+++ /dev/null
-/*
- * SPDX-License-Identifier: LGPL-2.1-only
- *
- * Copyright (C) 2005-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- */
-
-#define _LGPL_SOURCE
-#include "shm.h"
-#include <unistd.h>
-#include <fcntl.h>
-#include <sys/mman.h>
-#include <sys/types.h>
-#include <sys/stat.h> /* For mode constants */
-#include <fcntl.h> /* For O_* constants */
-#include <assert.h>
-#include <stdio.h>
-#include <signal.h>
-#include <dirent.h>
-#include <limits.h>
-#include <stdbool.h>
-#include <stdint.h>
-
-#ifdef HAVE_LIBNUMA
-#include <numa.h>
-#include <numaif.h>
-#endif
-
-#include <lttng/ust-utils.h>
-
-#include <ust-helper.h>
-#include <ust-fd.h>
-#include "mmap.h"
-
-/*
- * Ensure we have the required amount of space available by writing 0
- * into the entire buffer. Not doing so can trigger SIGBUS when going
- * beyond the available shm space.
- */
-static
-int zero_file(int fd, size_t len)
-{
- ssize_t retlen;
- size_t written = 0;
- char *zeropage;
- long pagelen;
- int ret;
-
- pagelen = sysconf(_SC_PAGESIZE);
- if (pagelen < 0)
- return (int) pagelen;
- zeropage = calloc(pagelen, 1);
- if (!zeropage)
- return -ENOMEM;
-
- while (len > written) {
- do {
- retlen = write(fd, zeropage,
- min_t(size_t, pagelen, len - written));
- } while (retlen == -1UL && errno == EINTR);
- if (retlen < 0) {
- ret = (int) retlen;
- goto error;
- }
- written += retlen;
- }
- ret = 0;
-error:
- free(zeropage);
- return ret;
-}
-
-struct shm_object_table *shm_object_table_create(size_t max_nb_obj)
-{
- struct shm_object_table *table;
-
- table = zmalloc(sizeof(struct shm_object_table) +
- max_nb_obj * sizeof(table->objects[0]));
- if (!table)
- return NULL;
- table->size = max_nb_obj;
- return table;
-}
-
-static
-struct shm_object *_shm_object_table_alloc_shm(struct shm_object_table *table,
- size_t memory_map_size,
- int stream_fd)
-{
- int shmfd, waitfd[2], ret, i;
- struct shm_object *obj;
- char *memory_map;
-
- if (stream_fd < 0)
- return NULL;
- if (table->allocated_len >= table->size)
- return NULL;
- obj = &table->objects[table->allocated_len];
-
- /* wait_fd: create pipe */
- ret = pipe(waitfd);
- if (ret < 0) {
- PERROR("pipe");
- goto error_pipe;
- }
- for (i = 0; i < 2; i++) {
- ret = fcntl(waitfd[i], F_SETFD, FD_CLOEXEC);
- if (ret < 0) {
- PERROR("fcntl");
- goto error_fcntl;
- }
- }
- /* The write end of the pipe needs to be non-blocking */
- ret = fcntl(waitfd[1], F_SETFL, O_NONBLOCK);
- if (ret < 0) {
- PERROR("fcntl");
- goto error_fcntl;
- }
- memcpy(obj->wait_fd, waitfd, sizeof(waitfd));
-
- /*
- * Set POSIX shared memory object size
- *
- * First, use ftruncate() to set its size, some implementations won't
- * allow writes past the size set by ftruncate.
- * Then, use write() to fill it with zeros, this allows us to fully
- * allocate it and detect a shortage of shm space without dealing with
- * a SIGBUS.
- */
-
- shmfd = stream_fd;
- ret = ftruncate(shmfd, memory_map_size);
- if (ret) {
- PERROR("ftruncate");
- goto error_ftruncate;
- }
- ret = zero_file(shmfd, memory_map_size);
- if (ret) {
- PERROR("zero_file");
- goto error_zero_file;
- }
-
- /*
- * Also ensure the file metadata is synced with the storage by using
- * fsync(2). Some platforms don't allow fsync on POSIX shm fds, ignore
- * EINVAL accordingly.
