[PATCH] buffermem counter tweaks in proc

[Chris Mason]

Hello everyone,

A few people have seen free report bogus numbers for the number of used
buffers in the output of free.

Andrea pointed out this was probably because we now increment 
both buffermem_pages and page_cache_size when getblk triggers 
a page allocation.

This patch tweaks /proc/meminfo to deal take that into account:

-chris

--- l-2.4.12/fs/proc/proc_misc.c Sun, 23 Sep 2001 20:11:16 -0400 
+++ l-2.4.12/fs/proc/proc_misc.c Wed, 10 Oct 2001 13:12:26 -0400 
@@ -140,6 +140,7 @@
 {
 	struct sysinfo i;
 	int len;
+	int pg_size ;
 
 /*
  * display in kilobytes.
@@ -148,12 +149,14 @@
 #define B(x) ((unsigned long long)(x) << PAGE_SHIFT)
 	si_meminfo(&i);
 	si_swapinfo(&i);
+	pg_size = atomic_read(&page_cache_size) - i.bufferram ;
+
 	len = sprintf(page, "        total:    used:    free:  shared: buffers:  cached:\n"
 		"Mem:  %8Lu %8Lu %8Lu %8Lu %8Lu %8Lu\n"
 		"Swap: %8Lu %8Lu %8Lu\n",
 		B(i.totalram), B(i.totalram-i.freeram), B(i.freeram),
 		B(i.sharedram), B(i.bufferram),
-		B(atomic_read(&page_cache_size)), B(i.totalswap),
+		B(pg_size), B(i.totalswap),
 		B(i.totalswap-i.freeswap), B(i.freeswap));
 	/*
 	 * Tagged format, for easy grepping and expansion.
@@ -179,7 +182,7 @@
 		K(i.freeram),
 		K(i.sharedram),
 		K(i.bufferram),
-		K(atomic_read(&page_cache_size) - swapper_space.nrpages),
+		K(pg_size - swapper_space.nrpages),
 		K(swapper_space.nrpages),
 		K(nr_active_pages),
 		K(nr_inactive_pages),