The patch titled
Subject: include/linux/pfn_t.h: force '~' to be parsed as an unary operator
has been added to the -mm tree. Its filename is
pfn_t-force-to-be-parsed-as-an-unary-operator.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/pfn_t-force-to-be-parsed-as-an-unary-operator.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/pfn_t-force-to-be-parsed-as-an-unary-operator.patch
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------------------------------------------------------
From: Sebastien Boisvert <sebhtml@xxxxxxxxxxxxxxx>
Subject: include/linux/pfn_t.h: force '~' to be parsed as an unary operator
Tracing the event "fs_dax:dax_pmd_insert_mapping" with perf produces this
warning:
[fs_dax:dax_pmd_insert_mapping] unknown op '~'
It is printed in process_op (tools/lib/traceevent/event-parse.c) because
'~' is parsed as a binary operator.
perf reads the format of fs_dax:dax_pmd_insert_mapping ("print fmt") from
/sys/kernel/debug/tracing/events/fs_dax/dax_pmd_insert_mapping/format .
The format contains:
~(((u64) ~(~(((1UL) << 12)-1)))
^
\ interpreted as a binary operator by process_op().
This part is generated in the declaration of the event class
dax_pmd_insert_mapping_class in include/trace/events/fs_dax.h :
__print_flags_u64(__entry->pfn_val & PFN_FLAGS_MASK, "|",
PFN_FLAGS_TRACE),
This patch adds a pair of parentheses in the declaration of PFN_FLAGS_MASK
to make sure that '~' is parsed as a unary operator by perf.
The part of the format that was problematic is now:
~(((u64) (~(~(((1UL) << 12)-1))))
Now, all the '~' are parsed as unary operators.
Link: http://lkml.kernel.org/r/20181021145939.8760-1-sebhtml@xxxxxxxxxxxxxxx
Signed-off-by: Sebastien Boisvert <sebhtml@xxxxxxxxxxxxxxx>
Acked-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: "Steven Rostedt (VMware)" <rostedt@xxxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: "Tzvetomir Stoyanov (VMware)" <tz.stoyanov@xxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Ross Zwisler <zwisler@xxxxxxxxxx>
Cc: Elenie Godzaridis <arangradient@xxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/pfn_t.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/include/linux/pfn_t.h~pfn_t-force-to-be-parsed-as-an-unary-operator
+++ a/include/linux/pfn_t.h
@@ -10,7 +10,7 @@
* PFN_DEV - pfn is not covered by system memmap by default
* PFN_MAP - pfn has a dynamic page mapping established by a device driver
*/
-#define PFN_FLAGS_MASK (((u64) ~PAGE_MASK) << (BITS_PER_LONG_LONG - PAGE_SHIFT))
+#define PFN_FLAGS_MASK (((u64) (~PAGE_MASK)) << (BITS_PER_LONG_LONG - PAGE_SHIFT))
#define PFN_SG_CHAIN (1ULL << (BITS_PER_LONG_LONG - 1))
#define PFN_SG_LAST (1ULL << (BITS_PER_LONG_LONG - 2))
#define PFN_DEV (1ULL << (BITS_PER_LONG_LONG - 3))
_
Patches currently in -mm which might be from sebhtml@xxxxxxxxxxxxxxx are
pfn_t-force-to-be-parsed-as-an-unary-operator.patch
