X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=ustd%2Flowlevel.c;fp=ustd%2Flowlevel.c;h=f386089e21b54f9c1a0b98cc351d26084deed454;hb=0b0cd93782698872ea4778d29cd68091663ca367;hp=0000000000000000000000000000000000000000;hpb=0ce2af7f6372336d520847b4745da781344ba743;p=ust.git

diff --git a/ustd/lowlevel.c b/ustd/lowlevel.c
new file mode 100644
index 0000000..f386089
--- /dev/null
+++ b/ustd/lowlevel.c
@@ -0,0 +1,50 @@
+#include "tracer.h"
+#include "ustd.h"
+#include "localerr.h"
+
+#define USTD_BUFFER_TRUNC(offset, bufinfo) \
+	((offset) & (~(((bufinfo)->subbuf_size*(bufinfo)->n_subbufs)-1)))
+
+void finish_consuming_dead_subbuffer(struct buffer_info *buf)
+{
+	struct ltt_channel_buf_struct *ltt_buf = buf->bufstruct_mem;
+
+	long write_offset = local_read(&ltt_buf->offset);
+	long consumed_offset = atomic_long_read(&ltt_buf->consumed);
+
+	long i_subbuf;
+
+	DBG("processing died buffer");
+	DBG("consumed offset is %ld", consumed_offset);
+	DBG("write offset is %ld", write_offset);
+
+	long first_subbuf = write_offset / buf->subbuf_size;
+	long last_subbuf = consumed_offset / buf->subbuf_size;
+
+	if(last_subbuf - first_subbuf > buf->n_subbufs) {
+		DBG("an overflow has occurred, nothing can be recovered");
+		return;
+	}
+
+	for(i_subbuf=first_subbuf; ; i_subbuf++, i_subbuf %= buf->n_subbufs) {
+		long commit_count = local_read(&ltt_buf->commit_count[i_subbuf]);
+
+		unsigned long valid_length = buf->subbuf_size;
+		long n_subbufs_order = get_count_order(buf->n_subbufs);
+		long commit_count_mask = (~0UL >> n_subbufs_order);
+
+		/* check if subbuf was fully written */
+		if (((commit_count - buf->subbuf_size) & commit_count_mask)
+		    - (USTD_BUFFER_TRUNC(consumed_offset, buf) >> n_subbufs_order)
+		    != 0) {
+			struct ltt_subbuffer_header *header = (struct ltt_subbuffer_header *)((char *)buf->mem)+i_subbuf*buf->subbuf_size;
+			valid_length = buf->subbuf_size - header->lost_size;
+		}
+
+		patient_write(buf->file_fd, buf->mem + i_subbuf * buf->subbuf_size, buf->subbuf_size);
+
+		if(i_subbuf == last_subbuf)
+			break;
+	}
+}
+