Merging upstream version 1.37.1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

7 files changed, 153 insertions, 116 deletions

diff --git a/libnetdata/dictionary/dictionary.c b/libnetdata/dictionary/dictionary.c
index f03da25ab..0277e067f 100644
--- a/libnetdata/dictionary/dictionary.c
+++ b/libnetdata/dictionary/dictionary.c
@@ -3,10 +3,9 @@
 #define DICTIONARY_INTERNALS
 
 #include "../libnetdata.h"
-#include <Judy.h>
 
 // runtime flags of the dictionary - must be checked with atomics
-typedef enum {
+typedef enum __attribute__ ((__packed__)) {
     DICT_FLAG_NONE                  = 0,
     DICT_FLAG_DESTROYED             = (1 << 0), // this dictionary has been destroyed
 } DICT_FLAGS;
@@ -23,14 +22,14 @@ typedef enum {
 #define is_view_dictionary(dict) ((dict)->master)
 #define is_master_dictionary(dict) (!is_view_dictionary(dict))
 
-typedef enum item_options {
+typedef enum __attribute__ ((__packed__)) item_options {
     ITEM_OPTION_NONE            = 0,
     ITEM_OPTION_ALLOCATED_NAME  = (1 << 0), // the name pointer is a STRING
 
     // IMPORTANT: This is 1-bit - to add more change ITEM_OPTIONS_BITS
 } ITEM_OPTIONS;
 
-typedef enum item_flags {
+typedef enum __attribute__ ((__packed__)) item_flags {
     ITEM_FLAG_NONE              = 0,
     ITEM_FLAG_DELETED           = (1 << 0), // this item is marked deleted, so it is not available for traversal (deleted from the index too)
     ITEM_FLAG_BEING_CREATED     = (1 << 1), // this item is currently being created - this flag is removed when construction finishes
@@ -623,7 +622,7 @@ static void dictionary_execute_delete_callback(DICTIONARY *dict, DICTIONARY_ITEM
     if(likely(!dict->hooks || !dict->hooks->del_callback))
         return;
 
-    // We may execute the delete callback on items deleted from a view,
+    // We may execute delete callback on items deleted from a view,
     // because we may have references to it, after the master is gone
     // so, the shared structure will remain until the last reference is released.
 
@@ -782,7 +781,7 @@ static void garbage_collect_pending_deletes(DICTIONARY *dict) {
     while(item) {
         examined++;
 
-        // this will cleanup
+        // this will clean up
         item_next = item->next;
         int rc = item_check_and_acquire_advanced(dict, item, is_view);
 
@@ -882,7 +881,7 @@ static void item_acquire(DICTIONARY *dict, DICTIONARY_ITEM *item) {
 
 static void item_release(DICTIONARY *dict, DICTIONARY_ITEM *item) {
     // this function may be called without any lock on the dictionary
-    // or even when someone else has write lock on the dictionary
+    // or even when someone else has 'write' lock on the dictionary
 
     bool is_deleted;
     REFCOUNT refcount;
@@ -934,11 +933,11 @@ static int item_check_and_acquire_advanced(DICTIONARY *dict, DICTIONARY_ITEM *it
 
     int ret = RC_ITEM_OK;
 
+    refcount = DICTIONARY_ITEM_REFCOUNT_GET(dict, item);
+
     do {
         spins++;
 
-        refcount = DICTIONARY_ITEM_REFCOUNT_GET(dict, item);
-
         if(refcount < 0) {
             // we can't use this item
             ret = RC_ITEM_IS_CURRENTLY_BEING_DELETED;
@@ -953,8 +952,7 @@ static int item_check_and_acquire_advanced(DICTIONARY *dict, DICTIONARY_ITEM *it
 
         desired = refcount + 1;
 
-    } while(!__atomic_compare_exchange_n(&item->refcount, &refcount, desired,
-                                          false, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST));
+    } while(!__atomic_compare_exchange_n(&item->refcount, &refcount, desired, false, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST));
 
