Author: markj Date: Tue May 12 14:01:14 2020 New Revision: 360962 URL: https://svnweb.freebsd.org/changeset/base/360962
Log: MFC r360438: Make sendfile(SF_SYNC)'s CV wait interruptible. Modified: stable/12/sys/kern/kern_sendfile.c Directory Properties: stable/12/ (props changed) Modified: stable/12/sys/kern/kern_sendfile.c ============================================================================== --- stable/12/sys/kern/kern_sendfile.c Tue May 12 14:01:12 2020 (r360961) +++ stable/12/sys/kern/kern_sendfile.c Tue May 12 14:01:14 2020 (r360962) @@ -95,8 +95,36 @@ struct sendfile_sync { struct mtx mtx; struct cv cv; unsigned count; + bool waiting; }; +static void +sendfile_sync_destroy(struct sendfile_sync *sfs) +{ + KASSERT(sfs->count == 0, ("sendfile sync %p still busy", sfs)); + + cv_destroy(&sfs->cv); + mtx_destroy(&sfs->mtx); + free(sfs, M_SENDFILE); +} + +static void +sendfile_sync_signal(struct sendfile_sync *sfs) +{ + mtx_lock(&sfs->mtx); + KASSERT(sfs->count > 0, ("sendfile sync %p not busy", sfs)); + if (--sfs->count == 0) { + if (!sfs->waiting) { + /* The sendfile() waiter was interrupted by a signal. */ + sendfile_sync_destroy(sfs); + return; + } else { + cv_signal(&sfs->cv); + } + } + mtx_unlock(&sfs->mtx); +} + counter_u64_t sfstat[sizeof(struct sfstat) / sizeof(uint64_t)]; static void @@ -140,12 +168,7 @@ sendfile_free_mext(struct mbuf *m) if (m->m_ext.ext_flags & EXT_FLAG_SYNC) { struct sendfile_sync *sfs = m->m_ext.ext_arg2; - - mtx_lock(&sfs->mtx); - KASSERT(sfs->count > 0, ("Sendfile sync botchup count == 0")); - if (--sfs->count == 0) - cv_signal(&sfs->cv); - mtx_unlock(&sfs->mtx); + sendfile_sync_signal(sfs); } } @@ -535,6 +558,7 @@ vn_sendfile(struct file *fp, int sockfd, struct uio *h sfs = malloc(sizeof(*sfs), M_SENDFILE, M_WAITOK | M_ZERO); mtx_init(&sfs->mtx, "sendfile", NULL, MTX_DEF); cv_init(&sfs->cv, "sendfile"); + sfs->waiting = true; } rem = nbytes ? omin(nbytes, obj_size - offset) : obj_size - offset; @@ -896,11 +920,13 @@ out: if (sfs != NULL) { mtx_lock(&sfs->mtx); if (sfs->count != 0) - cv_wait(&sfs->cv, &sfs->mtx); - KASSERT(sfs->count == 0, ("sendfile sync still busy")); - cv_destroy(&sfs->cv); - mtx_destroy(&sfs->mtx); - free(sfs, M_SENDFILE); + error = cv_wait_sig(&sfs->cv, &sfs->mtx); + if (sfs->count == 0) { + sendfile_sync_destroy(sfs); + } else { + sfs->waiting = false; + mtx_unlock(&sfs->mtx); + } } if (error == ERESTART) _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"