diff --git a/Documentation/printk-formats.txt b/Documentation/printk-formats.txt
index 5d1128bf02824aaf2e16ef332e7cef014cccf7b6..5962949944fd7307530f26c54c65d783745a8a27 100644
--- a/Documentation/printk-formats.txt
+++ b/Documentation/printk-formats.txt
@@ -298,6 +298,24 @@ bitmap and its derivatives such as cpumask and nodemask:
Passed by reference.
+Flags bitfields such as page flags, gfp_flags:
+
+ %pGp referenced|uptodate|lru|active|private
+ %pGg GFP_USER|GFP_DMA32|GFP_NOWARN
+ %pGv read|exec|mayread|maywrite|mayexec|denywrite
+
+ For printing flags bitfields as a collection of symbolic constants that
+ would construct the value. The type of flags is given by the third
+ character. Currently supported are [p]age flags, [v]ma_flags (both
+ expect unsigned long *) and [g]fp_flags (expects gfp_t *). The flag
+ names and print order depends on the particular type.
+
+ Note that this format should not be used directly in TP_printk() part
+ of a tracepoint. Instead, use the show_*_flags() functions from
+ <trace/events/mmflags.h>.
+
+ Passed by reference.
+
Network device features:
%pNF 0x000000000000c000
diff --git a/lib/test_printf.c b/lib/test_printf.c
index 4f6ae60433bc5d1e1d6df9b7c8d5d359512ad82a..563f10e6876aecf6e3932e0a2e955305f271b249 100644
--- a/lib/test_printf.c
+++ b/lib/test_printf.c
@@ -17,6 +17,9 @@
#include <linux/socket.h>
#include <linux/in.h>
+#include <linux/gfp.h>
+#include <linux/mm.h>
+
#define BUF_SIZE 256
#define PAD_SIZE 16
#define FILL_CHAR '$'
@@ -410,6 +413,55 @@ netdev_features(void)
{
}
+static void __init
+flags(void)
+{
+ unsigned long flags;
+ gfp_t gfp;
+ char *cmp_buffer;
+
+ flags = 0;
+ test("", "%pGp", &flags);
+
+ /* Page flags should filter the zone id */
+ flags = 1UL << NR_PAGEFLAGS;
+ test("", "%pGp", &flags);
+
+ flags |= 1UL << PG_uptodate | 1UL << PG_dirty | 1UL << PG_lru
+ | 1UL << PG_active | 1UL << PG_swapbacked;
+ test("uptodate|dirty|lru|active|swapbacked", "%pGp", &flags);
+
+
+ flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC
+ | VM_DENYWRITE;
+ test("read|exec|mayread|maywrite|mayexec|denywrite", "%pGv", &flags);
+
+ gfp = GFP_TRANSHUGE;
+ test("GFP_TRANSHUGE", "%pGg", &gfp);
+
+ gfp = GFP_ATOMIC|__GFP_DMA;
+ test("GFP_ATOMIC|GFP_DMA", "%pGg", &gfp);
+
+ gfp = __GFP_ATOMIC;
+ test("__GFP_ATOMIC", "%pGg", &gfp);
+
+ cmp_buffer = kmalloc(BUF_SIZE, GFP_KERNEL);
+ if (!cmp_buffer)
+ return;
+
+ /* Any flags not translated by the table should remain numeric */
+ gfp = ~__GFP_BITS_MASK;
+ snprintf(cmp_buffer, BUF_SIZE, "%#lx", (unsigned long) gfp);
+ test(cmp_buffer, "%pGg", &gfp);
+
+ snprintf(cmp_buffer, BUF_SIZE, "__GFP_ATOMIC|%#lx",
+ (unsigned long) gfp);
+ gfp |= __GFP_ATOMIC;
+ test(cmp_buffer, "%pGg", &gfp);
+
+ kfree(cmp_buffer);
+}
+
static void __init
test_pointer(void)
{
@@ -428,6 +480,7 @@ test_pointer(void)
struct_clk();
bitmap();
netdev_features();
+ flags();
}
static int __init
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index f44e178e6edec22e2f7c405f8cb433b2be935f83..525c8e19bda2b8a4e7398d7fc19064b2abc84b45 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -35,6 +35,8 @@
#include <linux/blkdev.h>
#endif
+#include "../mm/internal.h" /* For the trace_print_flags arrays */
+
#include <asm/page.h> /* for PAGE_SIZE */
#include <asm/sections.h> /* for dereference_function_descriptor() */
#include <asm/byteorder.h> /* cpu_to_le16 */
@@ -1407,6 +1409,72 @@ char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
}
}
+static
+char *format_flags(char *buf, char *end, unsigned long flags,
+ const struct trace_print_flags *names)
+{
+ unsigned long mask;
+ const struct printf_spec strspec = {
+ .field_width = -1,
+ .precision = -1,
+ };
+ const struct printf_spec numspec = {
+ .flags = SPECIAL|SMALL,
+ .field_width = -1,
+ .precision = -1,
+ .base = 16,
+ };
+
+ for ( ; flags && names->name; names++) {
+ mask = names->mask;
+ if ((flags & mask) != mask)
+ continue;
+
+ buf = string(buf, end, names->name, strspec);
+
+ flags &= ~mask;
+ if (flags) {
+ if (buf < end)
+ *buf = '|';
+ buf++;
+ }
+ }
+
+ if (flags)
+ buf = number(buf, end, flags, numspec);
+
+ return buf;
+}
+
+static noinline_for_stack
+char *flags_string(char *buf, char *end, void *flags_ptr, const char *fmt)
+{
+ unsigned long flags;
+ const struct trace_print_flags *names;
+
+ switch (fmt[1]) {
+ case 'p':
+ flags = *(unsigned long *)flags_ptr;
+ /* Remove zone id */
