Message ID | 20221006064028.548-1-jszhang@kernel.org (mailing list archive) |
---|---|
State | Superseded, archived |
Headers | show |
Series | riscv: jump_label: mark arguments as const to satisfy asm constraints | expand |
On Thu, Oct 06, 2022 at 02:40:28PM +0800, Jisheng Zhang wrote: > Samuel reported that the static branch usage in cpu_relax() breaks > building with CONFIG_CC_OPTIMIZE_FOR_SIZE[1]: > > In file included from <command-line>: > ./arch/riscv/include/asm/jump_label.h: In function 'cpu_relax': > ././include/linux/compiler_types.h:285:33: warning: 'asm' operand 0 > probably does not match constraints > 285 | #define asm_volatile_goto(x...) asm goto(x) > | ^~~ > ./arch/riscv/include/asm/jump_label.h:41:9: note: in expansion of macro > 'asm_volatile_goto' > 41 | asm_volatile_goto( > | ^~~~~~~~~~~~~~~~~ > ././include/linux/compiler_types.h:285:33: error: impossible constraint > in 'asm' > 285 | #define asm_volatile_goto(x...) asm goto(x) > | ^~~ > ./arch/riscv/include/asm/jump_label.h:41:9: note: in expansion of macro > 'asm_volatile_goto' > 41 | asm_volatile_goto( > | ^~~~~~~~~~~~~~~~~ > make[1]: *** [scripts/Makefile.build:249: > arch/riscv/kernel/vdso/vgettimeofday.o] Error 1 > make: *** [arch/riscv/Makefile:128: vdso_prepare] Error 2 > > Maybe "-Os" prevents GCC from detecting that the key/branch arguments > can be treated as constants and used as immediate operands. Inspired > by x86's commit 864b435514b2("x86/jump_label: Mark arguments as const to > satisfy asm constraints"), and as pointed out by Steven in [2] "The "i" > constraint needs to be a constant.", let's do similar modifications to > riscv. > > Tested by CC_OPTIMIZE_FOR_SIZE + gcc and CC_OPTIMIZE_FOR_SIZE + clang. > > [1]https://lore.kernel.org/linux-riscv/20220922060958.44203-1-samuel@sholland.org/ > [2]https://lore.kernel.org/all/20210212094059.5f8d05e8@gandalf.local.home/ > Signed-off-by: Jisheng Zhang <jszhang@kernel.org> > --- > arch/riscv/include/asm/jump_label.h | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/arch/riscv/include/asm/jump_label.h b/arch/riscv/include/asm/jump_label.h > index 38af2ec7b9bf..6d58bbb5da46 100644 > --- a/arch/riscv/include/asm/jump_label.h > +++ b/arch/riscv/include/asm/jump_label.h > @@ -14,8 +14,8 @@ > > #define JUMP_LABEL_NOP_SIZE 4 > > -static __always_inline bool arch_static_branch(struct static_key *key, > - bool branch) > +static __always_inline bool arch_static_branch(struct static_key * const key, > + const bool branch) > { > asm_volatile_goto( > " .option push \n\t" > @@ -35,8 +35,8 @@ static __always_inline bool arch_static_branch(struct static_key *key, > return true; > } > > -static __always_inline bool arch_static_branch_jump(struct static_key *key, > - bool branch) > +static __always_inline bool arch_static_branch_jump(struct static_key * const key, > + const bool branch) > { > asm_volatile_goto( > " .option push \n\t" > -- > 2.37.2 > Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
On 06/10/2022 13:41, Andrew Jones wrote: > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe > > On Thu, Oct 06, 2022 at 02:40:28PM +0800, Jisheng Zhang wrote: >> Samuel reported that the static branch usage in cpu_relax() breaks >> building with CONFIG_CC_OPTIMIZE_FOR_SIZE[1]: >> >> In file included from <command-line>: >> ./arch/riscv/include/asm/jump_label.h: In function 'cpu_relax': >> ././include/linux/compiler_types.h:285:33: warning: 'asm' operand 0 >> probably does not match constraints >> 285 | #define asm_volatile_goto(x...) asm goto(x) >> | ^~~ >> ./arch/riscv/include/asm/jump_label.h:41:9: note: in expansion of macro >> 'asm_volatile_goto' >> 41 | asm_volatile_goto( >> | ^~~~~~~~~~~~~~~~~ >> ././include/linux/compiler_types.h:285:33: error: impossible constraint >> in 'asm' >> 285 | #define asm_volatile_goto(x...) asm goto(x) >> | ^~~ >> ./arch/riscv/include/asm/jump_label.h:41:9: note: in expansion of macro >> 'asm_volatile_goto' >> 41 | asm_volatile_goto( >> | ^~~~~~~~~~~~~~~~~ >> make[1]: *** [scripts/Makefile.build:249: >> arch/riscv/kernel/vdso/vgettimeofday.o] Error 1 >> make: *** [arch/riscv/Makefile:128: vdso_prepare] Error 2 >> >> Maybe "-Os" prevents GCC from detecting that the key/branch arguments >> can be treated as constants and used as immediate operands. Inspired >> by x86's commit 864b435514b2("x86/jump_label: Mark arguments as const to >> satisfy asm constraints"), and as pointed out by Steven in [2] "The "i" >> constraint needs to be a constant.", let's do similar modifications to >> riscv. >> >> Tested by CC_OPTIMIZE_FOR_SIZE + gcc and CC_OPTIMIZE_FOR_SIZE + clang. >> >> [1]https://lore.kernel.org/linux-riscv/20220922060958.44203-1-samuel@sholland.org/ >> [2]https://lore.kernel.org/all/20210212094059.5f8d05e8@gandalf.local.home/ Hey Jisheng, Could you please make these normal link tags.? Also could you please add the reported-by from samuel & a fixes tag? Thanks, Conor. >> Signed-off-by: Jisheng Zhang <jszhang@kernel.org> >> --- >> arch/riscv/include/asm/jump_label.h | 8 ++++---- >> 1 file changed, 4 insertions(+), 4 deletions(-) >> >> diff --git a/arch/riscv/include/asm/jump_label.h b/arch/riscv/include/asm/jump_label.h >> index 38af2ec7b9bf..6d58bbb5da46 100644 >> --- a/arch/riscv/include/asm/jump_label.h >> +++ b/arch/riscv/include/asm/jump_label.h >> @@ -14,8 +14,8 @@ >> >> #define JUMP_LABEL_NOP_SIZE 4 >> >> -static __always_inline bool arch_static_branch(struct static_key *key, >> - bool branch) >> +static __always_inline bool arch_static_branch(struct static_key * const key, >> + const bool branch) >> { >> asm_volatile_goto( >> " .option push \n\t" >> @@ -35,8 +35,8 @@ static __always_inline bool arch_static_branch(struct static_key *key, >> return true; >> } >> >> -static __always_inline bool arch_static_branch_jump(struct static_key *key, >> - bool branch) >> +static __always_inline bool arch_static_branch_jump(struct static_key * const key, >> + const bool branch) >> { >> asm_volatile_goto( >> " .option push \n\t" >> -- >> 2.37.2 >> > > Reviewed-by: Andrew Jones <ajones@ventanamicro.com> > > _______________________________________________ > linux-riscv mailing list > linux-riscv@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-riscv
On Thu, Oct 06, 2022 at 12:44:32PM +0000, Conor.Dooley@microchip.com wrote: > On 06/10/2022 13:41, Andrew Jones wrote: > > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe > > > > On Thu, Oct 06, 2022 at 02:40:28PM +0800, Jisheng Zhang wrote: > >> Samuel reported that the static branch usage in cpu_relax() breaks > >> building with CONFIG_CC_OPTIMIZE_FOR_SIZE[1]: > >> > >> In file included from <command-line>: > >> ./arch/riscv/include/asm/jump_label.h: In function 'cpu_relax': > >> ././include/linux/compiler_types.h:285:33: warning: 'asm' operand 0 > >> probably does not match constraints > >> 285 | #define asm_volatile_goto(x...) asm goto(x) > >> | ^~~ > >> ./arch/riscv/include/asm/jump_label.h:41:9: note: in expansion of macro > >> 'asm_volatile_goto' > >> 41 | asm_volatile_goto( > >> | ^~~~~~~~~~~~~~~~~ > >> ././include/linux/compiler_types.h:285:33: error: impossible constraint > >> in 'asm' > >> 285 | #define asm_volatile_goto(x...) asm goto(x) > >> | ^~~ > >> ./arch/riscv/include/asm/jump_label.h:41:9: note: in expansion of macro > >> 'asm_volatile_goto' > >> 41 | asm_volatile_goto( > >> | ^~~~~~~~~~~~~~~~~ > >> make[1]: *** [scripts/Makefile.build:249: > >> arch/riscv/kernel/vdso/vgettimeofday.o] Error 1 > >> make: *** [arch/riscv/Makefile:128: vdso_prepare] Error 2 > >> > >> Maybe "-Os" prevents GCC from detecting that the key/branch arguments > >> can be treated as constants and used as immediate operands. Inspired > >> by x86's commit 864b435514b2("x86/jump_label: Mark arguments as const to > >> satisfy asm constraints"), and as pointed out by Steven in [2] "The "i" > >> constraint needs to be a constant.", let's do similar modifications to > >> riscv. > >> > >> Tested by CC_OPTIMIZE_FOR_SIZE + gcc and CC_OPTIMIZE_FOR_SIZE + clang. > >> > >> [1]https://lore.kernel.org/linux-riscv/20220922060958.44203-1-samuel@sholland.org/ > >> [2]https://lore.kernel.org/all/20210212094059.5f8d05e8@gandalf.local.home/ > > Hey Jisheng, Hi, > > Could you please make these normal link tags.? How to make these link tags? I just used the permalink in lore.kernel.org > Also could you please add the reported-by from samuel & a fixes tag? I will add Reported-by tag, but I'm not sure whether fixes tag is suitable, and which commit I could use? commit 8eb060e1018 ("arch/riscv: add Zihintpause support")? > > Thanks, > Conor. > > >> Signed-off-by: Jisheng Zhang <jszhang@kernel.org> > >> --- > >> arch/riscv/include/asm/jump_label.h | 8 ++++---- > >> 1 file changed, 4 insertions(+), 4 deletions(-) > >> > >> diff --git a/arch/riscv/include/asm/jump_label.h b/arch/riscv/include/asm/jump_label.h > >> index 38af2ec7b9bf..6d58bbb5da46 100644 > >> --- a/arch/riscv/include/asm/jump_label.h > >> +++ b/arch/riscv/include/asm/jump_label.h > >> @@ -14,8 +14,8 @@ > >> > >> #define JUMP_LABEL_NOP_SIZE 4 > >> > >> -static __always_inline bool arch_static_branch(struct static_key *key, > >> - bool branch) > >> +static __always_inline bool arch_static_branch(struct static_key * const key, > >> + const bool branch) > >> { > >> asm_volatile_goto( > >> " .option push \n\t" > >> @@ -35,8 +35,8 @@ static __always_inline bool arch_static_branch(struct static_key *key, > >> return true; > >> } > >> > >> -static __always_inline bool arch_static_branch_jump(struct static_key *key, > >> - bool branch) > >> +static __always_inline bool arch_static_branch_jump(struct static_key * const key, > >> + const bool branch) > >> { > >> asm_volatile_goto( > >> " .option push \n\t" > >> -- > >> 2.37.2 > >> > > > > Reviewed-by: Andrew Jones <ajones@ventanamicro.com> > > > > _______________________________________________ > > linux-riscv mailing list > > linux-riscv@lists.infradead.org > > http://lists.infradead.org/mailman/listinfo/linux-riscv >
On Sat, 8 Oct 2022 21:55:07 +0800 Jisheng Zhang <jszhang@kernel.org> wrote: > > >> [1]https://lore.kernel.org/linux-riscv/20220922060958.44203-1-samuel@sholland.org/ > > >> [2]https://lore.kernel.org/all/20210212094059.5f8d05e8@gandalf.local.home/ > > > > > > Could you please make these normal link tags.? > > How to make these link tags? I just used the permalink in > lore.kernel.org Link: https://lore.kernel.org/linux-riscv/20220922060958.44203-1-samuel@sholland.org/ Link: https://lore.kernel.org/all/20210212094059.5f8d05e8@gandalf.local.home/ -- Steve
On Sat, Oct 08, 2022 at 10:09:02AM -0400, Steven Rostedt wrote: > On Sat, 8 Oct 2022 10:07:48 -0400 > Steven Rostedt <rostedt@goodmis.org> wrote: > > > Link: https://lore.kernel.org/linux-riscv/20220922060958.44203-1-samuel@sholland.org/ > > Link: https://lore.kernel.org/all/20210212094059.5f8d05e8@gandalf.local.home/ > > > > This way tools can be used to map commits to links relevant to them. > They key off the "Link:" tag keyword. Thank you so much!
