File 0299-Make-persistent_term-put-2-and-persistent_term-erase.patch of Package erlang
From 62da0f2dff72fc5d58e549593fe9c73610713d9c Mon Sep 17 00:00:00 2001
From: Kjell Winblad <kjellwinblad@gmail.com>
Date: Mon, 8 Apr 2019 17:11:25 +0200
Subject: [PATCH] Make persistent_term:put/2 and persistent_term:erase/1 yield
Prior to this commit, the functions put/2 and erase/1 in the
persistent_term module did not yield even if the persistent term table
was large (the persistent term table is copied every time put/2 or
erase/1 is called). Furthermore, a call to put/2 or erase/1 did only
consume a single reduction. This commit fixes these problems.
---
erts/doc/src/persistent_term.xml | 13 -
erts/emulator/beam/erl_alloc.types | 1 +
erts/emulator/beam/erl_bif_persistent.c | 530 +++++++++++++++++++--------
erts/emulator/test/persistent_term_SUITE.erl | 73 +++-
4 files changed, 455 insertions(+), 162 deletions(-)
diff --git a/erts/doc/src/persistent_term.xml b/erts/doc/src/persistent_term.xml
index 9d3c9afd80..672b00a83a 100644
--- a/erts/doc/src/persistent_term.xml
+++ b/erts/doc/src/persistent_term.xml
@@ -120,19 +120,6 @@
erl +MIscs 2048</pre>
</section>
- <section>
- <title>Warning For Many Persistent Terms</title>
- <p>The runtime system will send a warning report to the
- error logger if more than 20000 persistent terms have been
- created. It will look like this:</p>
-
-<pre>
-More than 20000 persistent terms have been created.
-It is recommended to avoid creating an excessive number of
-persistent terms, as creation and deletion of persistent terms
-will be slower as the number of persistent terms increases.</pre>
- </section>
-
<section>
<title>Best Practices for Using Persistent Terms</title>
diff --git a/erts/emulator/beam/erl_alloc.types b/erts/emulator/beam/erl_alloc.types
index e7329daa2d..92e5069c71 100644
--- a/erts/emulator/beam/erl_alloc.types
+++ b/erts/emulator/beam/erl_alloc.types
@@ -282,6 +282,7 @@ type ENVIRONMENT SYSTEM SYSTEM environment
type PERSISTENT_TERM LONG_LIVED CODE persisten_term
type PERSISTENT_LOCK_Q SHORT_LIVED SYSTEM persistent_lock_q
+type PERSISTENT_TERM_TMP SHORT_LIVED SYSTEM persistent_term_tmp_table
#
# Types used for special emulators
diff --git a/erts/emulator/beam/erl_bif_persistent.c b/erts/emulator/beam/erl_bif_persistent.c
index 5a78a043ce..f38e0cc5cb 100644
--- a/erts/emulator/beam/erl_bif_persistent.c
+++ b/erts/emulator/beam/erl_bif_persistent.c
@@ -36,15 +36,6 @@
#include "erl_map.h"
#include "erl_binary.h"
-/*
- * The limit for the number of persistent terms before
- * a warning is issued.
- */
-
-#define WARNING_LIMIT 20000
-#define XSTR(s) STR(s)
-#define STR(s) #s
-
/*
* Parameters for the hash table.
*/
@@ -73,14 +64,69 @@ typedef struct trap_data {
Uint memory; /* Used by info/0 to count used memory */
} TrapData;
+typedef enum {
+ ERTS_PERSISTENT_TERM_CPY_PLACE_START,
+ ERTS_PERSISTENT_TERM_CPY_PLACE_1,
+ ERTS_PERSISTENT_TERM_CPY_PLACE_2,
+ ERTS_PERSISTENT_TERM_CPY_PLACE_3
+} ErtsPersistentTermCpyTableLocation;
+
+typedef enum {
+ ERTS_PERSISTENT_TERM_CPY_NO_REHASH = 0,
+ ERTS_PERSISTENT_TERM_CPY_REHASH = 1,
+ ERTS_PERSISTENT_TERM_CPY_TEMP = 2
+} ErtsPersistentTermCpyTableType;
+
+typedef struct {
+ HashTable* old_table; /* in param */
+ Uint new_size; /* in param */
+ ErtsPersistentTermCpyTableType copy_type; /* in param */
+ Uint max_iterations; /* in param */
+ ErtsPersistentTermCpyTableLocation location; /* in/out param */
+ Uint iterations_done; /* in/out param */
+ Uint total_iterations_done; /* in/out param */
+ HashTable* new_table; /* out param */
+} ErtsPersistentTermCpyTableCtx;
+
+typedef enum {
+ PUT2_TRAP_LOCATION_NEW_KEY,
+ PUT2_TRAP_LOCATION_REPLACE_VALUE
+} ErtsPersistentTermPut2TrapLocation;
+
+typedef struct {
+ ErtsPersistentTermPut2TrapLocation trap_location;
+ Eterm key;
+ Eterm term;
+ Uint entry_index;
+ HashTable* hash_table;
+ Eterm heap[3];
+ Eterm tuple;
+ ErtsPersistentTermCpyTableCtx cpy_ctx;
+} ErtsPersistentTermPut2Context;
+
+typedef enum {
+ ERASE1_TRAP_LOCATION_TMP_COPY,
+ ERASE1_TRAP_LOCATION_FINAL_COPY
+} ErtsPersistentTermErase1TrapLocation;
+
+typedef struct {
+ ErtsPersistentTermErase1TrapLocation trap_location;
+ Eterm key;
+ HashTable* old_table;
+ HashTable* new_table;
+ Uint entry_index;
+ Eterm old_term;
+ HashTable* tmp_table;
+ ErtsPersistentTermCpyTableCtx cpy_ctx;
+} ErtsPersistentTermErase1Context;
+
/*
* Declarations of local functions.
