From 54ee5b3da00cdbee836a06a7e6eb319c895f2a57 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Sun, 17 Apr 2022 11:29:41 -0700 Subject: util/log: Drop manual log buffering MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This buffering was introduced during the Paleozoic: 9fa3e853531. There has never been an explanation as to why we may not allow glibc to allocate the file buffer itself. We certainly have many other uses of mmap and malloc during user-only startup, so presumably whatever the issue was, it has been fixed during the preceeding 18 years. Reviewed-by: Alex Bennée Signed-off-by: Richard Henderson Message-Id: <20220417183019.755276-2-richard.henderson@linaro.org> --- util/log.c | 21 ++++----------------- 1 file changed, 4 insertions(+), 17 deletions(-) (limited to 'util/log.c') diff --git a/util/log.c b/util/log.c index 2ee1500..ffa66a2 100644 --- a/util/log.c +++ b/util/log.c @@ -72,8 +72,6 @@ static void qemu_logfile_free(QemuLogFile *logfile) g_free(logfile); } -static bool log_uses_own_buffers; - /* enable or disable low levels log */ void qemu_set_log(int log_flags) { @@ -121,29 +119,18 @@ void qemu_set_log(int log_flags) assert(!is_daemonized()); logfile->fd = stderr; } - /* must avoid mmap() usage of glibc by setting a buffer "by hand" */ - if (log_uses_own_buffers) { - static char logfile_buf[4096]; - setvbuf(logfile->fd, logfile_buf, _IOLBF, sizeof(logfile_buf)); - } else { #if defined(_WIN32) - /* Win32 doesn't support line-buffering, so use unbuffered output. */ - setvbuf(logfile->fd, NULL, _IONBF, 0); + /* Win32 doesn't support line-buffering, so use unbuffered output. */ + setvbuf(logfile->fd, NULL, _IONBF, 0); #else - setvbuf(logfile->fd, NULL, _IOLBF, 0); + setvbuf(logfile->fd, NULL, _IOLBF, 0); #endif - log_append = 1; - } + log_append = 1; qatomic_rcu_set(&qemu_logfile, logfile); } } -void qemu_log_needs_buffers(void) -{ - log_uses_own_buffers = true; -} - /* * Allow the user to include %d in their logfile which will be * substituted with the current PID. This is useful for debugging many -- cgit v1.1