diff options
Diffstat (limited to 'sys/dev/hwt/hwt_context.c')
| -rw-r--r-- | sys/dev/hwt/hwt_context.c | 201 |
1 files changed, 201 insertions, 0 deletions
diff --git a/sys/dev/hwt/hwt_context.c b/sys/dev/hwt/hwt_context.c new file mode 100644 index 000000000000..9af76cffc928 --- /dev/null +++ b/sys/dev/hwt/hwt_context.c @@ -0,0 +1,201 @@ +/*- + * SPDX-License-Identifier: BSD-2-Clause + * + * Copyright (c) 2023-2025 Ruslan Bukin <br@bsdpad.com> + * + * This work was supported by Innovate UK project 105694, "Digital Security + * by Design (DSbD) Technology Platform Prototype". + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <sys/param.h> +#include <sys/bitstring.h> +#include <sys/conf.h> +#include <sys/proc.h> +#include <sys/kernel.h> +#include <sys/malloc.h> +#include <sys/mman.h> +#include <sys/mutex.h> +#include <sys/refcount.h> +#include <sys/rwlock.h> +#include <sys/hwt.h> + +#include <dev/hwt/hwt_hook.h> +#include <dev/hwt/hwt_context.h> +#include <dev/hwt/hwt_config.h> +#include <dev/hwt/hwt_thread.h> +#include <dev/hwt/hwt_owner.h> +#include <dev/hwt/hwt_vm.h> +#include <dev/hwt/hwt_cpu.h> + +#define HWT_DEBUG +#undef HWT_DEBUG + +#ifdef HWT_DEBUG +#define dprintf(fmt, ...) printf(fmt, ##__VA_ARGS__) +#else +#define dprintf(fmt, ...) +#endif + +static MALLOC_DEFINE(M_HWT_CTX, "hwt_ctx", "Hardware Trace"); + +static bitstr_t *ident_set; +static int ident_set_size; +static struct mtx ident_set_mutex; + +static int +hwt_ctx_ident_alloc(int *new_ident) +{ + + mtx_lock(&ident_set_mutex); + bit_ffc(ident_set, ident_set_size, new_ident); + if (*new_ident == -1) { + mtx_unlock(&ident_set_mutex); + return (ENOMEM); + } + bit_set(ident_set, *new_ident); + mtx_unlock(&ident_set_mutex); + + return (0); +} + +static void +hwt_ctx_ident_free(int ident) +{ + + mtx_lock(&ident_set_mutex); + bit_clear(ident_set, ident); + mtx_unlock(&ident_set_mutex); +} + +int +hwt_ctx_alloc(struct hwt_context **ctx0) +{ + struct hwt_context *ctx; + int error; + + ctx = malloc(sizeof(struct hwt_context), M_HWT_CTX, M_WAITOK | M_ZERO); + + TAILQ_INIT(&ctx->records); + TAILQ_INIT(&ctx->threads); + TAILQ_INIT(&ctx->cpus); + mtx_init(&ctx->mtx, "ctx", NULL, MTX_SPIN); + mtx_init(&ctx->rec_mtx, "ctx_rec", NULL, MTX_DEF); + refcount_init(&ctx->refcnt, 0); + + error = hwt_ctx_ident_alloc(&ctx->ident); + if (error) { + printf("could not allocate ident bit str\n"); + return (error); + } + + *ctx0 = ctx; + + return (0); +} + +static void +hwt_ctx_free_cpus(struct hwt_context *ctx) +{ + struct hwt_cpu *cpu; + + do { + HWT_CTX_LOCK(ctx); + cpu = TAILQ_FIRST(&ctx->cpus); + if (cpu) + TAILQ_REMOVE(&ctx->cpus, cpu, next); + HWT_CTX_UNLOCK(ctx); + + if (cpu == NULL) + break; + + /* TODO: move vm_free() to cpu_free()? */ + hwt_vm_free(cpu->vm); + hwt_cpu_free(cpu); + } while (1); +} + +static void +hwt_ctx_free_threads(struct hwt_context *ctx) +{ + struct hwt_thread *thr; + + dprintf("%s: remove threads\n", __func__); + + do { + HWT_CTX_LOCK(ctx); + thr = TAILQ_FIRST(&ctx->threads); + if (thr) + TAILQ_REMOVE(&ctx->threads, thr, next); + HWT_CTX_UNLOCK(ctx); + + if (thr == NULL) + break; + + HWT_THR_LOCK(thr); + /* TODO: check if thr is sleeping before waking it up. */ + wakeup(thr); + HWT_THR_UNLOCK(thr); + + if (refcount_release(&thr->refcnt)) + hwt_thread_free(thr); + } while (1); +} + +void +hwt_ctx_free(struct hwt_context *ctx) +{ + + if (ctx->mode == HWT_MODE_CPU) + hwt_ctx_free_cpus(ctx); + else + hwt_ctx_free_threads(ctx); + + hwt_config_free(ctx); + hwt_ctx_ident_free(ctx->ident); + free(ctx, M_HWT_CTX); +} + +void +hwt_ctx_put(struct hwt_context *ctx) +{ + + refcount_release(&ctx->refcnt); +} + +void +hwt_ctx_load(void) +{ + + ident_set_size = (1 << 8); + ident_set = bit_alloc(ident_set_size, M_HWT_CTX, M_WAITOK); + mtx_init(&ident_set_mutex, "ident set", NULL, MTX_DEF); +} + +void +hwt_ctx_unload(void) +{ + + mtx_destroy(&ident_set_mutex); + free(ident_set, M_HWT_CTX); +} |