+2019-05-17 Wilco Dijkstra <wdijkstr@arm.com>
+
+ * malloc/malloc.c (MAX_TCACHE_COUNT): Increase to UINT16_MAX.
+ (tcache_put): Remove redundant assert.
+ (tcache_get): Remove redundant asserts.
+ (__libc_malloc): Check tcache count is not zero.
+ * manual/tunables.texi (glibc.malloc.tcache_count): Update maximum.
+
2019-05-17 Florian Weimer <fweimer@redhat.com>
* manual/llio.texi (Open-time Flags): Document O_DIRECTORY.
/* This is another arbitrary limit, which tunables can change. Each
tcache bin will hold at most this number of chunks. */
# define TCACHE_FILL_COUNT 7
+
+/* Maximum chunks in tcache bins for tunables. This value must fit the range
+ of tcache->counts[] entries, else they may overflow. */
+# define MAX_TCACHE_COUNT UINT16_MAX
#endif
time), this is for performance reasons. */
typedef struct tcache_perthread_struct
{
- char counts[TCACHE_MAX_BINS];
+ uint16_t counts[TCACHE_MAX_BINS];
tcache_entry *entries[TCACHE_MAX_BINS];
} tcache_perthread_struct;
-#define MAX_TCACHE_COUNT 127 /* Maximum value of counts[] entries. */
-
static __thread bool tcache_shutting_down = false;
static __thread tcache_perthread_struct *tcache = NULL;
tcache_put (mchunkptr chunk, size_t tc_idx)
{
tcache_entry *e = (tcache_entry *) chunk2mem (chunk);
- assert (tc_idx < TCACHE_MAX_BINS);
/* Mark this chunk as "in the tcache" so the test in _int_free will
detect a double free. */
tcache_get (size_t tc_idx)
{
tcache_entry *e = tcache->entries[tc_idx];
- assert (tc_idx < TCACHE_MAX_BINS);
- assert (tcache->counts[tc_idx] > 0);
tcache->entries[tc_idx] = e->next;
--(tcache->counts[tc_idx]);
e->key = NULL;
DIAG_PUSH_NEEDS_COMMENT;
if (tc_idx < mp_.tcache_bins
- /*&& tc_idx < TCACHE_MAX_BINS*/ /* to appease gcc */
&& tcache
- && tcache->entries[tc_idx] != NULL)
+ && tcache->counts[tc_idx] > 0)
{
return tcache_get (tc_idx);
}
@deftp Tunable glibc.malloc.tcache_count
The maximum number of chunks of each size to cache. The default is 7.
-The upper limit is 127. If set to zero, the per-thread cache is effectively
+The upper limit is 65535. If set to zero, the per-thread cache is effectively
disabled.
The approximate maximum overhead of the per-thread cache is thus equal