335 lines
10 KiB
Plaintext
335 lines
10 KiB
Plaintext
If variable is of Type, use printk format specifier:
|
|
---------------------------------------------------------
|
|
int %d or %x
|
|
unsigned int %u or %x
|
|
long %ld or %lx
|
|
unsigned long %lu or %lx
|
|
long long %lld or %llx
|
|
unsigned long long %llu or %llx
|
|
size_t %zu or %zx
|
|
ssize_t %zd or %zx
|
|
s32 %d or %x
|
|
u32 %u or %x
|
|
s64 %lld or %llx
|
|
u64 %llu or %llx
|
|
|
|
If <type> is dependent on a config option for its size (e.g., sector_t,
|
|
blkcnt_t) or is architecture-dependent for its size (e.g., tcflag_t), use a
|
|
format specifier of its largest possible type and explicitly cast to it.
|
|
Example:
|
|
|
|
printk("test: sector number/total blocks: %llu/%llu\n",
|
|
(unsigned long long)sector, (unsigned long long)blockcount);
|
|
|
|
Reminder: sizeof() result is of type size_t.
|
|
|
|
The kernel's printf does not support %n. For obvious reasons, floating
|
|
point formats (%e, %f, %g, %a) are also not recognized. Use of any
|
|
unsupported specifier or length qualifier results in a WARN and early
|
|
return from vsnprintf.
|
|
|
|
Raw pointer value SHOULD be printed with %p. The kernel supports
|
|
the following extended format specifiers for pointer types:
|
|
|
|
Symbols/Function Pointers:
|
|
|
|
%pF versatile_init+0x0/0x110
|
|
%pf versatile_init
|
|
%pS versatile_init+0x0/0x110
|
|
%pSR versatile_init+0x9/0x110
|
|
(with __builtin_extract_return_addr() translation)
|
|
%ps versatile_init
|
|
%pB prev_fn_of_versatile_init+0x88/0x88
|
|
|
|
For printing symbols and function pointers. The 'S' and 's' specifiers
|
|
result in the symbol name with ('S') or without ('s') offsets. Where
|
|
this is used on a kernel without KALLSYMS - the symbol address is
|
|
printed instead.
|
|
|
|
The 'B' specifier results in the symbol name with offsets and should be
|
|
used when printing stack backtraces. The specifier takes into
|
|
consideration the effect of compiler optimisations which may occur
|
|
when tail-call's are used and marked with the noreturn GCC attribute.
|
|
|
|
On ia64, ppc64 and parisc64 architectures function pointers are
|
|
actually function descriptors which must first be resolved. The 'F' and
|
|
'f' specifiers perform this resolution and then provide the same
|
|
functionality as the 'S' and 's' specifiers.
|
|
|
|
Kernel Pointers:
|
|
|
|
%pK 0x01234567 or 0x0123456789abcdef
|
|
|
|
For printing kernel pointers which should be hidden from unprivileged
|
|
users. The behaviour of %pK depends on the kptr_restrict sysctl - see
|
|
Documentation/sysctl/kernel.txt for more details.
|
|
|
|
Struct Resources:
|
|
|
|
%pr [mem 0x60000000-0x6fffffff flags 0x2200] or
|
|
[mem 0x0000000060000000-0x000000006fffffff flags 0x2200]
|
|
%pR [mem 0x60000000-0x6fffffff pref] or
|
|
[mem 0x0000000060000000-0x000000006fffffff pref]
|
|
|
|
For printing struct resources. The 'R' and 'r' specifiers result in a
|
|
printed resource with ('R') or without ('r') a decoded flags member.
|
|
Passed by reference.
|
|
|
|
Physical addresses types phys_addr_t:
|
|
|
|
%pa[p] 0x01234567 or 0x0123456789abcdef
|
|
|
|
For printing a phys_addr_t type (and its derivatives, such as
|
|
resource_size_t) which can vary based on build options, regardless of
|
|
the width of the CPU data path. Passed by reference.
|
|
|
|
DMA addresses types dma_addr_t:
|
|
|
|
%pad 0x01234567 or 0x0123456789abcdef
|
|
|
|
For printing a dma_addr_t type which can vary based on build options,
|
|
regardless of the width of the CPU data path. Passed by reference.
