From 7d2bac5a384a2fded203298c36ce91b24cbbd497 Mon Sep 17 00:00:00 2001
From: Yinan Zhang <zyn8950@gmail.com>
Date: Tue, 10 Dec 2019 10:46:31 -0800
Subject: [PATCH] Refactor destroy code path for prof_tctx

---
 include/jemalloc/internal/prof_externs.h |  4 ++--
 src/prof.c                               | 28 ++---------------------
 src/prof_data.c                          | 29 +++++++++++++++++++++++-
 3 files changed, 32 insertions(+), 29 deletions(-)

diff --git a/include/jemalloc/internal/prof_externs.h b/include/jemalloc/internal/prof_externs.h
index 6d296920..bd73a296 100644
--- a/include/jemalloc/internal/prof_externs.h
+++ b/include/jemalloc/internal/prof_externs.h
@@ -114,13 +114,13 @@ bool prof_log_rep_check(void);
 void prof_log_dummy_set(bool new_value);
 #endif
 
-/* Functions in prof_data.c only accessed in prof.c */
+/* Functions in prof_data.c only used in profiling code. */
 bool prof_data_init(tsd_t *tsd);
 bool prof_dump(tsd_t *tsd, bool propagate_err, const char *filename,
     bool leakcheck);
 prof_tdata_t * prof_tdata_init_impl(tsd_t *tsd, uint64_t thr_uid,
     uint64_t thr_discrim, char *thread_name, bool active, bool reset_interval);
 void prof_tdata_detach(tsd_t *tsd, prof_tdata_t *tdata);
-void prof_tctx_destroy(tsd_t *tsd, prof_tctx_t *tctx);
+void prof_tctx_try_destroy(tsd_t *tsd, prof_tctx_t *tctx);
 
 #endif /* JEMALLOC_INTERNAL_PROF_EXTERNS_H */
diff --git a/src/prof.c b/src/prof.c
index a9849b05..0d6da21c 100644
--- a/src/prof.c
+++ b/src/prof.c
@@ -128,22 +128,6 @@ prof_strncpy(char *UNUSED dest, const char *UNUSED src, size_t UNUSED size) {
 #endif
 }
 
-static bool
-prof_tctx_should_destroy(tsdn_t *tsdn, prof_tctx_t *tctx) {
-	malloc_mutex_assert_owner(tsdn, tctx->tdata->lock);
-
-	if (opt_prof_accum) {
-		return false;
-	}
-	if (tctx->cnts.curobjs != 0) {
-		return false;
-	}
-	if (tctx->prepared) {
-		return false;
-	}
-	return true;
-}
-
 void
 prof_alloc_rollback(tsd_t *tsd, prof_tctx_t *tctx, bool updated) {
 	cassert(config_prof);
@@ -171,11 +155,7 @@ prof_alloc_rollback(tsd_t *tsd, prof_tctx_t *tctx, bool updated) {
 	if ((uintptr_t)tctx > (uintptr_t)1U) {
 		malloc_mutex_lock(tsd_tsdn(tsd), tctx->tdata->lock);
 		tctx->prepared = false;
-		if (prof_tctx_should_destroy(tsd_tsdn(tsd), tctx)) {
-			prof_tctx_destroy(tsd, tctx);
-		} else {
-			malloc_mutex_unlock(tsd_tsdn(tsd), tctx->tdata->lock);
-		}
+		prof_tctx_try_destroy(tsd, tctx);
 	}
 }
 
@@ -216,11 +196,7 @@ prof_free_sampled_object(tsd_t *tsd, size_t usize, prof_info_t *prof_info) {
 
 	prof_try_log(tsd, usize, prof_info);
 
-	if (prof_tctx_should_destroy(tsd_tsdn(tsd), tctx)) {
-		prof_tctx_destroy(tsd, tctx);
-	} else {
-		malloc_mutex_unlock(tsd_tsdn(tsd), tctx->tdata->lock);
-	}
+	prof_tctx_try_destroy(tsd, tctx);
 }
 
 void
diff --git a/src/prof_data.c b/src/prof_data.c
index ecabed3e..8a2cc845 100644
--- a/src/prof_data.c
+++ b/src/prof_data.c
@@ -1373,7 +1373,23 @@ prof_reset(tsd_t *tsd, size_t lg_sample) {
 	malloc_mutex_unlock(tsd_tsdn(tsd), &prof_dump_mtx);
 }
 
-void
+static bool
+prof_tctx_should_destroy(tsd_t *tsd, prof_tctx_t *tctx) {
+	malloc_mutex_assert_owner(tsd_tsdn(tsd), tctx->tdata->lock);
+
+	if (opt_prof_accum) {
+		return false;
+	}
+	if (tctx->cnts.curobjs != 0) {
+		return false;
+	}
+	if (tctx->prepared) {
+		return false;
+	}
+	return true;
+}
+
+static void
 prof_tctx_destroy(tsd_t *tsd, prof_tctx_t *tctx) {
 	prof_tdata_t *tdata = tctx->tdata;
 	prof_gctx_t *gctx = tctx->gctx;
@@ -1449,4 +1465,15 @@ prof_tctx_destroy(tsd_t *tsd, prof_tctx_t *tctx) {
 	}
 }
 
+void
+prof_tctx_try_destroy(tsd_t *tsd, prof_tctx_t *tctx) {
+	malloc_mutex_assert_owner(tsd_tsdn(tsd), tctx->tdata->lock);
+	if (prof_tctx_should_destroy(tsd, tctx)) {
+		/* tctx->tdata->lock will be released in prof_tctx_destroy(). */
+		prof_tctx_destroy(tsd, tctx);
+	} else {
+		malloc_mutex_unlock(tsd_tsdn(tsd), tctx->tdata->lock);
+	}
+}
+
 /******************************************************************************/