     // if ret == ITEM_OK, we acquired the item
 
@@ -971,7 +969,7 @@ static int item_check_and_acquire_advanced(DICTIONARY *dict, DICTIONARY_ITEM *it
                 else
                     pointer_del(dict, item);
 
-                // mark it in our dictionary as deleted too
+                // mark it in our dictionary as deleted too,
                 // this is safe to be done here, because we have got
                 // a reference counter on item
                 dict_item_set_deleted(dict, item);
@@ -1013,11 +1011,11 @@ static inline int item_is_not_referenced_and_can_be_removed_advanced(DICTIONARY
 
     int ret = RC_ITEM_OK;
 
+    refcount = DICTIONARY_ITEM_REFCOUNT_GET(dict, item);
+
     do {
         spins++;
 
-        refcount = DICTIONARY_ITEM_REFCOUNT_GET(dict, item);
-
         if(refcount < 0) {
             // we can't use this item
             ret = RC_ITEM_IS_CURRENTLY_BEING_DELETED;
@@ -1035,8 +1033,7 @@ static inline int item_is_not_referenced_and_can_be_removed_advanced(DICTIONARY
             ret = RC_ITEM_IS_CURRENTLY_BEING_CREATED;
             break;
         }
-    } while(!__atomic_compare_exchange_n(&item->refcount, &refcount, desired,
-                                                         false, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST));
+    } while(!__atomic_compare_exchange_n(&item->refcount, &refcount, desired, false, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST));
 
 #ifdef NETDATA_INTERNAL_CHECKS
     if(ret == RC_ITEM_OK)
@@ -1055,8 +1052,7 @@ static inline bool item_shared_release_and_check_if_it_can_be_freed(DICTIONARY *
     // if we can set refcount to REFCOUNT_DELETING, we can delete this item
 
     REFCOUNT links = __atomic_sub_fetch(&item->shared->links, 1, __ATOMIC_SEQ_CST);
-    if(links == 0 && __atomic_compare_exchange_n(&item->shared->links, &links, REFCOUNT_DELETING,
-                                                     false, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST)) {
+    if(links == 0 && __atomic_compare_exchange_n(&item->shared->links, &links, REFCOUNT_DELETING, false, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST)) {
 
         // we can delete it
         return true;
@@ -1430,16 +1426,16 @@ static void dict_item_shared_set_deleted(DICTIONARY *dict, DICTIONARY_ITEM *item
 static bool dict_item_set_deleted(DICTIONARY *dict, DICTIONARY_ITEM *item) {
     ITEM_FLAGS expected, desired;
 
+    expected = __atomic_load_n(&item->flags, __ATOMIC_SEQ_CST);
+
     do {
-        expected = __atomic_load_n(&item->flags, __ATOMIC_SEQ_CST);
 
         if (expected & ITEM_FLAG_DELETED)
             return false;
 
         desired = expected | ITEM_FLAG_DELETED;
 
-    } while(!__atomic_compare_exchange_n(&item->flags, &expected, desired,
-                                         false, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST));
+    } while(!__atomic_compare_exchange_n(&item->flags, &expected, desired, false, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST));
 
     DICTIONARY_ENTRIES_MINUS1(dict);
     return true;
@@ -1474,7 +1470,7 @@ static inline void dict_item_free_or_mark_deleted(DICTIONARY *dict, DICTIONARY_I
 }
 
 // this is used by traversal functions to remove the current item
-// if it is deleted and it has zero references. This will eliminate
+// if it is deleted, and it has zero references. This will eliminate
 // the need for the garbage collector to kick-in later.
 // Most deletions happen during traversal, so this is a nice hack
 // to speed up everything!
@@ -1601,7 +1597,7 @@ static DICTIONARY_ITEM *dict_item_add_or_reset_value_and_acquire(DICTIONARY *dic
             hashtable_inserted_item_unsafe(dict, item);
 
