From patchwork Mon Jun 4 09:57:28 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Isaku Yamahata X-Patchwork-Id: 162762 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id CAA81B6FD7 for ; Mon, 4 Jun 2012 21:45:20 +1000 (EST) Received: from localhost ([::1]:41718 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SbU5H-00034o-KC for incoming@patchwork.ozlabs.org; Mon, 04 Jun 2012 06:00:23 -0400 Received: from eggs.gnu.org ([208.118.235.92]:51039) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SbU32-0008TL-Jr for qemu-devel@nongnu.org; Mon, 04 Jun 2012 05:58:19 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SbU2q-0004cw-TD for qemu-devel@nongnu.org; Mon, 04 Jun 2012 05:58:04 -0400 Received: from mail.valinux.co.jp ([210.128.90.3]:46496) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SbU2q-0004ae-DS for qemu-devel@nongnu.org; Mon, 04 Jun 2012 05:57:52 -0400 Received: from ps.local.valinux.co.jp (vagw.valinux.co.jp [210.128.90.14]) by mail.valinux.co.jp (Postfix) with SMTP id 1F64548990; Mon, 4 Jun 2012 18:57:46 +0900 (JST) Received: (nullmailer pid 5152 invoked by uid 1000); Mon, 04 Jun 2012 09:57:45 -0000 From: Isaku Yamahata To: qemu-devel@nongnu.org, kvm@vger.kernel.org Date: Mon, 4 Jun 2012 18:57:28 +0900 Message-Id: <8e4441af2592acd87d24ec8935b298bb18e9a2e4.1338802192.git.yamahata@valinux.co.jp> X-Mailer: git-send-email 1.7.1.1 In-Reply-To: References: In-Reply-To: References: X-Virus-Scanned: clamav-milter 0.95.2 at va-mail.local.valinux.co.jp X-Virus-Status: Clean X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 3) X-Received-From: 210.128.90.3 Cc: benoit.hudzia@gmail.com, aarcange@redhat.com, aliguori@us.ibm.com, quintela@redhat.com, stefanha@gmail.com, t.hirofuchi@aist.go.jp, dlaor@redhat.com, satoshi.itoh@aist.go.jp, mdroth@linux.vnet.ibm.com, yoshikawa.takuya@oss.ntt.co.jp, owasserm@redhat.com, avi@redhat.com, pbonzini@redhat.com Subject: [Qemu-devel] [PATCH v2 26/41] buffered_file: factor out buffer management logic X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org This patch factors out buffer management logic. Signed-off-by: Isaku Yamahata --- buffered_file.c | 141 +++++++++++++++++++++++++++++++++--------------------- buffered_file.h | 8 +++ 2 files changed, 94 insertions(+), 55 deletions(-) diff --git a/buffered_file.c b/buffered_file.c index a38caec..22dd4c9 100644 --- a/buffered_file.c +++ b/buffered_file.c @@ -20,24 +20,6 @@ #include "buffered_file.h" //#define DEBUG_BUFFERED_FILE - -typedef struct QEMUFileBuffered -{ - BufferedPutFunc *put_buffer; - BufferedPutReadyFunc *put_ready; - BufferedWaitForUnfreezeFunc *wait_for_unfreeze; - BufferedCloseFunc *close; - void *opaque; - QEMUFile *file; - int freeze_output; - size_t bytes_xfer; - size_t xfer_limit; - uint8_t *buffer; - size_t buffer_size; - size_t buffer_capacity; - QEMUTimer *timer; -} QEMUFileBuffered; - #ifdef DEBUG_BUFFERED_FILE #define DPRINTF(fmt, ...) \ do { printf("buffered-file: " fmt, ## __VA_ARGS__); } while (0) @@ -46,57 +28,71 @@ typedef struct QEMUFileBuffered do { } while (0) #endif -static void buffered_append(QEMUFileBuffered *s, - const uint8_t *buf, size_t size) -{ - if (size > (s->buffer_capacity - s->buffer_size)) { - void *tmp; - - DPRINTF("increasing buffer capacity from %zu by %zu\n", - s->buffer_capacity, size + 1024); - s->buffer_capacity += size + 1024; +/*************************************************************************** + * buffer management + */ - tmp = g_realloc(s->buffer, s->buffer_capacity); - if (tmp == NULL) { - fprintf(stderr, "qemu file buffer expansion failed\n"); - exit(1); - } +static void buffer_destroy(QEMUBuffer *s) +{ + g_free(s->buffer); +} - s->buffer = tmp; +static void buffer_consume(QEMUBuffer *s, size_t offset) +{ + if (offset > 0) { + assert(s->buffer_size >= offset); + memmove(s->buffer, s->buffer + offset, s->buffer_size - offset); + s->buffer_size -= offset; } +} +static void buffer_append(QEMUBuffer *s, const uint8_t *buf, size_t size) +{ +#define BUF_SIZE_INC (32 * 1024) /* = IO_BUF_SIZE */ + int inc = size - (s->buffer_capacity - s->buffer_size); + if (inc > 0) { + s->buffer_capacity += DIV_ROUND_UP(inc, BUF_SIZE_INC) * BUF_SIZE_INC; + s->buffer = g_realloc(s->buffer, s->buffer_capacity); + } memcpy(s->buffer + s->buffer_size, buf, size); s->buffer_size += size; } -static void buffered_flush(QEMUFileBuffered *s) +typedef ssize_t (BufferPutBuf)(void *opaque, const void *data, size_t size); + +static void buffer_flush(QEMUBuffer *buf, QEMUFile *file, + void *opaque, BufferPutBuf *put_buf) { size_t offset = 0; int error; - error = qemu_file_get_error(s->file); + error = qemu_file_get_error(file); if (error != 0) { DPRINTF("flush when error, bailing: %s\n", strerror(-error)); return; } - DPRINTF("flushing %zu byte(s) of data\n", s->buffer_size); + DPRINTF("flushing %zu byte(s) of data\n", buf->buffer_size); - while (offset < s->buffer_size) { + while (offset < buf->buffer_size) { ssize_t ret; - ret = s->put_buffer(s->opaque, s->buffer + offset, - s->buffer_size - offset); - if (ret == -EAGAIN) { + ret = put_buf(opaque, buf->buffer + offset, buf->buffer_size - offset); + if (ret == -EINTR) { + continue; + } else if (ret == -EAGAIN) { DPRINTF("backend not ready, freezing\n"); - s->freeze_output = 1; + buf->freeze_output = true; break; } - if (ret <= 0) { + if (ret < 0) { DPRINTF("error flushing data, %zd\n", ret); - qemu_file_set_error(s->file, ret); + qemu_file_set_error(file, ret); + break; + } else if (ret == 0) { + DPRINTF("ret == 0\n"); break; } else { DPRINTF("flushed %zd byte(s)\n", ret); @@ -104,9 +100,44 @@ static void buffered_flush(QEMUFileBuffered *s) } } - DPRINTF("flushed %zu of %zu byte(s)\n", offset, s->buffer_size); - memmove(s->buffer, s->buffer + offset, s->buffer_size - offset); - s->buffer_size -= offset; + DPRINTF("flushed %zu of %zu byte(s)\n", offset, buf->buffer_size); + buffer_consume(buf, offset); +} + + +/*************************************************************************** + * Buffered File + */ + +typedef struct QEMUFileBuffered +{ + BufferedPutFunc *put_buffer; + BufferedPutReadyFunc *put_ready; + BufferedWaitForUnfreezeFunc *wait_for_unfreeze; + BufferedCloseFunc *close; + void *opaque; + QEMUFile *file; + size_t bytes_xfer; + size_t xfer_limit; + QEMUTimer *timer; + QEMUBuffer buf; +} QEMUFileBuffered; + +static ssize_t buffered_flush_putbuf(void *opaque, + const void *data, size_t size) +{ + QEMUFileBuffered *s = opaque; + ssize_t ret = s->put_buffer(s->opaque, data, size); + if (ret == 0) { + DPRINTF("error flushing data, %zd\n", ret); + qemu_file_set_error(s->file, ret); + } + return ret; +} + +static void buffered_flush(QEMUFileBuffered *s) +{ + buffer_flush(&s->buf, s->file, s, buffered_flush_putbuf); } static int buffered_put_buffer(void *opaque, const uint8_t *buf, int64_t pos, int size) @@ -124,11 +155,11 @@ static int buffered_put_buffer(void *opaque, const uint8_t *buf, int64_t pos, in } DPRINTF("unfreezing output\n"); - s->freeze_output = 0; + s->buf.freeze_output = false; buffered_flush(s); - while (!s->freeze_output && offset < size) { + while (!s->buf.freeze_output && offset < size) { if (s->bytes_xfer > s->xfer_limit) { DPRINTF("transfer limit exceeded when putting\n"); break; @@ -137,7 +168,7 @@ static int buffered_put_buffer(void *opaque, const uint8_t *buf, int64_t pos, in ret = s->put_buffer(s->opaque, buf + offset, size - offset); if (ret == -EAGAIN) { DPRINTF("backend not ready, freezing\n"); - s->freeze_output = 1; + s->buf.freeze_output = true; break; } @@ -155,7 +186,7 @@ static int buffered_put_buffer(void *opaque, const uint8_t *buf, int64_t pos, in if (offset >= 0) { DPRINTF("buffering %d bytes\n", size - offset); - buffered_append(s, buf + offset, size - offset); + buffer_append(&s->buf, buf + offset, size - offset); offset = size; } @@ -172,9 +203,9 @@ static int buffered_put_buffer(void *opaque, const uint8_t *buf, int64_t pos, in static void buffered_drain(QEMUFileBuffered *s) { - while (!qemu_file_get_error(s->file) && s->buffer_size) { + while (!qemu_file_get_error(s->file) && s->buf.buffer_size) { buffered_flush(s); - if (s->freeze_output) + if (s->buf.freeze_output) s->wait_for_unfreeze(s->opaque); } } @@ -192,7 +223,7 @@ static int buffered_close(void *opaque) qemu_del_timer(s->timer); qemu_free_timer(s->timer); - g_free(s->buffer); + buffer_destroy(&s->buf); g_free(s); return ret; @@ -213,7 +244,7 @@ static int buffered_rate_limit(void *opaque) if (ret) { return ret; } - if (s->freeze_output) + if (s->buf.freeze_output) return 1; if (s->bytes_xfer > s->xfer_limit) @@ -256,7 +287,7 @@ static void buffered_rate_tick(void *opaque) qemu_mod_timer(s->timer, qemu_get_clock_ms(rt_clock) + 100); - if (s->freeze_output) + if (s->buf.freeze_output) return; s->bytes_xfer = 0; diff --git a/buffered_file.h b/buffered_file.h index cd8e1e8..d3ef546 100644 --- a/buffered_file.h +++ b/buffered_file.h @@ -16,6 +16,14 @@ #include "hw/hw.h" +struct QEMUBuffer { + uint8_t *buffer; + size_t buffer_size; + size_t buffer_capacity; + bool freeze_output; +}; +typedef struct QEMUBuffer QEMUBuffer; + typedef ssize_t (BufferedPutFunc)(void *opaque, const void *data, size_t size); typedef void (BufferedPutReadyFunc)(void *opaque); typedef void (BufferedWaitForUnfreezeFunc)(void *opaque);