diff options
Diffstat (limited to 'cachegrind')
| -rw-r--r-- | cachegrind/cg_main.c | 17 | ||||
| -rw-r--r-- | cachegrind/docs/cg-manual.xml | 13 |
2 files changed, 23 insertions, 7 deletions
diff --git a/cachegrind/cg_main.c b/cachegrind/cg_main.c index dcfa79c0..bd683255 100644 --- a/cachegrind/cg_main.c +++ b/cachegrind/cg_main.c @@ -1256,9 +1256,6 @@ static CacheCC Dw_total; static BranchCC Bc_total; static BranchCC Bi_total; -// The output file name. Controlled by --cachegrind-out-file. -static Char* cachegrind_out_file = NULL; - static void fprint_CC_table_and_calc_totals(void) { Int i, fd; @@ -1266,6 +1263,14 @@ static void fprint_CC_table_and_calc_totals(void) Char buf[512], *currFile = NULL, *currFn = NULL; LineCC* lineCC; + // Setup output filename. Nb: it's important to do this now, ie. as late + // as possible. If we do it at start-up and the program forks and the + // output file format string contains a %p (pid) specifier, both the + // parent and child will incorrectly write to the same file; this + // happened in 3.3.0. + Char* cachegrind_out_file = + VG_(expand_file_name)("--cachegrind-out-file", clo_cachegrind_out_file); + sres = VG_(open)(cachegrind_out_file, VKI_O_CREAT|VKI_O_TRUNC|VKI_O_WRONLY, VKI_S_IRUSR|VKI_S_IWUSR); if (sres.isError) { @@ -1276,9 +1281,11 @@ static void fprint_CC_table_and_calc_totals(void) cachegrind_out_file ); VG_(message)(Vg_UserMsg, " ... so simulation results will be missing."); + VG_(free)(cachegrind_out_file); return; } else { fd = sres.res; + VG_(free)(cachegrind_out_file); } // "desc:" lines (giving I1/D1/L2 cache configuration). The spaces after @@ -1752,10 +1759,6 @@ static void cg_post_clo_init(void) VG_(exit)(2); } - // Setup output filename. - cachegrind_out_file = - VG_(expand_file_name)("--cachegrind-out-file", clo_cachegrind_out_file); - CC_table = VG_(OSetGen_Create)(offsetof(LineCC, loc), cmp_CodeLoc_LineCC, diff --git a/cachegrind/docs/cg-manual.xml b/cachegrind/docs/cg-manual.xml index 30857fa9..7c1764e0 100644 --- a/cachegrind/docs/cg-manual.xml +++ b/cachegrind/docs/cg-manual.xml @@ -820,6 +820,19 @@ way as for C/C++ programs.</para> </sect2> +<sect2 id="ms-manual.forkingprograms" xreflabel="Forking Programs"> +<title>Forking Programs</title> +<para>If your program forks, the child will inherit all the profiling data that +has been gathered for the parent.</para> + +<para>If the output file format string (controlled by +<option>--cachegrind-out-file</option>) does not contain <option>%p</option>, +then the outputs from the parent and child will be intermingled in a single +output file, which will almost certainly make it unreadable by +cg_annotate.</para> +</sect2> + + </sect1> |