perf-eh_elf/util/trigger.h
Linus Torvalds 16c00db4bb Merge tag 'afs-fixes-20180514' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull AFS fixes from David Howells:
 "Here's a set of patches that fix a number of bugs in the in-kernel AFS
  client, including:

   - Fix directory locking to not use individual page locks for
     directory reading/scanning but rather to use a semaphore on the
     afs_vnode struct as the directory contents must be read in a single
     blob and data from different reads must not be mixed as the entire
     contents may be shuffled about between reads.

   - Fix address list parsing to handle port specifiers correctly.

   - Only give up callback records on a server if we actually talked to
     that server (we might not be able to access a server).

   - Fix some callback handling bugs, including refcounting,
     whole-volume callbacks and when callbacks actually get broken in
     response to a CB.CallBack op.

   - Fix some server/address rotation bugs, including giving up if we
     can't probe a server; giving up if a server says it doesn't have a
     volume, but there are more servers to try.

   - Fix the decoding of fetched statuses to be OpenAFS compatible.

   - Fix the handling of server lookups in Cache Manager ops (such as
     CB.InitCallBackState3) to use a UUID if possible and to handle no
     server being found.

   - Fix a bug in server lookup where not all addresses are compared.

   - Fix the non-encryption of calls that prevents some servers from
     being accessed (this also requires an AF_RXRPC patch that has
     already gone in through the net tree).

  There's also a patch that adds tracepoints to log Cache Manager ops
  that don't find a matching server, either by UUID or by address"

* tag 'afs-fixes-20180514' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Fix the non-encryption of calls
  afs: Fix CB.CallBack handling
  afs: Fix whole-volume callback handling
  afs: Fix afs_find_server search loop
  afs: Fix the handling of an unfound server in CM operations
  afs: Add a tracepoint to record callbacks from unlisted servers
  afs: Fix the handling of CB.InitCallBackState3 to find the server by UUID
  afs: Fix VNOVOL handling in address rotation
  afs: Fix AFSFetchStatus decoder to provide OpenAFS compatibility
  afs: Fix server rotation's handling of fileserver probe failure
  afs: Fix refcounting in callback registration
  afs: Fix giving up callbacks on server destruction
  afs: Fix address list parsing
  afs: Fix directory page locking
2018-05-15 10:48:36 -07:00

97 lines
2 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __TRIGGER_H_
#define __TRIGGER_H_ 1
#include "util/debug.h"
#include "asm/bug.h"
/*
* Use trigger to model operations which need to be executed when
* an event (a signal, for example) is observed.
*
* States and transits:
*
*
* OFF--> ON --> READY --(hit)--> HIT
* ^ |
* | (ready)
* | |
* \_____________/
*
* is_hit and is_ready are two key functions to query the state of
* a trigger. is_hit means the event already happen; is_ready means the
* trigger is waiting for the event.
*/
struct trigger {
volatile enum {
TRIGGER_ERROR = -2,
TRIGGER_OFF = -1,
TRIGGER_ON = 0,
TRIGGER_READY = 1,
TRIGGER_HIT = 2,
} state;
const char *name;
};
#define TRIGGER_WARN_ONCE(t, exp) \
WARN_ONCE(t->state != exp, "trigger '%s' state transist error: %d in %s()\n", \
t->name, t->state, __func__)
static inline bool trigger_is_available(struct trigger *t)
{
return t->state >= 0;
}
static inline bool trigger_is_error(struct trigger *t)
{
return t->state <= TRIGGER_ERROR;
}
static inline void trigger_on(struct trigger *t)
{
TRIGGER_WARN_ONCE(t, TRIGGER_OFF);
t->state = TRIGGER_ON;
}
static inline void trigger_ready(struct trigger *t)
{
if (!trigger_is_available(t))
return;
t->state = TRIGGER_READY;
}
static inline void trigger_hit(struct trigger *t)
{
if (!trigger_is_available(t))
return;
TRIGGER_WARN_ONCE(t, TRIGGER_READY);
t->state = TRIGGER_HIT;
}
static inline void trigger_off(struct trigger *t)
{
if (!trigger_is_available(t))
return;
t->state = TRIGGER_OFF;
}
static inline void trigger_error(struct trigger *t)
{
t->state = TRIGGER_ERROR;
}
static inline bool trigger_is_ready(struct trigger *t)
{
return t->state == TRIGGER_READY;
}
static inline bool trigger_is_hit(struct trigger *t)
{
return t->state == TRIGGER_HIT;
}
#define DEFINE_TRIGGER(n) \
struct trigger n = {.state = TRIGGER_OFF, .name = #n}
#endif