*/
static HashTable* create_initial_table(void);
static Uint lookup(HashTable* hash_table, Eterm key);
-static HashTable* copy_table(HashTable* old_table, Uint new_size, int rehash);
-static HashTable* tmp_table_copy(HashTable* old_table);
+static HashTable* copy_table(ErtsPersistentTermCpyTableCtx* ctx);
static int try_seize_update_permission(Process* c_p);
static void release_update_permission(int release_updater);
static void table_updater(void* table);
@@ -127,7 +173,6 @@ static Process* updater_process = NULL;
/* Protected by update_table_permission_mtx */
static ErtsThrPrgrLaterOp thr_prog_op;
-static int issued_warning = 0;
/*
* Queue of hash tables to be deleted.
@@ -139,7 +184,7 @@ static HashTable** delete_queue_tail = &delete_queue_head;
/*
* The following variables are only used during crash dumping. They
- * are intialized by erts_init_persistent_dumping().
+ * are initialized by erts_init_persistent_dumping().
*/
ErtsLiteralArea** erts_persistent_areas;
@@ -188,101 +233,181 @@ void erts_init_bif_persistent_term(void)
&persistent_term_info_trap);
}
+/*
+ * Macro used for trapping in persistent_term_put_2 and
+ * persistent_term_erase_1
+ */
+#define TRAPPING_COPY_TABLE(TABLE_DEST, OLD_TABLE, NEW_SIZE, COPY_TYPE, LOC_NAME, TRAP_CODE) \
+ do { \
+ ctx->cpy_ctx = (ErtsPersistentTermCpyTableCtx){ \
+ .old_table = OLD_TABLE, \
+ .new_size = NEW_SIZE, \
+ .copy_type = COPY_TYPE, \
+ .location = ERTS_PERSISTENT_TERM_CPY_PLACE_START \
+ }; \
+ L_ ## LOC_NAME: \
+ ctx->cpy_ctx.max_iterations = MAX(1, max_iterations); \
+ TABLE_DEST = copy_table(&ctx->cpy_ctx); \
+ iterations_until_trap -= ctx->cpy_ctx.total_iterations_done; \
+ if (TABLE_DEST == NULL) { \
+ ctx->trap_location = LOC_NAME; \
+ erts_set_gc_state(BIF_P, 0); \
+ BUMP_ALL_REDS(BIF_P); \
+ TRAP_CODE; \
+ } \
+ } while (0)
+
+static int persistent_term_put_2_ctx_bin_dtor(Binary *context_bin)
+{
+ ErtsPersistentTermPut2Context* ctx = ERTS_MAGIC_BIN_DATA(context_bin);
+ if (ctx->cpy_ctx.new_table != NULL) {
+ erts_free(ERTS_ALC_T_PERSISTENT_TERM, ctx->cpy_ctx.new_table);
+ release_update_permission(0);
+ }
+ return 1;
+}
+/*
+ * A linear congruential generator that is used in the debug emulator
+ * to trap after a random number of iterations in
+ * persistent_term_put_2 and persistent_term_erase_1.
