Em Tue, Oct 21, 2014 at 11:56:10AM -0700, Sukadev Bhattiprolu escreveu: > >From 773a3608a0cd2daf02e244cb9ffbf5bb6a0e724e Mon Sep 17 00:00:00 2001 > From: Sukadev Bhattiprolu <[email protected]> > Date: Tue, 21 Oct 2014 13:20:22 -0500 > Subject: [PATCH 1/1] perf/powerpc: Cache DWARF debug info
Jiri, isn't his related to that dsos caching thing you created? Anyway, there is a per machine struct (struct machine) where things like this should be put, please do not add globals or static variables in functions. - Arnaldo > Cache the DWARF debug info for DSO so we don't have to rebuild it for > each address in the DSO (duh!). > > $ time /tmp/perf.orig report -g > /tmp/report.1 > > real 0m1.845s > user 0m0.963s > sys 0m0.879s > > $ time /tmp/perf report -g > /tmp/report.2 > > real 0m0.089s > user 0m0.082s > sys 0m0.006s > > $ diff /tmp/report.1 /tmp/report.2 > $ > > Reported-by: Anton Blanchard <[email protected]> > Signed-off-by: Sukadev Bhattiprolu <[email protected]> > --- > tools/perf/arch/powerpc/util/skip-callchain-idx.c | 91 > ++++++++++++++++++++--- > 1 file changed, 82 insertions(+), 9 deletions(-) > > diff --git a/tools/perf/arch/powerpc/util/skip-callchain-idx.c > b/tools/perf/arch/powerpc/util/skip-callchain-idx.c > index d73ef8b..bfe254d 100644 > --- a/tools/perf/arch/powerpc/util/skip-callchain-idx.c > +++ b/tools/perf/arch/powerpc/util/skip-callchain-idx.c > @@ -38,6 +38,63 @@ static const Dwfl_Callbacks offline_callbacks = { > .section_address = dwfl_offline_section_address, > }; > > +struct list_head perf_dwfl_files; > + > +struct perf_dwfl_node { > + struct list_head node; > + char *exec_file; > + Dwfl *dwfl; > +}; > + > +static void perf_init_dwfl(void) > +{ > + static int dwfl_inited; > + > + if (!dwfl_inited) { > + dwfl_inited = 1; > + INIT_LIST_HEAD(&perf_dwfl_files); > + } > +} > + > +static Dwfl *perf_dwfl_find(const char *file_name) > +{ > + struct list_head *pos; > + struct perf_dwfl_node *node; > + > + perf_init_dwfl(); > + > + list_for_each(pos, &perf_dwfl_files) { > + node = list_entry(pos, struct perf_dwfl_node, node); > + if (!strcmp(node->exec_file, file_name)) > + return node->dwfl; > + } > + > + return NULL; > +} > + > + > +/* > + * Return 1 if were able to cache the DWARF debug info. 0 otherwise. > + */ > +static int perf_dwfl_cache(const char *file_name, Dwfl *dwfl) > +{ > + struct perf_dwfl_node *dwfl_node; > + > + dwfl_node = malloc(sizeof(struct perf_dwfl_node)); > + > + if (!dwfl_node) { > + pr_debug("%s(): Unable to alloc memory\n", __func__); > + return 0; > + } > + INIT_LIST_HEAD(&dwfl_node->node); > + dwfl_node->dwfl = dwfl; > + dwfl_node->exec_file = strdup(file_name); > + > + list_add(&dwfl_node->node, &perf_dwfl_files); > + > + return 1; > +} > + > > /* > * Use the DWARF expression for the Call-frame-address and determine > @@ -155,16 +212,26 @@ static int check_return_addr(const char *exec_file, > Dwarf_Addr pc) > Dwarf_Addr start = pc; > Dwarf_Addr end = pc; > bool signalp; > + int cached; > > - dwfl = dwfl_begin(&offline_callbacks); > + cached = 1; > + dwfl = perf_dwfl_find(exec_file); > if (!dwfl) { > - pr_debug("dwfl_begin() failed: %s\n", dwarf_errmsg(-1)); > - return -1; > - } > - > - if (dwfl_report_offline(dwfl, "", exec_file, -1) == NULL) { > - pr_debug("dwfl_report_offline() failed %s\n", dwarf_errmsg(-1)); > - goto out; > + dwfl = dwfl_begin(&offline_callbacks); > + if (!dwfl) { > + pr_debug("dwfl_begin() failed: %s\n", dwarf_errmsg(-1)); > + return -1; > + } > + > + if (dwfl_report_offline(dwfl, "", exec_file, -1) == NULL) { > + pr_debug("dwfl_report_offline() failed %s\n", > + dwarf_errmsg(-1)); > + goto out; > + } > + /* > + * If we fail to alloc memory, we lose the benefit of caching > + */ > + cached = perf_dwfl_cache(exec_file, dwfl); > } > > mod = dwfl_addrmodule(dwfl, pc); > @@ -194,7 +261,13 @@ static int check_return_addr(const char *exec_file, > Dwarf_Addr pc) > rc = check_return_reg(ra_regno, frame); > > out: > - dwfl_end(dwfl); > + /* > + * In the unlikely event that we were unable to cache the debug > + * info, release it so we don't leak fds. > + */ > + if (!cached) > + dwfl_end(dwfl); > + > return rc; > } > > -- > 1.8.4.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