- */
- ret = fsync(shmfd);
- if (ret && errno != EINVAL) {
- PERROR("fsync");
- goto error_fsync;
- }
- obj->shm_fd_ownership = 0;
- obj->shm_fd = shmfd;
-
- /* memory_map: mmap */
- memory_map = mmap(NULL, memory_map_size, PROT_READ | PROT_WRITE,
- MAP_SHARED | LTTNG_MAP_POPULATE, shmfd, 0);
- if (memory_map == MAP_FAILED) {
- PERROR("mmap");
- goto error_mmap;
- }
- obj->type = SHM_OBJECT_SHM;
- obj->memory_map = memory_map;
- obj->memory_map_size = memory_map_size;
- obj->allocated_len = 0;
- obj->index = table->allocated_len++;
-
- return obj;
-
-error_mmap:
-error_fsync:
-error_ftruncate:
-error_zero_file:
-error_fcntl:
- for (i = 0; i < 2; i++) {
- ret = close(waitfd[i]);
- if (ret) {
- PERROR("close");
- assert(0);
- }
- }
-error_pipe:
- return NULL;
-}
-
-static
-struct shm_object *_shm_object_table_alloc_mem(struct shm_object_table *table,
- size_t memory_map_size)
-{
- struct shm_object *obj;
- void *memory_map;
- int waitfd[2], i, ret;
-
- if (table->allocated_len >= table->size)
- return NULL;
- obj = &table->objects[table->allocated_len];
-
- memory_map = zmalloc(memory_map_size);
- if (!memory_map)
- goto alloc_error;
-
- /* wait_fd: create pipe */
- ret = pipe(waitfd);
- if (ret < 0) {
- PERROR("pipe");
- goto error_pipe;
- }
- for (i = 0; i < 2; i++) {
- ret = fcntl(waitfd[i], F_SETFD, FD_CLOEXEC);
- if (ret < 0) {
- PERROR("fcntl");
- goto error_fcntl;
- }
- }
- /* The write end of the pipe needs to be non-blocking */
- ret = fcntl(waitfd[1], F_SETFL, O_NONBLOCK);
- if (ret < 0) {
- PERROR("fcntl");
- goto error_fcntl;
- }
- memcpy(obj->wait_fd, waitfd, sizeof(waitfd));
-
- /* no shm_fd */
- obj->shm_fd = -1;
- obj->shm_fd_ownership = 0;
-
- obj->type = SHM_OBJECT_MEM;
- obj->memory_map = memory_map;
- obj->memory_map_size = memory_map_size;
- obj->allocated_len = 0;
- obj->index = table->allocated_len++;
-
- return obj;
-
-error_fcntl:
- for (i = 0; i < 2; i++) {
- ret = close(waitfd[i]);
- if (ret) {
- PERROR("close");
- assert(0);
- }
- }
-error_pipe:
- free(memory_map);
-alloc_error:
- return NULL;
-}
-
-/*
- * libnuma prints errors on the console even for numa_available().
- * Work-around this limitation by using get_mempolicy() directly to
- * check whether the kernel supports mempolicy.
- */
-#ifdef HAVE_LIBNUMA
-static bool lttng_is_numa_available(void)
-{
- int ret;
-
- ret = get_mempolicy(NULL, NULL, 0, NULL, 0);
- if (ret && errno == ENOSYS) {
- return false;
- }
- return numa_available() > 0;
-}
-#endif
-
-struct shm_object *shm_object_table_alloc(struct shm_object_table *table,
- size_t memory_map_size,
- enum shm_object_type type,
- int stream_fd,
- int cpu)
-{
- struct shm_object *shm_object;
-#ifdef HAVE_LIBNUMA
- int oldnode = 0, node;
- bool numa_avail;
-
- numa_avail = lttng_is_numa_available();
- if (numa_avail) {
- oldnode = numa_preferred();
- if (cpu >= 0) {
- node = numa_node_of_cpu(cpu);
- if (node >= 0)
- numa_set_preferred(node);
- }
- if (cpu < 0 || node < 0)
- numa_set_localalloc();
- }
-#endif /* HAVE_LIBNUMA */
- switch (type) {
- case SHM_OBJECT_SHM:
- shm_object = _shm_object_table_alloc_shm(table, memory_map_size,
- stream_fd);
- break;
- case SHM_OBJECT_MEM:
- shm_object = _shm_object_table_alloc_mem(table, memory_map_size);
- break;
- default:
- assert(0);
- }
-#ifdef HAVE_LIBNUMA
- if (numa_avail)
- numa_set_preferred(oldnode);
-#endif /* HAVE_LIBNUMA */
- return shm_object;
-}
-
-struct shm_object *shm_object_table_append_shm(struct shm_object_table *table,
- int shm_fd, int wakeup_fd, uint32_t stream_nr,
- size_t memory_map_size)
-{
- struct shm_object *obj;
- char *memory_map;
- int ret;
-
- if (table->allocated_len >= table->size)
- return NULL;
- /* streams _must_ be received in sequential order, else fail. */
- if (stream_nr + 1 != table->allocated_len)
- return NULL;
-
- obj = &table->objects[table->allocated_len];
-
- /* wait_fd: set write end of the pipe. */
- obj->wait_fd[0] = -1; /* read end is unset */
- obj->wait_fd[1] = wakeup_fd;
- obj->shm_fd = shm_fd;
- obj->shm_fd_ownership = 1;
-
- /* The write end of the pipe needs to be non-blocking */
- ret = fcntl(obj->wait_fd[1], F_SETFL, O_NONBLOCK);
- if (ret < 0) {
- PERROR("fcntl");
- goto error_fcntl;
- }
-
- /* memory_map: mmap */
- memory_map = mmap(NULL, memory_map_size, PROT_READ | PROT_WRITE,
- MAP_SHARED | LTTNG_MAP_POPULATE, shm_fd, 0);
- if (memory_map == MAP_FAILED) {
- PERROR("mmap");
- goto error_mmap;
- }
- obj->type = SHM_OBJECT_SHM;
- obj->memory_map = memory_map;
- obj->memory_map_size = memory_map_size;
- obj->allocated_len = memory_map_size;
- obj->index = table->allocated_len++;
-
- return obj;
-
-error_fcntl:
-error_mmap:
- return NULL;
-}
-
-/*
- * Passing ownership of mem to object.
