0cdfb3b207
ids_inflight is used to track the inflight IOs. But the use of atomic_t
variable can cause performance drops and can also become a performance
bottleneck.
This commit replaces the use of atomic_t with a percpu_ref structure. The
advantage it offers is, it doesn't check if the reference has fallen to 0,
until the user explicitly signals it to; and that is done by the
percpu_ref_kill() function call. After that, the percpu_ref structure
behaves like an atomic_t and for every put call, checks whether the
reference has fallen to 0 or not.
rtrs_srv_stats_rdma_to_str shows the count of ids_inflight as 0
for user-mode tools not to be confused.
Fixes: 9cb837480424e ("RDMA/rtrs: server: main functionality")
Link: https://lore.kernel.org/r/20210528113018.52290-14-jinpu.wang@ionos.com
Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
37 lines
1023 B
C
37 lines
1023 B
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* RDMA Transport Layer
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*
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* Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
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* Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
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* Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
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*/
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#undef pr_fmt
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#define pr_fmt(fmt) KBUILD_MODNAME " L" __stringify(__LINE__) ": " fmt
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#include "rtrs-srv.h"
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int rtrs_srv_reset_rdma_stats(struct rtrs_srv_stats *stats, bool enable)
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{
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if (enable) {
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struct rtrs_srv_stats_rdma_stats *r = &stats->rdma_stats;
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memset(r, 0, sizeof(*r));
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return 0;
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}
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return -EINVAL;
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}
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ssize_t rtrs_srv_stats_rdma_to_str(struct rtrs_srv_stats *stats,
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char *page, size_t len)
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{
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struct rtrs_srv_stats_rdma_stats *r = &stats->rdma_stats;
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return scnprintf(page, len, "%lld %lld %lld %lldn %u\n",
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(s64)atomic64_read(&r->dir[READ].cnt),
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(s64)atomic64_read(&r->dir[READ].size_total),
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(s64)atomic64_read(&r->dir[WRITE].cnt),
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(s64)atomic64_read(&r->dir[WRITE].size_total), 0);
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}
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