+ *
+ * https://en.wikipedia.org/wiki/Linear_congruential_generator
+ */
+#define GET_SMALL_RANDOM_INT(SEED) \
+ (1103515245 * (SEED) + 12345) % 227
+
BIF_RETTYPE persistent_term_put_2(BIF_ALIST_2)
{
- Eterm key;
- Eterm term;
- Eterm heap[3];
- Eterm tuple;
- HashTable* hash_table;
- Uint term_size;
- Uint lit_area_size;
- ErlOffHeap code_off_heap;
- ErtsLiteralArea* literal_area;
- erts_shcopy_t info;
- Eterm* ptr;
- Uint entry_index;
+ static const Uint ITERATIONS_PER_RED = 32;
+ ErtsPersistentTermPut2Context* ctx;
+ Eterm state_mref = THE_NON_VALUE;
+ long iterations_until_trap;
+ long max_iterations;
+#define PUT_TRAP_CODE \
+ BIF_TRAP2(bif_export[BIF_persistent_term_put_2], BIF_P, state_mref, BIF_ARG_2)
+#define TRAPPING_COPY_TABLE_PUT(TABLE_DEST, OLD_TABLE, NEW_SIZE, COPY_TYPE, LOC_NAME) \
+ TRAPPING_COPY_TABLE(TABLE_DEST, OLD_TABLE, NEW_SIZE, COPY_TYPE, LOC_NAME, PUT_TRAP_CODE)
+
+#ifdef DEBUG
+ (void)ITERATIONS_PER_RED;
+ iterations_until_trap = max_iterations =
+ GET_SMALL_RANDOM_INT(ERTS_BIF_REDS_LEFT(BIF_P) + (Uint)&ctx);
+#else
+ iterations_until_trap = max_iterations =
+ ITERATIONS_PER_RED * ERTS_BIF_REDS_LEFT(BIF_P);
+#endif
+ if (is_internal_magic_ref(BIF_ARG_1) &&
+ (ERTS_MAGIC_BIN_DESTRUCTOR(erts_magic_ref2bin(BIF_ARG_1)) ==
+ persistent_term_put_2_ctx_bin_dtor)) {
+ /* Restore state after a trap */
+ Binary* state_bin;
+ state_mref = BIF_ARG_1;
+ state_bin = erts_magic_ref2bin(state_mref);
+ ctx = ERTS_MAGIC_BIN_DATA(state_bin);
+ ASSERT(BIF_P->flags & F_DISABLE_GC);
+ erts_set_gc_state(BIF_P, 1);
+ switch (ctx->trap_location) {
+ case PUT2_TRAP_LOCATION_NEW_KEY:
+ goto L_PUT2_TRAP_LOCATION_NEW_KEY;
+ case PUT2_TRAP_LOCATION_REPLACE_VALUE:
+ goto L_PUT2_TRAP_LOCATION_REPLACE_VALUE;
+ }
+ } else {
+ /* Save state in magic bin in case trapping is necessary */
+ Eterm* hp;
+ Binary* state_bin = erts_create_magic_binary(sizeof(ErtsPersistentTermPut2Context),
+ persistent_term_put_2_ctx_bin_dtor);
+ hp = HAlloc(BIF_P, ERTS_MAGIC_REF_THING_SIZE);
+ state_mref = erts_mk_magic_ref(&hp, &MSO(BIF_P), state_bin);
+ ctx = ERTS_MAGIC_BIN_DATA(state_bin);
+ /*
+ * IMPORTANT: The following field is used to detect if
+ * persistent_term_put_2_ctx_bin_dtor needs to free memory
+ */
+ ctx->cpy_ctx.new_table = NULL;
+ }
+
if (!try_seize_update_permission(BIF_P)) {
ERTS_BIF_YIELD2(bif_export[BIF_persistent_term_put_2],
BIF_P, BIF_ARG_1, BIF_ARG_2);
}
+ ctx->hash_table = (HashTable *) erts_atomic_read_nob(&the_hash_table);
- hash_table = (HashTable *) erts_atomic_read_nob(&the_hash_table);
+ ctx->key = BIF_ARG_1;
+ ctx->term = BIF_ARG_2;
- key = BIF_ARG_1;
- term = BIF_ARG_2;
+ ctx->entry_index = lookup(ctx->hash_table, ctx->key);
- entry_index = lookup(hash_table, key);
-
- heap[0] = make_arityval(2);
- heap[1] = key;
- heap[2] = term;
- tuple = make_tuple(heap);
+ ctx->heap[0] = make_arityval(2);
+ ctx->heap[1] = ctx->key;
+ ctx->heap[2] = ctx->term;
+ ctx->tuple = make_tuple(ctx->heap);
- if (is_nil(hash_table->term[entry_index])) {
- Uint size = hash_table->allocated;
- if (MUST_GROW(hash_table)) {
