diff options
| author | Markus Metzger <markus.t.metzger@intel.com> | 2013-04-10 13:43:41 +0200 |
|---|---|---|
| committer | Markus Metzger <markus.t.metzger@intel.com> | 2014-01-16 12:58:53 +0100 |
| commit | d0fa75352b7ffd586499d28983bff5d714e5211a (patch) | |
| tree | 29c8cc4dc40b9d008dcc9754c2781e11d99a9c7c /gdb | |
| parent | 5de9129b066591c6ef57829ab9e1c2a030de49af (diff) | |
| download | gdb-d0fa75352b7ffd586499d28983bff5d714e5211a.zip gdb-d0fa75352b7ffd586499d28983bff5d714e5211a.tar.gz gdb-d0fa75352b7ffd586499d28983bff5d714e5211a.tar.bz2 | |
btrace: increase buffer size
Try to allocate as much buffer as we can for each thread with a maximum
of 64KB.
2014-01-16 Markus Metzger <markus.t.metzger@intel.com>
* common/linux-btrace.c (linux_enable_btrace): Enlarge buffer.
Diffstat (limited to 'gdb')
| -rw-r--r-- | gdb/ChangeLog | 4 | ||||
| -rw-r--r-- | gdb/common/linux-btrace.c | 25 |
2 files changed, 19 insertions, 10 deletions
diff --git a/gdb/ChangeLog b/gdb/ChangeLog index acd6b02..50c6bcd 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,5 +1,9 @@ 2014-01-16 Markus Metzger <markus.t.metzger@intel.com> + * common/linux-btrace.c (linux_enable_btrace): Enlarge buffer. + +2014-01-16 Markus Metzger <markus.t.metzger@intel.com> + * btrace.c (ftrace_new_function): Start counting at one. * record-btrace.c (record_btrace_info): Adjust number of calls and insns. diff --git a/gdb/common/linux-btrace.c b/gdb/common/linux-btrace.c index 5474049..e469900 100644 --- a/gdb/common/linux-btrace.c +++ b/gdb/common/linux-btrace.c @@ -423,7 +423,7 @@ struct btrace_target_info * linux_enable_btrace (ptid_t ptid) { struct btrace_target_info *tinfo; - int pid; + int pid, pg; tinfo = xzalloc (sizeof (*tinfo)); tinfo->ptid = ptid; @@ -451,17 +451,22 @@ linux_enable_btrace (ptid_t ptid) if (tinfo->file < 0) goto err; - /* We hard-code the trace buffer size. - At some later time, we should make this configurable. */ - tinfo->size = 1; - tinfo->buffer = mmap (NULL, perf_event_mmap_size (tinfo), - PROT_READ, MAP_SHARED, tinfo->file, 0); - if (tinfo->buffer == MAP_FAILED) - goto err_file; + /* We try to allocate as much buffer as we can get. + We could allow the user to specify the size of the buffer, but then + we'd leave this search for the maximum buffer size to him. */ + for (pg = 4; pg >= 0; --pg) + { + /* The number of pages we request needs to be a power of two. */ + tinfo->size = 1 << pg; + tinfo->buffer = mmap (NULL, perf_event_mmap_size (tinfo), + PROT_READ, MAP_SHARED, tinfo->file, 0); + if (tinfo->buffer == MAP_FAILED) + continue; - return tinfo; + return tinfo; + } - err_file: + /* We were not able to allocate any buffer. */ close (tinfo->file); err: |