diff options
Diffstat (limited to 'Documentation/core-api/printk-formats.rst')
| -rw-r--r-- | Documentation/core-api/printk-formats.rst | 35 |
1 files changed, 26 insertions, 9 deletions
diff --git a/Documentation/core-api/printk-formats.rst b/Documentation/core-api/printk-formats.rst index 5e89497ba314..4451ef501936 100644 --- a/Documentation/core-api/printk-formats.rst +++ b/Documentation/core-api/printk-formats.rst @@ -15,9 +15,10 @@ Integer types If variable is of Type, use printk format specifier: ------------------------------------------------------------ - char %d or %x + signed char %d or %hhx unsigned char %u or %x - short int %d or %x + char %u or %x + short int %d or %hx unsigned short int %u or %x int %d or %x unsigned int %u or %x @@ -27,9 +28,9 @@ Integer types unsigned long long %llu or %llx size_t %zu or %zx ssize_t %zd or %zx - s8 %d or %x + s8 %d or %hhx u8 %u or %x - s16 %d or %x + s16 %d or %hx u16 %u or %x s32 %d or %x u32 %u or %x @@ -575,20 +576,26 @@ The field width is passed by value, the bitmap is passed by reference. Helper macros cpumask_pr_args() and nodemask_pr_args() are available to ease printing cpumask and nodemask. -Flags bitfields such as page flags, gfp_flags ---------------------------------------------- +Flags bitfields such as page flags, page_type, gfp_flags +-------------------------------------------------------- :: %pGp 0x17ffffc0002036(referenced|uptodate|lru|active|private|node=0|zone=2|lastcpupid=0x1fffff) + %pGt 0xffffff7f(buddy) %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. +character. Currently supported are: + + - p - [p]age flags, expects value of type (``unsigned long *``) + - t - page [t]ype, expects value of type (``unsigned int *``) + - v - [v]ma_flags, expects value of type (``unsigned long *``) + - g - [g]fp_flags, expects value of type (``gfp_t *``) + +The flag names and print order depends on the particular type. Note that this format should not be used directly in the :c:func:`TP_printk()` part of a tracepoint. Instead, use the show_*_flags() @@ -625,6 +632,16 @@ Examples:: %p4cc Y10 little-endian (0x20303159) %p4cc NV12 big-endian (0xb231564e) +Rust +---- + +:: + + %pA + +Only intended to be used from Rust code to format ``core::fmt::Arguments``. +Do *not* use it from C. + Thanks ====== |