- */
-struct shm_object *shm_object_table_append_mem(struct shm_object_table *table,
- void *mem, size_t memory_map_size, int wakeup_fd)
-{
- struct shm_object *obj;
- int ret;
-
- if (table->allocated_len >= table->size)
- return NULL;
- obj = &table->objects[table->allocated_len];
-
- obj->wait_fd[0] = -1; /* read end is unset */
- obj->wait_fd[1] = wakeup_fd;
- obj->shm_fd = -1;
- obj->shm_fd_ownership = 0;
-
- ret = fcntl(obj->wait_fd[1], F_SETFD, FD_CLOEXEC);
- if (ret < 0) {
- PERROR("fcntl");
- goto error_fcntl;
- }
- /* The write end of the pipe needs to be non-blocking */
- ret = fcntl(obj->wait_fd[1], F_SETFL, O_NONBLOCK);
- if (ret < 0) {
- PERROR("fcntl");
- goto error_fcntl;
- }
-
- obj->type = SHM_OBJECT_MEM;
- obj->memory_map = mem;
- obj->memory_map_size = memory_map_size;
- obj->allocated_len = memory_map_size;
- obj->index = table->allocated_len++;
-
- return obj;
-
-error_fcntl:
- return NULL;
-}
-
-static
-void shmp_object_destroy(struct shm_object *obj, int consumer)
-{
- switch (obj->type) {
- case SHM_OBJECT_SHM:
- {
- int ret, i;
-
- ret = munmap(obj->memory_map, obj->memory_map_size);
- if (ret) {
- PERROR("umnmap");
- assert(0);
- }
-
- if (obj->shm_fd_ownership) {
- /* Delete FDs only if called from app (not consumer). */
- if (!consumer) {
- lttng_ust_lock_fd_tracker();
- ret = close(obj->shm_fd);
- if (!ret) {
- lttng_ust_delete_fd_from_tracker(obj->shm_fd);
- } else {
- PERROR("close");
- assert(0);
- }
- lttng_ust_unlock_fd_tracker();
- } else {
- ret = close(obj->shm_fd);
- if (ret) {
- PERROR("close");
- assert(0);
- }
- }
- }
- for (i = 0; i < 2; i++) {
- if (obj->wait_fd[i] < 0)
- continue;
- if (!consumer) {
- lttng_ust_lock_fd_tracker();
- ret = close(obj->wait_fd[i]);
- if (!ret) {
- lttng_ust_delete_fd_from_tracker(obj->wait_fd[i]);
- } else {
- PERROR("close");
- assert(0);
- }
- lttng_ust_unlock_fd_tracker();
- } else {
- ret = close(obj->wait_fd[i]);
- if (ret) {
- PERROR("close");
- assert(0);
- }
- }
- }
- break;
- }
- case SHM_OBJECT_MEM:
- {
- int ret, i;
-
- for (i = 0; i < 2; i++) {
- if (obj->wait_fd[i] < 0)
- continue;
- if (!consumer) {
- lttng_ust_lock_fd_tracker();
- ret = close(obj->wait_fd[i]);
- if (!ret) {
- lttng_ust_delete_fd_from_tracker(obj->wait_fd[i]);
- } else {
- PERROR("close");
- assert(0);
- }
- lttng_ust_unlock_fd_tracker();
- } else {
- ret = close(obj->wait_fd[i]);
- if (ret) {
- PERROR("close");
- assert(0);
- }
- }
- }
- free(obj->memory_map);
- break;
- }
- default:
- assert(0);
- }
-}
-
-void shm_object_table_destroy(struct shm_object_table *table, int consumer)
-{
- int i;
-
- for (i = 0; i < table->allocated_len; i++)
- shmp_object_destroy(&table->objects[i], consumer);
- free(table);
-}
-
-/*
- * zalloc_shm - allocate memory within a shm object.
- *
- * Shared memory is already zeroed by shmget.
- * *NOT* multithread-safe (should be protected by mutex).
- * Returns a -1, -1 tuple on error.
- */
-struct shm_ref zalloc_shm(struct shm_object *obj, size_t len)
-{
- struct shm_ref ref;
- struct shm_ref shm_ref_error = { -1, -1 };
-
- if (obj->memory_map_size - obj->allocated_len < len)
- return shm_ref_error;
- ref.index = obj->index;
- ref.offset = obj->allocated_len;
- obj->allocated_len += len;
- return ref;
-}
-
-void align_shm(struct shm_object *obj, size_t align)
-{
- size_t offset_len = lttng_ust_offset_align(obj->allocated_len, align);
- obj->allocated_len += offset_len;
-}
projects / lttng-ust.git / blobdiff