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>

diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 9c806ab..752577f 100644 (file)
--- 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;