- size *= 2;
+ if (is_nil(ctx->hash_table->term[ctx->entry_index])) {
+ Uint new_size = ctx->hash_table->allocated;
+ if (MUST_GROW(ctx->hash_table)) {
+ new_size *= 2;
}
- hash_table = copy_table(hash_table, size, 0);
- entry_index = lookup(hash_table, key);
- hash_table->num_entries++;
+ TRAPPING_COPY_TABLE_PUT(ctx->hash_table,
+ ctx->hash_table,
+ new_size,
+ ERTS_PERSISTENT_TERM_CPY_NO_REHASH,
+ PUT2_TRAP_LOCATION_NEW_KEY);
+ ctx->entry_index = lookup(ctx->hash_table, ctx->key);
+ ctx->hash_table->num_entries++;
} else {
- Eterm tuple = hash_table->term[entry_index];
+ Eterm tuple = ctx->hash_table->term[ctx->entry_index];
Eterm old_term;
ASSERT(is_tuple_arity(tuple, 2));
old_term = boxed_val(tuple)[2];
- if (EQ(term, old_term)) {
+ if (EQ(ctx->term, old_term)) {
/* Same value. No need to update anything. */
release_update_permission(0);
BIF_RET(am_ok);
} else {
/* Mark the old term for deletion. */
- mark_for_deletion(hash_table, entry_index);
- hash_table = copy_table(hash_table, hash_table->allocated, 0);
+ mark_for_deletion(ctx->hash_table, ctx->entry_index);
+ TRAPPING_COPY_TABLE_PUT(ctx->hash_table,
+ ctx->hash_table,
+ ctx->hash_table->allocated,
+ ERTS_PERSISTENT_TERM_CPY_NO_REHASH,
+ PUT2_TRAP_LOCATION_REPLACE_VALUE);
}
}
- /*
- * Preserve internal sharing in the term by using the
- * sharing-preserving functions. However, literals must
- * be copied in case the module holding them are unloaded.
- */
- INITIALIZE_SHCOPY(info);
- info.copy_literals = 1;
- term_size = copy_shared_calculate(tuple, &info);
- ERTS_INIT_OFF_HEAP(&code_off_heap);
- lit_area_size = ERTS_LITERAL_AREA_ALLOC_SIZE(term_size);
- literal_area = erts_alloc(ERTS_ALC_T_LITERAL, lit_area_size);
- ptr = &literal_area->start[0];
- literal_area->end = ptr + term_size;
- tuple = copy_shared_perform(tuple, term_size, &info, &ptr, &code_off_heap);
- ASSERT(tuple_val(tuple) == literal_area->start);
- literal_area->off_heap = code_off_heap.first;
- DESTROY_SHCOPY(info);
- erts_set_literal_tag(&tuple, literal_area->start, term_size);
- hash_table->term[entry_index] = tuple;
-
- erts_schedule_thr_prgr_later_op(table_updater, hash_table, &thr_prog_op);
- suspend_updater(BIF_P);
-
- /*
- * Issue a warning once if the warning limit has been exceeded.
- */
-
- if (hash_table->num_entries > WARNING_LIMIT && issued_warning == 0) {
- static char w[] =
- "More than " XSTR(WARNING_LIMIT) " persistent terms "
- "have been created.\n"
- "It is recommended to avoid creating an excessive number of\n"
- "persistent terms, as creation and deletion of persistent terms\n"
- "will be slower as the number of persistent terms increases.\n";
- issued_warning = 1;
- erts_send_warning_to_logger_str(BIF_P->group_leader, w);
+ {
+ Uint term_size;
+ Uint lit_area_size;
+ ErlOffHeap code_off_heap;
+ ErtsLiteralArea* literal_area;
+ erts_shcopy_t info;
+ Eterm* ptr;
+ /*
+ * Preserve internal sharing in the term by using the
+ * sharing-preserving functions. However, literals must
+ * be copied in case the module holding them are unloaded.
