diff options
Diffstat (limited to 'src/spdk/lib/trace/trace.c')
| -rw-r--r-- | src/spdk/lib/trace/trace.c | 201 |
1 files changed, 201 insertions, 0 deletions
diff --git a/src/spdk/lib/trace/trace.c b/src/spdk/lib/trace/trace.c new file mode 100644 index 000000000..621c52aae --- /dev/null +++ b/src/spdk/lib/trace/trace.c @@ -0,0 +1,201 @@ +/*- + * BSD LICENSE + * + * Copyright (c) Intel Corporation. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include "spdk/stdinc.h" + +#include "spdk/env.h" +#include "spdk/string.h" +#include "spdk/trace.h" +#include "spdk/util.h" +#include "spdk/barrier.h" +#include "spdk/log.h" + +static int g_trace_fd = -1; +static char g_shm_name[64]; + +struct spdk_trace_histories *g_trace_histories; + +void +_spdk_trace_record(uint64_t tsc, uint16_t tpoint_id, uint16_t poller_id, uint32_t size, + uint64_t object_id, uint64_t arg1) +{ + struct spdk_trace_history *lcore_history; + struct spdk_trace_entry *next_entry; + unsigned lcore; + uint64_t next_circular_entry; + + lcore = spdk_env_get_current_core(); + if (lcore >= SPDK_TRACE_MAX_LCORE) { + return; + } + + lcore_history = spdk_get_per_lcore_history(g_trace_histories, lcore); + if (tsc == 0) { + tsc = spdk_get_ticks(); + } + + lcore_history->tpoint_count[tpoint_id]++; + + /* Get next entry index in the circular buffer */ + next_circular_entry = lcore_history->next_entry & (lcore_history->num_entries - 1); + next_entry = &lcore_history->entries[next_circular_entry]; + next_entry->tsc = tsc; + next_entry->tpoint_id = tpoint_id; + next_entry->poller_id = poller_id; + next_entry->size = size; + next_entry->object_id = object_id; + next_entry->arg1 = arg1; + + /* Ensure all elements of the trace entry are visible to outside trace tools */ + spdk_smp_wmb(); + lcore_history->next_entry++; +} + +int +spdk_trace_init(const char *shm_name, uint64_t num_entries) +{ + int i = 0; + int histories_size; + uint64_t lcore_offsets[SPDK_TRACE_MAX_LCORE + 1]; + + /* 0 entries requested - skip trace initialization */ + if (num_entries == 0) { + return 0; + } + + lcore_offsets[0] = sizeof(struct spdk_trace_flags); + for (i = 1; i < (int)SPDK_COUNTOF(lcore_offsets); i++) { + lcore_offsets[i] = spdk_get_trace_history_size(num_entries) + lcore_offsets[i - 1]; + } + histories_size = lcore_offsets[SPDK_TRACE_MAX_LCORE]; + + snprintf(g_shm_name, sizeof(g_shm_name), "%s", shm_name); + + g_trace_fd = shm_open(shm_name, O_RDWR | O_CREAT, 0600); + if (g_trace_fd == -1) { + SPDK_ERRLOG("could not shm_open spdk_trace\n"); + SPDK_ERRLOG("errno=%d %s\n", errno, spdk_strerror(errno)); + return 1; + } + + if (ftruncate(g_trace_fd, histories_size) != 0) { + SPDK_ERRLOG("could not truncate shm\n"); + goto trace_init_err; + } + + g_trace_histories = mmap(NULL, histories_size, PROT_READ | PROT_WRITE, + MAP_SHARED, g_trace_fd, 0); + if (g_trace_histories == MAP_FAILED) { + SPDK_ERRLOG("could not mmap shm\n"); + goto trace_init_err; + } + + /* TODO: On FreeBSD, mlock on shm_open'd memory doesn't seem to work. Docs say that kern.ipc.shm_use_phys=1 + * should allow it, but forcing that doesn't seem to work either. So for now just skip mlock on FreeBSD + * altogether. + */ +#if defined(__linux__) + if (mlock(g_trace_histories, histories_size) != 0) { + SPDK_ERRLOG("Could not mlock shm for tracing - %s.\n", spdk_strerror(errno)); + if (errno == ENOMEM) { + SPDK_ERRLOG("Check /dev/shm for old tracing files that can be deleted.\n"); + } + goto trace_init_err; + } +#endif + + memset(g_trace_histories, 0, histories_size); + + g_trace_flags = &g_trace_histories->flags; + + g_trace_flags->tsc_rate = spdk_get_ticks_hz(); + + for (i = 0; i < SPDK_TRACE_MAX_LCORE; i++) { + struct spdk_trace_history *lcore_history; + + g_trace_flags->lcore_history_offsets[i] = lcore_offsets[i]; + lcore_history = spdk_get_per_lcore_history(g_trace_histories, i); + lcore_history->lcore = i; + lcore_history->num_entries = num_entries; + } + g_trace_flags->lcore_history_offsets[SPDK_TRACE_MAX_LCORE] = lcore_offsets[SPDK_TRACE_MAX_LCORE]; + + spdk_trace_flags_init(); + + return 0; + +trace_init_err: + if (g_trace_histories != MAP_FAILED) { + munmap(g_trace_histories, histories_size); + } + close(g_trace_fd); + g_trace_fd = -1; + shm_unlink(shm_name); + g_trace_histories = NULL; + + return 1; + +} + +void +spdk_trace_cleanup(void) +{ + bool unlink; + int i; + struct spdk_trace_history *lcore_history; + + if (g_trace_histories == NULL) { + return; + } + + /* + * Only unlink the shm if there were no trace_entry recorded. This ensures the file + * can be used after this process exits/crashes for debugging. + * Note that we have to calculate this value before g_trace_histories gets unmapped. + */ + for (i = 0; i < SPDK_TRACE_MAX_LCORE; i++) { + lcore_history = spdk_get_per_lcore_history(g_trace_histories, i); + unlink = lcore_history->entries[0].tsc == 0; + if (!unlink) { + break; + } + } + + munmap(g_trace_histories, sizeof(struct spdk_trace_histories)); + g_trace_histories = NULL; + close(g_trace_fd); + + if (unlink) { + shm_unlink(g_shm_name); + } +} |