X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=libringbuffer%2Ffrontend_api.h;h=140159739feebc954f68d39b33806e3778f4ca01;hb=c7667bfebfa1d054ad8d54fd98ada3c86184e327;hp=5ddb8ac460951f0bae59a3f098cf6bca510a3799;hpb=f52a5702dbeb8125ca373ba363b29cbff3042cc1;p=lttng-ust.git

diff --git a/libringbuffer/frontend_api.h b/libringbuffer/frontend_api.h
index 5ddb8ac4..14015973 100644
--- a/libringbuffer/frontend_api.h
+++ b/libringbuffer/frontend_api.h
@@ -167,6 +167,8 @@ int lib_ring_buffer_reserve(const struct lttng_ust_lib_ring_buffer_config *confi
 		buf = shmp(handle, chan->backend.buf[ctx->cpu].shmp);
 	else
 		buf = shmp(handle, chan->backend.buf[0].shmp);
+	if (caa_unlikely(!buf))
+		return -EIO;
 	if (caa_unlikely(uatomic_read(&buf->record_disabled)))
 		return -EAGAIN;
 	ctx->buf = buf;
@@ -250,11 +252,16 @@ void lib_ring_buffer_commit(const struct lttng_ust_lib_ring_buffer_config *confi
 	unsigned long offset_end = ctx->buf_offset;
 	unsigned long endidx = subbuf_index(offset_end - 1, chan);
 	unsigned long commit_count;
+	struct commit_counters_hot *cc_hot = shmp_index(handle,
+						buf->commit_hot, endidx);
+
+	if (caa_unlikely(!cc_hot))
+		return;
 
 	/*
 	 * Must count record before incrementing the commit count.
 	 */
-	subbuffer_count_record(config, &buf->backend, endidx, handle);
+	subbuffer_count_record(config, ctx, &buf->backend, endidx, handle);
 
 	/*
 	 * Order all writes to buffer before the commit count update that will
@@ -262,7 +269,7 @@ void lib_ring_buffer_commit(const struct lttng_ust_lib_ring_buffer_config *confi
 	 */
 	cmm_smp_wmb();
 
-	v_add(config, ctx->slot_size, &shmp_index(handle, buf->commit_hot, endidx)->cc);
+	v_add(config, ctx->slot_size, &cc_hot->cc);
 
 	/*
 	 * commit count read can race with concurrent OOO commit count updates.
@@ -282,7 +289,7 @@ void lib_ring_buffer_commit(const struct lttng_ust_lib_ring_buffer_config *confi
 	 *   count reaches back the reserve offset for a specific sub-buffer,
 	 *   which is completely independent of the order.
 	 */
-	commit_count = v_read(config, &shmp_index(handle, buf->commit_hot, endidx)->cc);
+	commit_count = v_read(config, &cc_hot->cc);
 
 	lib_ring_buffer_check_deliver(config, buf, chan, offset_end - 1,
 				      commit_count, endidx, handle, ctx->tsc);
@@ -290,8 +297,8 @@ void lib_ring_buffer_commit(const struct lttng_ust_lib_ring_buffer_config *confi
 	 * Update used size at each commit. It's needed only for extracting
 	 * ring_buffer buffers from vmcore, after crash.
 	 */
-	lib_ring_buffer_write_commit_counter(config, buf, chan, endidx,
-			offset_end, commit_count, handle);
+	lib_ring_buffer_write_commit_counter(config, buf, chan,
+			offset_end, commit_count, handle, cc_hot);
 }
 
 /**