0001420: pbd/ringbuffer.h is incorrect for some 64 bit arches: sizeof(gint) != sizeof(size_t)

ID	Project	Category	View Status	Date Submitted	Last Update

0001420	ardour	bugs	public	2007-01-12 04:35	2007-01-12 04:35

Reporter	mtaht	Assigned To
Priority	normal	Severity	minor	Reproducibility	always
Status	new	Resolution	open

Summary	0001420: pbd/ringbuffer.h is incorrect for some 64 bit arches: sizeof(gint) != sizeof(size_t)
Description	presently the ringbuffe*.h includes are incorrect for some 64 bit architectures. secondly write_ptr and read_ptr are actually indexes. thirdly, few places in this code actually need or can use a size_t size, so you could gain benefits by cutting the sizes down to ints... also.... In looking over the range of the ringbuffers in use, I didn't see any that were greater than 2^16, so the atomic operations could be cut down to a struct of two shorts unioned with int and made completely atomic (with either 16 bit atomic ops or a 32 bit atomic compare and exchange operation) (or, moved to different cache lines entirely to reduce cache invalidations on smp arches)... (there are also 64 bit atomic operations available on most arches. See the linux kernel source for complete information in the various atomic header files)
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Date Modified	Username	Field	Change
2007-01-12 04:35	mtaht	New Issue