migrate per-thread magazine caches from single-thread scenario to first

Thu Jul 12 15:46:40 2007  Tim Janik  <timj@imendio.com>

        * glib/gslice.c: migrate per-thread magazine caches from single-thread
        scenario to first thread using GSlice after g_thread_init(); based on
        a patch by Tor Lillqvist, fixes #331853.
        removed warning about g_thread_init() being called after other glib
        functions (in particular g_slice* calls), because GSlice can cope
        with this now and the rest of glib is believed to cope as well.

        * tests/slice-threadinit.c: new test program which tests GSlice working
        across g_thread_init() calls.



svn path=/trunk/; revision=5629
This commit is contained in:
Tim Janik 2007-07-12 15:07:52 +00:00 committed by Tim Janik
parent 64acb31862
commit 964d75ebe3
4 changed files with 218 additions and 16 deletions

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@ -1,3 +1,15 @@
Thu Jul 12 15:46:40 2007 Tim Janik <timj@imendio.com>
* glib/gslice.c: migrate per-thread magazine caches from single-thread
scenario to first thread using GSlice after g_thread_init(); based on
a patch by Tor Lillqvist, fixes #331853.
removed warning about g_thread_init() being called after other glib
functions (in particular g_slice* calls), because GSlice can cope
with this now and the rest of glib is believed to cope as well.
* tests/slice-threadinit.c: new test program which tests GSlice working
across g_thread_init() calls.
2007-07-10 Matthias Clasen <mclasen@redhat.com>
* glib/pltcheck.sh: Add g_once_init_enter to the whitelist of

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@ -372,20 +372,14 @@ void
_g_slice_thread_init_nomessage (void)
{
/* we may not use g_error() or friends here */
if (sys_page_size)
{
const char *pname;
/* mem_error ("g_thread_init() must be called before GSlice is used, memory corrupted..."); */
fputs ("\n***MEMORY-WARNING***: ", stderr);
pname = g_get_prgname();
fprintf (stderr, "%s[%u]: GSlice: ", pname ? pname : "", getpid());
fputs ("g_thread_init() must be called before all other GLib functions; "
"memory corruption due to late invocation of g_thread_init() has been detected; "
"this program is likely to crash, leak or unexpectedly abort soon...\n", stderr);
}
if (!sys_page_size)
g_slice_init_nomessage();
else
{
/* g_slice_init_nomessage() has been called already, probably due
* to a g_slice_alloc1() before g_thread_init().
*/
}
private_thread_memory = g_private_new (private_thread_memory_cleanup);
allocator->magazine_mutex = g_mutex_new();
allocator->slab_mutex = g_mutex_new();
@ -429,11 +423,38 @@ thread_memory_from_self (void)
ThreadMemory *tmem = g_private_get (private_thread_memory);
if (G_UNLIKELY (!tmem))
{
const guint n_magazines = MAX_SLAB_INDEX (allocator);
tmem = g_malloc0 (sizeof (ThreadMemory) + sizeof (Magazine) * 2 * n_magazines);
tmem->magazine1 = (Magazine*) (tmem + 1);
tmem->magazine2 = &tmem->magazine1[n_magazines];
static ThreadMemory *single_thread_memory = NULL; /* remember single-thread info for multi-threaded case */
if (single_thread_memory && g_thread_supported ())
{
g_mutex_lock (allocator->slab_mutex);
if (single_thread_memory)
{
/* GSlice has been used before g_thread_init(), and now
* we are running threaded. to cope with it, use the saved
* thread memory structure from when we weren't threaded.
*/
tmem = single_thread_memory;
single_thread_memory = NULL; /* slab_mutex protected when multi-threaded */
}
g_mutex_unlock (allocator->slab_mutex);
}
if (!tmem)
{
const guint n_magazines = MAX_SLAB_INDEX (allocator);
tmem = g_malloc0 (sizeof (ThreadMemory) + sizeof (Magazine) * 2 * n_magazines);
tmem->magazine1 = (Magazine*) (tmem + 1);
tmem->magazine2 = &tmem->magazine1[n_magazines];
}
/* g_private_get/g_private_set works in the single-threaded xor the multi-
* threaded case. but not *across* g_thread_init(), after multi-thread
* initialization it returns NULL for previously set single-thread data.
*/
g_private_set (private_thread_memory, tmem);
/* save single-thread thread memory structure, in case we need to
* pick it up again after multi-thread initialization happened.
*/
if (!single_thread_memory && !g_thread_supported ())
single_thread_memory = tmem; /* no slab_mutex created yet */
}
return tmem;
}

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@ -104,6 +104,7 @@ test_programs = \
slist-test \
slice-test \
slice-color \
slice-threadinit \
spawn-test \
$(spawn_test_win32_gui) \
strfunc-test \
@ -175,6 +176,8 @@ slice_test_SOURCES = slice-test.c memchunks.c
slice_test_LDADD = $(thread_ldadd)
slice_color_SOURCES = slice-color.c memchunks.c
slice_color_LDADD = $(thread_ldadd)
slice_threadinit_SOURCES = slice-threadinit.c
slice_threadinit_LDADD = $(thread_ldadd)
spawn_test_LDADD = $(progs_ldadd)
strfunc_test_LDADD = $(progs_ldadd)
string_test_LDADD = $(progs_ldadd)

