 2171a92568
			
		
	
	
	2171a92568
	
	
	
		
			
			We will use this in perf's evlist class so that it can, at
fdarray__filter() time, to unmap the associated ring buffer.
We may need to have further info associated with each fdarray entry, in
that case we'll make that int array a 'union fdarray_priv' one and put a
pointer there so that users can stash whatever they want there. For now,
an int is enough tho.
v2: Add clarification to the per array entry priv area, as well as make
    it a union, which makes usage a bit longer, but if/when we make it
    use more space by allowing per entry pointers existing users source
    code will not have to be changed, just rebuilt.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/n/tip-0p00bn83quck3fio3kcs9vca@git.kernel.org
		
	
			
		
			
				
	
	
		
			127 lines
		
	
	
	
		
			2.4 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			127 lines
		
	
	
	
		
			2.4 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  * Copyright (C) 2014, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
 | |
|  *
 | |
|  * Released under the GPL v2. (and only v2, not any later version)
 | |
|  */
 | |
| #include "array.h"
 | |
| #include <errno.h>
 | |
| #include <fcntl.h>
 | |
| #include <poll.h>
 | |
| #include <stdlib.h>
 | |
| #include <unistd.h>
 | |
| 
 | |
| void fdarray__init(struct fdarray *fda, int nr_autogrow)
 | |
| {
 | |
| 	fda->entries	 = NULL;
 | |
| 	fda->priv	 = NULL;
 | |
| 	fda->nr		 = fda->nr_alloc = 0;
 | |
| 	fda->nr_autogrow = nr_autogrow;
 | |
| }
 | |
| 
 | |
| int fdarray__grow(struct fdarray *fda, int nr)
 | |
| {
 | |
| 	void *priv;
 | |
| 	int nr_alloc = fda->nr_alloc + nr;
 | |
| 	size_t psize = sizeof(fda->priv[0]) * nr_alloc;
 | |
| 	size_t size  = sizeof(struct pollfd) * nr_alloc;
 | |
| 	struct pollfd *entries = realloc(fda->entries, size);
 | |
| 
 | |
| 	if (entries == NULL)
 | |
| 		return -ENOMEM;
 | |
| 
 | |
| 	priv = realloc(fda->priv, psize);
 | |
| 	if (priv == NULL) {
 | |
| 		free(entries);
 | |
| 		return -ENOMEM;
 | |
| 	}
 | |
| 
 | |
| 	fda->nr_alloc = nr_alloc;
 | |
| 	fda->entries  = entries;
 | |
| 	fda->priv     = priv;
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| struct fdarray *fdarray__new(int nr_alloc, int nr_autogrow)
 | |
| {
 | |
| 	struct fdarray *fda = calloc(1, sizeof(*fda));
 | |
| 
 | |
| 	if (fda != NULL) {
 | |
| 		if (fdarray__grow(fda, nr_alloc)) {
 | |
| 			free(fda);
 | |
| 			fda = NULL;
 | |
| 		} else {
 | |
| 			fda->nr_autogrow = nr_autogrow;
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	return fda;
 | |
| }
 | |
| 
 | |
| void fdarray__exit(struct fdarray *fda)
 | |
| {
 | |
| 	free(fda->entries);
 | |
| 	free(fda->priv);
 | |
| 	fdarray__init(fda, 0);
 | |
| }
 | |
| 
 | |
| void fdarray__delete(struct fdarray *fda)
 | |
| {
 | |
| 	fdarray__exit(fda);
 | |
| 	free(fda);
 | |
| }
 | |
| 
 | |
| int fdarray__add(struct fdarray *fda, int fd, short revents)
 | |
| {
 | |
| 	int pos = fda->nr;
 | |
| 
 | |
| 	if (fda->nr == fda->nr_alloc &&
 | |
| 	    fdarray__grow(fda, fda->nr_autogrow) < 0)
 | |
| 		return -ENOMEM;
 | |
| 
 | |
| 	fda->entries[fda->nr].fd     = fd;
 | |
| 	fda->entries[fda->nr].events = revents;
 | |
| 	fda->nr++;
 | |
| 	return pos;
 | |
| }
 | |
| 
 | |
| int fdarray__filter(struct fdarray *fda, short revents,
 | |
| 		    void (*entry_destructor)(struct fdarray *fda, int fd))
 | |
| {
 | |
| 	int fd, nr = 0;
 | |
| 
 | |
| 	if (fda->nr == 0)
 | |
| 		return 0;
 | |
| 
 | |
| 	for (fd = 0; fd < fda->nr; ++fd) {
 | |
| 		if (fda->entries[fd].revents & revents) {
 | |
| 			if (entry_destructor)
 | |
| 				entry_destructor(fda, fd);
 | |
| 
 | |
| 			continue;
 | |
| 		}
 | |
| 
 | |
| 		if (fd != nr) {
 | |
| 			fda->entries[nr] = fda->entries[fd];
 | |
| 			fda->priv[nr]	 = fda->priv[fd];
 | |
| 		}
 | |
| 
 | |
| 		++nr;
 | |
| 	}
 | |
| 
 | |
| 	return fda->nr = nr;
 | |
| }
 | |
| 
 | |
| int fdarray__poll(struct fdarray *fda, int timeout)
 | |
| {
 | |
| 	return poll(fda->entries, fda->nr, timeout);
 | |
| }
 | |
| 
 | |
| int fdarray__fprintf(struct fdarray *fda, FILE *fp)
 | |
| {
 | |
| 	int fd, printed = fprintf(fp, "%d [ ", fda->nr);
 | |
| 
 | |
| 	for (fd = 0; fd < fda->nr; ++fd)
 | |
| 		printed += fprintf(fp, "%s%d", fd ? ", " : "", fda->entries[fd].fd);
 | |
| 
 | |
| 	return printed + fprintf(fp, " ]");
 | |
| }
 |