On Sat, 8 Oct 2022 10:07:48 -0400 Steven Rostedt <rostedt@goodmis.org> wrote: > Link: https://lore.kernel.org/linux-riscv/20220922060958.44203-1-samuel@sholland.org/ > Link: https://lore.kernel.org/all/20210212094059.5f8d05e8@gandalf.local.home/ > This way tools can be used to map commits to links relevant to them. They key off the "Link:" tag keyword. -- Steve
On Sat, Oct 08, 2022 at 09:55:07PM +0800, Jisheng Zhang wrote: > On Thu, Oct 06, 2022 at 12:44:32PM +0000, Conor.Dooley@microchip.com wrote: > > Also could you please add the reported-by from samuel & a fixes tag? > > I will add Reported-by tag, but I'm not sure whether fixes tag > is suitable, and which commit I could use? commit 8eb060e1018 > ("arch/riscv: add Zihintpause support")? That is the commit that Samuel blamed for the issue & is the one that added the static branch - so I guess so! Thanks, Conor.
Am Donnerstag, 6. Oktober 2022, 08:40:28 CEST schrieb Jisheng Zhang: > Samuel reported that the static branch usage in cpu_relax() breaks > building with CONFIG_CC_OPTIMIZE_FOR_SIZE[1]: > > In file included from <command-line>: > ./arch/riscv/include/asm/jump_label.h: In function 'cpu_relax': > ././include/linux/compiler_types.h:285:33: warning: 'asm' operand 0 > probably does not match constraints > 285 | #define asm_volatile_goto(x...) asm goto(x) > | ^~~ > ./arch/riscv/include/asm/jump_label.h:41:9: note: in expansion of macro > 'asm_volatile_goto' > 41 | asm_volatile_goto( > | ^~~~~~~~~~~~~~~~~ > ././include/linux/compiler_types.h:285:33: error: impossible constraint > in 'asm' > 285 | #define asm_volatile_goto(x...) asm goto(x) > | ^~~ > ./arch/riscv/include/asm/jump_label.h:41:9: note: in expansion of macro > 'asm_volatile_goto' > 41 | asm_volatile_goto( > | ^~~~~~~~~~~~~~~~~ > make[1]: *** [scripts/Makefile.build:249: > arch/riscv/kernel/vdso/vgettimeofday.o] Error 1 > make: *** [arch/riscv/Makefile:128: vdso_prepare] Error 2 > > Maybe "-Os" prevents GCC from detecting that the key/branch arguments > can be treated as constants and used as immediate operands. Inspired > by x86's commit 864b435514b2("x86/jump_label: Mark arguments as const to > satisfy asm constraints"), and as pointed out by Steven in [2] "The "i" > constraint needs to be a constant.", let's do similar modifications to > riscv. > > Tested by CC_OPTIMIZE_FOR_SIZE + gcc and CC_OPTIMIZE_FOR_SIZE + clang. I ran into the same build-issue when enabling CC_OPTIMIZE_FOR_SIZE and this patch fixes it, so Tested-by: Heiko Stuebner <heiko@sntech.de> > [1]https://lore.kernel.org/linux-riscv/20220922060958.44203-1-samuel@sholland.org/ > [2]https://lore.kernel.org/all/20210212094059.5f8d05e8@gandalf.local.home/ > Signed-off-by: Jisheng Zhang <jszhang@kernel.org> > --- > arch/riscv/include/asm/jump_label.h | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/arch/riscv/include/asm/jump_label.h b/arch/riscv/include/asm/jump_label.h > index 38af2ec7b9bf..6d58bbb5da46 100644 > --- a/arch/riscv/include/asm/jump_label.h > +++ b/arch/riscv/include/asm/jump_label.h > @@ -14,8 +14,8 @@ > > #define JUMP_LABEL_NOP_SIZE 4 > > -static __always_inline bool arch_static_branch(struct static_key *key, > - bool branch) > +static __always_inline bool arch_static_branch(struct static_key * const key, > + const bool branch) > { > asm_volatile_goto( > " .option push \n\t" > @@ -35,8 +35,8 @@ static __always_inline bool arch_static_branch(struct static_key *key, > return true; > } > > -static __always_inline bool arch_static_branch_jump(struct static_key *key, > - bool branch) > +static __always_inline bool arch_static_branch_jump(struct static_key * const key, > + const bool branch) > { > asm_volatile_goto( > " .option push \n\t" >
diff --git a/arch/riscv/include/asm/jump_label.h b/arch/riscv/include/asm/jump_label.h index 38af2ec7b9bf..6d58bbb5da46 100644 --- a/arch/riscv/include/asm/jump_label.h +++ b/arch/riscv/include/asm/jump_label.h @@ -14,8 +14,8 @@ #define JUMP_LABEL_NOP_SIZE 4 -static __always_inline bool arch_static_branch(struct static_key *key, - bool branch) +static __always_inline bool arch_static_branch(struct static_key * const key, + const bool branch) { asm_volatile_goto( " .option push \n\t" @@ -35,8 +35,8 @@ static __always_inline bool arch_static_branch(struct static_key *key, return true; } -static __always_inline bool arch_static_branch_jump(struct static_key *key, - bool branch) +static __always_inline bool arch_static_branch_jump(struct static_key * const key, + const bool branch) { asm_volatile_goto( " .option push \n\t"
Samuel reported that the static branch usage in cpu_relax() breaks building with CONFIG_CC_OPTIMIZE_FOR_SIZE[1]: In file included from <command-line>: ./arch/riscv/include/asm/jump_label.h: In function 'cpu_relax': ././include/linux/compiler_types.h:285:33: warning: 'asm' operand 0 probably does not match constraints 285 | #define asm_volatile_goto(x...) asm goto(x) | ^~~ ./arch/riscv/include/asm/jump_label.h:41:9: note: in expansion of macro 'asm_volatile_goto' 41 | asm_volatile_goto( | ^~~~~~~~~~~~~~~~~ ././include/linux/compiler_types.h:285:33: error: impossible constraint in 'asm' 285 | #define asm_volatile_goto(x...) asm goto(x) | ^~~ ./arch/riscv/include/asm/jump_label.h:41:9: note: in expansion of macro 'asm_volatile_goto' 41 | asm_volatile_goto( | ^~~~~~~~~~~~~~~~~ make[1]: *** [scripts/Makefile.build:249: arch/riscv/kernel/vdso/vgettimeofday.o] Error 1 make: *** [arch/riscv/Makefile:128: vdso_prepare] Error 2 Maybe "-Os" prevents GCC from detecting that the key/branch arguments can be treated as constants and used as immediate operands. Inspired by x86's commit 864b435514b2("x86/jump_label: Mark arguments as const to satisfy asm constraints"), and as pointed out by Steven in [2] "The "i" constraint needs to be a constant.", let's do similar modifications to riscv. Tested by CC_OPTIMIZE_FOR_SIZE + gcc and CC_OPTIMIZE_FOR_SIZE + clang. [1]https://lore.kernel.org/linux-riscv/20220922060958.44203-1-samuel@sholland.org/ [2]https://lore.kernel.org/all/20210212094059.5f8d05e8@gandalf.local.home/ Signed-off-by: Jisheng Zhang <jszhang@kernel.org> --- arch/riscv/include/asm/jump_label.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)