|
|
|
|
Raw buffer as an escaped string:
|
|
|
|
%*pE[achnops]
|
|
|
|
For printing raw buffer as an escaped string. For the following buffer
|
|
|
|
1b 62 20 5c 43 07 22 90 0d 5d
|
|
|
|
few examples show how the conversion would be done (the result string
|
|
without surrounding quotes):
|
|
|
|
%*pE "\eb \C\a"\220\r]"
|
|
%*pEhp "\x1bb \C\x07"\x90\x0d]"
|
|
%*pEa "\e\142\040\\\103\a\042\220\r\135"
|
|
|
|
The conversion rules are applied according to an optional combination
|
|
of flags (see string_escape_mem() kernel documentation for the
|
|
details):
|
|
a - ESCAPE_ANY
|
|
c - ESCAPE_SPECIAL
|
|
h - ESCAPE_HEX
|
|
n - ESCAPE_NULL
|
|
o - ESCAPE_OCTAL
|
|
p - ESCAPE_NP
|
|
s - ESCAPE_SPACE
|
|
By default ESCAPE_ANY_NP is used.
|
|
|
|
ESCAPE_ANY_NP is the sane choice for many cases, in particularly for
|
|
printing SSIDs.
|
|
|
|
If field width is omitted the 1 byte only will be escaped.
|
|
|
|
Raw buffer as a hex string:
|
|
|
|
%*ph 00 01 02 ... 3f
|
|
%*phC 00:01:02: ... :3f
|
|
%*phD 00-01-02- ... -3f
|
|
%*phN 000102 ... 3f
|
|
|
|
For printing a small buffers (up to 64 bytes long) as a hex string with
|
|
certain separator. For the larger buffers consider to use
|
|
print_hex_dump().
|
|
|
|
MAC/FDDI addresses:
|
|
|
|
%pM 00:01:02:03:04:05
|
|
%pMR 05:04:03:02:01:00
|
|
%pMF 00-01-02-03-04-05
|
|
%pm 000102030405
|
|
%pmR 050403020100
|
|
|
|
For printing 6-byte MAC/FDDI addresses in hex notation. The 'M' and 'm'
|
|
specifiers result in a printed address with ('M') or without ('m') byte
|
|
separators. The default byte separator is the colon (':').
|
|
|
|
Where FDDI addresses are concerned the 'F' specifier can be used after
|
|
the 'M' specifier to use dash ('-') separators instead of the default
|
|
separator.
|
|
|
|
For Bluetooth addresses the 'R' specifier shall be used after the 'M'
|
|
specifier to use reversed byte order suitable for visual interpretation
|
|
of Bluetooth addresses which are in the little endian order.
|
|
|
|
Passed by reference.
|
|
|
|
IPv4 addresses:
|
|
|
|
%pI4 1.2.3.4
|
|
%pi4 001.002.003.004
|
|
%p[Ii]4[hnbl]
|
|
|
|
For printing IPv4 dot-separated decimal addresses. The 'I4' and 'i4'
|
|
specifiers result in a printed address with ('i4') or without ('I4')
|
|
leading zeros.
|
|
|
|
The additional 'h', 'n', 'b', and 'l' specifiers are used to specify
|
|
host, network, big or little endian order addresses respectively. Where
|
|
no specifier is provided the default network/big endian order is used.
|
|
|
|
Passed by reference.
|
|
|
|
IPv6 addresses:
|
|
|
|
%pI6 0001:0002:0003:0004:0005:0006:0007:0008
|
|
%pi6 00010002000300040005000600070008
|
|
%pI6c 1:2:3:4:5:6:7:8
|
|
|
|
For printing IPv6 network-order 16-bit hex addresses. The 'I6' and 'i6'
|
|
specifiers result in a printed address with ('I6') or without ('i6')
|
|
colon-separators. Leading zeros are always used.
|
|
|
|
The additional 'c' specifier can be used with the 'I' specifier to
|
|
print a compressed IPv6 address as described by
|
|
http://tools.ietf.org/html/rfc5952
|
|
|
|
Passed by reference.
|
|
|
|
IPv4/IPv6 addresses (generic, with port, flowinfo, scope):
|
|
|
|
%pIS 1.2.3.4 or 0001:0002:0003:0004:0005:0006:0007:0008
|
|
%piS 001.002.003.004 or 00010002000300040005000600070008
|
|
%pISc 1.2.3.4 or 1:2:3:4:5:6:7:8
|
|
%pISpc 1.2.3.4:12345 or [1:2:3:4:5:6:7:8]:12345
|
|
%p[Ii]S[pfschnbl]
|
|
|
|
For printing an IP address without the need to distinguish whether it's
|
|
of type AF_INET or AF_INET6, a pointer to a valid 'struct sockaddr',
|
|
specified through 'IS' or 'iS', can be passed to this format specifier.
