From af8671792d05d52df78ea3a26e182fffe7b37a94 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Thu, 15 Mar 2007 08:47:28 +0000 Subject: [PATCH] Replace a g_slist_prepend/g_slist_remove pair with an on-stack link and 2007-03-15 Chris Wilson * glib/gmain.c (g_main_dispatch): Replace a g_slist_prepend/g_slist_remove pair with an on-stack link and open coding. (#416094) svn path=/trunk/; revision=5407 --- ChangeLog | 6 ++++++ glib/gmain.c | 17 +++++++++++++++-- 2 files changed, 21 insertions(+), 2 deletions(-) diff --git a/ChangeLog b/ChangeLog index 2347656..6212cbe 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2007-03-15 Chris Wilson + + * glib/gmain.c (g_main_dispatch): Replace a + g_slist_prepend/g_slist_remove pair with an on-stack link + and open coding. (#416094) + 2007-03-15 Matthias Clasen * glib/gscanner.[hc]: Some optimizations, use a lookup diff --git a/glib/gmain.c b/glib/gmain.c index 0bbd30f..a273cd3 100644 --- a/glib/gmain.c +++ b/glib/gmain.c @@ -2025,6 +2025,7 @@ g_main_dispatch (GMainContext *context) gboolean (*dispatch) (GSource *, GSourceFunc, gpointer); + GSList current_source_link; dispatch = source->source_funcs->dispatch; cb_funcs = source->callback_funcs; @@ -2045,11 +2046,23 @@ g_main_dispatch (GMainContext *context) UNLOCK_CONTEXT (context); current->depth++; - current->source = g_slist_prepend (current->source, source); + /* The on-stack allocation of the GSList is unconventional, but + * we know that the lifetime of the link is bounded to this + * function as the link is kept in a thread specific list and + * not manipulated outside of this function and its descendants. + * Avoiding the overhead of a g_slist_alloc() is useful as many + * applications do little more than dispatch events. + * + * This is a performance hack - do not revert to g_slist_prepend()! + */ + current_source_link.data = source; + current_source_link.next = current->source; + current->source = ¤t_source_link; need_destroy = ! dispatch (source, callback, user_data); - current->source = g_slist_remove (current->source, source); + g_assert (current->source == ¤t_source_link); + current->source = current_source_link.next; current->depth--; if (cb_funcs) -- 2.7.4