ANDROID: mm: add a hook to amend /proc/pagetypeinfo output

print the Customized page info when /proc/pagetypeinfo is read

Bug: 391128435

Change-Id: I6f64c3eaef5d9aad0a73dffd8914937bc57eb5af
Signed-off-by: yipeng xiang <yipengxiang@honor.corp-partner.google.com>

drivers/android/vendor_hooks.c

@@ -163,6 +163,7 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_is_fpsimd_save);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_process_madvise_begin);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_process_madvise_iter);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_sched_show_task);
+EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_pagetypeinfo_show);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_check_uninterruptible_tasks);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_check_uninterruptible_tasks_dn);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_ftrace_oops_enter);

include/trace/hooks/mm.h

@@ -50,6 +50,9 @@ DECLARE_HOOK(android_vh_io_statistics,
 	TP_PROTO(struct address_space *mapping, unsigned int index,
 		unsigned int nr_page, bool read, bool direct),
 	TP_ARGS(mapping, index, nr_page, read, direct));
+DECLARE_HOOK(android_vh_pagetypeinfo_show,
+	TP_PROTO(struct seq_file *m),
+	TP_ARGS(m));
 
 struct cma;
 DECLARE_HOOK(android_vh_cma_alloc_bypass,

mm/vmstat.c

@@ -29,6 +29,7 @@
 #include <linux/page_owner.h>
 #include <linux/sched/isolation.h>
 
+#include <trace/hooks/mm.h>
 #include "internal.h"
 
 #ifdef CONFIG_NUMA
@@ -1690,6 +1691,7 @@ static int pagetypeinfo_show(struct seq_file *m, void *arg)
 	pagetypeinfo_showfree(m, pgdat);
 	pagetypeinfo_showblockcount(m, pgdat);
 	pagetypeinfo_showmixedcount(m, pgdat);
+	trace_android_vh_pagetypeinfo_show(m);
 
 	return 0;
 }