VP8: allow thread count changes

Fix the TODO(https://crbug.com/1486441) comment in vp8/vp8_cx_iface.c.

Make vp8cx_create_encoder_threads() work after it has been called
before. If there are already the exact number of threads it needs to
create, return immediately. Otherwise, shut down the existing threads
(by calling vp8cx_remove_encoder_threads()) and create the required
number of threads.

Call vp8cx_create_encoder_threads() in vp8e_set_config() to respond to
changes in g_threads or g_w (which also affects the number of threads
through cm->mb_cols and cpi->mt_sync_range).

Change-Id: I552eeca5b1f1f5313f59559eb1da396f270a2429

diff --git a/vp8/encoder/ethreading.c b/vp8/encoder/ethreading.c
index 3362755..9993905 100644 (file)
--- a/vp8/encoder/ethreading.c
+++ b/vp8/encoder/ethreading.c
@@ -487,15 +487,10 @@ void vp8cx_init_mbrthread_data(VP8_COMP *cpi, MACROBLOCK *x,
 
 int vp8cx_create_encoder_threads(VP8_COMP *cpi) {
   const VP8_COMMON *cm = &cpi->common;
-
-  vpx_atomic_init(&cpi->b_multi_threaded, 0);
-  cpi->encoding_thread_count = 0;
-  cpi->b_lpf_running = 0;
+  int th_count = 0;
 
   if (cm->processor_core_count > 1 && cpi->oxcf.multi_threaded > 1) {
-    int ithread;
-    int th_count = cpi->oxcf.multi_threaded - 1;
-    int rc = 0;
+    th_count = cpi->oxcf.multi_threaded - 1;
 
     /* don't allocate more threads than cores available */
     if (cpi->oxcf.multi_threaded > cm->processor_core_count) {
@@ -507,8 +502,13 @@ int vp8cx_create_encoder_threads(VP8_COMP *cpi) {
     if (th_count > ((cm->mb_cols / cpi->mt_sync_range) - 1)) {
       th_count = (cm->mb_cols / cpi->mt_sync_range) - 1;
     }
+  }
+  if (th_count == cpi->encoding_thread_count) return 0;
 
-    if (th_count == 0) return 0;
+  vp8cx_remove_encoder_threads(cpi);
+  if (th_count != 0) {
+    int ithread;
+    int rc = 0;
 
     CHECK_MEM_ERROR(&cpi->common.error, cpi->h_encoding_thread,
                     vpx_malloc(sizeof(pthread_t) * th_count));

diff --git a/vp8/vp8_cx_iface.c b/vp8/vp8_cx_iface.c
index 470fe9e..20c44ff 100644 (file)
--- a/vp8/vp8_cx_iface.c
+++ b/vp8/vp8_cx_iface.c
@@ -19,6 +19,9 @@
 #include "vpx_ports/static_assert.h"
 #include "vpx_ports/system_state.h"
 #include "vpx_util/vpx_timestamp.h"
+#if CONFIG_MULTITHREAD
+#include "vp8/encoder/ethreading.h"
+#endif
 #include "vp8/encoder/onyx_int.h"
 #include "vpx/vp8cx.h"
 #include "vp8/encoder/firstpass.h"
@@ -488,8 +491,9 @@ static vpx_codec_err_t vp8e_set_config(vpx_codec_alg_priv_t *ctx,
   ctx->cfg = *cfg;
   set_vp8e_config(&ctx->oxcf, ctx->cfg, ctx->vp8_cfg, NULL);
   vp8_change_config(ctx->cpi, &ctx->oxcf);
-  // TODO(https://crbug.com/1486441): Change thread counts;
-  // vp8cx_create_encoder_threads() is called once in vp8_create_compressor().
+#if CONFIG_MULTITHREAD
+  if (vp8cx_create_encoder_threads(ctx->cpi)) return VPX_CODEC_ERROR;
+#endif
   ctx->cpi->common.error.setjmp = 0;
   return VPX_CODEC_OK;
 }