[PATCH] blktrace: add -s sendfile option (doesn't work right now)

diff --git a/blktrace.c b/blktrace.c
index d61b2d9d2fd9623d5e8bc3842ff568439c7ca427..23f7fc3af2eda89963c7ec3de8b2e7ff18853a6f 100644 (file)
--- a/blktrace.c
+++ b/blktrace.c
@@ -41,6 +41,7 @@
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include <netdb.h>
+#include <sys/sendfile.h>
 
 #include "blktrace.h"
 #include "barrier.h"
@@ -58,7 +59,7 @@ static char blktrace_version[] = "0.99";
 
 #define RELAYFS_TYPE   0xF0B4A981
 
-#define S_OPTS "d:a:A:r:o:kw:Vb:n:D:lh:p:"
+#define S_OPTS "d:a:A:r:o:kw:Vb:n:D:lh:p:s"
 static struct option l_opts[] = {
        {
                .name = "dev",
@@ -144,6 +145,12 @@ static struct option l_opts[] = {
                .flag = NULL,
                .val = 'p'
        },
+       {
+               .name = "sendfile",
+               .has_arg = no_argument,
+               .flag = NULL,
+               .val = 's'
+       },
        {
                .name = NULL,
        }
@@ -153,6 +160,7 @@ struct tip_subbuf {
        void *buf;
        unsigned int len;
        unsigned int max_len;
+       off_t offset;
 };
 
 #define FIFO_SIZE      (1024)  /* should be plenty big! */
@@ -174,6 +182,7 @@ struct thread_information {
 
        FILE *ofile;
        char *ofile_buffer;
+       off_t ofile_offset;
        int ofile_stdout;
        int ofile_mmap;
 
@@ -276,6 +285,7 @@ enum {
 static char hostname[MAXHOSTNAMELEN];
 static int net_port = TRACE_NET_PORT;
 static int net_mode = 0;
+static int net_sendfile;
 
 static int net_in_fd = -1;
 static int net_out_fd = -1;
@@ -525,6 +535,28 @@ static int mmap_subbuf(struct thread_information *tip, unsigned int maxlen)
        return -1;
 }
 
+static int get_subbuf_sendfile(struct thread_information *tip,
+                              unsigned int maxlen)
+{
+       struct tip_subbuf *ts = malloc(sizeof(*ts));
+       struct stat sb;
+
+       ts->buf = malloc(buf_size);
+       ts->max_len = maxlen;
+       ts->buf = NULL;
+
+       if (fstat(tip->fd, &sb) < 0) {
+               perror("trace stat");
+               return 1;
+       }
+
+       ts->len = sb.st_size - tip->ofile_offset;
+       ts->max_len = ts->len;
+       ts->offset = tip->ofile_offset;
+       tip->ofile_offset += ts->len;
+       return subbuf_fifo_queue(tip, ts);
+}
+
 /*
  * Use the copy approach for pipes and network
  */
@@ -630,8 +662,7 @@ static int write_data_net(int fd, void *buf, unsigned int buf_len)
        return 0;
 }
 
-static int flush_subbuf_net(struct thread_information *tip,
-                           struct tip_subbuf *ts)
+static int net_send_header(struct thread_information *tip, unsigned int len)
 {
        struct blktrace_net_hdr hdr;
 
@@ -639,11 +670,16 @@ static int flush_subbuf_net(struct thread_information *tip,
        strcpy(hdr.buts_name, tip->device->buts_name);
        hdr.cpu = tip->cpu;
        hdr.max_cpus = ncpus;
-       hdr.len = ts->len;
+       hdr.len = len;
 
-       if (write_data_net(net_out_fd, &hdr, sizeof(hdr)))
-               return 1;
+       return write_data_net(net_out_fd, &hdr, sizeof(hdr));
+}
 
+static int flush_subbuf_net(struct thread_information *tip,
+                           struct tip_subbuf *ts)
+{
+       if (net_send_header(tip, ts->len))
+               return 1;
        if (write_data_net(net_out_fd, ts->buf, ts->len))
                return 1;
 
@@ -652,6 +688,20 @@ static int flush_subbuf_net(struct thread_information *tip,
        return 0;
 }
 
+static int flush_subbuf_sendfile(struct thread_information *tip,
+                                struct tip_subbuf *ts)
+{
+       if (net_send_header(tip, ts->len))
+               return 1;
+       if (sendfile(net_out_fd, tip->fd, &ts->offset, ts->len) < 0) {
+               perror("sendfile");
+               return 1;
+       }
+
+       free(ts);
+       return 0;
+}
+
 static int write_data(struct thread_information *tip, void *buf,
                      unsigned int buf_len)
 {
@@ -837,16 +887,23 @@ static void fill_ops(struct thread_information *tip)
        /*
         * setup ops
         */
-       if (tip->ofile_mmap && net_mode != Net_client)
-               tip->get_subbuf = mmap_subbuf;
-       else
-               tip->get_subbuf = get_subbuf;
+       if (net_mode == Net_client) {
+               if (net_sendfile) {
+                       tip->get_subbuf = get_subbuf_sendfile;
+                       tip->flush_subbuf = flush_subbuf_sendfile;
+               } else {
+                       tip->get_subbuf = get_subbuf;
+                       tip->flush_subbuf = flush_subbuf_net;
+               }
+       } else {
+               if (tip->ofile_mmap)
+                       tip->get_subbuf = mmap_subbuf;
+               else
+                       tip->get_subbuf = get_subbuf;
 
-       if (net_mode == Net_client)
-               tip->flush_subbuf = flush_subbuf_net;
-       else
                tip->flush_subbuf = flush_subbuf_file;
-
+       }
+                       
        if (net_mode == Net_server)
                tip->read_data = read_data_net;
        else
@@ -1394,6 +1451,9 @@ int main(int argc, char *argv[])
                case 'p':
                        net_port = atoi(optarg);
                        break;
+               case 's':
+                       net_sendfile = 1;
+                       break;
                default:
                        show_usage(argv[0]);
                        return 1;