#include #include #include #include #include #include #include "data.h" #include "util.h" #include "debug.h" static bool check_pipe(struct perf_data_file *file) { struct stat st; bool is_pipe = false; int fd = perf_data_file__is_read(file) ? STDIN_FILENO : STDOUT_FILENO; if (!file->path) { if (!fstat(fd, &st) && S_ISFIFO(st.st_mode)) is_pipe = true; } else { if (!strcmp(file->path, "-")) is_pipe = true; } if (is_pipe) file->fd = fd; return file->is_pipe = is_pipe; } static int check_backup(struct perf_data_file *file) { struct stat st; if (!stat(file->path, &st) && st.st_size) { /* TODO check errors properly */ char oldname[PATH_MAX]; snprintf(oldname, sizeof(oldname), "%s.old", file->path); unlink(oldname); rename(file->path, oldname); } return 0; } static int open_file_read(struct perf_data_file *file) { struct stat st; int fd; char sbuf[STRERR_BUFSIZE]; fd = open(file->path, O_RDONLY); if (fd < 0) { int err = errno; pr_err("failed to open %s: %s", file->path, str_error_r(err, sbuf, sizeof(sbuf))); if (err == ENOENT && !strcmp(file->path, "perf.data")) pr_err(" (try 'perf record' first)"); pr_err("\n"); return -err; } if (fstat(fd, &st) < 0) goto out_close; if (!file->force && st.st_uid && (st.st_uid != geteuid())) { pr_err("File %s not owned by current user or root (use -f to override)\n", file->path); goto out_close; } if (!st.st_size) { pr_info("zero-sized file (%s), nothing to do!\n", file->path); goto out_close; } file->size = st.st_size; return fd; out_close: close(fd); return -1; } static int open_file_write(struct perf_data_file *file) { int fd; char sbuf[STRERR_BUFSIZE]; if (check_backup(file)) return -1; fd = open(file->path, O_CREAT|O_RDWR|O_TRUNC, S_IRUSR|S_IWUSR); if (fd < 0) pr_err("failed to open %s : %s\n", file->path, str_error_r(errno, sbuf, sizeof(sbuf))); return fd; } static int open_file(struct perf_data_file *file) { int fd; fd = perf_data_file__is_read(file) ? open_file_read(file) : open_file_write(file); file->fd = fd; return fd < 0 ? -1 : 0; } int perf_data_file__open(struct perf_data_file *file) { if (check_pipe(file)) return 0; if (!file->path) file->path = "perf.data"; return open_file(file); } void perf_data_file__close(struct perf_data_file *file) { close(file->fd); } ssize_t perf_data_file__write(struct perf_data_file *file, void *buf, size_t size) { return writen(file->fd, buf, size); } int perf_data_file__switch(struct perf_data_file *file, const char *postfix, size_t pos, bool at_exit) { char *new_filepath; int ret; if (check_pipe(file)) return -EINVAL; if (perf_data_file__is_read(file)) return -EINVAL; if (asprintf(&new_filepath, "%s.%s", file->path, postfix) < 0) return -ENOMEM; /* * Only fire a warning, don't return error, continue fill * original file. */ if (rename(file->path, new_filepath)) pr_warning("Failed to rename %s to %s\n", file->path, new_filepath); if (!at_exit) { close(file->fd); ret = perf_data_file__open(file); if (ret < 0) goto out; if (lseek(file->fd, pos, SEEK_SET) == (off_t)-1) { ret = -errno; pr_debug("Failed to lseek to %zu: %s", pos, strerror(errno)); goto out; } } ret = file->fd; out: free(new_filepath); return ret; } ass='label'>context:space:mode:

author	Thomas Gleixner <tglx@linutronix.de>	2017-01-31 23:58:38 +0100
committer	Ingo Molnar <mingo@kernel.org>	2017-02-01 08:37:27 +0100
commit	dd86e373e09fb16b83e8adf5c48c421a4ca76468 (patch)
tree	55703c2ea8584e303e342090614e0aab3509ab21 /tools/lib/subcmd/Build
parent	0b3589be9b98994ce3d5aeca52445d1f5627c4ba (diff)

perf/x86/intel/rapl: Make package handling more robust

The package management code in RAPL relies on package mapping being available before a CPU is started. This changed with: 9d85eb9119f4 ("x86/smpboot: Make logical package management more robust") because the ACPI/BIOS information turned out to be unreliable, but that left RAPL in broken state. This was not noticed because on a regular boot all CPUs are online before RAPL is initialized. A possible fix would be to reintroduce the mess which allocates a package data structure in CPU prepare and when it turns out to already exist in starting throw it away later in the CPU online callback. But that's a horrible hack and not required at all because RAPL becomes functional for perf only in the CPU online callback. That's correct because user space is not yet informed about the CPU being onlined, so nothing caan rely on RAPL being available on that particular CPU. Move the allocation to the CPU online callback and simplify the hotplug handling. At this point the package mapping is established and correct. This also adds a missing check for available package data in the event_init() function. Reported-by: Yasuaki Ishimatsu <yasu.isimatu@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Stephane Eranian <eranian@google.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: 9d85eb9119f4 ("x86/smpboot: Make logical package management more robust") Link: http://lkml.kernel.org/r/20170131230141.212593966@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>

Diffstat (limited to 'tools/lib/subcmd/Build')