[Qemu-devel] [PATCH] Simple performance logging and network limiting based on trace option

[Harald Schieche <rehs@gmx.de>]

diff --git a/block/raw-posix.c b/block/raw-posix.c
index 475cf74..3c5cc71 100644
--- a/block/raw-posix.c
+++ b/block/raw-posix.c
@@ -1031,6 +1031,27 @@ static int aio_worker(void *arg)
     return ret;
 }
 
+static void log_guest_storage_performance(void)
+{
+    /*
+     * Performance logging isn't specified yet.
+     * Therefore we're using existing tracing.
+     */
+    static int64_t logged_clock;
+    static int64_t counter;
+    int64_t clock = get_clock();
+
+    counter++;
+    if (clock - logged_clock >= 1000000000LL) {
+        if (logged_clock > 0) { /* don't log first event */
+            trace_log_guest_storage_performance
+                (counter, (clock - logged_clock) / 1000000000LL);
+        }
+        counter = 0;
+        logged_clock = clock;
+    }
+}
+
 static int paio_submit_co(BlockDriverState *bs, int fd,
         int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
         int type)
@@ -1051,6 +1072,7 @@ static int paio_submit_co(BlockDriverState *bs, int fd,
         assert(qiov->size == acb->aio_nbytes);
     }
 
+    log_guest_storage_performance();
     trace_paio_submit_co(sector_num, nb_sectors, type);
     pool = aio_get_thread_pool(bdrv_get_aio_context(bs));
     return thread_pool_submit_co(pool, aio_worker, acb);
@@ -1076,6 +1098,7 @@ static BlockAIOCB *paio_submit(BlockDriverState *bs, int fd,
         assert(qiov->size == acb->aio_nbytes);
     }
 
+    log_guest_storage_performance();
     trace_paio_submit(acb, opaque, sector_num, nb_sectors, type);
     pool = aio_get_thread_pool(bdrv_get_aio_context(bs));
     return thread_pool_submit_aio(pool, aio_worker, acb, cb, opaque);
diff --git a/block/raw-win32.c b/block/raw-win32.c
index 7b58881..8cb2743 100644
--- a/block/raw-win32.c
+++ b/block/raw-win32.c
@@ -138,6 +138,27 @@ static int aio_worker(void *arg)
     return ret;
 }
 
+static void log_guest_storage_performance(void)
+{
+    /*
+     * Performance logging isn't specified yet.
+     * Therefore we're using existing tracing.
+     */
+    static int64_t logged_clock;
+    static int64_t counter;
+    int64_t clock = get_clock();
+
+    counter++;
+    if (clock - logged_clock >= 1000000000LL) {
+        if (logged_clock > 0) { /* don't log first event */
+            trace_log_guest_storage_performance
+                (counter, (clock - logged_clock) / 1000000000LL);
+        }
+        counter = 0;
+        logged_clock = clock;
+    }
+}
+
 static BlockAIOCB *paio_submit(BlockDriverState *bs, HANDLE hfile,
         int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
         BlockCompletionFunc *cb, void *opaque, int type)
@@ -156,6 +177,7 @@ static BlockAIOCB *paio_submit(BlockDriverState *bs, HANDLE hfile,
     acb->aio_nbytes = nb_sectors * 512;
     acb->aio_offset = sector_num * 512;
 
+    log_guest_storage_performance();
     trace_paio_submit(acb, opaque, sector_num, nb_sectors, type);
     pool = aio_get_thread_pool(bdrv_get_aio_context(bs));
     return thread_pool_submit_aio(pool, aio_worker, acb, cb, opaque);
diff --git a/include/net/queue.h b/include/net/queue.h
index fc02b33..d8ea589 100644
--- a/include/net/queue.h
+++ b/include/net/queue.h
@@ -34,6 +34,8 @@ typedef void (NetPacketSent) (NetClientState *sender, ssize_t ret);
 #define QEMU_NET_PACKET_FLAG_NONE  0
 #define QEMU_NET_PACKET_FLAG_RAW  (1<<0)
 
