diff options
| -rw-r--r-- | Documentation/printk-formats.txt | 18 | ||||
| -rw-r--r-- | lib/test_printf.c | 53 | ||||
| -rw-r--r-- | lib/vsprintf.c | 75 | ||||
| -rw-r--r-- | mm/debug.c | 34 | ||||
| -rw-r--r-- | mm/internal.h | 6 |
5 files changed, 172 insertions, 14 deletions
diff --git a/Documentation/printk-formats.txt b/Documentation/printk-formats.txt index 5d1128b..5962949 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 4f6ae60..563f10e 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 '$' @@ -411,6 +414,55 @@ 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) { plain(); @@ -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 f44e178..525c8e1 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) { @@ -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 a38a21e..6636e1d 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 */ |