+ */
+ INITIALIZE_SHCOPY(info);
+ info.copy_literals = 1;
+ term_size = copy_shared_calculate(ctx->tuple, &info);
+ ERTS_INIT_OFF_HEAP(&code_off_heap);
+ lit_area_size = ERTS_LITERAL_AREA_ALLOC_SIZE(term_size);
+ literal_area = erts_alloc(ERTS_ALC_T_LITERAL, lit_area_size);
+ ptr = &literal_area->start[0];
+ literal_area->end = ptr + term_size;
+ ctx->tuple = copy_shared_perform(ctx->tuple, term_size, &info, &ptr, &code_off_heap);
+ ASSERT(tuple_val(ctx->tuple) == literal_area->start);
+ literal_area->off_heap = code_off_heap.first;
+ DESTROY_SHCOPY(info);
+ erts_set_literal_tag(&ctx->tuple, literal_area->start, term_size);
+ ctx->hash_table->term[ctx->entry_index] = ctx->tuple;
+
+ erts_schedule_thr_prgr_later_op(table_updater, ctx->hash_table, &thr_prog_op);
+ suspend_updater(BIF_P);
}
-
+ BUMP_REDS(BIF_P, (max_iterations - iterations_until_trap) / ITERATIONS_PER_RED);
ERTS_BIF_YIELD_RETURN(BIF_P, am_ok);
}
@@ -349,26 +474,84 @@ BIF_RETTYPE persistent_term_get_2(BIF_ALIST_2)
BIF_RET(result);
}
-BIF_RETTYPE persistent_term_erase_1(BIF_ALIST_1)
+static int persistent_term_erase_1_ctx_bin_dtor(Binary *context_bin)
{
- Eterm key = BIF_ARG_1;
- HashTable* old_table;
- HashTable* new_table;
- Uint entry_index;
- Eterm old_term;
+ ErtsPersistentTermErase1Context* ctx = ERTS_MAGIC_BIN_DATA(context_bin);
+ if (ctx->cpy_ctx.new_table != NULL) {
+ if (ctx->cpy_ctx.copy_type == ERTS_PERSISTENT_TERM_CPY_TEMP) {
+ erts_free(ERTS_ALC_T_PERSISTENT_TERM_TMP, ctx->cpy_ctx.new_table);
+ } else {
+ erts_free(ERTS_ALC_T_PERSISTENT_TERM, ctx->cpy_ctx.new_table);
+ }
+ if (ctx->tmp_table != NULL) {
+ erts_free(ERTS_ALC_T_PERSISTENT_TERM_TMP, ctx->tmp_table);
+ }
+ release_update_permission(0);
+ }
+ return 1;
+}
+BIF_RETTYPE persistent_term_erase_1(BIF_ALIST_1)
+{
+ static const Uint ITERATIONS_PER_RED = 32;
+ ErtsPersistentTermErase1Context* ctx;
+ Eterm state_mref = THE_NON_VALUE;
+ long iterations_until_trap;
+ long max_iterations;
+#ifdef DEBUG
+ (void)ITERATIONS_PER_RED;
+ iterations_until_trap = max_iterations =
+ GET_SMALL_RANDOM_INT(ERTS_BIF_REDS_LEFT(BIF_P) + (Uint)&ctx);
+#else
+ iterations_until_trap = max_iterations =
+ ITERATIONS_PER_RED * ERTS_BIF_REDS_LEFT(BIF_P);
+#endif
+#define ERASE_TRAP_CODE \
+ BIF_TRAP1(bif_export[BIF_persistent_term_erase_1], BIF_P, state_mref);
+#define TRAPPING_COPY_TABLE_ERASE(TABLE_DEST, OLD_TABLE, NEW_SIZE, REHASH, LOC_NAME) \
+ TRAPPING_COPY_TABLE(TABLE_DEST, OLD_TABLE, NEW_SIZE, REHASH, LOC_NAME, ERASE_TRAP_CODE)
+ if (is_internal_magic_ref(BIF_ARG_1) &&
+ (ERTS_MAGIC_BIN_DESTRUCTOR(erts_magic_ref2bin(BIF_ARG_1)) ==
+ persistent_term_erase_1_ctx_bin_dtor)) {
+ /* Restore the state after a trap */
+ Binary* state_bin;
+ state_mref = BIF_ARG_1;
+ state_bin = erts_magic_ref2bin(state_mref);
+ ctx = ERTS_MAGIC_BIN_DATA(state_bin);
+ ASSERT(BIF_P->flags & F_DISABLE_GC);
+ erts_set_gc_state(BIF_P, 1);
+ switch (ctx->trap_location) {
+ case ERASE1_TRAP_LOCATION_TMP_COPY:
+ goto L_ERASE1_TRAP_LOCATION_TMP_COPY;
+ case ERASE1_TRAP_LOCATION_FINAL_COPY:
+ goto L_ERASE1_TRAP_LOCATION_FINAL_COPY;
+ }
+ } else {
+ /* Save state in magic bin in case trapping is necessary */
+ Eterm* hp;
+ Binary* state_bin = erts_create_magic_binary(sizeof(ErtsPersistentTermErase1Context),
+ persistent_term_erase_1_ctx_bin_dtor);
+ hp = HAlloc(BIF_P, ERTS_MAGIC_REF_THING_SIZE);
+ state_mref = erts_mk_magic_ref(&hp, &MSO(BIF_P), state_bin);
+ ctx = ERTS_MAGIC_BIN_DATA(state_bin);
+ /*
+ * IMPORTANT: The following two fields are used to detect if
+ * persistent_term_erase_1_ctx_bin_dtor needs to free memory
+ */
+ ctx->cpy_ctx.new_table = NULL;
+ ctx->tmp_table = NULL;
+ }
if (!try_seize_update_permission(BIF_P)) {
ERTS_BIF_YIELD1(bif_export[BIF_persistent_term_erase_1],
BIF_P, BIF_ARG_1);
}
- old_table = (HashTable *) erts_atomic_read_nob(&the_hash_table);
- entry_index = lookup(old_table, key);
- old_term = old_table->term[entry_index];
- if (is_boxed(old_term)) {
+ ctx->key = BIF_ARG_1;
+ ctx->old_table = (HashTable *) erts_atomic_read_nob(&the_hash_table);
+ ctx->entry_index = lookup(ctx->old_table, ctx->key);
+ ctx->old_term = ctx->old_table->term[ctx->entry_index];
+ if (is_boxed(ctx->old_term)) {
Uint new_size;
- HashTable* tmp_table;
-
/*
* Since we don't use any delete markers, we must rehash
* the table when deleting terms to ensure that all terms
@@ -378,8 +561,12 @@ BIF_RETTYPE persistent_term_erase_1(BIF_ALIST_1)
* temporary table copy of the same size as the old one.
