/* * An implementation of host to guest copy functionality for Linux. * * Copyright (C) 2014, Microsoft, Inc. * * Author : K. Y. Srinivasan * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published * by the Free Software Foundation. * * This program 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, GOOD TITLE or * NON INFRINGEMENT. See the GNU General Public License for more * details. */ #include #include #include #include #include #include #include #include #include #include static int target_fd; static char target_fname[W_MAX_PATH]; static unsigned long long filesize; static int hv_start_fcopy(struct hv_start_fcopy *smsg) { int error = HV_E_FAIL; char *q, *p; filesize = 0; p = (char *)smsg->path_name; snprintf(target_fname, sizeof(target_fname), "%s/%s", (char *)smsg->path_name, (char *)smsg->file_name); syslog(LOG_INFO, "Target file name: %s", target_fname); /* * Check to see if the path is already in place; if not, * create if required. */ while ((q = strchr(p, '/')) != NULL) { if (q == p) { p++; continue; } *q = '\0'; if (access((char *)smsg->path_name, F_OK)) { if (smsg->copy_flags & CREATE_PATH) { if (mkdir((char *)smsg->path_name, 0755)) { syslog(LOG_ERR, "Failed to create %s", (char *)smsg->path_name); goto done; } } else { syslog(LOG_ERR, "Invalid path: %s", (char *)smsg->path_name); goto done; } } p = q + 1; *q = '/'; } if (!access(target_fname, F_OK)) { syslog(LOG_INFO, "File: %s exists", target_fname); if (!(smsg->copy_flags & OVER_WRITE)) { error = HV_ERROR_ALREADY_EXISTS; goto done; } } target_fd = open(target_fname, O_RDWR | O_CREAT | O_TRUNC | O_CLOEXEC, 0744); if (target_fd == -1) { syslog(LOG_INFO, "Open Failed: %s", strerror(errno)); goto done; } error = 0; done: return error; } static int hv_copy_data(struct hv_do_fcopy *cpmsg) { ssize_t bytes_written; int ret = 0; bytes_written = pwrite(target_fd, cpmsg->data, cpmsg->size, cpmsg->offset); filesize += cpmsg->size; if (bytes_written != cpmsg->size) { switch (errno) { case ENOSPC: ret = HV_ERROR_DISK_FULL; break; default: ret = HV_E_FAIL; break; } syslog(LOG_ERR, "pwrite failed to write %llu bytes: %ld (%s)", filesize, (long)bytes_written, strerror(errno)); } return ret; } static int hv_copy_finished(void) { close(target_fd); return 0; } static int hv_copy_cancel(void) { close(target_fd); unlink(target_fname); return 0; } void print_usage(char *argv[]) { fprintf(stderr, "Usage: %s [options]\n" "Options are:\n" " -n, --no-daemon stay in foreground, don't daemonize\n" " -h, --help print this help\n", argv[0]); } int main(int argc, char *argv[]) { int fcopy_fd, len; int error; int daemonize = 1, long_index = 0, opt; int version = FCOPY_CURRENT_VERSION; char *buffer[4096 * 2]; struct hv_fcopy_hdr *in_msg; int in_handshake = 1; __u32 kernel_modver; static struct option long_options[] = { {"help", no_argument, 0, 'h' }, {"no-daemon", no_argument, 0, 'n' }, {0, 0, 0, 0 } }; while ((opt = getopt_long(argc, argv, "hn", long_options, &long_index)) != -1) { switch (opt) { case 'n': daemonize = 0; break; case 'h': default: print_usage(argv); exit(EXIT_FAILURE); } } if (daemonize && daemon(1, 0)) { syslog(LOG_ERR, "daemon() failed; error: %s", strerror(errno)); exit(EXIT_FAILURE); } openlog("HV_FCOPY", 0, LOG_USER); syslog(LOG_INFO, "starting; pid is:%d", getpid()); fcopy_fd = open("/dev/vmbus/hv_fcopy", O_RDWR); if (fcopy_fd < 0) { syslog(LOG_ERR, "open /dev/vmbus/hv_fcopy failed; error: %d %s", errno, strerror(errno)); exit(EXIT_FAILURE); } /* * Register with the kernel. */ if ((write(fcopy_fd, &version, sizeof(int))) != sizeof(int)) { syslog(LOG_ERR, "Registration failed: %s", strerror(errno)); exit(EXIT_FAILURE); } while (1) { /* * In this loop we process fcopy messages after the * handshake is complete. */ len = pread(fcopy_fd, buffer, (4096 * 2), 0); if (len < 0) { syslog(LOG_ERR, "pread failed: %s", strerror(errno)); exit(EXIT_FAILURE); } if (in_handshake) { if (len != sizeof(kernel_modver)) { syslog(LOG_ERR, "invalid version negotiation"); exit(EXIT_FAILURE); } kernel_modver = *(__u32 *)buffer; in_handshake = 0; syslog(LOG_INFO, "kernel module version: %d", kernel_modver); continue; } in_msg = (struct hv_fcopy_hdr *)buffer; switch (in_msg->operation) { case START_FILE_COPY: error = hv_start_fcopy((struct hv_start_fcopy *)in_msg); break; case WRITE_TO_FILE: error = hv_copy_data((struct hv_do_fcopy *)in_msg); break; case COMPLETE_FCOPY: error = hv_copy_finished(); break; case CANCEL_FCOPY: error = hv_copy_cancel(); break; default: syslog(LOG_ERR, "Unknown operation: %d", in_msg->operation); } if (pwrite(fcopy_fd, &error, sizeof(int), 0) != sizeof(int)) { syslog(LOG_ERR, "pwrite failed: %s", strerror(errno)); exit(EXIT_FAILURE); } } } inux/net-next.git/commit/tools/power/acpi/Makefile.config?h=nds-private-remove&id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>79c6f448c8b79c321e4a1f31f98194e4f6b6cae7 (patch) tree370efda701f03cccf21e02bb1fdd3b852547d75c /tools/power/acpi/Makefile.config parent0c744ea4f77d72b3dcebb7a8f2684633ec79be88 (diff)
tracing: Fix hwlat kthread migration
The hwlat tracer creates a kernel thread at start of the tracer. It is pinned to a single CPU and will move to the next CPU after each period of running. If the user modifies the migration thread's affinity, it will not change after that happens. The original code created the thread at the first instance it was called, but later was changed to destroy the thread after the tracer was finished, and would not be created until the next instance of the tracer was established. The code that initialized the affinity was only called on the initial instantiation of the tracer. After that, it was not initialized, and the previous affinity did not match the current newly created one, making it appear that the user modified the thread's affinity when it did not, and the thread failed to migrate again. Cc: stable@vger.kernel.org Fixes: 0330f7aa8ee6 ("tracing: Have hwlat trace migrate across tracing_cpumask CPUs") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'tools/power/acpi/Makefile.config')