             // unlock the index lock, before we add it to the linked list
-            // DONT DO IT THE OTHER WAY AROUND - DO NOT CROSS THE LOCKS!
+            // DON'T DO IT THE OTHER WAY AROUND - DO NOT CROSS THE LOCKS!
             dictionary_index_wrlock_unlock(dict);
 
             item_linked_list_add(dict, item);
diff --git a/libnetdata/procfile/procfile.c b/libnetdata/procfile/procfile.c
index b4ca025ec..eb04316c3 100644
--- a/libnetdata/procfile/procfile.c
+++ b/libnetdata/procfile/procfile.c
@@ -22,16 +22,21 @@ size_t procfile_max_allocation = PROCFILE_INCREMENT_BUFFER;
 // ----------------------------------------------------------------------------
 
 char *procfile_filename(procfile *ff) {
-    if(ff->filename[0]) return ff->filename;
+    if(ff->filename)
+        return ff->filename;
 
+    char filename[FILENAME_MAX + 1];
     char buffer[FILENAME_MAX + 1];
     snprintfz(buffer, FILENAME_MAX, "/proc/self/fd/%d", ff->fd);
 
-    ssize_t l = readlink(buffer, ff->filename, FILENAME_MAX);
+    ssize_t l = readlink(buffer, filename, FILENAME_MAX);
     if(unlikely(l == -1))
-        snprintfz(ff->filename, FILENAME_MAX, "unknown filename for fd %d", ff->fd);
+        snprintfz(filename, FILENAME_MAX, "unknown filename for fd %d", ff->fd);
     else
-        ff->filename[l] = '\0';
+        filename[l] = '\0';
+
+
+    ff->filename = strdupz(filename);
 
     // on non-linux systems, something like this will be needed
     // fcntl(ff->fd, F_GETPATH, ff->filename)
@@ -141,8 +146,9 @@ void procfile_close(procfile *ff) {
 
     debug(D_PROCFILE, PF_PREFIX ": Closing file '%s'", procfile_filename(ff));
 
-    if(likely(ff->lines)) procfile_lines_free(ff->lines);
-    if(likely(ff->words)) procfile_words_free(ff->words);
+    freez(ff->filename);
+    procfile_lines_free(ff->lines);
+    procfile_words_free(ff->words);
 
     if(likely(ff->fd != -1)) close(ff->fd);
     freez(ff);
@@ -319,40 +325,31 @@ procfile *procfile_readall(procfile *ff) {
     return ff;
 }
 
-NOINLINE
-static void procfile_set_separators(procfile *ff, const char *separators) {
-    static PF_CHAR_TYPE def[256];
-    static char initialized = 0;
-
-    if(unlikely(!initialized)) {
-        // this is thread safe
-        // if initialized is zero, multiple threads may be executing
-        // this code at the same time, setting in def[] the exact same values
-        int i = 256;
-        while(i--) {
-            if(unlikely(i == '\n' || i == '\r'))
-                def[i] = PF_CHAR_IS_NEWLINE;
+static PF_CHAR_TYPE procfile_default_separators[256];
+__attribute__((constructor)) void procfile_initialize_default_separators(void) {
+    int i = 256;
+    while(i--) {
+        if(unlikely(i == '\n' || i == '\r'))
+            procfile_default_separators[i] = PF_CHAR_IS_NEWLINE;
 
-            else if(unlikely(isspace(i) || !isprint(i)))
-                def[i] = PF_CHAR_IS_SEPARATOR;
+        else if(unlikely(isspace(i) || !isprint(i)))
+            procfile_default_separators[i] = PF_CHAR_IS_SEPARATOR;
 
-            else
-                def[i] = PF_CHAR_IS_WORD;
-        }
-
-        initialized = 1;
+        else
+            procfile_default_separators[i] = PF_CHAR_IS_WORD;
     }
+}
 