*/
- ASSERT(is_tuple_arity(old_term, 2));
- tmp_table = tmp_table_copy(old_table);
+ ASSERT(is_tuple_arity(ctx->old_term, 2));
+ TRAPPING_COPY_TABLE_ERASE(ctx->tmp_table,
+ ctx->old_table,
+ ctx->old_table->allocated,
+ ERTS_PERSISTENT_TERM_CPY_TEMP,
+ ERASE1_TRAP_LOCATION_TMP_COPY);
/*
* Delete the term from the temporary table. Then copy the
@@ -387,18 +574,28 @@ BIF_RETTYPE persistent_term_erase_1(BIF_ALIST_1)
* while copying.
*/
- tmp_table->term[entry_index] = NIL;
- tmp_table->num_entries--;
- new_size = tmp_table->allocated;
- if (MUST_SHRINK(tmp_table)) {
+ ctx->tmp_table->term[ctx->entry_index] = NIL;
+ ctx->tmp_table->num_entries--;
+ new_size = ctx->tmp_table->allocated;
+ if (MUST_SHRINK(ctx->tmp_table)) {
new_size /= 2;
}
- new_table = copy_table(tmp_table, new_size, 1);
- erts_free(ERTS_ALC_T_TMP, tmp_table);
+ TRAPPING_COPY_TABLE_ERASE(ctx->new_table,
+ ctx->tmp_table,
+ new_size,
+ ERTS_PERSISTENT_TERM_CPY_REHASH,
+ ERASE1_TRAP_LOCATION_FINAL_COPY);
+ erts_free(ERTS_ALC_T_PERSISTENT_TERM_TMP, ctx->tmp_table);
+ /*
+ * IMPORTANT: Memory management depends on that ctx->tmp_table
+ * is set to NULL on the line below
+ */
+ ctx->tmp_table = NULL;
- mark_for_deletion(old_table, entry_index);
- erts_schedule_thr_prgr_later_op(table_updater, new_table, &thr_prog_op);
+ mark_for_deletion(ctx->old_table, ctx->entry_index);
+ erts_schedule_thr_prgr_later_op(table_updater, ctx->new_table, &thr_prog_op);
suspend_updater(BIF_P);
+ BUMP_REDS(BIF_P, (max_iterations - iterations_until_trap) / ITERATIONS_PER_RED);
ERTS_BIF_YIELD_RETURN(BIF_P, am_true);
}
@@ -406,7 +603,7 @@ BIF_RETTYPE persistent_term_erase_1(BIF_ALIST_1)
* Key is not present. Nothing to do.
