From: Jeff Hostetler <jeffhost@xxxxxxxxxxxxx>
Convert the `tr2tls_thread_ctx.thread_name` field from a `strbuf`
to a "flex array" at the end of the context structure.
The `thread_name` field is a constant string that is constructed when
the context is created. Using a (non-const) `strbuf` structure for it
caused some confusion in the past because it implied that someone
could rename a thread after it was created. That usage was not
intended. Changing it to a "flex array" will hopefully make the
intent more clear.
Also, move the maximum thread_name truncation to tr2_tgt_perf.c
because it is the only target that needs to worry about output column
alignment.
Signed-off-by: Jeff Hostetler <jeffhost@xxxxxxxxxxxxx>
---
trace2/tr2_tgt_event.c | 2 +-
trace2/tr2_tgt_perf.c | 8 ++++++--
trace2/tr2_tls.c | 25 +++++++++++++------------
trace2/tr2_tls.h | 9 +--------
4 files changed, 21 insertions(+), 23 deletions(-)
diff --git a/trace2/tr2_tgt_event.c b/trace2/tr2_tgt_event.c
index 37a3163be12..52f9356c695 100644
--- a/trace2/tr2_tgt_event.c
+++ b/trace2/tr2_tgt_event.c
@@ -90,7 +90,7 @@ static void event_fmt_prepare(const char *event_name, const char *file,
jw_object_string(jw, "event", event_name);
jw_object_string(jw, "sid", tr2_sid_get());
- jw_object_string(jw, "thread", ctx->thread_name.buf);
+ jw_object_string(jw, "thread", ctx->thread_name);
/*
* In brief mode, only emit <time> on these 2 event types.
diff --git a/trace2/tr2_tgt_perf.c b/trace2/tr2_tgt_perf.c
index 8cb792488c8..fdeb3292d3a 100644
--- a/trace2/tr2_tgt_perf.c
+++ b/trace2/tr2_tgt_perf.c
@@ -25,6 +25,7 @@ static int tr2env_perf_be_brief;
#define TR2FMT_PERF_FL_WIDTH (28)
#define TR2FMT_PERF_MAX_EVENT_NAME (12)
+#define TR2FMT_PERF_MAX_THREAD_NAME (24)
#define TR2FMT_PERF_REPO_WIDTH (3)
#define TR2FMT_PERF_CATEGORY_WIDTH (12)
@@ -107,8 +108,11 @@ static void perf_fmt_prepare(const char *event_name,
}
strbuf_addf(buf, "d%d | ", tr2_sid_depth());
- strbuf_addf(buf, "%-*s | %-*s | ", TR2_MAX_THREAD_NAME,
- ctx->thread_name.buf, TR2FMT_PERF_MAX_EVENT_NAME,
+ strbuf_addf(buf, "%-*.*s | %-*s | ",
+ TR2FMT_PERF_MAX_THREAD_NAME,
+ TR2FMT_PERF_MAX_THREAD_NAME,
+ ctx->thread_name,
+ TR2FMT_PERF_MAX_EVENT_NAME,
event_name);
len = buf->len + TR2FMT_PERF_REPO_WIDTH;
diff --git a/trace2/tr2_tls.c b/trace2/tr2_tls.c
index 39b41fd2487..89437e773f6 100644
--- a/trace2/tr2_tls.c
+++ b/trace2/tr2_tls.c
@@ -34,7 +34,18 @@ void tr2tls_start_process_clock(void)
struct tr2tls_thread_ctx *tr2tls_create_self(const char *name_hint,
uint64_t us_thread_start)
{
- struct tr2tls_thread_ctx *ctx = xcalloc(1, sizeof(*ctx));
+ struct tr2tls_thread_ctx *ctx;
+ struct strbuf buf_name = STRBUF_INIT;
+ int thread_id = tr2tls_locked_increment(&tr2_next_thread_id);
+
+ if (thread_id)
+ strbuf_addf(&buf_name, "th%02d:", thread_id);
+ strbuf_addstr(&buf_name, name_hint);
+
+ FLEX_ALLOC_MEM(ctx, thread_name, buf_name.buf, buf_name.len);
+ strbuf_release(&buf_name);
+
+ ctx->thread_id = thread_id;
/*
* Implicitly "tr2tls_push_self()" to capture the thread's start
@@ -45,15 +56,6 @@ struct tr2tls_thread_ctx *tr2tls_create_self(const char *name_hint,
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(&ctx->thread_name, 0);
- if (ctx->thread_id)
- strbuf_addf(&ctx->thread_name, "th%02d:", ctx->thread_id);
- strbuf_addstr(&ctx->thread_name, name_hint);
- if (ctx->thread_name.len > TR2_MAX_THREAD_NAME)
- strbuf_setlen(&ctx->thread_name, TR2_MAX_THREAD_NAME);
-
pthread_setspecific(tr2tls_key, ctx);
return ctx;
@@ -95,7 +97,6 @@ void tr2tls_unset_self(void)
pthread_setspecific(tr2tls_key, NULL);
- strbuf_release(&ctx->thread_name);
free(ctx->array_us_start);
free(ctx);
}
@@ -113,7 +114,7 @@ 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.buf);
+ BUG("no open regions in thread '%s'", ctx->thread_name);
ctx->nr_open_regions--;
}
diff --git a/trace2/tr2_tls.h b/trace2/tr2_tls.h
index f1ee58305d6..be0bc73d08f 100644
--- a/trace2/tr2_tls.h
+++ b/trace2/tr2_tls.h
@@ -9,17 +9,12 @@
* There is NO relation to "transport layer security".
*/
-/*
- * Arbitry limit for thread names for column alignment.
- */
-#define TR2_MAX_THREAD_NAME (24)
-
struct tr2tls_thread_ctx {
- struct strbuf thread_name;
uint64_t *array_us_start;
size_t alloc;
size_t nr_open_regions; /* plays role of "nr" in ALLOC_GROW */
int thread_id;
+ char thread_name[FLEX_ARRAY];
};
/*
@@ -32,8 +27,6 @@ struct tr2tls_thread_ctx {
* upon the name of the thread-proc function). For example:
* { .thread_id=10, .thread_name="th10fsm-listen" }
* This helps to identify and distinguish messages from concurrent threads.
- * The ctx.thread_name field is truncated if necessary to help with column
- * alignment in printf-style messages.
*
* In this and all following functions the term "self" refers to the
* current thread.
--
gitgitgadget
