perf evlist: Handle default value for 'pages' on mmap method

Every tool that calls this and allows the user to override the value
needs this logic.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-lwscxpg57xfzahz5dmdfp9uz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 4799195..749862d 100644 (file)
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -456,10 +456,6 @@ static int __cmd_record(int argc, const char **argv)
        perf_header__set_feat(&session->header, HEADER_NUMA_TOPOLOGY);
        perf_header__set_feat(&session->header, HEADER_CPUID);
 
-       /* 512 kiB: default amount of unprivileged mlocked memory */
-       if (mmap_pages == UINT_MAX)
-               mmap_pages = (512 * 1024) / page_size;
-
        if (forks) {
                err = perf_evlist__prepare_workload(evsel_list, &record_opts, argv);
                if (err < 0) {

diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index a472247..81237dc 100644 (file)
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -507,14 +507,20 @@ out_unmap:
  *
  * Using perf_evlist__read_on_cpu does this automatically.
  */
-int perf_evlist__mmap(struct perf_evlist *evlist, int pages, bool overwrite)
+int perf_evlist__mmap(struct perf_evlist *evlist, unsigned int pages,
+                     bool overwrite)
 {
        unsigned int page_size = sysconf(_SC_PAGE_SIZE);
-       int mask = pages * page_size - 1;
        struct perf_evsel *evsel;
        const struct cpu_map *cpus = evlist->cpus;
        const struct thread_map *threads = evlist->threads;
-       int prot = PROT_READ | (overwrite ? 0 : PROT_WRITE);
+       int prot = PROT_READ | (overwrite ? 0 : PROT_WRITE), mask;
+
+        /* 512 kiB: default amount of unprivileged mlocked memory */
+        if (pages == UINT_MAX)
+                pages = (512 * 1024) / page_size;
+
+       mask = pages * page_size - 1;
 
        if (evlist->mmap == NULL && perf_evlist__alloc_mmap(evlist) < 0)
                return -ENOMEM;

diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
index 07d56b3..17e9c80 100644 (file)
--- a/tools/perf/util/evlist.h
+++ b/tools/perf/util/evlist.h
@@ -79,7 +79,8 @@ int perf_evlist__prepare_workload(struct perf_evlist *evlist,
 int perf_evlist__start_workload(struct perf_evlist *evlist);
 
 int perf_evlist__alloc_mmap(struct perf_evlist *evlist);
-int perf_evlist__mmap(struct perf_evlist *evlist, int pages, bool overwrite);
+int perf_evlist__mmap(struct perf_evlist *evlist, unsigned int pages,
+                     bool overwrite);
 void perf_evlist__munmap(struct perf_evlist *evlist);
 
 void perf_evlist__disable(struct perf_evlist *evlist);