do O(1) instead of O(n) atomic operations in register functions

about 1ms faster startup time

Michael Niedermayer committed 12 years ago

Commit 133fbfc1 parent 2b215f33 files · +6 −5Browse files

Unified · Split

3 files

libavcodec/utils.c +3 −2
libavfilter/avfilter.c +1 −1
libavformat/format.c +2 −2

libavcodec/utils.c+3−2

@@ -206,7 +206,8 @@ av_cold void avcodec_register(AVCodec *codec) · 205 unmodified lines
206	avcodec_init();	206	avcodec_init();
207	p = &first_avcodec;	207	p = &first_avcodec;
208	codec->next = NULL;	208	codec->next = NULL;
209	while(avpriv_atomic_ptr_cas((void * volatile *)p, NULL, codec))	209
		210	while(p \|\| avpriv_atomic_ptr_cas((void volatile *)p, NULL, codec))
210	p = &(*p)->next;	211	p = &(*p)->next;
211		212
212	if (codec->init_static_data)	213	if (codec->init_static_data)
@@ -3191,7 +3192,7 @@ void av_register_hwaccel(AVHWAccel *hwaccel) · 2978 unmodified lines
3191	{	3192	{
3192	AVHWAccel **p = &first_hwaccel;	3193	AVHWAccel **p = &first_hwaccel;
3193	hwaccel->next = NULL;	3194	hwaccel->next = NULL;
3194	while(avpriv_atomic_ptr_cas((void * volatile *)p, NULL, hwaccel))	3195	while(p \|\| avpriv_atomic_ptr_cas((void volatile *)p, NULL, hwaccel))
3195	p = &(*p)->next;	3196	p = &(*p)->next;
3196	}	3197	}
3197		3198

libavfilter/avfilter.c+1−1

@@ -490,7 +490,7 @@ int avfilter_register(AVFilter *filter) · 489 unmodified lines
490		490
491	filter->next = NULL;	491	filter->next = NULL;
492		492
493	while(avpriv_atomic_ptr_cas((void * volatile *)f, NULL, filter))	493	while(f \|\| avpriv_atomic_ptr_cas((void volatile *)f, NULL, filter))
494	f = &(*f)->next;	494	f = &(*f)->next;
495		495
496	return 0;	496	return 0;

libavformat/format.c+2−2

@@ -54,7 +54,7 @@ void av_register_input_format(AVInputFormat *format) · 53 unmodified lines
54	AVInputFormat **p = &first_iformat;	54	AVInputFormat **p = &first_iformat;
55		55
56	format->next = NULL;	56	format->next = NULL;
57	while(avpriv_atomic_ptr_cas((void * volatile *)p, NULL, format))	57	while(p \|\| avpriv_atomic_ptr_cas((void volatile *)p, NULL, format))
58	p = &(*p)->next;	58	p = &(*p)->next;
59	}	59	}
60		60
@@ -63,7 +63,7 @@ void av_register_output_format(AVOutputFormat *format) · 2 unmodified lines
63	AVOutputFormat **p = &first_oformat;	63	AVOutputFormat **p = &first_oformat;
64		64
65	format->next = NULL;	65	format->next = NULL;
66	while(avpriv_atomic_ptr_cas((void * volatile *)p, NULL, format))	66	while(p \|\| avpriv_atomic_ptr_cas((void volatile *)p, NULL, format))
67	p = &(*p)->next;	67	p = &(*p)->next;
68	}	68	}
69		69