With this config:
http://busybox.net/~vda/kernel_config_OPTIMIZE_INLINING_and_Os
gcc-4.7.2 generates many copies of these tiny functions:
bitmap_weight (55 copies):
55 push %rbp
48 89 e5 mov %rsp,%rbp
e8 3f 3a 8b 00 callq __bitmap_weight
5d pop %rbp
c3 retq
hweight_long (23 copies):
55 push %rbp
e8 b5 65 8e 00 callq __sw_hweight64
48 89 e5 mov %rsp,%rbp
5d pop %rbp
c3 retq
See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66122
This patch fixes this via s/inline/__always_inline/
While at it, replaced two "__inline__" with usual "inline"
(the rest of the source file uses the latter).
text data bss dec filename
86971357 17195880 36659200 140826437 vmlinux.before
86971120 17195912 36659200 140826232 vmlinux
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1438697716-28121-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
return find_first_zero_bit(src, nbits) == nbits;
}
-static inline int bitmap_weight(const unsigned long *src, unsigned int nbits)
+static __always_inline int bitmap_weight(const unsigned long *src, unsigned int nbits)
{
if (small_const_nbits(nbits))
return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits));
(bit) < (size); \
(bit) = find_next_zero_bit((addr), (size), (bit) + 1))
-static __inline__ int get_bitmask_order(unsigned int count)
+static inline int get_bitmask_order(unsigned int count)
{
int order;
return order; /* We could be slightly more clever with -1 here... */
}
-static __inline__ int get_count_order(unsigned int count)
+static inline int get_count_order(unsigned int count)
{
int order;
return order;
}
-static inline unsigned long hweight_long(unsigned long w)
+static __always_inline unsigned long hweight_long(unsigned long w)
{
return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
}