perf session: Use sensible mmap size

On 64bit we can map the whole file in one go, on 32bit we can at least map
32MB and not map/unmap tiny chunks of the file.

Base the progress bar on 1/16 of the data size.

Preparatory patch to get rid of the malloc/memcpy/free of trace data.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20101130163820.213687773@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 29 insertions, 12 deletions

diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 9c806ab565ea..752577fdb16e 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -101,7 +101,15 @@ struct perf_session *perf_session__new(const char *filename, int mode, bool forc
         INIT_LIST_HEAD(&self->dead_threads);
         self->hists_tree = RB_ROOT;
         self->last_match = NULL;
-        self->mmap_window = 32;
+        /*
+         * On 64bit we can mmap the data file in one go. No need for tiny mmap
+         * slices. On 32bit we use 32MB.
+         */
+#if BITS_PER_LONG == 64
+        self->mmap_window = ULLONG_MAX;
+#else
+        self->mmap_window = 32 * 1024 * 1024ULL;
+#endif
         self->machines = RB_ROOT;
         self->repipe = repipe;
         INIT_LIST_HEAD(&self->ordered_samples.samples);
@@ -738,18 +746,14 @@ int __perf_session__process_events(struct perf_session *session,
                                    u64 data_offset, u64 data_size,
                                    u64 file_size, struct perf_event_ops *ops)
 {
-        u64 head, page_offset, file_offset, file_pos;
+        u64 head, page_offset, file_offset, file_pos, progress_next;
         int err, mmap_prot, mmap_flags;
         struct ui_progress *progress;
-        size_t  page_size;
+        size_t  page_size, mmap_size;
         event_t *event;
         uint32_t size;
         char *buf;
 
-        progress = ui_progress__new("Processing events...", session->size);
-        if (progress == NULL)
-                return -1;
-
         perf_event_ops__fill_defaults(ops);
 
         page_size = sysconf(_SC_PAGESIZE);
@@ -761,6 +765,15 @@ int __perf_session__process_events(struct perf_session *session,
         if (data_offset + data_size < file_size)
                 file_size = data_offset + data_size;
 
+        progress_next = file_size / 16;
+        progress = ui_progress__new("Processing events...", file_size);
+        if (progress == NULL)
+                return -1;
+
+        mmap_size = session->mmap_window;
+        if (mmap_size > file_size)
+                mmap_size = file_size;
+
         mmap_prot  = PROT_READ;
         mmap_flags = MAP_SHARED;
 
@@ -769,15 +782,14 @@ int __perf_session__process_events(struct perf_session *session,
                 mmap_flags = MAP_PRIVATE;
         }
 remap:
-        buf = mmap(NULL, page_size * session->mmap_window, mmap_prot,
-                   mmap_flags, session->fd, file_offset);
+        buf = mmap(NULL, mmap_size, mmap_prot, mmap_flags, session->fd,
+                   file_offset);
         if (buf == MAP_FAILED) {
                 pr_err("failed to mmap file\n");
                 err = -errno;
                 goto out_err;
         }
         file_pos = file_offset + head;
-        ui_progress__update(progress, file_offset);
 
 more:
         event = (event_t *)(buf + head);
@@ -788,10 +800,10 @@ more:
         if (size == 0)
                 size = 8;
 
-        if (head + event->header.size >= page_size * session->mmap_window) {
+        if (head + event->header.size >= mmap_size) {
                 int munmap_ret;
 
-                munmap_ret = munmap(buf, page_size * session->mmap_window);
+                munmap_ret = munmap(buf, mmap_size);
                 assert(munmap_ret == 0);
 
                 page_offset = page_size * (head / page_size);
@@ -823,6 +835,11 @@ more:
         head += size;
         file_pos += size;
 
+        if (file_pos >= progress_next) {
+                progress_next += file_size / 16;
+                ui_progress__update(progress, file_pos);
+        }
+
         if (file_pos < file_size)
                 goto more;