From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:53123) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TF5JG-0005iL-1H for qemu-devel@nongnu.org; Fri, 21 Sep 2012 11:38:36 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TF5J6-0000jx-0e for qemu-devel@nongnu.org; Fri, 21 Sep 2012 11:38:29 -0400 Received: from mail-pb0-f45.google.com ([209.85.160.45]:48048) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TF5J5-0000jr-Nq for qemu-devel@nongnu.org; Fri, 21 Sep 2012 11:38:19 -0400 Received: by pbbrp12 with SMTP id rp12so7945954pbb.4 for ; Fri, 21 Sep 2012 08:38:19 -0700 (PDT) Sender: Paolo Bonzini Message-ID: <505C87F6.8020807@redhat.com> Date: Fri, 21 Sep 2012 17:29:58 +0200 From: Paolo Bonzini MIME-Version: 1.0 References: <1348236500-2565-1-git-send-email-quintela@redhat.com> <1348236500-2565-5-git-send-email-quintela@redhat.com> In-Reply-To: <1348236500-2565-5-git-send-email-quintela@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 04/14] buffered_file: Move from using a timer to use a thread List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Juan Quintela Cc: qemu-devel@nongnu.org Il 21/09/2012 16:08, Juan Quintela ha scritto: > We still protect everything except the wait with the iothread lock. > But we moved from a timer to a thread. Steps one by one. > > We also need to detect when we have finished with a variable "complete". > > Signed-off-by: Juan Quintela > --- > buffered_file.c | 58 +++++++++++++++++++++++++++++++++++---------------------- > 1 file changed, 36 insertions(+), 22 deletions(-) > > diff --git a/buffered_file.c b/buffered_file.c > index 318d0f0..61985a9 100644 > --- a/buffered_file.c > +++ b/buffered_file.c > @@ -18,6 +18,7 @@ > #include "qemu-timer.h" > #include "qemu-char.h" > #include "buffered_file.h" > +#include "qemu-thread.h" > > //#define DEBUG_BUFFERED_FILE > > @@ -31,7 +32,8 @@ typedef struct QEMUFileBuffered > uint8_t *buffer; > size_t buffer_size; > size_t buffer_capacity; > - QEMUTimer *timer; > + QemuThread thread; > + bool complete; > } QEMUFileBuffered; > > #ifdef DEBUG_BUFFERED_FILE > @@ -159,11 +161,8 @@ static int buffered_close(void *opaque) > if (ret >= 0) { > ret = ret2; > } > - qemu_del_timer(s->timer); > - qemu_free_timer(s->timer); > - g_free(s->buffer); > - g_free(s); > - > + ret = migrate_fd_close(s->migration_state); > + s->complete = true; > return ret; > } > > @@ -214,23 +213,38 @@ static int64_t buffered_get_rate_limit(void *opaque) > return s->xfer_limit; > } > > -static void buffered_rate_tick(void *opaque) > +/* 10ms xfer_limit is the limit that we should write each 10ms */ > +#define BUFFER_DELAY 100 > + > +static void *buffered_file_thread(void *opaque) > { > QEMUFileBuffered *s = opaque; > + int64_t expire_time = qemu_get_clock_ms(rt_clock) + BUFFER_DELAY; > > - if (qemu_file_get_error(s->file)) { > - buffered_close(s); > - return; > - } > - > - qemu_mod_timer(s->timer, qemu_get_clock_ms(rt_clock) + 100); > - > - if (s->freeze_output) > - return; > - > - s->bytes_xfer = 0; > + while (true) { > + int64_t current_time = qemu_get_clock_ms(rt_clock); > > - buffered_put_buffer(s, NULL, 0, 0); > + if (s->complete) { > + break; > + } > + if (s->freeze_output) { > + continue; > + } > + if (current_time >= expire_time) { > + s->bytes_xfer = 0; > + expire_time = current_time + BUFFER_DELAY; > + } > + if (s->bytes_xfer >= s->xfer_limit) { > + /* usleep expects microseconds */ > + usleep((expire_time - current_time)*1000); usleep is broken under IIRC Solaris (it uses signals and conflicts with qemu-timer.c). Please use g_usleep instead. Bonus points for converting other users (hw/xenfb.c, qemu-ga.c, tests/test-iov.c). > + } > + qemu_mutex_lock_iothread(); > + buffered_put_buffer(s, NULL, 0, 0); > + qemu_mutex_unlock_iothread(); > + } > + g_free(s->buffer); > + g_free(s); I think freeing "s" here is incorrect. Instead, you should "join" the thread after setting s->complete = true, and move the g_free(s) to buffered_close. > + return NULL; > } > > QEMUFile *qemu_fopen_ops_buffered(MigrationState *migration_state) > @@ -241,15 +255,15 @@ QEMUFile *qemu_fopen_ops_buffered(MigrationState *migration_state) > > s->migration_state = migration_state; > s->xfer_limit = migration_state->bandwidth_limit / 10; > + s->complete = false; > > s->file = qemu_fopen_ops(s, buffered_put_buffer, NULL, > buffered_close, buffered_rate_limit, > buffered_set_rate_limit, > buffered_get_rate_limit); > > - s->timer = qemu_new_timer_ms(rt_clock, buffered_rate_tick, s); > - > - qemu_mod_timer(s->timer, qemu_get_clock_ms(rt_clock) + 100); > + qemu_thread_create(&s->thread, buffered_file_thread, s, > + QEMU_THREAD_DETACHED); So this needs to become QEMU_THREAD_JOINABLE. > > return s->file; > } > Paolo