+ flags &= (1UL << NR_PAGEFLAGS) - 1;
+ names = pageflag_names;
+ break;
+ case 'v':
+ flags = *(unsigned long *)flags_ptr;
+ names = vmaflag_names;
+ break;
+ case 'g':
+ flags = *(gfp_t *)flags_ptr;
+ names = gfpflag_names;
+ break;
+ default:
+ WARN_ONCE(1, "Unsupported flags modifier: %c\n", fmt[1]);
+ return buf;
+ }
+
+ return format_flags(buf, end, flags, names);
+}
+
int kptr_restrict __read_mostly;
/*
@@ -1495,6 +1563,11 @@ int kptr_restrict __read_mostly;
* - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
* (legacy clock framework) of the clock
* - 'Cr' For a clock, it prints the current rate of the clock
+ * - 'G' For flags to be printed as a collection of symbolic strings that would
+ * construct the specific value. Supported flags given by option:
+ * p page flags (see struct page) given as pointer to unsigned long
+ * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t
+ * v vma flags (VM_*) given as pointer to unsigned long
*
* ** Please update also Documentation/printk-formats.txt when making changes **
*
@@ -1648,6 +1721,8 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr,
return bdev_name(buf, end, ptr, spec, fmt);
#endif
+ case 'G':
+ return flags_string(buf, end, ptr, fmt);
}
spec.flags |= SMALL;
if (spec.field_width == -1) {
diff --git a/mm/debug.c b/mm/debug.c
index 410af904a7d513a5fae5424458dcd70e39ce9e05..0328fd3775451670d5e454ed69b2548b184794d2 100644
--- a/mm/debug.c
+++ b/mm/debug.c
@@ -11,12 +11,21 @@
#include <linux/memcontrol.h>
#include <trace/events/mmflags.h>
-static const struct trace_print_flags pageflag_names[] = {
- __def_pageflag_names
+#include "internal.h"
+
+const struct trace_print_flags pageflag_names[] = {
+ __def_pageflag_names,
+ {0, NULL}
+};
+
+const struct trace_print_flags gfpflag_names[] = {
+ __def_gfpflag_names,
+ {0, NULL}
};
-static const struct trace_print_flags gfpflag_names[] = {
- __def_gfpflag_names
+const struct trace_print_flags vmaflag_names[] = {
+ __def_vmaflag_names,
+ {0, NULL}
};
static void dump_flags(unsigned long flags,
@@ -58,14 +67,15 @@ void dump_page_badflags(struct page *page, const char *reason,
if (PageCompound(page))
pr_cont(" compound_mapcount: %d", compound_mapcount(page));
pr_cont("\n");
- BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) != __NR_PAGEFLAGS);
- dump_flags(page->flags, pageflag_names, ARRAY_SIZE(pageflag_names));
+ BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) != __NR_PAGEFLAGS + 1);
+ dump_flags(page->flags, pageflag_names,
+ ARRAY_SIZE(pageflag_names) - 1);
if (reason)
pr_alert("page dumped because: %s\n", reason);
if (page->flags & badflags) {
pr_alert("bad because of flags:\n");
- dump_flags(page->flags & badflags,
- pageflag_names, ARRAY_SIZE(pageflag_names));
+ dump_flags(page->flags & badflags, pageflag_names,
+ ARRAY_SIZE(pageflag_names) - 1);
}
#ifdef CONFIG_MEMCG
if (page->mem_cgroup)
@@ -81,10 +91,6 @@ EXPORT_SYMBOL(dump_page);
#ifdef CONFIG_DEBUG_VM
-static const struct trace_print_flags vmaflag_names[] = {
- __def_vmaflag_names
-};
-
void dump_vma(const struct vm_area_struct *vma)
{
pr_emerg("vma %p start %p end %p\n"
@@ -96,7 +102,7 @@ void dump_vma(const struct vm_area_struct *vma)
(unsigned long)pgprot_val(vma->vm_page_prot),
vma->anon_vma, vma->vm_ops, vma->vm_pgoff,
vma->vm_file, vma->vm_private_data);
- dump_flags(vma->vm_flags, vmaflag_names, ARRAY_SIZE(vmaflag_names));
+ dump_flags(vma->vm_flags, vmaflag_names, ARRAY_SIZE(vmaflag_names) - 1);
}
EXPORT_SYMBOL(dump_vma);
@@ -168,7 +174,7 @@ void dump_mm(const struct mm_struct *mm)
);
dump_flags(mm->def_flags, vmaflag_names,
- ARRAY_SIZE(vmaflag_names));
+ ARRAY_SIZE(vmaflag_names) - 1);
}
#endif /* CONFIG_DEBUG_VM */
diff --git a/mm/internal.h b/mm/internal.h
index a38a21ebddb454540fc1dcae83be516ffc7cdf26..6636e1d3ecf0b53b52063eb1bc402a0e1648aa3b 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -14,6 +14,7 @@
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/pagemap.h>
+#include <linux/tracepoint-defs.h>
/*
* The set of flags that only affect watermark checking and reclaim
@@ -466,4 +467,9 @@ static inline void try_to_unmap_flush_dirty(void)
}
#endif /* CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH */
+
+extern const struct trace_print_flags pageflag_names[];
+extern const struct trace_print_flags vmaflag_names[];
+extern const struct trace_print_flags gfpflag_names[];
+
#endif /* __MM_INTERNAL_H */