X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=libringbuffer%2Fbackend.h;h=46022ad3c5767d7f46db917ee41d2f6e72a98c7b;hb=c7667bfebfa1d054ad8d54fd98ada3c86184e327;hp=53a97140bf33bfd70c21f6b7939c1f48251cb20f;hpb=a44c74d96a15230cec7c09c770bf7fc745f0df15;p=lttng-ust.git

diff --git a/libringbuffer/backend.h b/libringbuffer/backend.h
index 53a97140..46022ad3 100644
--- a/libringbuffer/backend.h
+++ b/libringbuffer/backend.h
@@ -71,37 +71,33 @@ lib_ring_buffer_read_offset_address(struct lttng_ust_lib_ring_buffer_backend *bu
  * backend-specific memcpy() operation. Calls the slow path (_ring_buffer_write)
  * if copy is crossing a page boundary.
  */
-static inline
+static inline __attribute__((always_inline))
 void lib_ring_buffer_write(const struct lttng_ust_lib_ring_buffer_config *config,
 			   struct lttng_ust_lib_ring_buffer_ctx *ctx,
 			   const void *src, size_t len)
 {
-	struct lttng_ust_lib_ring_buffer_backend *bufb = &ctx->buf->backend;
 	struct channel_backend *chanb = &ctx->chan->backend;
 	struct lttng_ust_shm_handle *handle = ctx->handle;
-	size_t sbidx;
 	size_t offset = ctx->buf_offset;
-	struct lttng_ust_lib_ring_buffer_backend_pages_shmp *rpages;
-	unsigned long sb_bindex, id;
+	struct lttng_ust_lib_ring_buffer_backend_pages *backend_pages;
+	void *p;
 
 	if (caa_unlikely(!len))
 		return;
-	offset &= chanb->buf_size - 1;
-	sbidx = offset >> chanb->subbuf_size_order;
-	id = shmp_index(handle, bufb->buf_wsb, sbidx)->id;
-	sb_bindex = subbuffer_id_get_index(config, id);
-	rpages = shmp_index(handle, bufb->array, sb_bindex);
-	CHAN_WARN_ON(ctx->chan,
-		     config->mode == RING_BUFFER_OVERWRITE
-		     && subbuffer_id_is_noref(config, id));
 	/*
 	 * Underlying layer should never ask for writes across
 	 * subbuffers.
 	 */
-	CHAN_WARN_ON(chanb, offset >= chanb->buf_size);
-	lib_ring_buffer_do_copy(config,
-				shmp_index(handle, shmp(handle, rpages->shmp)->p, offset & (chanb->subbuf_size - 1)),
-				src, len);
+	CHAN_WARN_ON(chanb, (offset & (chanb->buf_size - 1)) + len > chanb->buf_size);
+	backend_pages = lib_ring_buffer_get_backend_pages_from_ctx(config, ctx);
+	if (caa_unlikely(!backend_pages)) {
+		if (lib_ring_buffer_backend_get_pages(config, ctx, &backend_pages))
+			return;
+	}
+	p = shmp_index(handle, backend_pages->p, offset & (chanb->subbuf_size - 1));
+	if (caa_unlikely(!p))
+		return;
+	lib_ring_buffer_do_copy(config, p, src, len);
 	ctx->buf_offset += len;
 }
 
@@ -110,7 +106,7 @@ void lib_ring_buffer_write(const struct lttng_ust_lib_ring_buffer_config *config
  * terminating character is found in @src. Returns the number of bytes
  * copied. Does *not* terminate @dest with NULL terminating character.
  */
-static inline
+static inline __attribute__((always_inline))
 size_t lib_ring_buffer_do_strcpy(const struct lttng_ust_lib_ring_buffer_config *config,
 		char *dest, const char *src, size_t len)
 {
@@ -146,52 +142,51 @@ size_t lib_ring_buffer_do_strcpy(const struct lttng_ust_lib_ring_buffer_config *
  * character is found in @src before @len - 1 characters are copied, pad
  * the buffer with @pad characters (e.g. '#').
  */
-static inline
+static inline __attribute__((always_inline))
 void lib_ring_buffer_strcpy(const struct lttng_ust_lib_ring_buffer_config *config,
 			   struct lttng_ust_lib_ring_buffer_ctx *ctx,
 			   const char *src, size_t len, int pad)
 {
-	struct lttng_ust_lib_ring_buffer_backend *bufb = &ctx->buf->backend;
 	struct channel_backend *chanb = &ctx->chan->backend;
 	struct lttng_ust_shm_handle *handle = ctx->handle;
-	size_t sbidx, count;
+	size_t count;
 	size_t offset = ctx->buf_offset;
-	struct lttng_ust_lib_ring_buffer_backend_pages_shmp *rpages;
-	unsigned long sb_bindex, id;
+	struct lttng_ust_lib_ring_buffer_backend_pages *backend_pages;
+	void *p;
 
