Make the shared memory segment size configurable

This is useful only on systems where memory overcommit is not available
or disabled.

src/pulsecore/conf-parser.c

@@ -166,6 +166,24 @@ int pa_config_parse_int(const char *filename, unsigned line, const char *lvalue,
     return 0;
 }
 
+int pa_config_parse_size(const char *filename, unsigned line, const char *lvalue, const char *rvalue, void *data, void *userdata) {
+    size_t *i = data;
+    uint32_t k;
+
+    pa_assert(filename);
+    pa_assert(lvalue);
+    pa_assert(rvalue);
+    pa_assert(data);
+
+    if (pa_atou(rvalue, &k) < 0) {
+        pa_log("[%s:%u] Failed to parse numeric value: %s", filename, line, rvalue);
+        return -1;
+    }
+
+    *i = (size_t) k;
+    return 0;
+}
+
 int pa_config_parse_bool(const char *filename, unsigned line, const char *lvalue, const char *rvalue, void *data, void *userdata) {
     int k;
     pa_bool_t *b = data;

src/pulsecore/conf-parser.h

@@ -39,8 +39,9 @@ typedef struct pa_config_item {
  * NULL */
 int pa_config_parse(const char *filename, FILE *f, const pa_config_item *t, void *userdata);
 
-/* Generic parsers for integers, booleans and strings */
+/* Generic parsers for integers, size_t, booleans and strings */
 int pa_config_parse_int(const char *filename, unsigned line, const char *lvalue, const char *rvalue, void *data, void *userdata);
+int pa_config_parse_size(const char *filename, unsigned line, const char *lvalue, const char *rvalue, void *data, void *userdata);
 int pa_config_parse_bool(const char *filename, unsigned line, const char *lvalue, const char *rvalue, void *data, void *userdata);
 int pa_config_parse_string(const char *filename, unsigned line, const char *lvalue, const char *rvalue, void *data, void *userdata);
 

src/pulsecore/core.c

@@ -66,7 +66,7 @@ static int core_process_msg(pa_msgobject *o, int code, void *userdata, int64_t o
 
 static void core_free(pa_object *o);
 
-pa_core* pa_core_new(pa_mainloop_api *m, int shared) {
+pa_core* pa_core_new(pa_mainloop_api *m, pa_bool_t shared, size_t shm_size) {
     pa_core* c;
     pa_mempool *pool;
     int j;
@@ -74,14 +74,14 @@ pa_core* pa_core_new(pa_mainloop_api *m, int shared) {
     pa_assert(m);
 
     if (shared) {
-        if (!(pool = pa_mempool_new(shared))) {
+        if (!(pool = pa_mempool_new(shared, shm_size))) {
             pa_log_warn("failed to allocate shared memory pool. Falling back to a normal memory pool.");
-            shared = 0;
+            shared = FALSE;
         }
     }
 
     if (!shared) {
-        if (!(pool = pa_mempool_new(shared))) {
+        if (!(pool = pa_mempool_new(shared, shm_size))) {
             pa_log("pa_mempool_new() failed.");
             return NULL;
         }

src/pulsecore/core.h

@@ -141,7 +141,7 @@ enum {
     PA_CORE_MESSAGE_MAX
 };
 
-pa_core* pa_core_new(pa_mainloop_api *m, int shared);
+pa_core* pa_core_new(pa_mainloop_api *m, pa_bool_t shared, size_t shm_size);
 
 /* Check whether noone is connected to this core */
 void pa_core_check_idle(pa_core *c);

src/pulsecore/memblock.c

@@ -680,8 +680,9 @@ static void memblock_replace_import(pa_memblock *b) {
         pa_mutex_unlock(seg->import->mutex);
 }
 
-pa_mempool* pa_mempool_new(pa_bool_t shared) {
+pa_mempool* pa_mempool_new(pa_bool_t shared, size_t size) {
     pa_mempool *p;
+    char t1[64], t2[64];
 
     p = pa_xnew(pa_mempool, 1);
 
@@ -692,13 +693,26 @@ pa_mempool* pa_mempool_new(pa_bool_t shared) {
     if (p->block_size < PA_PAGE_SIZE)
         p->block_size = PA_PAGE_SIZE;
 
-    p->n_blocks = PA_MEMPOOL_SLOTS_MAX;
+    if (size <= 0)
+        p->n_blocks = PA_MEMPOOL_SLOTS_MAX;
+    else {
+        p->n_blocks = (unsigned) (size / p->block_size);
+
+        if (p->n_blocks < 2)
+            p->n_blocks = 2;
+    }
 
     if (pa_shm_create_rw(&p->memory, p->n_blocks * p->block_size, shared, 0700) < 0) {
         pa_xfree(p);
         return NULL;
     }
 
+    pa_log_debug("Using %s memory pool with %u slots of size %s each, total size is %s",
+                 p->memory.shared ? "shared" : "private",
+                 p->n_blocks,
+                 pa_bytes_snprint(t1, sizeof(t1), (unsigned) p->block_size),
+                 pa_bytes_snprint(t2, sizeof(t2), (unsigned) (p->n_blocks * p->block_size)));
+
     memset(&p->stat, 0, sizeof(p->stat));
     pa_atomic_store(&p->n_init, 0);
 

src/pulsecore/memblock.h

@@ -117,7 +117,7 @@ pa_mempool * pa_memblock_get_pool(pa_memblock *b);
 pa_memblock *pa_memblock_will_need(pa_memblock *b);
 
 /* The memory block manager */
-pa_mempool* pa_mempool_new(pa_bool_t shared);
+pa_mempool* pa_mempool_new(pa_bool_t shared, size_t size);
 void pa_mempool_free(pa_mempool *p);
 const pa_mempool_stat* pa_mempool_get_stat(pa_mempool *p);
 void pa_mempool_vacuum(pa_mempool *p);