dynamic_debug: add jump label support
Although dynamic debug is often only used for debug builds, sometimes its enabled for production builds as well. Minimize its impact by using jump labels. This reduces the text section by 7000+ bytes in the kernel image below. It does increase data, but this should only be referenced when changing the direction of the branches, and hence usually not in cache. text data bss dec hex filename 8194852 4879776 925696 14000324 d5a0c4 vmlinux.pre 8187337 4960224 925696 14073257 d6bda9 vmlinux.post Link: http://lkml.kernel.org/r/d165b465e8c89bc582d973758d40be44c33f018b.1467837322.git.jbaron@akamai.comSigned-off-by: NJason Baron <jbaron@akamai.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Joe Perches <joe@perches.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
Showing
想要评论请 注册 或 登录