perf session: Move all state items to reader object

We need all the state info about reader in separate object to load data
from multiple files, so we can keep multiple readers at the same time.
Moving all items that need to be kept from reader__process_events to
the reader object. Introducing mmap_cur to keep current mapping.

Suggested-by: Jiri Olsa <[email protected]>
Reviewed-by: Jiri Olsa <[email protected]>
Reviewed-by: Riccardo Mancini <[email protected]>
Signed-off-by: Alexey Bayduraev <[email protected]>
Tested-by: Riccardo Mancini <[email protected]>
Acked-by: Namhyung Kim <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Antonov <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Alexei Budankov <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: https://lore.kernel.org/r/5c7bdebfaadd7fcb729bd999b181feccaa292e8e.1634113027.git.alexey.v.bayduraev@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

1 files changed, 35 insertions, 28 deletions

diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index bdf1da9ea418..f927bcd39b0a 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -2176,6 +2176,13 @@ struct reader {
 	u64		 data_offset;
 	reader_cb_t	 process;
 	bool		 in_place_update;
+	char		 *mmaps[NUM_MMAPS];
+	size_t		 mmap_size;
+	int		 mmap_idx;
+	char		 *mmap_cur;
+	u64		 file_pos;
+	u64		 file_offset;
+	u64		 head;
 };
 
 static int
@@ -2183,28 +2190,27 @@ reader__process_events(struct reader *rd, struct perf_session *session,
 		       struct ui_progress *prog)
 {
 	u64 data_size = rd->data_size;
-	u64 head, page_offset, file_offset, file_pos, size;
-	int err = 0, mmap_prot, mmap_flags, map_idx = 0;
-	size_t	mmap_size;
-	char *buf, *mmaps[NUM_MMAPS];
+	u64 page_offset, size;
+	int err = 0, mmap_prot, mmap_flags;
+	char *buf, **mmaps = rd->mmaps;
 	union perf_event *event;
 	s64 skip;
 
 	page_offset = page_size * (rd->data_offset / page_size);
-	file_offset = page_offset;
-	head = rd->data_offset - page_offset;
+	rd->file_offset = page_offset;
+	rd->head = rd->data_offset - page_offset;
 
 	ui_progress__init_size(prog, data_size, "Processing events...");
 
 	data_size += rd->data_offset;
 
-	mmap_size = MMAP_SIZE;
-	if (mmap_size > data_size) {
-		mmap_size = data_size;
+	rd->mmap_size = MMAP_SIZE;
+	if (rd->mmap_size > data_size) {
+		rd->mmap_size = data_size;
 		session->one_mmap = true;
 	}
 
-	memset(mmaps, 0, sizeof(mmaps));
+	memset(mmaps, 0, sizeof(rd->mmaps));
 
 	mmap_prot  = PROT_READ;
 	mmap_flags = MAP_SHARED;
@@ -2216,35 +2222,36 @@ reader__process_events(struct reader *rd, struct perf_session *session,
 		mmap_flags = MAP_PRIVATE;
 	}
 remap:
-	buf = mmap(NULL, mmap_size, mmap_prot, mmap_flags, rd->fd,
-		   file_offset);
+	buf = mmap(NULL, rd->mmap_size, mmap_prot, mmap_flags, rd->fd,
+		   rd->file_offset);
 	if (buf == MAP_FAILED) {
 		pr_err("failed to mmap file\n");
 		err = -errno;
 		goto out;
 	}
-	mmaps[map_idx] = buf;
-	map_idx = (map_idx + 1) & (ARRAY_SIZE(mmaps) - 1);
-	file_pos = file_offset + head;
+	mmaps[rd->mmap_idx] = rd->mmap_cur = buf;
+	rd->mmap_idx = (rd->mmap_idx + 1) & (ARRAY_SIZE(rd->mmaps) - 1);
+	rd->file_pos = rd->file_offset + rd->head;
 	if (session->one_mmap) {
 		session->one_mmap_addr = buf;
-		session->one_mmap_offset = file_offset;
+		session->one_mmap_offset = rd->file_offset;
 	}
 
 more:
-	event = fetch_mmaped_event(head, mmap_size, buf, session->header.needs_swap);
+	event = fetch_mmaped_event(rd->head, rd->mmap_size, rd->mmap_cur,
+				   session->header.needs_swap);
 	if (IS_ERR(event))
 		return PTR_ERR(event);
 
 	if (!event) {
-		if (mmaps[map_idx]) {
-			munmap(mmaps[map_idx], mmap_size);
-			mmaps[map_idx] = NULL;
+		if (mmaps[rd->mmap_idx]) {
+			munmap(mmaps[rd->mmap_idx], rd->mmap_size);
+			mmaps[rd->mmap_idx] = NULL;
 		}
 
-		page_offset = page_size * (head / page_size);
-		file_offset += page_offset;
-		head -= page_offset;
+		page_offset = page_size * (rd->head / page_size);
+		rd->file_offset += page_offset;
+		rd->head -= page_offset;
 		goto remap;
 	}
 
@@ -2253,9 +2260,9 @@ more:
 	skip = -EINVAL;
 
 	if (size < sizeof(struct perf_event_header) ||
-	    (skip = rd->process(session, event, file_pos)) < 0) {
+	    (skip = rd->process(session, event, rd->file_pos)) < 0) {
 		pr_err("%#" PRIx64 " [%#x]: failed to process type: %d [%s]\n",
-		       file_offset + head, event->header.size,
+		       rd->file_offset + rd->head, event->header.size,
 		       event->header.type, strerror(-skip));
 		err = skip;
 		goto out;
@@ -2264,8 +2271,8 @@ more:
 	if (skip)
 		size += skip;
 
-	head += size;
-	file_pos += size;
+	rd->head += size;
+	rd->file_pos += size;
 
 	err = __perf_session__process_decomp_events(session);
 	if (err)
@@ -2276,7 +2283,7 @@ more:
 	if (session_done())
 		goto out;
 
-	if (file_pos < data_size)
+	if (rd->file_pos < data_size)
 		goto more;
 
 out: