From e2287f35db7504f85334884efa038abe7c7a6a8e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Barnab=C3=A1s=20P=C5=91cze?= <pobrn@protonmail.com>
Date: Sat, 19 Feb 2022 15:12:31 +0100
Subject: [PATCH] spa: support: loop: move struct members

Move the boolean members of `struct source_impl` to the end
of the struct. This changes the size of the struct from
104 bytes to 96 bytes on x86-64.

Before:

struct source_impl {
        struct spa_source          source;               /*     0    48 */
        struct impl *              impl;                 /*    48     8 */
        struct spa_list            link;                 /*    56    16 */
        /* --- cacheline 1 boundary (64 bytes) was 8 bytes ago --- */
        _Bool                      close;                /*    72     1 */

        /* XXX 7 bytes hole, try to pack */

        union {
                spa_source_io_func_t io;                 /*    80     8 */
                spa_source_idle_func_t idle;             /*    80     8 */
                spa_source_event_func_t event;           /*    80     8 */
                spa_source_timer_func_t timer;           /*    80     8 */
                spa_source_signal_func_t signal;         /*    80     8 */
        } func;                                          /*    80     8 */
        _Bool                      enabled;              /*    88     1 */

        /* XXX 7 bytes hole, try to pack */

        struct spa_source *        fallback;             /*    96     8 */

        /* size: 104, cachelines: 2, members: 7 */
        /* sum members: 90, holes: 2, sum holes: 14 */
        /* last cacheline: 40 bytes */
};

After:

struct source_impl {
        struct spa_source          source;               /*     0    48 */
        struct impl *              impl;                 /*    48     8 */
        struct spa_list            link;                 /*    56    16 */
        /* --- cacheline 1 boundary (64 bytes) was 8 bytes ago --- */
        union {
                spa_source_io_func_t io;                 /*    72     8 */
                spa_source_idle_func_t idle;             /*    72     8 */
                spa_source_event_func_t event;           /*    72     8 */
                spa_source_timer_func_t timer;           /*    72     8 */
                spa_source_signal_func_t signal;         /*    72     8 */
        } func;                                          /*    72     8 */
        struct spa_source *        fallback;             /*    80     8 */
        _Bool                      close;                /*    88     1 */
        _Bool                      enabled;              /*    89     1 */

        /* size: 96, cachelines: 2, members: 7 */
        /* padding: 6 */
        /* last cacheline: 32 bytes */
};
---
 spa/plugins/support/loop.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/spa/plugins/support/loop.c b/spa/plugins/support/loop.c
index 04739eb2a..444b57028 100644
--- a/spa/plugins/support/loop.c
+++ b/spa/plugins/support/loop.c
@@ -98,7 +98,6 @@ struct source_impl {
 	struct impl *impl;
 	struct spa_list link;
 
-	bool close;
 	union {
 		spa_source_io_func_t io;
 		spa_source_idle_func_t idle;
@@ -106,8 +105,11 @@ struct source_impl {
 		spa_source_timer_func_t timer;
 		spa_source_signal_func_t signal;
 	} func;
-	bool enabled;
+
 	struct spa_source *fallback;
+
+	bool close;
+	bool enabled;
 };
 /** \endcond */