166
tests/slice-threadinit.c Normal file
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@ -0,0 +1,166 @@
/* slice-threadinit.c - test GSlice across g_thread_init
* Copyright (C) 2007 Tim Janik
*
* This work is provided "as is"; redistribution and modification
* in whole or in part, in any medium, physical or electronic is
* permitted without restriction.
*
* This work is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
* In no event shall the authors or contributors be liable for any
* direct, indirect, incidental, special, exemplary, or consequential
* damages (including, but not limited to, procurement of substitute
* goods or services; loss of use, data, or profits; or business
* interruption) however caused and on any theory of liability, whether
* in contract, strict liability, or tort (including negligence or
* otherwise) arising in any way out of the use of this software, even
* if advised of the possibility of such damage.
*/
#include <glib.h>
#define N_PAGES (101) /* number of pages to sample */
#define SAMPLE_SIZE (7)
#define PAGE_SIZE (128) /* must be <= minimum GSlice alignment block */
#define MAGAZINE_PROBES { 77, 265, 347 } /* block sizes hopefully unused by g_thread_init */
#define MAX_PROBE_TRIALS (1031) /* must be >= maximum magazine size */
#define ALIGN(size, base) ((base) * (gsize) (((size) + (base) - 1) / (base)))
static struct {
void *page;
void *sample;
} pages[N_PAGES] = { { NULL, }, };
static const guint magazine_probes[] = MAGAZINE_PROBES;
#define N_MAGAZINE_PROBES G_N_ELEMENTS (magazine_probes)
static void
release_trash_list (GSList **trash_list,
gsize block_size)
{
while (*trash_list)
{
g_slice_free1 (block_size, (*trash_list)->data);
*trash_list = g_slist_delete_link (*trash_list, *trash_list);
}
}
static GSList *free_list = NULL;
static gboolean
allocate_from_known_page (void)
{
guint i, j, n_trials = N_PAGES * PAGE_SIZE / SAMPLE_SIZE; /* upper bound */
for (i = 0; i < n_trials; i++)
{
void *b = g_slice_alloc (SAMPLE_SIZE);
void *p = (void*) (PAGE_SIZE * ((gsize) b / PAGE_SIZE));
free_list = g_slist_prepend (free_list, b);
/* find page */
for (j = 0; j < N_PAGES; j++)
if (pages[j].page == p)
return TRUE;
}
return FALSE;
}
int
main (int argc,
char *argv[])
{
int j, n_pages = 0;
void *mps[N_MAGAZINE_PROBES];
/* probe some magazine sizes */
for (j = 0; j < N_MAGAZINE_PROBES; j++)
mps[j] = g_slice_alloc (magazine_probes[j]);
/* mps[*] now contains pointers to allocated slices */
/* allocate blocks from N_PAGES different pages */
while (n_pages < N_PAGES)
{
void *b = g_slice_alloc (SAMPLE_SIZE);
void *p = (void*) (PAGE_SIZE * ((gsize) b / PAGE_SIZE));
for (j = 0; j < N_PAGES; j++)
if (pages[j].page == p)
break;
if (j < N_PAGES) /* known page */
free_list = g_slist_prepend (free_list, b);
else /* new page */
{
j = n_pages++;
pages[j].page = p;
pages[j].sample = b;
}
}
/* release intermediate allocations */
release_trash_list (&free_list, SAMPLE_SIZE);
/* ensure that we can allocate from known pages */
if (!allocate_from_known_page())
g_error ("failed to allocate from magazine/page cache (before g_thread_init)");
/* release intermediate allocations */
release_trash_list (&free_list, SAMPLE_SIZE);
/* release magazine probes to be retained */
for (j = 0; j < N_MAGAZINE_PROBES; j++)
g_slice_free1 (magazine_probes[j], mps[j]);
/* mps[*] now contains pointers to releaed slices */
/* ensure probes were retained */
for (j = 0; j < N_MAGAZINE_PROBES; j++)
{
GSList *trash = NULL;
guint k;
for (k = 0; k < MAX_PROBE_TRIALS; k++)
{
void *mem = g_slice_alloc (magazine_probes[j]);
if (mem == mps[j])
break; /* reallocated previously freed slice */
trash = g_slist_prepend (trash, mem);
}
release_trash_list (&trash, magazine_probes[j]);
if (k >= MAX_PROBE_TRIALS) /* failed to reallocate slice */
g_error ("failed to reallocate slice from magazine (before g_thread_init): size=%d", magazine_probes[j]);
}
/* mps[*] now contains pointers to reallocated slices */
/* release magazine probes to be retained across g_thread_init */
for (j = 0; j < N_MAGAZINE_PROBES; j++)
g_slice_free1 (magazine_probes[j], mps[j]);
/* mps[*] now contains pointers to releaed slices */
/* initialize threading (should retain allocator state) */
g_thread_init (NULL);
/* ensure probes were retained */
for (j = 0; j < N_MAGAZINE_PROBES; j++)
{
GSList *trash = NULL;
guint k;
for (k = 0; k < MAX_PROBE_TRIALS; k++)
{
void *mem = g_slice_alloc (magazine_probes[j]);
if (mem == mps[j])
break; /* reallocated previously freed slice */
trash = g_slist_prepend (trash, mem);
}
release_trash_list (&trash, magazine_probes[j]);
if (k >= MAX_PROBE_TRIALS) /* failed to reallocate slice */
g_error ("failed to reallocate slice from magazine (after g_thread_init): size=%d", magazine_probes[j]);
}
/* mps[*] now contains pointers to reallocated slices */
/* ensure that we can allocate from known pages */
if (!allocate_from_known_page())
g_error ("failed to allocate from magazine/page cache (after g_thread_init)");
/* some cleanups */
for (j = 0; j < N_MAGAZINE_PROBES; j++)
g_slice_free1 (magazine_probes[j], mps[j]);
release_trash_list (&free_list, SAMPLE_SIZE);
return 0;
}