Commit 2171a925 authored by Arnaldo Carvalho de Melo's avatar Arnaldo Carvalho de Melo
Browse files

tools lib fd array: Allow associating an integer cookie with each entry 



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: default avatarArnaldo Carvalho de Melo <acme@redhat.com>

Link: http://lkml.kernel.org/n/tip-0p00bn83quck3fio3kcs9vca@git.kernel.org
parent 82396986

tools/lib/api/fd/array.c

+24 −4
Original line number Diff line number Diff line
@@ -13,21 +13,31 @@ 
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;

}
@@ -50,6 +60,7 @@ struct fdarray *fdarray__new(int nr_alloc, int nr_autogrow) 
void fdarray__exit(struct fdarray *fda)

{

	free(fda->entries);

	free(fda->priv);

	fdarray__init(fda, 0);

}
@@ -61,6 +72,8 @@ void fdarray__delete(struct fdarray *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;
@@ -68,10 +81,11 @@ int fdarray__add(struct fdarray *fda, int fd, short revents) 
	fda->entries[fda->nr].fd     = fd;

	fda->entries[fda->nr].events = revents;

	fda->nr++;

	return 0;

	return pos;

}



int fdarray__filter(struct fdarray *fda, short revents)

int fdarray__filter(struct fdarray *fda, short revents,

		    void (*entry_destructor)(struct fdarray *fda, int fd))

{

	int fd, nr = 0;
@@ -79,11 +93,17 @@ int fdarray__filter(struct fdarray *fda, short revents) 
		return 0;



	for (fd = 0; fd < fda->nr; ++fd) {

		if (fda->entries[fd].revents & revents)

		if (fda->entries[fd].revents & revents) {

			if (entry_destructor)

				entry_destructor(fda, fd);



			continue;

		}



		if (fd != nr)

		if (fd != nr) {

			fda->entries[nr] = fda->entries[fd];

			fda->priv[nr]	 = fda->priv[fd];

		}



		++nr;

	}

tools/lib/api/fd/array.h

+15 −1
Original line number Diff line number Diff line
@@ -5,11 +5,24 @@ 


struct pollfd;



/**

 * struct fdarray: Array of file descriptors

 *

 * @priv: Per array entry priv area, users should access just its contents,

 *	  not set it to anything, as it is kept in synch with @entries, being

 *	  realloc'ed, * for instance, in fdarray__{grow,filter}.

 *

 *	  I.e. using 'fda->priv[N].idx = * value' where N < fda->nr is ok,

 *	  but doing 'fda->priv = malloc(M)' is not allowed.

 */

struct fdarray {

	int	       nr;

	int	       nr_alloc;

	int	       nr_autogrow;

	struct pollfd *entries;

	union {

		int    idx;

	} *priv;

};



void fdarray__init(struct fdarray *fda, int nr_autogrow);
@@ -20,7 +33,8 @@ void fdarray__delete(struct fdarray *fda); 


int fdarray__add(struct fdarray *fda, int fd, short revents);

int fdarray__poll(struct fdarray *fda, int timeout);

int fdarray__filter(struct fdarray *fda, short revents);

int fdarray__filter(struct fdarray *fda, short revents,

		    void (*entry_destructor)(struct fdarray *fda, int fd));

int fdarray__grow(struct fdarray *fda, int extra);

int fdarray__fprintf(struct fdarray *fda, FILE *fp);

tools/perf/tests/fdarray.c

+4 −4
Original line number Diff line number Diff line
@@ -36,7 +36,7 @@ int test__fdarray__filter(void) 
	}



	fdarray__init_revents(fda, POLLIN);

	nr_fds = fdarray__filter(fda, POLLHUP);

	nr_fds = fdarray__filter(fda, POLLHUP, NULL);

	if (nr_fds != fda->nr_alloc) {

		pr_debug("\nfdarray__filter()=%d != %d shouldn't have filtered anything",

			 nr_fds, fda->nr_alloc);
@@ -44,7 +44,7 @@ int test__fdarray__filter(void) 
	}



	fdarray__init_revents(fda, POLLHUP);

	nr_fds = fdarray__filter(fda, POLLHUP);

	nr_fds = fdarray__filter(fda, POLLHUP, NULL);

	if (nr_fds != 0) {

		pr_debug("\nfdarray__filter()=%d != %d, should have filtered all fds",

			 nr_fds, fda->nr_alloc);
@@ -57,7 +57,7 @@ int test__fdarray__filter(void) 


	pr_debug("\nfiltering all but fda->entries[2]:");

	fdarray__fprintf_prefix(fda, "before", stderr);

	nr_fds = fdarray__filter(fda, POLLHUP);

	nr_fds = fdarray__filter(fda, POLLHUP, NULL);

	fdarray__fprintf_prefix(fda, " after", stderr);

	if (nr_fds != 1) {

		pr_debug("\nfdarray__filter()=%d != 1, should have left just one event", nr_fds);
@@ -78,7 +78,7 @@ int test__fdarray__filter(void) 


	pr_debug("\nfiltering all but (fda->entries[0], fda->entries[3]):");

	fdarray__fprintf_prefix(fda, "before", stderr);

	nr_fds = fdarray__filter(fda, POLLHUP);

	nr_fds = fdarray__filter(fda, POLLHUP, NULL);

	fdarray__fprintf_prefix(fda, " after", stderr);

	if (nr_fds != 2) {

		pr_debug("\nfdarray__filter()=%d != 2, should have left just two events",

tools/perf/util/evlist.c

+1 −1
Original line number Diff line number Diff line
@@ -435,7 +435,7 @@ int perf_evlist__add_pollfd(struct perf_evlist *evlist, int fd) 


int perf_evlist__filter_pollfd(struct perf_evlist *evlist, short revents_and_mask)

{

	return fdarray__filter(&evlist->pollfd, revents_and_mask);

	return fdarray__filter(&evlist->pollfd, revents_and_mask, NULL);

}



int perf_evlist__poll(struct perf_evlist *evlist, int timeout)

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