Line data    Source code

       1             : /*   SPDX-License-Identifier: BSD-3-Clause
       2             :  *   Copyright (c) 2022, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
       3             :  */
       4             : 
       5             : #include "spdk/stdinc.h"
       6             : #include "spdk/string.h"
       7             : #include "spdk/thread.h"
       8             : #include "spdk/util.h"
       9             : #include "spdk/log.h"
      10             : 
      11             : struct spdk_deprecation {
      12             :         const char tag[64];
      13             :         const char desc[64];
      14             :         const char remove[16];
      15             :         TAILQ_ENTRY(spdk_deprecation) link;
      16             :         uint64_t hits;
      17             :         /* How often (nanoseconds) to log. */
      18             :         uint64_t interval;
      19             :         /* How many messages were not logged due to rate limiting */
      20             :         uint32_t deferred;
      21             :         /* CLOCK_MONOTONIC microseconds since g_deprecation_epoch when last warning was logged */
      22             :         uint64_t last_log;
      23             : };
      24             : 
      25             : static TAILQ_HEAD(, spdk_deprecation) g_deprecations = TAILQ_HEAD_INITIALIZER(g_deprecations);
      26             : static struct timespec g_deprecation_epoch;
      27             : 
      28             : static void
      29             : __attribute__((constructor))
      30           6 : deprecation_init(void)
      31             : {
      32           6 :         clock_gettime(CLOCK_MONOTONIC, &g_deprecation_epoch);
      33           6 : }
      34             : 
      35             : static inline uint64_t
      36           7 : get_ns_since_epoch(void)
      37             : {
      38             :         struct timespec now;
      39             : 
      40           7 :         clock_gettime(CLOCK_MONOTONIC, &now);
      41           7 :         return (now.tv_sec - g_deprecation_epoch.tv_sec) * SPDK_SEC_TO_NSEC +
      42           7 :                now.tv_nsec - g_deprecation_epoch.tv_nsec;
      43             : }
      44             : 
      45             : int
      46          11 : spdk_log_deprecation_register(const char *tag, const char *description, const char *remove_release,
      47             :                               uint32_t rate_limit_seconds, struct spdk_deprecation **depp)
      48             : {
      49             :         struct spdk_deprecation *dep;
      50             : 
      51          11 :         assert(strnlen(tag, sizeof(dep->tag)) < sizeof(dep->tag));
      52          11 :         assert(strnlen(description, sizeof(dep->desc)) < sizeof(dep->desc));
      53          11 :         assert(strnlen(remove_release, sizeof(dep->remove)) < sizeof(dep->remove));
      54             : 
      55          11 :         dep = calloc(1, sizeof(*dep));
      56          11 :         if (dep == NULL) {
      57           0 :                 return -ENOMEM;
      58             :         }
      59             : 
      60          11 :         snprintf((char *)dep->tag, sizeof(dep->tag), "%s", tag);
      61          11 :         snprintf((char *)dep->desc, sizeof(dep->desc), "%s", description);
      62          11 :         snprintf((char *)dep->remove, sizeof(dep->remove), "%s", remove_release);
      63          11 :         dep->interval = rate_limit_seconds * SPDK_SEC_TO_NSEC;
      64             : 
      65          11 :         TAILQ_INSERT_TAIL(&g_deprecations, dep, link);
      66          11 :         *depp = dep;
      67          11 :         return 0;
      68             : }
      69             : 
      70             : /*
      71             :  * There is potential for races between pthreads leading to over or under reporting of times that
      72             :  * deprecated code was hit. If this function is called in a hot path where that is likely, we care
      73             :  * more about performance than accuracy of the error counts. The important thing is that at least
      74             :  * one of the racing updates the hits counter to non-zero and the warning is logged at least once.
      75             :  */
      76             : void
      77           7 : spdk_log_deprecated(struct spdk_deprecation *dep, const char *file, uint32_t line, const char *func)
      78             : {
      79           7 :         uint64_t now = get_ns_since_epoch();
      80             : 
      81           7 :         if (dep == NULL) {
      82           0 :                 SPDK_ERRLOG("NULL deprecation passed from %s:%u:%s\n", file, line, func);
      83           0 :                 assert(false);
      84             :                 return;
      85             :         }
      86             : 
      87           7 :         dep->hits++;
      88             : 
      89           7 :         if (dep->interval != 0) {
      90           3 :                 if (dep->last_log != 0 && now < dep->last_log + dep->interval) {
      91           1 :                         dep->deferred++;
      92           1 :                         return;
      93             :                 }
      94             :         }
      95             : 
      96           6 :         dep->last_log = now;
      97             : 
      98           6 :         spdk_log(SPDK_LOG_WARN, file, line, func, "%s: deprecated feature %s to be removed in %s\n",
      99           6 :                  dep->tag, dep->desc, dep->remove);
     100           6 :         if (dep->deferred != 0) {
     101           1 :                 SPDK_WARNLOG("%s: %u messages suppressed\n", dep->tag, dep->deferred);
     102           1 :                 dep->deferred = 0;
     103             :         }
     104             : }
     105             : 
     106             : int
     107           1 : spdk_log_for_each_deprecation(void *ctx, spdk_log_for_each_deprecation_fn fn)
     108             : {
     109             :         struct spdk_deprecation *dep;
     110           1 :         int rc = 0;
     111             : 
     112           4 :         TAILQ_FOREACH(dep, &g_deprecations, link) {
     113           3 :                 rc = fn(ctx, dep);
     114           3 :                 if (rc != 0) {
     115           0 :                         break;
     116             :                 }
     117             :         }
     118             : 
     119           1 :         return rc;
     120             : }
     121             : 
     122             : const char *
     123           3 : spdk_deprecation_get_tag(const struct spdk_deprecation *deprecation)
     124             : {
     125           3 :         return deprecation->tag;
     126             : }
     127             : 
     128             : const char *
     129           3 : spdk_deprecation_get_description(const struct spdk_deprecation *deprecation)
     130             : {
     131           3 :         return deprecation->desc;
     132             : }
     133             : 
     134             : const char *
     135           3 : spdk_deprecation_get_remove_release(const struct spdk_deprecation *deprecation)
     136             : {
     137           3 :         return deprecation->remove;
     138             : }
     139             : 
     140             : uint64_t
     141           3 : spdk_deprecation_get_hits(const struct spdk_deprecation *deprecation)
     142             : {
     143           3 :         return deprecation->hits;
     144             : }