MEDIUM: fd/threads: only grab the fd's lock if the FD has more than one thread
The vast majority of FDs are only seen by one thread. Currently the lock
on FDs costs a lot because it's touched often, though there should be very
little contention. This patch ensures that the lock is only grabbed if the
FD is shared by more than one thread, since otherwise the situation is safe.
Doing so resulted in a 15% performance boost on a 12-threads test.
diff --git a/include/proto/fd.h b/include/proto/fd.h
index a3ec5e8..7123377 100644
--- a/include/proto/fd.h
+++ b/include/proto/fd.h
@@ -289,9 +289,11 @@
if ((old ^ new) & FD_EV_POLLED_R)
updt_fd_polling(fd);
- HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
fd_update_cache(fd); /* need an update entry to change the state */
- HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
}
/* Disable processing send events on fd <fd> */
@@ -310,9 +312,11 @@
if ((old ^ new) & FD_EV_POLLED_W)
updt_fd_polling(fd);
- HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
fd_update_cache(fd); /* need an update entry to change the state */
- HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
}
/* Disable processing of events on fd <fd> for both directions. */
@@ -331,9 +335,11 @@
if ((old ^ new) & FD_EV_POLLED_RW)
updt_fd_polling(fd);
- HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
fd_update_cache(fd); /* need an update entry to change the state */
- HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
}
/* Report that FD <fd> cannot receive anymore without polling (EAGAIN detected). */
@@ -353,9 +359,11 @@
if ((old ^ new) & FD_EV_POLLED_R)
updt_fd_polling(fd);
- HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
fd_update_cache(fd); /* need an update entry to change the state */
- HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
}
/* Report that FD <fd> can receive anymore without polling. */
@@ -364,9 +372,11 @@
/* marking ready never changes polled status */
HA_ATOMIC_OR(&fdtab[fd].state, FD_EV_READY_R);
- HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
fd_update_cache(fd); /* need an update entry to change the state */
- HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
}
/* Disable readiness when polled. This is useful to interrupt reading when it
@@ -390,9 +400,11 @@
if ((old ^ new) & FD_EV_POLLED_R)
updt_fd_polling(fd);
- HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
fd_update_cache(fd); /* need an update entry to change the state */
- HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
}
/* Report that FD <fd> cannot send anymore without polling (EAGAIN detected). */
@@ -412,9 +424,11 @@
if ((old ^ new) & FD_EV_POLLED_W)
updt_fd_polling(fd);
- HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
fd_update_cache(fd); /* need an update entry to change the state */
- HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
}
/* Report that FD <fd> can send anymore without polling (EAGAIN detected). */
@@ -423,9 +437,11 @@
/* marking ready never changes polled status */
HA_ATOMIC_OR(&fdtab[fd].state, FD_EV_READY_W);
- HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
fd_update_cache(fd); /* need an update entry to change the state */
- HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
}
/* Prepare FD <fd> to try to receive */
@@ -445,9 +461,11 @@
if ((old ^ new) & FD_EV_POLLED_R)
updt_fd_polling(fd);
- HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
fd_update_cache(fd); /* need an update entry to change the state */
- HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
}
/* Prepare FD <fd> to try to send */
@@ -467,19 +485,23 @@
if ((old ^ new) & FD_EV_POLLED_W)
updt_fd_polling(fd);
- HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
fd_update_cache(fd); /* need an update entry to change the state */
- HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
}
/* Update events seen for FD <fd> and its state if needed. This should be called
* by the poller to set FD_POLL_* flags. */
static inline void fd_update_events(int fd, int evts)
{
- HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
fdtab[fd].ev &= FD_POLL_STICKY;
fdtab[fd].ev |= evts;
- HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(fdtab[fd].thread_mask))
+ HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
if (fdtab[fd].ev & (FD_POLL_IN | FD_POLL_HUP | FD_POLL_ERR))
fd_may_recv(fd);
@@ -491,7 +513,8 @@
/* Prepares <fd> for being polled */
static inline void fd_insert(int fd, void *owner, void (*iocb)(int fd), unsigned long thread_mask)
{
- HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(thread_mask))
+ HA_SPIN_LOCK(FD_LOCK, &fdtab[fd].lock);
fdtab[fd].owner = owner;
fdtab[fd].iocb = iocb;
fdtab[fd].ev = 0;
@@ -501,7 +524,8 @@
/* note: do not reset polled_mask here as it indicates which poller
* still knows this FD from a possible previous round.
*/
- HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
+ if (atleast2(thread_mask))
+ HA_SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock);
}
/* These are replacements for FD_SET, FD_CLR, FD_ISSET, working on uints */