|
|
|
|
The additional 'p', 'f', and 's' specifiers are used to specify port
|
|
(IPv4, IPv6), flowinfo (IPv6) and scope (IPv6). Ports have a ':' prefix,
|
|
flowinfo a '/' and scope a '%', each followed by the actual value.
|
|
|
|
In case of an IPv6 address the compressed IPv6 address as described by
|
|
http://tools.ietf.org/html/rfc5952 is being used if the additional
|
|
specifier 'c' is given. The IPv6 address is surrounded by '[', ']' in
|
|
case of additional specifiers 'p', 'f' or 's' as suggested by
|
|
https://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-07
|
|
|
|
In case of IPv4 addresses, the additional 'h', 'n', 'b', and 'l'
|
|
specifiers can be used as well and are ignored in case of an IPv6
|
|
address.
|
|
|
|
Passed by reference.
|
|
|
|
Further examples:
|
|
|
|
%pISfc 1.2.3.4 or [1:2:3:4:5:6:7:8]/123456789
|
|
%pISsc 1.2.3.4 or [1:2:3:4:5:6:7:8]%1234567890
|
|
%pISpfc 1.2.3.4:12345 or [1:2:3:4:5:6:7:8]:12345/123456789
|
|
|
|
UUID/GUID addresses:
|
|
|
|
%pUb 00010203-0405-0607-0809-0a0b0c0d0e0f
|
|
%pUB 00010203-0405-0607-0809-0A0B0C0D0E0F
|
|
%pUl 03020100-0504-0706-0809-0a0b0c0e0e0f
|
|
%pUL 03020100-0504-0706-0809-0A0B0C0E0E0F
|
|
|
|
For printing 16-byte UUID/GUIDs addresses. The additional 'l', 'L',
|
|
'b' and 'B' specifiers are used to specify a little endian order in
|
|
lower ('l') or upper case ('L') hex characters - and big endian order
|
|
in lower ('b') or upper case ('B') hex characters.
|
|
|
|
Where no additional specifiers are used the default big endian
|
|
order with lower case hex characters will be printed.
|
|
|
|
Passed by reference.
|
|
|
|
dentry names:
|
|
|
|
%pd{,2,3,4}
|
|
%pD{,2,3,4}
|
|
|
|
For printing dentry name; if we race with d_move(), the name might be
|
|
a mix of old and new ones, but it won't oops. %pd dentry is a safer
|
|
equivalent of %s dentry->d_name.name we used to use, %pd<n> prints
|
|
n last components. %pD does the same thing for struct file.
|
|
|
|
Passed by reference.
|
|
|
|
block_device names:
|
|
|
|
%pg sda, sda1 or loop0p1
|
|
|
|
For printing name of block_device pointers.
|
|
|
|
struct va_format:
|
|
|
|
%pV
|
|
|
|
For printing struct va_format structures. These contain a format string
|
|
and va_list as follows:
|
|
|
|
struct va_format {
|
|
const char *fmt;
|
|
va_list *va;
|
|
};
|
|
|
|
Implements a "recursive vsnprintf".
|
|
|
|
Do not use this feature without some mechanism to verify the
|
|
correctness of the format string and va_list arguments.
|
|
|
|
Passed by reference.
|
|
|
|
struct clk:
|
|
|
|
%pC pll1
|
|
%pCn pll1
|
|
|
|
For printing struct clk structures. '%pC' and '%pCn' print the name
|
|
(Common Clock Framework) or address (legacy clock framework) of the
|
|
structure.
|
|
|
|
Passed by reference.
|
|
|
|
bitmap and its derivatives such as cpumask and nodemask:
|
|
|
|
%*pb 0779
|
|
%*pbl 0,3-6,8-10
|
|
|
|
For printing bitmap and its derivatives such as cpumask and nodemask,
|
|
%*pb output the bitmap with field width as the number of bits and %*pbl
|
|
output the bitmap as range list with field width as the number of bits.
|
|
|
|
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
|
|
|
|
For printing netdev_features_t.
|
|
|
|
Passed by reference.
|
|
|
|
If you add other %p extensions, please extend lib/test_printf.c with
|
|
one or more test cases, if at all feasible.
|
|
|
|
|
|
Thank you for your cooperation and attention.
|
|
|
|
|
|
By Randy Dunlap <rdunlap@infradead.org> and
|
|
Andrew Murray <amurray@mpc-data.co.uk>
|