ANDROID: task_mmu: add vendor hook for swap entry

Add vendor hook in smaps_pte_entry for swap entry
- android_vh_smaps_pte_entry
- android_vh_show_smap

This vendor hook is to show more information for
swap entries of a process based on the
characteristics, such as written-back, same-filled
or huge (uncompressed).

This also merges changes in
https://android-review.googlesource.com/c/kernel/common/+/3164628
to count and show swap_shared with single vendor hook.

Bug: 284059805

Change-Id: Ie4a48ae42212c056992d34a10b026b60439d0012
Signed-off-by: Sooyong Suk <s.suk@samsung.com>

drivers/android/vendor_hooks.c

@@ -273,3 +273,5 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_modify_scan_control);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_should_continue_reclaim);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_async_psi_bypass);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_cma_alloc_retry);
+EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_smaps_pte_entry);
+EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_show_smap);

fs/proc/task_mmu.c

@@ -23,6 +23,7 @@
 #include <linux/minmax.h>
 #include <linux/overflow.h>
 #include <linux/buildid.h>
+#include <trace/hooks/mm.h>
 
 #include <asm/elf.h>
 #include <asm/tlb.h>
@@ -658,6 +659,10 @@ struct mem_size_stats {
 	unsigned long shmem_thp;
 	unsigned long file_thp;
 	unsigned long swap;
+	unsigned long swap_shared;
+	unsigned long writeback;
+	unsigned long same;
+	unsigned long huge;
 	unsigned long shared_hugetlb;
 	unsigned long private_hugetlb;
 	unsigned long ksm;
@@ -820,6 +825,9 @@ static void smaps_pte_entry(pte_t *pte, unsigned long addr,
 			} else {
 				mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT;
 			}
+			trace_android_vh_smaps_pte_entry(swpent, mapcount,
+					&mss->swap_shared, &mss->writeback,
+					&mss->same, &mss->huge);
 		} else if (is_pfn_swap_entry(swpent)) {
 			if (is_device_private_entry(swpent))
 				present = true;
@@ -1133,6 +1141,8 @@ static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss,
 	SEQ_PUT_DEC(" kB\nLocked:         ",
 					mss->pss_locked >> PSS_SHIFT);
 	seq_puts(m, " kB\n");
+	trace_android_vh_show_smap(m, mss->swap_shared, mss->writeback,
+			mss->same, mss->huge);
 }
 
 static int show_smap(struct seq_file *m, void *v)

include/trace/hooks/mm.h

@@ -130,6 +130,16 @@ DECLARE_RESTRICTED_HOOK(android_rvh_vfree_bypass,
 DECLARE_HOOK(android_vh_cma_alloc_retry,
 	TP_PROTO(char *name, int *retry),
 	TP_ARGS(name, retry));
+DECLARE_HOOK(android_vh_smaps_pte_entry,
+	TP_PROTO(swp_entry_t entry, int mapcount,
+		unsigned long *swap_shared, unsigned long *writeback,
+		unsigned long *same, unsigned long *huge),
+	TP_ARGS(entry, mapcount, swap_shared, writeback, same, huge));
+DECLARE_HOOK(android_vh_show_smap,
+	TP_PROTO(struct seq_file *m,
+		unsigned long swap_shared, unsigned long writeback,
+		unsigned long same, unsigned long huge),
+	TP_ARGS(m, swap_shared, writeback, same, huge));
 #endif /* _TRACE_HOOK_MM_H */
 
 /* This part must be outside protection */