-    // copy the default
-    PF_CHAR_TYPE *ffs = ff->separators, *ffd = def, *ffe = &def[256];
-    while(ffd != ffe)
-        *ffs++ = *ffd++;
-
+NOINLINE
+static void procfile_set_separators(procfile *ff, const char *separators) {
     // set the separators
     if(unlikely(!separators))
         separators = " \t=|";
 
-    ffs = ff->separators;
+    // copy the default
+    memcpy(ff->separators, procfile_default_separators, 256 * sizeof(PF_CHAR_TYPE));
+
+    PF_CHAR_TYPE *ffs = ff->separators;
     const char *s = separators;
     while(*s)
         ffs[(int)*s++] = PF_CHAR_IS_SEPARATOR;
@@ -416,8 +413,7 @@ procfile *procfile_open(const char *filename, const char *separators, uint32_t f
     procfile *ff = mallocz(sizeof(procfile) + size);
 
     //strncpyz(ff->filename, filename, FILENAME_MAX);
-    ff->filename[0] = '\0';
-
+    ff->filename = NULL;
     ff->fd = fd;
     ff->size = size;
     ff->len = 0;
@@ -449,7 +445,8 @@ procfile *procfile_reopen(procfile *ff, const char *filename, const char *separa
     // info("PROCFILE: opened '%s' on fd %d", filename, ff->fd);
 
     //strncpyz(ff->filename, filename, FILENAME_MAX);
-    ff->filename[0] = '\0';
+    freez(ff->filename);
+    ff->filename = NULL;
     ff->flags = flags;
 
     // do not do the separators again if NULL is given
diff --git a/libnetdata/procfile/procfile.h b/libnetdata/procfile/procfile.h
index 5d45e4028..cae4ad484 100644
--- a/libnetdata/procfile/procfile.h
+++ b/libnetdata/procfile/procfile.h
@@ -37,7 +37,7 @@ typedef struct {
 #define PROCFILE_FLAG_DEFAULT             0x00000000
 #define PROCFILE_FLAG_NO_ERROR_ON_FILE_IO 0x00000001
 
-typedef enum procfile_separator {
+typedef enum __attribute__ ((__packed__)) procfile_separator {
     PF_CHAR_IS_SEPARATOR,
     PF_CHAR_IS_NEWLINE,
     PF_CHAR_IS_WORD,
@@ -46,17 +46,16 @@ typedef enum procfile_separator {
     PF_CHAR_IS_CLOSE
 } PF_CHAR_TYPE;
 
-typedef struct {
-    char filename[FILENAME_MAX + 1]; // not populated until profile_filename() is called
-
+typedef struct procfile {
+    char *filename;                 // not populated until procfile_filename() is called
     uint32_t flags;
-    int fd;               // the file descriptor
-    size_t len;           // the bytes we have placed into data
-    size_t size;          // the bytes we have allocated for data
+    int fd;                         // the file descriptor
+    size_t len;                     // the bytes we have placed into data
+    size_t size;                    // the bytes we have allocated for data
     pflines *lines;
     pfwords *words;
     PF_CHAR_TYPE separators[256];
-    char data[];          // allocated buffer to keep file contents
+    char data[];                    // allocated buffer to keep file contents
 } procfile;
 