+void qemu_net_set_bandwidth_limit(int64_t limit);
+
 NetQueue *qemu_new_net_queue(void *opaque);
 
 void qemu_del_net_queue(NetQueue *queue);
diff --git a/net/queue.c b/net/queue.c
index f948318..2b0fef7 100644
--- a/net/queue.c
+++ b/net/queue.c
@@ -23,7 +23,9 @@
 
 #include "net/queue.h"
 #include "qemu/queue.h"
+#include "qemu/timer.h"
 #include "net/net.h"
+#include "trace.h"
 
 /* The delivery handler may only return zero if it will call
  * qemu_net_queue_flush() when it determines that it is once again able
@@ -58,6 +60,15 @@ struct NetQueue {
     unsigned delivering : 1;
 };
 
+static int64_t bandwidth_limit;     /* maximum number of bits per second */
+
+void qemu_net_set_bandwidth_limit(int64_t limit)
+{
+    bandwidth_limit = limit;
+    trace_qemu_net_set_bandwidth_limit(limit);
+}
+
+
 NetQueue *qemu_new_net_queue(void *opaque)
 {
     NetQueue *queue;
@@ -175,6 +186,48 @@ static ssize_t qemu_net_queue_deliver_iov(NetQueue *queue,
     return ret;
 }
 
+static int64_t limit_network_performance(int64_t start_clock,
+                                         int64_t bytes)
+{
+    int64_t clock = get_clock();
+    int64_t sleep_usecs = 0;
+    if (bandwidth_limit > 0) {
+        sleep_usecs = (bytes * 8 * 1000000LL) / bandwidth_limit -
+                      (clock - start_clock) / 1000LL;
+    }
+    if (sleep_usecs > 0) {
+        usleep(sleep_usecs);
+        clock = get_clock();
+    }
+
+    return clock;
+}
+
+static void log_and_limit_network_performance(size_t size)
+{
+    /*
+     * Performance logging isn't specified yet.
+     * Therefore we're using existing tracing.
+     */
+    static int64_t logged_clock;
+    static int64_t packets;
+    static int64_t bytes;
+    int64_t clock = 0;
+
+    packets++;
+    bytes = bytes + size;
+    clock = limit_network_performance(logged_clock, bytes);
+    if (clock - logged_clock >= 1000000000LL) {
+        if (logged_clock > 0) { /* don't log first event */
+            trace_log_network_performance
+                (packets, bytes*8, (clock - logged_clock) / 1000000000LL);
+        }
+        packets = 0;
+        bytes = 0;
+        logged_clock = clock;
+    }
+}
+
 ssize_t qemu_net_queue_send(NetQueue *queue,
                             NetClientState *sender,
                             unsigned flags,
@@ -184,6 +237,7 @@ ssize_t qemu_net_queue_send(NetQueue *queue,
 {
     ssize_t ret;
 
+    log_and_limit_network_performance(size) ;
     if (queue->delivering || !qemu_can_send_packet(sender)) {
         qemu_net_queue_append(queue, sender, flags, data, size, sent_cb);
         return 0;
diff --git a/qemu-options.hx b/qemu-options.hx
index 22cf3b9..35aee69 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -1916,6 +1916,19 @@ override the default configuration (@option{-net nic -net user}) which
 is activated if no @option{-net} options are provided.
 ETEXI
 
