rototiller: pass num_cpus to .create_context()

Back in the day, there was no {create,destroy}_context(), so passing
num_cpus to just prepare_frame made sense.  Modules then would
implicitly initialize themselves on the first prepare_frame() call
using a static initialized variable.

Since then things have been decomposed a bit for more sophisticated
(and cleaner) modules.  It can be necessary to allocate per-cpu data
structures and the natural place to do that is @ create_context().  So
this commit wires that up.

A later commit will probably have to plumb a "current cpu" identifier
into the render_fragment() function.  Because a per-cpu data structure
isn't particularly useful if you can't easily address it from within
your execution context.

11 files changed, 18 insertions, 16 deletions

diff --git a/src/modules/flui2d/flui2d.c b/src/modules/flui2d/flui2d.c
index 65aeace..624202b 100644
--- a/src/modules/flui2d/flui2d.c
+++ b/src/modules/flui2d/flui2d.c
@@ -187,7 +187,7 @@ typedef struct flui2d_context_t {
 } flui2d_context_t;
 
 
-static void * flui2d_create_context(void)
+static void * flui2d_create_context(unsigned num_cpus)
 {
 	flui2d_context_t	*ctxt;
 
diff --git a/src/modules/julia/julia.c b/src/modules/julia/julia.c
index b35116b..61ed102 100644
--- a/src/modules/julia/julia.c
+++ b/src/modules/julia/julia.c
@@ -66,7 +66,7 @@ static uint32_t	colors[] = {
 		};
 
 
-static void * julia_create_context(void)
+static void * julia_create_context(unsigned num_cpus)
 {
 	return calloc(1, sizeof(julia_context_t));
 }
diff --git a/src/modules/plasma/plasma.c b/src/modules/plasma/plasma.c
index 245cf3c..731838f 100644
--- a/src/modules/plasma/plasma.c
+++ b/src/modules/plasma/plasma.c
@@ -47,7 +47,7 @@ static void init_plasma(int32_t *costab, int32_t *sintab)
 }
 
 
-static void * plasma_create_context(void)
+static void * plasma_create_context(unsigned num_cpus)
 {
 	return calloc(1, sizeof(plasma_context_t));
 }
diff --git a/src/modules/ray/ray.c b/src/modules/ray/ray.c
index c0c067e..99e6609 100644
--- a/src/modules/ray/ray.c
+++ b/src/modules/ray/ray.c
@@ -124,7 +124,7 @@ typedef struct ray_context_t {
 } ray_context_t;
 
 
-static void * ray_create_context(void)
+static void * ray_create_context(unsigned num_cpus)
 {
 	return calloc(1, sizeof(ray_context_t));
 }
diff --git a/src/modules/roto/roto.c b/src/modules/roto/roto.c
index c5c951d..050b129 100644
--- a/src/modules/roto/roto.c
+++ b/src/modules/roto/roto.c
@@ -32,7 +32,7 @@ static int32_t	costab[FIXED_TRIG_LUT_SIZE], sintab[FIXED_TRIG_LUT_SIZE];
 static uint8_t	texture[256][256];
 static color_t	palette[2];
 
-static void * roto_create_context(void)
+static void * roto_create_context(unsigned num_cpus)
 {
 	return calloc(1, sizeof(roto_context_t));
 }
diff --git a/src/modules/rtv/rtv.c b/src/modules/rtv/rtv.c
index c4c6dd2..dd9ece8 100644
--- a/src/modules/rtv/rtv.c
+++ b/src/modules/rtv/rtv.c
@@ -31,6 +31,7 @@
 typedef struct rtv_context_t {
 	const rototiller_module_t	**modules;
 	size_t				n_modules;
+	unsigned			n_cpus;
 
 	time_t				next_switch, next_hide_caption;
 	const rototiller_module_t	*module, *last_module;
@@ -41,7 +42,7 @@ typedef struct rtv_context_t {
 } rtv_context_t;
 
 static void setup_next_module(rtv_context_t *ctxt);
-static void * rtv_create_context(void);
+static void * rtv_create_context(unsigned num_cpus);
 static void rtv_destroy_context(void *context);
 static void rtv_prepare_frame(void *context, unsigned n_cpus, fb_fragment_t *fragment, rototiller_fragmenter_t *res_fragmenter);
 static void rtv_finish_frame(void *context, fb_fragment_t *fragment);
@@ -152,14 +153,15 @@ static void setup_next_module(rtv_context_t *ctxt)
 	}
 
 	if (ctxt->module->create_context)
-		ctxt->module_ctxt = ctxt->module->create_context();
+		ctxt->module_ctxt = ctxt->module->create_context(ctxt->n_cpus);
 }
 