 	if (caa_unlikely(!len))
 		return;
-	offset &= chanb->buf_size - 1;
-	sbidx = offset >> chanb->subbuf_size_order;
-	id = shmp_index(handle, bufb->buf_wsb, sbidx)->id;
-	sb_bindex = subbuffer_id_get_index(config, id);
-	rpages = shmp_index(handle, bufb->array, sb_bindex);
-	CHAN_WARN_ON(ctx->chan,
-		     config->mode == RING_BUFFER_OVERWRITE
-		     && subbuffer_id_is_noref(config, id));
 	/*
 	 * Underlying layer should never ask for writes across
 	 * subbuffers.
 	 */
-	CHAN_WARN_ON(chanb, offset >= chanb->buf_size);
-	count = lib_ring_buffer_do_strcpy(config,
-			shmp_index(handle, shmp(handle, rpages->shmp)->p,
-				offset & (chanb->subbuf_size - 1)),
-			src, len - 1);
+	CHAN_WARN_ON(chanb, (offset & (chanb->buf_size - 1)) + len > chanb->buf_size);
+	backend_pages = lib_ring_buffer_get_backend_pages_from_ctx(config, ctx);
+	if (caa_unlikely(!backend_pages)) {
+		if (lib_ring_buffer_backend_get_pages(config, ctx, &backend_pages))
+			return;
+	}
+	p = shmp_index(handle, backend_pages->p, offset & (chanb->subbuf_size - 1));
+	if (caa_unlikely(!p))
+		return;
+
+	count = lib_ring_buffer_do_strcpy(config, p, src, len - 1);
 	offset += count;
 	/* Padding */
 	if (caa_unlikely(count < len - 1)) {
 		size_t pad_len = len - 1 - count;
 
-		lib_ring_buffer_do_memset(shmp_index(handle, shmp(handle, rpages->shmp)->p,
-				offset & (chanb->subbuf_size - 1)),
-			pad, pad_len);
+		p = shmp_index(handle, backend_pages->p, offset & (chanb->subbuf_size - 1));
+		if (caa_unlikely(!p))
+			return;
+		lib_ring_buffer_do_memset(p, pad, pad_len);
 		offset += pad_len;
 	}
 	/* Final '\0' */
-	lib_ring_buffer_do_memset(shmp_index(handle, shmp(handle, rpages->shmp)->p,
-				offset & (chanb->subbuf_size - 1)),
-			'\0', 1);
+	p = shmp_index(handle, backend_pages->p, offset & (chanb->subbuf_size - 1));
+	if (caa_unlikely(!p))
+		return;
+	lib_ring_buffer_do_memset(p, '\0', 1);
 	ctx->buf_offset += len;
 }
 
@@ -207,21 +202,42 @@ unsigned long lib_ring_buffer_get_records_unread(
 				struct lttng_ust_shm_handle *handle)
 {
 	struct lttng_ust_lib_ring_buffer_backend *bufb = &buf->backend;
-	struct lttng_ust_lib_ring_buffer_backend_pages_shmp *pages;
-	unsigned long records_unread = 0, sb_bindex, id;
+	unsigned long records_unread = 0, sb_bindex;
 	unsigned int i;
-
-	for (i = 0; i < shmp(handle, bufb->chan)->backend.num_subbuf; i++) {
-		id = shmp_index(handle, bufb->buf_wsb, i)->id;
-		sb_bindex = subbuffer_id_get_index(config, id);
-		pages = shmp_index(handle, bufb->array, sb_bindex);
-		records_unread += v_read(config, &shmp(handle, pages->shmp)->records_unread);
+	struct channel *chan;
+
+	chan = shmp(handle, bufb->chan);
+	if (!chan)
+		return 0;
+	for (i = 0; i < chan->backend.num_subbuf; i++) {
+		struct lttng_ust_lib_ring_buffer_backend_subbuffer *wsb;
+		struct lttng_ust_lib_ring_buffer_backend_pages_shmp *rpages;
+		struct lttng_ust_lib_ring_buffer_backend_pages *backend_pages;
+
+		wsb = shmp_index(handle, bufb->buf_wsb, i);
+		if (!wsb)
+			return 0;
+		sb_bindex = subbuffer_id_get_index(config, wsb->id);
+		rpages = shmp_index(handle, bufb->array, sb_bindex);
+		if (!rpages)
+			return 0;
+		backend_pages = shmp(handle, rpages->shmp);
+		if (!backend_pages)
+			return 0;
+		records_unread += v_read(config, &backend_pages->records_unread);
 	}
 	if (config->mode == RING_BUFFER_OVERWRITE) {
-		id = bufb->buf_rsb.id;
-		sb_bindex = subbuffer_id_get_index(config, id);
-		pages = shmp_index(handle, bufb->array, sb_bindex);
-		records_unread += v_read(config, &shmp(handle, pages->shmp)->records_unread);
+		struct lttng_ust_lib_ring_buffer_backend_pages_shmp *rpages;
+		struct lttng_ust_lib_ring_buffer_backend_pages *backend_pages;
+
+		sb_bindex = subbuffer_id_get_index(config, bufb->buf_rsb.id);
+		rpages = shmp_index(handle, bufb->array, sb_bindex);
+		if (!rpages)
+			return 0;
+		backend_pages = shmp(handle, rpages->shmp);
+		if (!backend_pages)
+			return 0;
+		records_unread += v_read(config, &backend_pages->records_unread);
 	}
 	return records_unread;
 }