X-Git-Url: http://git.liburcu.org/?p=lttng-modules.git;a=blobdiff_plain;f=lib%2Fringbuffer%2Ffrontend_api.h;h=3c46a1774814d305c6cc21449b7857b9e7bbd599;hp=cc098274f4545b36a06388d582eaaaf3d6dad5f2;hb=5b4ea313ddc10d96388a20a42e118c758479a553;hpb=886d51a3d7ed5fa6b41d7f19b3e14ae6c535a44c diff --git a/lib/ringbuffer/frontend_api.h b/lib/ringbuffer/frontend_api.h index cc098274..3c46a177 100644 --- a/lib/ringbuffer/frontend_api.h +++ b/lib/ringbuffer/frontend_api.h @@ -1,36 +1,22 @@ -#ifndef _LIB_RING_BUFFER_FRONTEND_API_H -#define _LIB_RING_BUFFER_FRONTEND_API_H - -/* +/* SPDX-License-Identifier: (GPL-2.0-only OR LGPL-2.1-only) + * * lib/ringbuffer/frontend_api.h * * Ring Buffer Library Synchronization Header (buffer write API). * * Copyright (C) 2005-2012 Mathieu Desnoyers * - * This library is free software; you can redistribute it and/or - * modify it under the terms of the GNU Lesser General Public - * License as published by the Free Software Foundation; only - * version 2.1 of the License. - * - * This library is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * Lesser General Public License for more details. - * - * You should have received a copy of the GNU Lesser General Public - * License along with this library; if not, write to the Free Software - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA - * - * Author: - * Mathieu Desnoyers - * * See ring_buffer_frontend.c for more information on wait-free algorithms. * See linux/ringbuffer/frontend.h for channel allocation and read-side API. */ -#include "../../wrapper/ringbuffer/frontend.h" +#ifndef _LIB_RING_BUFFER_FRONTEND_API_H +#define _LIB_RING_BUFFER_FRONTEND_API_H + +#include +#include #include +#include /** * lib_ring_buffer_get_cpu - Precedes ring buffer reserve/commit. @@ -56,7 +42,7 @@ int lib_ring_buffer_get_cpu(const struct lib_ring_buffer_config *config) nesting = ++per_cpu(lib_ring_buffer_nesting, cpu); barrier(); - if (unlikely(nesting > 4)) { + if (unlikely(nesting > RING_BUFFER_MAX_NESTING)) { WARN_ON_ONCE(1); per_cpu(lib_ring_buffer_nesting, cpu)--; rcu_read_unlock_sched_notrace(); @@ -72,7 +58,7 @@ static inline void lib_ring_buffer_put_cpu(const struct lib_ring_buffer_config *config) { barrier(); - __get_cpu_var(lib_ring_buffer_nesting)--; + (*lttng_this_cpu_ptr(&lib_ring_buffer_nesting))--; rcu_read_unlock_sched_notrace(); } @@ -85,6 +71,7 @@ void lib_ring_buffer_put_cpu(const struct lib_ring_buffer_config *config) static inline int lib_ring_buffer_try_reserve(const struct lib_ring_buffer_config *config, struct lib_ring_buffer_ctx *ctx, + void *client_ctx, unsigned long *o_begin, unsigned long *o_end, unsigned long *o_old, size_t *before_hdr_pad) { @@ -111,7 +98,7 @@ int lib_ring_buffer_try_reserve(const struct lib_ring_buffer_config *config, return 1; ctx->slot_size = record_header_size(config, chan, *o_begin, - before_hdr_pad, ctx); + before_hdr_pad, ctx, client_ctx); ctx->slot_size += lib_ring_buffer_align(*o_begin + ctx->slot_size, ctx->largest_align) + ctx->data_size; @@ -153,28 +140,29 @@ int lib_ring_buffer_try_reserve(const struct lib_ring_buffer_config *config, static inline int lib_ring_buffer_reserve(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer_ctx *ctx) + struct lib_ring_buffer_ctx *ctx, + void *client_ctx) { struct channel *chan = ctx->chan; struct lib_ring_buffer *buf; unsigned long o_begin, o_end, o_old; size_t before_hdr_pad = 0; - if (atomic_read(&chan->record_disabled)) + if (unlikely(atomic_read(&chan->record_disabled))) return -EAGAIN; if (config->alloc == RING_BUFFER_ALLOC_PER_CPU) buf = per_cpu_ptr(chan->backend.buf, ctx->cpu); else buf = chan->backend.buf; - if (atomic_read(&buf->record_disabled)) + if (unlikely(atomic_read(&buf->record_disabled))) return -EAGAIN; ctx->buf = buf; /* * Perform retryable operations. */ - if (unlikely(lib_ring_buffer_try_reserve(config, ctx, &o_begin, + if (unlikely(lib_ring_buffer_try_reserve(config, ctx, client_ctx, &o_begin, &o_end, &o_old, &before_hdr_pad))) goto slow_path; @@ -205,7 +193,7 @@ int lib_ring_buffer_reserve(const struct lib_ring_buffer_config *config, ctx->buf_offset = o_begin + before_hdr_pad; return 0; slow_path: - return lib_ring_buffer_reserve_slow(ctx); + return lib_ring_buffer_reserve_slow(ctx, client_ctx); } /** @@ -248,6 +236,7 @@ void lib_ring_buffer_commit(const struct lib_ring_buffer_config *config, unsigned long offset_end = ctx->buf_offset; unsigned long endidx = subbuf_index(offset_end - 1, chan); unsigned long commit_count; + struct commit_counters_hot *cc_hot = &buf->commit_hot[endidx]; /* * Must count record before incrementing the commit count. @@ -268,7 +257,7 @@ void lib_ring_buffer_commit(const struct lib_ring_buffer_config *config, } else smp_wmb(); - v_add(config, ctx->slot_size, &buf->commit_hot[endidx].cc); + v_add(config, ctx->slot_size, &cc_hot->cc); /* * commit count read can race with concurrent OOO commit count updates. @@ -288,17 +277,16 @@ void lib_ring_buffer_commit(const struct lib_ring_buffer_config *config, * count reaches back the reserve offset for a specific sub-buffer, * which is completely independent of the order. */ - commit_count = v_read(config, &buf->commit_hot[endidx].cc); + commit_count = v_read(config, &cc_hot->cc); lib_ring_buffer_check_deliver(config, buf, chan, offset_end - 1, - commit_count, endidx); + commit_count, endidx, ctx->tsc); /* * Update used size at each commit. It's needed only for extracting * ring_buffer buffers from vmcore, after crash. */ - lib_ring_buffer_write_commit_counter(config, buf, chan, endidx, - ctx->buf_offset, commit_count, - ctx->slot_size); + lib_ring_buffer_write_commit_counter(config, buf, chan, + offset_end, commit_count, cc_hot); } /**