- if (cur >= 0 && ptr->timestamp > cur_ts)
- continue;
- cur = i;
- cur_ts = ptr->timestamp;
- }
- if (cur < 0)
- return false;
- s = it->list[cur];
- it->s_idx = cur;
- if (!udebug_snapshot_get_entry(s, it, s->iter_idx++))
- continue;
- return true;
- }
- }
|