 // close the proc file and free all related memory
diff --git a/libnetdata/socket/security.c b/libnetdata/socket/security.c
index f7b44049b..88b3f6d93 100644
--- a/libnetdata/socket/security.c
+++ b/libnetdata/socket/security.c
@@ -204,31 +204,43 @@ static SSL_CTX * security_initialize_openssl_server() {
  *      NETDATA_SSL_CONTEXT_EXPORTING - Starts the OpenTSDB context
  */
 void security_start_ssl(int selector) {
+    static SPINLOCK sp = NETDATA_SPINLOCK_INITIALIZER;
+    netdata_spinlock_lock(&sp);
+
     switch (selector) {
         case NETDATA_SSL_CONTEXT_SERVER: {
-            struct stat statbuf;
-            if (stat(netdata_ssl_security_key, &statbuf) || stat(netdata_ssl_security_cert, &statbuf)) {
-                info("To use encryption it is necessary to set \"ssl certificate\" and \"ssl key\" in [web] !\n");
-                return;
+            if(!netdata_ssl_srv_ctx) {
+                struct stat statbuf;
+                if (stat(netdata_ssl_security_key, &statbuf) || stat(netdata_ssl_security_cert, &statbuf))
+                    info("To use encryption it is necessary to set \"ssl certificate\" and \"ssl key\" in [web] !\n");
+                else {
+                    netdata_ssl_srv_ctx = security_initialize_openssl_server();
+                    SSL_CTX_set_mode(netdata_ssl_srv_ctx, SSL_MODE_ENABLE_PARTIAL_WRITE);
+                }
             }
-
-            netdata_ssl_srv_ctx =  security_initialize_openssl_server();
-            SSL_CTX_set_mode(netdata_ssl_srv_ctx, SSL_MODE_ENABLE_PARTIAL_WRITE);
             break;
         }
+
         case NETDATA_SSL_CONTEXT_STREAMING: {
-            netdata_ssl_client_ctx = security_initialize_openssl_client();
-            //This is necessary for the stream, because it is working sometimes with nonblock socket.
-            //It returns the bitmask after to change, there is not any description of errors in the documentation
-            SSL_CTX_set_mode(
-                netdata_ssl_client_ctx, SSL_MODE_ENABLE_PARTIAL_WRITE |SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER |SSL_MODE_AUTO_RETRY);
+            if(!netdata_ssl_client_ctx) {
+                netdata_ssl_client_ctx = security_initialize_openssl_client();
+                //This is necessary for the stream, because it is working sometimes with nonblock socket.
+                //It returns the bitmask after to change, there is not any description of errors in the documentation
+                SSL_CTX_set_mode(netdata_ssl_client_ctx,
+                                 SSL_MODE_ENABLE_PARTIAL_WRITE | SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER |
+                                 SSL_MODE_AUTO_RETRY);
+            }
             break;
         }
+
         case NETDATA_SSL_CONTEXT_EXPORTING: {
-            netdata_ssl_exporting_ctx = security_initialize_openssl_client();
+            if(!netdata_ssl_exporting_ctx)
+                netdata_ssl_exporting_ctx = security_initialize_openssl_client();
             break;
         }
     }
+
+    netdata_spinlock_unlock(&sp);
 }
 
 /**
diff --git a/libnetdata/string/string.c b/libnetdata/string/string.c
index a3f74b4ef..d2db8aab4 100644
--- a/libnetdata/string/string.c
+++ b/libnetdata/string/string.c
@@ -71,11 +71,12 @@ void string_statistics(size_t *inserts, size_t *deletes, size_t *searches, size_
 
 static inline bool string_entry_check_and_acquire(STRING *se) {
     REFCOUNT expected, desired, count = 0;
+
+    expected = __atomic_load_n(&se->refcount, __ATOMIC_SEQ_CST);
+
     do {
         count++;
 
-        expected = __atomic_load_n(&se->refcount, __ATOMIC_SEQ_CST);
-
         if(expected <= 0) {
             // We cannot use this.
             // The reference counter reached value zero,
@@ -85,8 +86,8 @@ static inline bool string_entry_check_and_acquire(STRING *se) {
         }
 
         desired = expected + 1;
-    }
-    while(!__atomic_compare_exchange_n(&se->refcount, &expected, desired, false, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST));
+
+    } while(!__atomic_compare_exchange_n(&se->refcount, &expected, desired, false, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST));
 
     string_internal_stats_add(spins, count - 1);
 
diff --git a/libnetdata/worker_utilization/worker_utilization.c b/libnetdata/worker_utilization/worker_utilization.c
index 14b8926e0..afaff209b 100644
--- a/libnetdata/worker_utilization/worker_utilization.c
+++ b/libnetdata/worker_utilization/worker_utilization.c
@@ -44,35 +44,55 @@ struct worker {
     struct worker *prev;
 };
 
