56 static	dp_entry_t	**devpolltbl;	/* dev poll entries */
60 int			devpoll_init;	/* is /dev/poll initialized already */
86 	dppoll,			/* poll */
117 	"/dev/poll driver",
136  * The /dev/poll driver shares most of its code with poll sys call whose
137  * code is in common/syscall/poll.c. In poll(2) design, the pollcache
140  * poll(2) design, no lwp will ever need to grow bitmap of other lwp.
141  * This assumption is not true for /dev/poll; hence the need for extra
144  * To allow more parallelism, each /dev/poll file descriptor (indexed by
147  * /dev/poll fd. However, we prevent writes from being starved by giving
151  * content of poll fd a cache set. If writes happens so often that they
196 	if (ddi_create_minor_node(devi, "poll", S_IFCHR, 0, DDI_PSEUDO, 0)  in dpattach()
237  * dp_pcache_poll has similar logic to pcache_poll() in poll.c. The major
238  * differences are: (1) /dev/poll requires scanning the bitmap starting at
244  * NOTE: Upon closing an fd, automatic poll cache cleanup is done for
245  *	 poll(2) caches but NOT for /dev/poll caches. So expect some
261 		/* No Need to search because no poll fd has been cached. */  in dp_pcache_poll()
347 					 * is consistent with poll(2) polling a  in dp_pcache_poll()
398 					 * Regular /dev/poll is unbothered  in dp_pcache_poll()
424 			 * poll routine to change. May want to revisit  in dp_pcache_poll()
496 					 * which poll and epoll representations  in dp_pcache_poll()
591 				 * We clear a bit or cache a poll fd if  in dp_pcache_poll()
592 				 * the driver returns a poll head ptr,  in dp_pcache_poll()
683 	 * dpwrite() or attempt to poll on the instance, allowing parents  in dpopen()
684 	 * to create instances of /dev/poll for their children.  (In the  in dpopen()
701  * Write to dev/poll add/remove fd's to/from a cached poll fd set,
702  * or change poll events for a watched fd.
789 	 * Although /dev/poll uses the write(2) interface to cache fds, it's  in dpwrite()
834 		 * Non-epoll writers to /dev/poll handles can tolerate EINTR.  in dpwrite()
859 	 * Since the dpwrite() may recursively walk an added /dev/poll handle,  in dpwrite()
973 				 * with same poll events.  in dpwrite()
987 			 * do VOP_POLL and cache this poll fd.  in dpwrite()
997 			 * poll routine to change. May want to revisit  in dpwrite()
1032 			 * this forces the first DP_POLL to poll this fd.  in dpwrite()
1083 	 * /dev/poll handles. To ensure that proper event propagation occurs,  in dpwrite()
1368 			 * marked as valid during the poll.  in dpioctl()
1399 			 * break the loop, else poll again.  in dpioctl()
1441 			 * No Need to search because no poll fd  in dpioctl()
1478  * It is possible for /dev/poll to poll for events on file descriptors which
1479  * themselves are /dev/poll handles.  Pending events in the child handle are
1481  * this recursion is presently allowed on only /dev/poll handles which have
1487  * The recursive /dev/poll implementation begins by extending dppoll() to
1494  * which corresponds to the child /dev/poll fd.  This means that child
1495  * pollcaches will be checked during every poll which facilitates wake-up
1500  * Recursive /dev/poll avoids complicated pollcache locking constraints during
1503  * /dev/poll "tree", pcachelink_t structures are established to all child
1504  * /dev/poll pollcaches.  During pollnotify() in a child pollcache, the
1509  * still allows the woken poll on the parent to discover the pertinent events
1518  * to the end if no match (and therefore loop) is found.  Once poll operations
1525  * Descending through a tree of recursive /dev/poll handles involves the tricky
1529  * pollstate_exit() functions provide an interface for recursive /dev/poll
1554 		/* Poll recursion is not yet supported for non-epoll handles */  in dppoll()
1617  * reference of this /dev/poll fd can close.
1641 	 * /dev/poll fd. This pollcache is going away, so do the clean  in dpclose()
1661 	/* Clean up any pollcache links created via recursive /dev/poll */  in dpclose()