*/
- ASSERT(is_nil(old_term));
+ ASSERT(is_nil(ctx->old_term));
release_update_permission(0);
BIF_RET(am_false);
}
@@ -740,65 +937,104 @@ lookup(HashTable* hash_table, Eterm key)
}
static HashTable*
-tmp_table_copy(HashTable* old_table)
+copy_table(ErtsPersistentTermCpyTableCtx* ctx)
{
- Uint size = old_table->allocated;
- HashTable* tmp_table;
+ Uint old_size = ctx->old_table->allocated;
Uint i;
-
- tmp_table = (HashTable *) erts_alloc(ERTS_ALC_T_TMP,
- sizeof(HashTable) +
- sizeof(Eterm) * (size-1));
- *tmp_table = *old_table;
- for (i = 0; i < size; i++) {
- tmp_table->term[i] = old_table->term[i];
+ ErtsAlcType_t alloc_type;
+ ctx->total_iterations_done = 0;
+ switch(ctx->location) {
+ case ERTS_PERSISTENT_TERM_CPY_PLACE_1: goto L_copy_table_place_1;
+ case ERTS_PERSISTENT_TERM_CPY_PLACE_2: goto L_copy_table_place_2;
+ case ERTS_PERSISTENT_TERM_CPY_PLACE_3: goto L_copy_table_place_3;
+ case ERTS_PERSISTENT_TERM_CPY_PLACE_START:
+ ctx->iterations_done = 0;
}
- return tmp_table;
-}
-
-static HashTable*
-copy_table(HashTable* old_table, Uint new_size, int rehash)
-{
- HashTable* new_table;
- Uint old_size = old_table->allocated;
- Uint i;
-
- new_table = (HashTable *) erts_alloc(ERTS_ALC_T_PERSISTENT_TERM,
- sizeof(HashTable) +
- sizeof(Eterm) * (new_size-1));
- if (old_table->allocated == new_size && !rehash) {
+ if (ctx->copy_type == ERTS_PERSISTENT_TERM_CPY_TEMP) {
+ alloc_type = ERTS_ALC_T_PERSISTENT_TERM_TMP;
+ } else {
+ alloc_type = ERTS_ALC_T_PERSISTENT_TERM;
+ }
+ ctx->new_table = (HashTable *) erts_alloc(alloc_type,
+ sizeof(HashTable) +
+ sizeof(Eterm) * (ctx->new_size-1));
+ if (ctx->old_table->allocated == ctx->new_size &&
+ (ctx->copy_type == ERTS_PERSISTENT_TERM_CPY_NO_REHASH ||
+ ctx->copy_type == ERTS_PERSISTENT_TERM_CPY_TEMP)) {
/*
* Same size and no key deleted. Make an exact copy of the table.
*/
- *new_table = *old_table;
- for (i = 0; i < new_size; i++) {
- new_table->term[i] = old_table->term[i];
+ *ctx->new_table = *ctx->old_table;
+ L_copy_table_place_1:
+ for (i = ctx->iterations_done;
+ i < MIN(ctx->iterations_done + ctx->max_iterations,
+ ctx->new_size);
+ i++) {
+ ctx->new_table->term[i] = ctx->old_table->term[i];
}
+ ctx->total_iterations_done = (i - ctx->iterations_done);
+ if (i < ctx->new_size) {
+ ctx->iterations_done = i;
+ ctx->location = ERTS_PERSISTENT_TERM_CPY_PLACE_1;
+ return NULL;
+ }
+ ctx->iterations_done = 0;
} else {
/*
* The size of the table has changed or an element has been
* deleted. Must rehash, by inserting all old terms into the
* new (empty) table.
*/
- new_table->allocated = new_size;
- new_table->num_entries = old_table->num_entries;
- new_table->mask = new_size - 1;
- for (i = 0; i < new_size; i++) {
- new_table->term[i] = NIL;
+ ctx->new_table->allocated = ctx->new_size;
+ ctx->new_table->num_entries = ctx->old_table->num_entries;
+ ctx->new_table->mask = ctx->new_size - 1;
+ L_copy_table_place_2:
+ for (i = ctx->iterations_done;
+ i < MIN(ctx->iterations_done + ctx->max_iterations,
+ ctx->new_size);
+ i++) {
+ ctx->new_table->term[i] = NIL;
+ }
+ ctx->total_iterations_done = (i - ctx->iterations_done);
+ ctx->max_iterations -= ctx->total_iterations_done;
+ if (i < ctx->new_size) {
+ ctx->iterations_done = i;
+ ctx->location = ERTS_PERSISTENT_TERM_CPY_PLACE_2;
+ return NULL;
}
- for (i = 0; i < old_size; i++) {
- if (is_tuple(old_table->term[i])) {
- Eterm key = tuple_val(old_table->term[i])[1];
- Uint entry_index = lookup(new_table, key);
- ASSERT(is_nil(new_table->term[entry_index]));
- new_table->term[entry_index] = old_table->term[i];
+ ctx->iterations_done = 0;
+ L_copy_table_place_3:
+ for (i = ctx->iterations_done;
+ i < MIN(ctx->iterations_done + ctx->max_iterations,
+ old_size);
+ i++) {