-static netdata_mutex_t workers_base_lock = NETDATA_MUTEX_INITIALIZER;
-static __thread struct worker *worker = NULL;
-static Pvoid_t workers_per_workname_JudyHS_array = NULL;
+struct workers_workname {                           // this is what we add to JudyHS
+    SPINLOCK spinlock;
+    struct worker *base;
+};
+
+static struct workers_globals {
+    SPINLOCK spinlock;
+    Pvoid_t worknames_JudyHS;
+
+} workers_globals = {                               // workers globals, the base of all worknames
+        .spinlock = NETDATA_SPINLOCK_INITIALIZER,   // a lock for the worknames index
+        .worknames_JudyHS = NULL,                   // the worknames index
+};
 
-void worker_register(const char *workname) {
+static __thread struct worker *worker = NULL; // the current thread worker
+
+void worker_register(const char *name) {
     if(unlikely(worker)) return;
 
     worker = callocz(1, sizeof(struct worker));
     worker->pid = gettid();
     worker->tag = strdupz(netdata_thread_tag());
-    worker->workname = strdupz(workname);
+    worker->workname = strdupz(name);
 
     usec_t now = now_monotonic_usec();
     worker->statistics_last_checkpoint = now;
     worker->last_action_timestamp = now;
     worker->last_action = WORKER_IDLE;
 
-    size_t workname_size = strlen(workname) + 1;
-    netdata_mutex_lock(&workers_base_lock);
+    size_t name_size = strlen(name) + 1;
+    netdata_spinlock_lock(&workers_globals.spinlock);
 
-    Pvoid_t *PValue = JudyHSGet(workers_per_workname_JudyHS_array, (void *)workname, workname_size);
+    Pvoid_t *PValue = JudyHSGet(workers_globals.worknames_JudyHS, (void *)name, name_size);
     if(!PValue)
-        PValue = JudyHSIns(&workers_per_workname_JudyHS_array, (void *)workname, workname_size, PJE0);
+        PValue = JudyHSIns(&workers_globals.worknames_JudyHS, (void *)name, name_size, PJE0);
+
+    struct workers_workname *workname = *PValue;
+    if(!workname) {
+        workname = mallocz(sizeof(struct workers_workname));
+        workname->spinlock = NETDATA_SPINLOCK_INITIALIZER;
+        workname->base = NULL;
+        *PValue = workname;
+    }
 
-    struct worker *base = *PValue;
-    DOUBLE_LINKED_LIST_APPEND_UNSAFE(base, worker, prev, next);
-    *PValue = base;
+    netdata_spinlock_lock(&workname->spinlock);
+    DOUBLE_LINKED_LIST_APPEND_UNSAFE(workname->base, worker, prev, next);
+    netdata_spinlock_unlock(&workname->spinlock);
 
-    netdata_mutex_unlock(&workers_base_lock);
+    netdata_spinlock_unlock(&workers_globals.spinlock);
 }
 
 void worker_register_job_custom_metric(size_t job_id, const char *name, const char *units, WORKER_METRIC_TYPE type) {
@@ -105,17 +125,20 @@ void worker_unregister(void) {
     if(unlikely(!worker)) return;
 
     size_t workname_size = strlen(worker->workname) + 1;
-    netdata_mutex_lock(&workers_base_lock);
-    Pvoid_t *PValue = JudyHSGet(workers_per_workname_JudyHS_array, (void *)worker->workname, workname_size);
+    netdata_spinlock_lock(&workers_globals.spinlock);
+    Pvoid_t *PValue = JudyHSGet(workers_globals.worknames_JudyHS, (void *)worker->workname, workname_size);
     if(PValue) {
-        struct worker *base = *PValue;
-        DOUBLE_LINKED_LIST_REMOVE_UNSAFE(base, worker, prev, next);
-        *PValue = base;
-
-        if(!base)
-            JudyHSDel(&workers_per_workname_JudyHS_array, (void *)worker->workname, workname_size, PJE0);
+        struct workers_workname *workname = *PValue;
+        netdata_spinlock_lock(&workname->spinlock);
+        DOUBLE_LINKED_LIST_REMOVE_UNSAFE(workname->base, worker, prev, next);
+        netdata_spinlock_unlock(&workname->spinlock);
+
+        if(!workname->base) {
+            JudyHSDel(&workers_globals.worknames_JudyHS, (void *) worker->workname, workname_size, PJE0);
+            freez(workname);
+        }
     }
-    netdata_mutex_unlock(&workers_base_lock);
+    netdata_spinlock_unlock(&workers_globals.spinlock);
 
