From c8bae7493d2f2910b57f13ded012e86bdcfb0532 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 16:47:53 +0200 Subject: Adding upstream version 1:2.39.2. Signed-off-by: Daniel Baumann --- trace2/tr2_tls.c | 193 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 193 insertions(+) create mode 100644 trace2/tr2_tls.c (limited to 'trace2/tr2_tls.c') diff --git a/trace2/tr2_tls.c b/trace2/tr2_tls.c new file mode 100644 index 0000000..04900bb --- /dev/null +++ b/trace2/tr2_tls.c @@ -0,0 +1,193 @@ +#include "cache.h" +#include "thread-utils.h" +#include "trace2/tr2_tls.h" + +/* + * Initialize size of the thread stack for nested regions. + * This is used to store nested region start times. Note that + * this stack is per-thread and not per-trace-key. + */ +#define TR2_REGION_NESTING_INITIAL_SIZE (100) + +static struct tr2tls_thread_ctx *tr2tls_thread_main; +static uint64_t tr2tls_us_start_process; + +static pthread_mutex_t tr2tls_mutex; +static pthread_key_t tr2tls_key; + +static int tr2_next_thread_id; /* modify under lock */ + +void tr2tls_start_process_clock(void) +{ + if (tr2tls_us_start_process) + return; + + /* + * Keep the absolute start time of the process (i.e. the main + * process) in a fixed variable since other threads need to + * access it. This allows them to do that without a lock on + * main thread's array data (because of reallocs). + */ + tr2tls_us_start_process = getnanotime() / 1000; +} + +struct tr2tls_thread_ctx *tr2tls_create_self(const char *thread_base_name, + uint64_t us_thread_start) +{ + struct tr2tls_thread_ctx *ctx = xcalloc(1, sizeof(*ctx)); + struct strbuf buf = STRBUF_INIT; + + /* + * Implicitly "tr2tls_push_self()" to capture the thread's start + * time in array_us_start[0]. For the main thread this gives us the + * application run time. + */ + ctx->alloc = TR2_REGION_NESTING_INITIAL_SIZE; + ctx->array_us_start = (uint64_t *)xcalloc(ctx->alloc, sizeof(uint64_t)); + ctx->array_us_start[ctx->nr_open_regions++] = us_thread_start; + + ctx->thread_id = tr2tls_locked_increment(&tr2_next_thread_id); + + strbuf_init(&buf, 0); + if (ctx->thread_id) + strbuf_addf(&buf, "th%02d:", ctx->thread_id); + strbuf_addstr(&buf, thread_base_name); + if (buf.len > TR2_MAX_THREAD_NAME) + strbuf_setlen(&buf, TR2_MAX_THREAD_NAME); + ctx->thread_name = strbuf_detach(&buf, NULL); + + pthread_setspecific(tr2tls_key, ctx); + + return ctx; +} + +struct tr2tls_thread_ctx *tr2tls_get_self(void) +{ + struct tr2tls_thread_ctx *ctx; + + if (!HAVE_THREADS) + return tr2tls_thread_main; + + ctx = pthread_getspecific(tr2tls_key); + + /* + * If the current thread's thread-proc did not call + * trace2_thread_start(), then the thread will not have any + * thread-local storage. Create it now and silently continue. + */ + if (!ctx) + ctx = tr2tls_create_self("unknown", getnanotime() / 1000); + + return ctx; +} + +int tr2tls_is_main_thread(void) +{ + if (!HAVE_THREADS) + return 1; + + return pthread_getspecific(tr2tls_key) == tr2tls_thread_main; +} + +void tr2tls_unset_self(void) +{ + struct tr2tls_thread_ctx *ctx; + + ctx = tr2tls_get_self(); + + pthread_setspecific(tr2tls_key, NULL); + + free((char *)ctx->thread_name); + free(ctx->array_us_start); + free(ctx); +} + +void tr2tls_push_self(uint64_t us_now) +{ + struct tr2tls_thread_ctx *ctx = tr2tls_get_self(); + + ALLOC_GROW(ctx->array_us_start, ctx->nr_open_regions + 1, ctx->alloc); + ctx->array_us_start[ctx->nr_open_regions++] = us_now; +} + +void tr2tls_pop_self(void) +{ + struct tr2tls_thread_ctx *ctx = tr2tls_get_self(); + + if (!ctx->nr_open_regions) + BUG("no open regions in thread '%s'", ctx->thread_name); + + ctx->nr_open_regions--; +} + +void tr2tls_pop_unwind_self(void) +{ + struct tr2tls_thread_ctx *ctx = tr2tls_get_self(); + + while (ctx->nr_open_regions > 1) + tr2tls_pop_self(); +} + +uint64_t tr2tls_region_elasped_self(uint64_t us) +{ + struct tr2tls_thread_ctx *ctx; + uint64_t us_start; + + ctx = tr2tls_get_self(); + if (!ctx->nr_open_regions) + return 0; + + us_start = ctx->array_us_start[ctx->nr_open_regions - 1]; + + return us - us_start; +} + +uint64_t tr2tls_absolute_elapsed(uint64_t us) +{ + if (!tr2tls_thread_main) + return 0; + + return us - tr2tls_us_start_process; +} + +void tr2tls_init(void) +{ + tr2tls_start_process_clock(); + + pthread_key_create(&tr2tls_key, NULL); + init_recursive_mutex(&tr2tls_mutex); + + tr2tls_thread_main = + tr2tls_create_self("main", tr2tls_us_start_process); +} + +void tr2tls_release(void) +{ + tr2tls_unset_self(); + tr2tls_thread_main = NULL; + + pthread_mutex_destroy(&tr2tls_mutex); + pthread_key_delete(tr2tls_key); +} + +int tr2tls_locked_increment(int *p) +{ + int current_value; + + pthread_mutex_lock(&tr2tls_mutex); + current_value = *p; + *p = current_value + 1; + pthread_mutex_unlock(&tr2tls_mutex); + + return current_value; +} + +void tr2tls_lock(void) +{ + pthread_mutex_lock(&tr2tls_mutex); +} + +void tr2tls_unlock(void) +{ + pthread_mutex_unlock(&tr2tls_mutex); +} -- cgit v1.2.3