+ if (is_tuple(ctx->old_table->term[i])) {
+ Eterm key = tuple_val(ctx->old_table->term[i])[1];
+ Uint entry_index = lookup(ctx->new_table, key);
+ ASSERT(is_nil(ctx->new_table->term[entry_index]));
+ ctx->new_table->term[entry_index] = ctx->old_table->term[i];
}
}
+ ctx->total_iterations_done += (i - ctx->iterations_done);
+ if (i < old_size) {
+ ctx->iterations_done = i;
+ ctx->location = ERTS_PERSISTENT_TERM_CPY_PLACE_3;
+ return NULL;
+ }
+ ctx->iterations_done = 0;
+ }
+ ctx->new_table->first_to_delete = 0;
+ ctx->new_table->num_to_delete = 0;
+ erts_atomic_init_nob(&ctx->new_table->refc, (erts_aint_t)1);
+ {
+ HashTable* new_table = ctx->new_table;
+ /*
+ * IMPORTANT: Memory management depends on that ctx->new_table is
+ * set to NULL on the line below
+ */
+ ctx->new_table = NULL;
+ return new_table;
}
- new_table->first_to_delete = 0;
- new_table->num_to_delete = 0;
- erts_atomic_init_nob(&new_table->refc, (erts_aint_t)1);
- return new_table;
}
static void
diff --git a/erts/emulator/test/persistent_term_SUITE.erl b/erts/emulator/test/persistent_term_SUITE.erl
index 93eb026ced..c9874e5679 100644
--- a/erts/emulator/test/persistent_term_SUITE.erl
+++ b/erts/emulator/test/persistent_term_SUITE.erl
@@ -25,7 +25,10 @@
basic/1,purging/1,sharing/1,get_trapping/1,
info/1,info_trapping/1,killed_while_trapping/1,
off_heap_values/1,keys/1,collisions/1,
- init_restart/1,whole_message/1]).
+ init_restart/1, put_erase_trapping/1,
+ killed_while_trapping_put/1,
+ killed_while_trapping_erase/1,
+ whole_message/1]).
%%
-export([test_init_restart_cmd/1]).
@@ -37,7 +40,9 @@ suite() ->
all() ->
[basic,purging,sharing,get_trapping,info,info_trapping,
killed_while_trapping,off_heap_values,keys,collisions,
- init_restart,whole_message].
+ init_restart, put_erase_trapping, killed_while_trapping_put,
+ killed_while_trapping_erase,
+ whole_message].
init_per_suite(Config) ->
%% Put a term in the dict so that we know that the testcases handle
@@ -669,3 +674,69 @@ chk_not_stuck(Term) ->
pget({_, Initial}) ->
persistent_term:get() -- Initial.
+
+
+killed_while_trapping_put(_Config) ->
+ erts_debug:set_internal_state(available_internal_state, true),
+ repeat(
+ fun() ->
+ NrOfPutsInChild = 10000,
+ do_puts(2500, my_value),
+ Pid =
+ spawn(fun() ->
+ do_puts(NrOfPutsInChild, my_value2)
+ end),
+ timer:sleep(1),
+ erlang:exit(Pid, kill),
+ do_erases(NrOfPutsInChild)
+ end,
+ 10),
+ erts_debug:set_internal_state(available_internal_state, false).
+
+killed_while_trapping_erase(_Config) ->
+ erts_debug:set_internal_state(available_internal_state, true),
+ repeat(
+ fun() ->
+ NrOfErases = 2500,
+ do_puts(NrOfErases, my_value),
+ Pid =
+ spawn(fun() ->
+ do_erases(NrOfErases)
+ end),
+ timer:sleep(1),
+ erlang:exit(Pid, kill),
+ do_erases(NrOfErases)
+ end,
+ 10),
+ erts_debug:set_internal_state(available_internal_state, false).
+
+put_erase_trapping(_Config) ->
+ NrOfItems = 5000,
+ erts_debug:set_internal_state(available_internal_state, true),
+ do_puts(NrOfItems, first),
+ do_puts(NrOfItems, second),
+ do_erases(NrOfItems),
+ erts_debug:set_internal_state(available_internal_state, false).
+
+do_puts(0, _) -> ok;
+do_puts(NrOfPuts, ValuePrefix) ->
+ Key = {?MODULE, NrOfPuts},
+ Value = {ValuePrefix, NrOfPuts},
+ erts_debug:set_internal_state(reds_left, rand:uniform(250)),
+ persistent_term:put(Key, Value),
+ Value = persistent_term:get(Key),
+ do_puts(NrOfPuts - 1, ValuePrefix).
+
+do_erases(0) -> ok;
+do_erases(NrOfErases) ->
+ Key = {?MODULE,NrOfErases},
+ erts_debug:set_internal_state(reds_left, rand:uniform(500)),
+ persistent_term:erase(Key),
+ not_found = persistent_term:get(Key, not_found),
+ do_erases(NrOfErases - 1).
+
+repeat(_Fun, 0) ->
+ ok;
+repeat(Fun, N) ->
+ Fun(),
+ repeat(Fun, N-1).
--
2.16.4