     for(int i  = 0; i < WORKER_UTILIZATION_MAX_JOB_TYPES ;i++) {
         string_freez(worker->per_job_type[i].name);
@@ -187,7 +210,7 @@ void worker_set_metric(size_t job_id, NETDATA_DOUBLE value) {
 
 // statistics interface
 
-void workers_foreach(const char *workname, void (*callback)(
+void workers_foreach(const char *name, void (*callback)(
                                                void *data
                                                , pid_t pid
                                                , const char *thread_tag
@@ -203,18 +226,27 @@ void workers_foreach(const char *workname, void (*callback)(
                                                , NETDATA_DOUBLE *job_custom_values
                                                )
                                                , void *data) {
-    netdata_mutex_lock(&workers_base_lock);
+    netdata_spinlock_lock(&workers_globals.spinlock);
     usec_t busy_time, delta;
     size_t i, jobs_started, jobs_running;
 
-    size_t workname_size = strlen(workname) + 1;
-    struct worker *base = NULL;
-    Pvoid_t *PValue = JudyHSGet(workers_per_workname_JudyHS_array, (void *)workname, workname_size);
-    if(PValue)
-        base = *PValue;
+    size_t workname_size = strlen(name) + 1;
+    struct workers_workname *workname;
+    Pvoid_t *PValue = JudyHSGet(workers_globals.worknames_JudyHS, (void *)name, workname_size);
+    if(PValue) {
+        workname = *PValue;
+        netdata_spinlock_lock(&workname->spinlock);
+    }
+    else
+        workname = NULL;
+
+    netdata_spinlock_unlock(&workers_globals.spinlock);
+
+    if(!workname)
+        return;
 
     struct worker *p;
-    DOUBLE_LINKED_LIST_FOREACH_FORWARD(base, p, prev, next) {
+    DOUBLE_LINKED_LIST_FOREACH_FORWARD(workname->base, p, prev, next) {
         usec_t now = now_monotonic_usec();
 
         // find per job type statistics
@@ -326,5 +358,5 @@ void workers_foreach(const char *workname, void (*callback)(
                  );
     }
 
-    netdata_mutex_unlock(&workers_base_lock);
+    netdata_spinlock_unlock(&workname->spinlock);
 }
diff --git a/libnetdata/worker_utilization/worker_utilization.h b/libnetdata/worker_utilization/worker_utilization.h
index 04d24f1f7..f1412e6b4 100644
--- a/libnetdata/worker_utilization/worker_utilization.h
+++ b/libnetdata/worker_utilization/worker_utilization.h
@@ -15,7 +15,7 @@ typedef enum {
     WORKER_METRIC_INCREMENTAL_TOTAL = 4,
 } WORKER_METRIC_TYPE;
 
-void worker_register(const char *workname);
+void worker_register(const char *name);
 void worker_register_job_name(size_t job_id, const char *name);
 void worker_register_job_custom_metric(size_t job_id, const char *name, const char *units, WORKER_METRIC_TYPE type);
 void worker_unregister(void);
@@ -26,7 +26,7 @@ void worker_set_metric(size_t job_id, NETDATA_DOUBLE value);
 
 // statistics interface
 
-void workers_foreach(const char *workname, void (*callback)(
+void workers_foreach(const char *name, void (*callback)(
                                                       void *data
                                                       , pid_t pid
                                                       , const char *thread_tag