X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fust-clock.h;h=91cbbe62862261401038776da5297557f1dfe130;hp=c2e0cbcc394a9708f16801802761169e8cd0ea6d;hb=ddd915a3dd0eeb1667286051cc1e17017436fe5e;hpb=1cf9656cf8f53a69a8be83cb76c0ee3de64b0db8 diff --git a/src/bin/lttng-sessiond/ust-clock.h b/src/bin/lttng-sessiond/ust-clock.h index c2e0cbcc3..91cbbe628 100644 --- a/src/bin/lttng-sessiond/ust-clock.h +++ b/src/bin/lttng-sessiond/ust-clock.h @@ -1,26 +1,15 @@ /* - * Copyright (C) 2010 Pierre-Marc Fournier - * Copyright (C) 2011 Mathieu Desnoyers + * Copyright (C) 2010 Pierre-Marc Fournier + * Copyright (C) 2011 Mathieu Desnoyers * - * This library is free software; you can redistribute it and/or - * modify it under the terms of the GNU Lesser General Public - * License as published by the Free Software Foundation; version 2.1 of - * the License. + * SPDX-License-Identifier: GPL-2.0-only * - * This library is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * Lesser General Public License for more details. - * - * You should have received a copy of the GNU Lesser General Public - * License along with this library; if not, write to the Free Software - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef _UST_CLOCK_H #define _UST_CLOCK_H -#include +#include #include #include #include @@ -29,152 +18,85 @@ #include #include -#include - -/* TRACE CLOCK */ - -struct lttng_trace_clock { - uint64_t (*read64)(void); - uint64_t (*freq)(void); - int (*uuid)(char *uuid); - const char *(*name)(void); - const char *(*description)(void); -}; - -extern struct lttng_trace_clock *lttng_trace_clock; - -void lttng_ust_clock_init(void); - -/* - * Currently using the kernel MONOTONIC clock, waiting for kernel-side - * LTTng to implement mmap'd trace clock. - */ - -/* Choosing correct trace clock */ +#include static __inline__ -uint64_t trace_clock_read64_monotonic(void) +uint64_t trace_clock_read64(void) { - struct timespec ts; + uint64_t clock_value = 0; + lttng_ust_clock_read64_function read64_cb; - if (clock_gettime(CLOCK_MONOTONIC, &ts)) { - /* TODO Report error cleanly up the chain. */ - PERROR("clock_gettime CLOCK_MONOTONIC"); - ts.tv_sec = 0; - ts.tv_nsec = 0; + if (lttng_ust_trace_clock_get_read64_cb(&read64_cb)) { + goto end; } - return ((uint64_t) ts.tv_sec * 1000000000ULL) + ts.tv_nsec; -} -static __inline__ -uint64_t trace_clock_freq_monotonic(void) -{ - return 1000000000ULL; + clock_value = read64_cb(); +end: + return clock_value; } static __inline__ -int trace_clock_uuid_monotonic(char *uuid) +uint64_t trace_clock_freq(void) { - int ret = 0; - size_t len; - FILE *fp; - - /* - * boot_id needs to be read once before being used concurrently - * to deal with a Linux kernel race. A fix is proposed for - * upstream, but the work-around is needed for older kernels. - */ - fp = fopen("/proc/sys/kernel/random/boot_id", "r"); - if (!fp) { - return -ENOENT; - } - len = fread(uuid, 1, LTTNG_UST_UUID_STR_LEN - 1, fp); - if (len < LTTNG_UST_UUID_STR_LEN - 1) { - ret = -EINVAL; + uint64_t frequency = 0; + lttng_ust_clock_freq_function get_freq_cb; + + if (lttng_ust_trace_clock_get_freq_cb(&get_freq_cb)) { goto end; } - uuid[LTTNG_UST_UUID_STR_LEN - 1] = '\0'; -end: - fclose(fp); - return ret; -} - -static __inline__ -const char *trace_clock_name_monotonic(void) -{ - return "monotonic"; -} -static __inline__ -const char *trace_clock_description_monotonic(void) -{ - return "Monotonic Clock"; + frequency = get_freq_cb(); +end: + return frequency; } static __inline__ -uint64_t trace_clock_read64(void) +int trace_clock_uuid(char *uuid) { - struct lttng_trace_clock *ltc = CMM_LOAD_SHARED(lttng_trace_clock); + int ret; + lttng_ust_clock_uuid_function get_uuid_cb; - if (caa_likely(!ltc)) { - return trace_clock_read64_monotonic(); - } else { - cmm_read_barrier_depends(); /* load ltc before content */ - return ltc->read64(); + if (lttng_ust_trace_clock_get_uuid_cb(&get_uuid_cb)) { + ret = -EINVAL; + goto end; } -} - -static __inline__ -uint64_t trace_clock_freq(void) -{ - struct lttng_trace_clock *ltc = CMM_LOAD_SHARED(lttng_trace_clock); - if (!ltc) { - return trace_clock_freq_monotonic(); - } else { - cmm_read_barrier_depends(); /* load ltc before content */ - return ltc->freq(); - } -} + ret = get_uuid_cb(uuid); +end: + return ret; -static __inline__ -int trace_clock_uuid(char *uuid) -{ - struct lttng_trace_clock *ltc = CMM_LOAD_SHARED(lttng_trace_clock); - - cmm_read_barrier_depends(); /* load ltc before content */ - /* Use default UUID cb when NULL */ - if (!ltc || !ltc->uuid) { - return trace_clock_uuid_monotonic(uuid); - } else { - return ltc->uuid(uuid); - } } static __inline__ const char *trace_clock_name(void) { - struct lttng_trace_clock *ltc = CMM_LOAD_SHARED(lttng_trace_clock); + const char *name; + lttng_ust_clock_name_function get_name_cb; - if (!ltc) { - return trace_clock_name_monotonic(); - } else { - cmm_read_barrier_depends(); /* load ltc before content */ - return ltc->name(); + if (lttng_ust_trace_clock_get_name_cb(&get_name_cb)) { + name = NULL; + goto end; } + + name = get_name_cb(); +end: + return name; } static __inline__ const char *trace_clock_description(void) { - struct lttng_trace_clock *ltc = CMM_LOAD_SHARED(lttng_trace_clock); + const char *description; + lttng_ust_clock_description_function get_description_cb; - if (!ltc) { - return trace_clock_description_monotonic(); - } else { - cmm_read_barrier_depends(); /* load ltc before content */ - return ltc->description(); + if (lttng_ust_trace_clock_get_description_cb(&get_description_cb)) { + description = NULL; + goto end; } + + description = get_description_cb(); +end: + return description; } #endif /* _UST_CLOCK_H */