Commit e6a7d7f7 authored by David Howells's avatar David Howells
Browse files

afs: Dispatch vlserver probes in priority order 



When probing all the addresses for a volume location server, dispatch them
in order of descending priority to try and get back highest priority one
first.

Also add a tracepoint to show the transmission and completion of the
probes.

Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
parent 92f091cd

fs/afs/internal.h

+1 −0
Original line number Diff line number Diff line
@@ -447,6 +447,7 @@ struct afs_vlserver { 
	rwlock_t		lock;		/* Lock on addresses */

	refcount_t		ref;

	unsigned int		rtt;		/* Server's current RTT in uS */

	unsigned int		debug_id;



	/* Probe state */

	wait_queue_head_t	probe_wq;

fs/afs/vl_list.c

+2 −0
Original line number Diff line number Diff line
@@ -13,6 +13,7 @@ struct afs_vlserver *afs_alloc_vlserver(const char *name, size_t name_len, 
					unsigned short port)

{

	struct afs_vlserver *vlserver;

	static atomic_t debug_ids;



	vlserver = kzalloc(struct_size(vlserver, name, name_len + 1),

			   GFP_KERNEL);
@@ -21,6 +22,7 @@ struct afs_vlserver *afs_alloc_vlserver(const char *name, size_t name_len, 
		rwlock_init(&vlserver->lock);

		init_waitqueue_head(&vlserver->probe_wq);

		spin_lock_init(&vlserver->probe_lock);

		vlserver->debug_id = atomic_inc_return(&debug_ids);

		vlserver->rtt = UINT_MAX;

		vlserver->name_len = name_len;

		vlserver->service_id = VL_SERVICE;

fs/afs/vl_probe.c

+18 −2
Original line number Diff line number Diff line
@@ -131,6 +131,7 @@ void afs_vlserver_probe_result(struct afs_call *call) 
out:

	spin_unlock(&server->probe_lock);



	trace_afs_vl_probe(server, false, alist, index, call->error, call->abort_code, rtt_us);

	_debug("probe [%u][%u] %pISpc rtt=%d ret=%d",

	       server_index, index, rxrpc_kernel_remote_addr(addr->peer),

	       rtt_us, ret);
@@ -150,8 +151,10 @@ static bool afs_do_probe_vlserver(struct afs_net *net, 
{

	struct afs_addr_list *alist;

	struct afs_call *call;

	unsigned int index;

	unsigned long unprobed;

	unsigned int index, i;

	bool in_progress = false;

	int best_prio;



	_enter("%s", server->name);
@@ -165,7 +168,20 @@ static bool afs_do_probe_vlserver(struct afs_net *net, 
	memset(&server->probe, 0, sizeof(server->probe));

	server->probe.rtt = UINT_MAX;



	for (index = 0; index < alist->nr_addrs; index++) {

	unprobed = (1UL << alist->nr_addrs) - 1;

	while (unprobed) {

		best_prio = -1;

		index = 0;

		for (i = 0; i < alist->nr_addrs; i++) {

			if (test_bit(i, &unprobed) &&

			    alist->addrs[i].prio > best_prio) {

				index = i;

				best_prio = alist->addrs[i].prio;

			}

		}

		__clear_bit(index, &unprobed);



		trace_afs_vl_probe(server, true, alist, index, 0, 0, 0);

		call = afs_vl_get_capabilities(net, alist, index, key, server,

					       server_index);

		if (!IS_ERR(call)) {

include/trace/events/afs.h

+34 −0
Original line number Diff line number Diff line
@@ -1420,6 +1420,40 @@ TRACE_EVENT(afs_fs_probe, 
		      &__entry->srx.transport)

	    );



TRACE_EVENT(afs_vl_probe,

	    TP_PROTO(struct afs_vlserver *server, bool tx, struct afs_addr_list *alist,

		     unsigned int addr_index, int error, s32 abort_code, unsigned int rtt_us),



	    TP_ARGS(server, tx, alist, addr_index, error, abort_code, rtt_us),



	    TP_STRUCT__entry(

		    __field(unsigned int,		server)

		    __field(bool,			tx)

		    __field(unsigned short,		flags)

		    __field(u16,			addr_index)

		    __field(short,			error)

		    __field(s32,			abort_code)

		    __field(unsigned int,		rtt_us)

		    __field_struct(struct sockaddr_rxrpc, srx)

			     ),



	    TP_fast_assign(

		    __entry->server = server->debug_id;

		    __entry->tx = tx;

		    __entry->addr_index = addr_index;

		    __entry->error = error;

		    __entry->abort_code = abort_code;

		    __entry->rtt_us = rtt_us;

		    memcpy(&__entry->srx, rxrpc_kernel_remote_srx(alist->addrs[addr_index].peer),

			   sizeof(__entry->srx));

			   ),



	    TP_printk("vl=%08x %s ax=%u e=%d ac=%d rtt=%d %pISpc",

		      __entry->server, __entry->tx ? "tx" : "rx", __entry->addr_index,

		      __entry->error, __entry->abort_code, __entry->rtt_us,

		      &__entry->srx.transport)

	    );



#endif /* _TRACE_AFS_H */



/* This part must be outside protection */