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Merge branch 'develop' into dcb_code_revert

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This commit is contained in:
Markus Makela
2015-08-20 12:06:14 +03:00
parent 4e5968ee15 80691ab080
commit d1bf6bb303
10 changed files with 100 additions and 37 deletions
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40
server/core/gwbitmask.c
View File

@ -20,20 +20,33 @@
#include <gwbitmask.h>
/**
* @file gwbitmask.c Implementation of bitmask opertions for the gateway
* @file gwbitmask.c Implementation of bitmask operations for the gateway
*
* We provide basic bitmask manipulation routines, the size of
* the bitmask will grow dynamically based on the highest bit
* number that is set or cleared within the bitmask.
*
* Bitmsk growth happens in increments rather than via a single bit as
* Bitmask growth happens in increments rather than via a single bit as
* a time.
*
* Please note limitations to these mechanisms:
*
* 1. The initial size and increment size MUST be exact multiples of 8
* 2. Only suitable for a compact set of bit numbers i.e. the numbering
* needs to start near to 0 and grow without sizeable gaps
* 3. It is assumed that a bit number bigger than the current size can
* be accommodated by adding a single extra block of bits
* 4. During copy, if memory cannot be allocated, a zero length bitmap is
* created as the destination. This will test true for all bits clear, which
* may be a serious error. However, the memory requirement is very small and
* is only likely to fail in circumstances where a lot else is going wrong.
*
* @verbatim
* Revision History
*
* Date Who Description
* Date Who Description
* 28/06/13 Mark Riddoch Initial implementation
* 20/08/15 Martin Brampton Added caveats about limitations (above)
*
* @endverbatim
*/
@ -42,7 +55,7 @@
* Initialise a bitmask
*
* @param bitmask Pointer the bitmask
* @return The value of *variable before the add occured
* @return The value of *variable before the add occurred
*/
void
bitmask_init(GWBITMASK *bitmask)
@ -77,7 +90,9 @@ bitmask_free(GWBITMASK *bitmask)
/**
* Set the bit at the specified bit position in the bitmask.
* The bitmask will automatically be extended if the bit is
* beyond the current bitmask length
* beyond the current bitmask length. Note that growth is only
* by a single increment - the bit numbers used need to be a
* fairly dense set.
*
* @param bitmask Pointer the bitmask
* @param bit Bit to set
@ -106,7 +121,9 @@ unsigned char mask;
/**
* Clear the bit at the specified bit position in the bitmask.
* The bitmask will automatically be extended if the bit is
* beyond the current bitmask length
* beyond the current bitmask length. This could be optimised
* by always assuming that a bit beyond the current length is
* unset (i.e. 0) and not extending the actual bitmask.
*
* @param bitmask Pointer the bitmask
* @param bit Bit to clear
@ -134,7 +151,8 @@ unsigned char mask;
* Return a non-zero value if the bit at the specified bit
* position in the bitmask is set.
* The bitmask will automatically be extended if the bit is
* beyond the current bitmask length
* beyond the current bitmask length. This could be optimised
* by assuming that a bit beyond the length is unset.
*
* @param bitmask Pointer the bitmask
* @param bit Bit to clear
@ -162,7 +180,9 @@ unsigned char mask;
/**
* Return a non-zero value of the bitmask has no bits set
* in it.
* in it. This logic could be defeated if the bitmask is a
* copy and there was insufficient memory when the copy was
* made.
*
* @param bitmask Pointer the bitmask
* @return Non-zero if the bitmask has no bits set
@ -191,6 +211,10 @@ unsigned char *ptr, *eptr;
/**
* Copy the contents of one bitmap to another.
*
* On memory failure, a zero length bitmask is created in the destination,
* which could seriously undermine the logic. Given the small size of the
* bitmask, this is unlikely to happen.
*
* @param dest Bitmap tp update
* @param src Bitmap to copy

12
server/core/poll.c
View File

@ -339,7 +339,7 @@ poll_add_dcb(DCB *dcb)
int
poll_remove_dcb(DCB *dcb)
{
int rc = -1;
int dcbfd, rc = -1;
struct epoll_event ev;
CHK_DCB(dcb);
@ -362,11 +362,14 @@ poll_remove_dcb(DCB *dcb)
dcb,
STRDCBSTATE(dcb->state))));
}
/*< Set bit for each maxscale thread. This should be done before
* the state is changed, so as to protect the DCB from premature
* destruction. */
bitmask_copy(&dcb->memdata.bitmask, poll_bitmask());
/*<
* Set state to NOPOLLING and remove dcb from poll set.
*/
dcb->state = DCB_STATE_NOPOLLING;
spinlock_release(&dcb->dcb_initlock);
/**
* Only positive fds can be removed from epoll set.
@ -375,8 +378,9 @@ poll_remove_dcb(DCB *dcb)
* only action for them is already done - the change of state to
* DCB_STATE_NOPOLLING.
*/
dcbfd = dcb->fd;
spinlock_release(&dcb->dcb_initlock);
if (dcb->fd > 0)
if (dcbfd > 0)
{
rc = epoll_ctl(epoll_fd, EPOLL_CTL_DEL, dcb->fd, &ev);
/**
@ -386,8 +390,6 @@ poll_remove_dcb(DCB *dcb)
*/
if (rc) rc = poll_resolve_error(dcb, errno, false);
if (rc) raise(SIGABRT);
/*< Set bit for each maxscale thread */
bitmask_copy(&dcb->memdata.bitmask, poll_bitmask());
}
return rc;
}