 
-static void * rtv_create_context(void)
+static void * rtv_create_context(unsigned num_cpus)
 {
 	rtv_context_t	*ctxt = calloc(1, sizeof(rtv_context_t));
 
+	ctxt->n_cpus = num_cpus;
 	ctxt->snow_module = rototiller_lookup_module("snow");
 	rototiller_get_modules(&ctxt->modules, &ctxt->n_modules);
 	setup_next_module(ctxt);
diff --git a/src/modules/sparkler/sparkler.c b/src/modules/sparkler/sparkler.c
index 7ffa3d6..9462438 100644
--- a/src/modules/sparkler/sparkler.c
+++ b/src/modules/sparkler/sparkler.c
@@ -24,7 +24,7 @@ typedef struct sparkler_context_t {
 extern particle_ops_t	simple_ops;
 
 
-static void * sparkler_create_context(void)
+static void * sparkler_create_context(unsigned num_cpus)
 {
 	static int		initialized;
 	sparkler_context_t	*ctxt;
diff --git a/src/modules/submit/submit.c b/src/modules/submit/submit.c
index 3fc2ddd..340783c 100644
--- a/src/modules/submit/submit.c
+++ b/src/modules/submit/submit.c
@@ -261,7 +261,7 @@ static void setup_grid(submit_context_t *ctxt)
 }
 
 
-static void * submit_create_context(void)
+static void * submit_create_context(unsigned num_cpus)
 {
 	submit_context_t	*ctxt;
 
diff --git a/src/modules/swab/swab.c b/src/modules/swab/swab.c
index 6528900..aa53566 100644
--- a/src/modules/swab/swab.c
+++ b/src/modules/swab/swab.c
@@ -60,7 +60,7 @@ static inline uint32_t color_to_uint32(color_t color) {
 }
 
 
-static void * swab_create_context(void)
+static void * swab_create_context(unsigned num_cpus)
 {
 	swab_context_t	*ctxt;
 
diff --git a/src/rototiller.c b/src/rototiller.c
index 74ba006..a5d0927 100644
--- a/src/rototiller.c
+++ b/src/rototiller.c
@@ -416,13 +416,13 @@ int main(int argc, const char *argv[])
 	exit_if(!fps_setup(),
 		"unable to setup fps counter");
 
-	exit_if(rototiller.module->create_context &&
-		!(rototiller.module_context = rototiller.module->create_context()),
-		"unable to create module context");
-
 	pexit_if(!(rototiller.threads = threads_create()),
 		"unable to create rendering threads");
 
+	exit_if(rototiller.module->create_context &&
+		!(rototiller.module_context = rototiller.module->create_context(threads_num_threads(rototiller.threads))),
+		"unable to create module context");
+
 	pexit_if(pthread_create(&rototiller.thread, NULL, rototiller_thread, &rototiller) != 0,
 		"unable to create dispatch thread");
 
diff --git a/src/rototiller.h b/src/rototiller.h
index ca2559a..e60eece 100644
--- a/src/rototiller.h
+++ b/src/rototiller.h
@@ -11,7 +11,7 @@ typedef struct settings_t settings;
 typedef struct setting_desc_t setting_desc_t;
 
 typedef struct rototiller_module_t {
-	void *	(*create_context)(void);
+	void *	(*create_context)(unsigned n_cpus);
 	void	(*destroy_context)(void *context);
 	void	(*prepare_frame)(void *context, unsigned n_cpus, fb_fragment_t *fragment, rototiller_fragmenter_t *res_fragmenter);
 	void	(*render_fragment)(void *context, fb_fragment_t *fragment);