stream: move rate limiting to a separate header file
Make the code reusable. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
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			@ -13,6 +13,7 @@
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#include "trace.h"
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#include "block_int.h"
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#include "qemu/ratelimit.h"
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enum {
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    /*
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			@ -25,34 +26,6 @@ enum {
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#define SLICE_TIME 100000000ULL /* ns */
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typedef struct {
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    int64_t next_slice_time;
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    uint64_t slice_quota;
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    uint64_t dispatched;
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} RateLimit;
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static int64_t ratelimit_calculate_delay(RateLimit *limit, uint64_t n)
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{
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    int64_t now = qemu_get_clock_ns(rt_clock);
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    if (limit->next_slice_time < now) {
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        limit->next_slice_time = now + SLICE_TIME;
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        limit->dispatched = 0;
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    }
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    if (limit->dispatched == 0 || limit->dispatched + n <= limit->slice_quota) {
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        limit->dispatched += n;
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        return 0;
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    } else {
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        limit->dispatched = n;
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        return limit->next_slice_time - now;
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    }
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}
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static void ratelimit_set_speed(RateLimit *limit, uint64_t speed)
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{
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    limit->slice_quota = speed / (1000000000ULL / SLICE_TIME);
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}
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typedef struct StreamBlockJob {
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    BlockJob common;
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    RateLimit limit;
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			@ -198,7 +171,7 @@ static void stream_set_speed(BlockJob *job, int64_t speed, Error **errp)
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        error_set(errp, QERR_INVALID_PARAMETER, "speed");
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        return;
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    }
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    ratelimit_set_speed(&s->limit, speed / BDRV_SECTOR_SIZE);
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    ratelimit_set_speed(&s->limit, speed / BDRV_SECTOR_SIZE, SLICE_TIME);
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}
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static BlockJobType stream_job_type = {
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			@ -0,0 +1,48 @@
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/*
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 * Ratelimiting calculations
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 *
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 * Copyright IBM, Corp. 2011
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 *
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 * Authors:
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 *  Stefan Hajnoczi   <stefanha@linux.vnet.ibm.com>
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 *
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 * This work is licensed under the terms of the GNU LGPL, version 2 or later.
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 * See the COPYING.LIB file in the top-level directory.
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 *
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 */
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#ifndef QEMU_RATELIMIT_H
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#define QEMU_RATELIMIT_H 1
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typedef struct {
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    int64_t next_slice_time;
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    uint64_t slice_quota;
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    uint64_t slice_ns;
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    uint64_t dispatched;
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} RateLimit;
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static inline int64_t ratelimit_calculate_delay(RateLimit *limit, uint64_t n)
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{
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    int64_t now = qemu_get_clock_ns(rt_clock);
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    if (limit->next_slice_time < now) {
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        limit->next_slice_time = now + limit->slice_ns;
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        limit->dispatched = 0;
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    }
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    if (limit->dispatched == 0 || limit->dispatched + n <= limit->slice_quota) {
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        limit->dispatched += n;
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        return 0;
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    } else {
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        limit->dispatched = n;
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        return limit->next_slice_time - now;
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    }
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}
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static inline void ratelimit_set_speed(RateLimit *limit, uint64_t speed,
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                                       uint64_t slice_ns)
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{
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    limit->slice_ns = slice_ns;
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    limit->slice_quota = ((double)speed * 1000000000ULL) / slice_ns;
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}
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#endif
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