percpu: generalize first chunk allocator selection
Now that all first chunk allocators are in mm/percpu.c, it makes sense
to make generalize percpu_alloc kernel parameter. Define PCPU_FC_*
and set pcpu_chosen_fc using early_param() in mm/percpu.c. Arch code
can use the set value to determine which first chunk allocator to use.
Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/mm/percpu.c b/mm/percpu.c
index 7971997..7fb40bb 100644
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -1414,6 +1414,38 @@
return pcpu_unit_size;
}
+const char *pcpu_fc_names[PCPU_FC_NR] __initdata = {
+ [PCPU_FC_AUTO] = "auto",
+ [PCPU_FC_EMBED] = "embed",
+ [PCPU_FC_PAGE] = "page",
+ [PCPU_FC_LPAGE] = "lpage",
+};
+
+enum pcpu_fc pcpu_chosen_fc __initdata = PCPU_FC_AUTO;
+
+static int __init percpu_alloc_setup(char *str)
+{
+ if (0)
+ /* nada */;
+#ifdef CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK
+ else if (!strcmp(str, "embed"))
+ pcpu_chosen_fc = PCPU_FC_EMBED;
+#endif
+#ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
+ else if (!strcmp(str, "page"))
+ pcpu_chosen_fc = PCPU_FC_PAGE;
+#endif
+#ifdef CONFIG_NEED_PER_CPU_LPAGE_FIRST_CHUNK
+ else if (!strcmp(str, "lpage"))
+ pcpu_chosen_fc = PCPU_FC_LPAGE;
+#endif
+ else
+ pr_warning("PERCPU: unknown allocator %s specified\n", str);
+
+ return 0;
+}
+early_param("percpu_alloc", percpu_alloc_setup);
+
static inline size_t pcpu_calc_fc_sizes(size_t static_size,
size_t reserved_size,
ssize_t *dyn_sizep)