+DEF("bandwidth", HAS_ARG, QEMU_OPTION_bandwidth,
+	"-bandwidth [limit=]n\n"
+	"                set the maximum bandwidth[bits per second] to 'n' (default=0, no limit)\n",
+	    QEMU_ARCH_ALL)
+STEXI
+@item -bandwidth [limit=]@var{n}]
+@findex -bandwidth
+Limit the network bandwith (bits per second).
+If the limit is reached, Qemu will sleep.
+0, the default means no limit.
+This option is active if trace-event "log_network_performance" is active
+ETEXI
+
 STEXI
 @end table
 ETEXI
diff --git a/trace-events b/trace-events
index 6c3a400..04b2d36 100644
--- a/trace-events
+++ b/trace-events
@@ -134,6 +134,7 @@ thread_pool_cancel(void *req, void *opaque) "req %p opaque %p"
 # block/raw-posix.c
 paio_submit_co(int64_t sector_num, int nb_sectors, int type) "sector_num %"PRId64" nb_sectors %d type %d"
 paio_submit(void *acb, void *opaque, int64_t sector_num, int nb_sectors, int type) "acb %p opaque %p sector_num %"PRId64" nb_sectors %d type %d"
+log_guest_storage_performance(int64_t counter, int64_t seconds) "counter %"PRId64" seconds %"PRId64"
 
 # ioport.c
 cpu_in(unsigned int addr, unsigned int val) "addr %#x value %u"
@@ -1378,3 +1379,7 @@ i8257_unregistered_dma(int nchan, int dma_pos, int dma_len) "unregistered DMA ch
 cpu_set_state(int cpu_index, uint8_t state) "setting cpu %d state to %" PRIu8
 cpu_halt(int cpu_index) "halting cpu %d"
 cpu_unhalt(int cpu_index) "unhalting cpu %d"
+
+# net/queue.c
+qemu_net_set_bandwidth_limit(int64_t limit) "bits per second %"PRId64"
+log_network_performance(int64_t packets, int64_t bits, int64_t seconds) "packets %"PRId64" "bits %"PRId64" seconds %"PRId64"
diff --git a/vl.c b/vl.c
index 2f81384..02a91e1 100644
--- a/vl.c
+++ b/vl.c
@@ -1309,6 +1309,30 @@ static void smp_parse(QemuOpts *opts)
 
 }
 
+static QemuOptsList qemu_bandwidth_opts = {
+    .name = "bandwidth-opts",
+    .implied_opt_name = "limit",
+    .merge_lists = true,
+    .head = QTAILQ_HEAD_INITIALIZER(qemu_bandwidth_opts.head),
+    .desc = {
+        {
+            .name = "limit",
+            .type = QEMU_OPT_NUMBER,
+        },
+        { /*End of list */ }
+    },
+};
+
+static void bandwidth_parse(QemuOpts *opts)
+{
+    if (opts) {
+
+        qemu_net_set_bandwidth_limit(qemu_opt_get_number(opts, "limit", 0));
+
+    }
+
+}
+
 static void realtime_init(void)
 {
     if (enable_mlock) {
@@ -2758,6 +2782,7 @@ int main(int argc, char **argv, char **envp)
     qemu_add_opts(&qemu_machine_opts);
     qemu_add_opts(&qemu_mem_opts);
     qemu_add_opts(&qemu_smp_opts);
+    qemu_add_opts(&qemu_bandwidth_opts);
     qemu_add_opts(&qemu_boot_opts);
     qemu_add_opts(&qemu_sandbox_opts);
     qemu_add_opts(&qemu_add_fd_opts);
@@ -3517,6 +3542,12 @@ int main(int argc, char **argv, char **envp)
                     exit(1);
                 }
                 break;
+            case QEMU_OPTION_bandwidth:
+                if (!qemu_opts_parse(qemu_find_opts("bandwidth-opts"),
+                                     optarg, 1)) {
+                    exit(1);
+                }
+                break;
 	    case QEMU_OPTION_vnc:
 #ifdef CONFIG_VNC
                 display_remote++;
@@ -3862,6 +3893,8 @@ int main(int argc, char **argv, char **envp)
         exit(1);
     }
 
+    bandwidth_parse(qemu_opts_find(qemu_find_opts("bandwidth-opts"), NULL));
+
     /*
      * Get the default machine options from the machine if it is not already
      * specified either by the configuration file or by the command line.
-- 
1.9.1
Signed-off-by: Harald Schieche <rehs@gmx.de>