| Message ID | 20240129164514.73104-6-philmd@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | hw, target: Prefer fast cpu_env() over slower CPU QOM cast macro | expand |
On 29/1/24 17:44, Philippe Mathieu-Daudé wrote: > Add a Coccinelle script to convert the following slow path > (due to the QOM cast macro): > > &ARCH_CPU(..)->env > > to the following fast path: > > cpu_env(..) > > Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> > --- Changes since v2: - Avoid templates by using coccinelle generic types - Deal with uaccess API (by skipping functions using it) > MAINTAINERS | 1 + > scripts/coccinelle/cpu_env.cocci | 100 +++++++++++++++++++++++++++++++ > 2 files changed, 101 insertions(+) > create mode 100644 scripts/coccinelle/cpu_env.cocci > > diff --git a/MAINTAINERS b/MAINTAINERS > index dfaca8323e..ca3c8c18ab 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -157,6 +157,7 @@ F: accel/tcg/ > F: accel/stubs/tcg-stub.c > F: util/cacheinfo.c > F: util/cacheflush.c > +F: scripts/coccinelle/cpu_env.cocci > F: scripts/decodetree.py > F: docs/devel/decodetree.rst > F: docs/devel/tcg* > diff --git a/scripts/coccinelle/cpu_env.cocci b/scripts/coccinelle/cpu_env.cocci > new file mode 100644 > index 0000000000..5a70c2211a > --- /dev/null > +++ b/scripts/coccinelle/cpu_env.cocci > @@ -0,0 +1,100 @@ > +/* > + * Convert &ARCH_CPU(..)->env to use cpu_env(..). > + * > + * Rationale: ARCH_CPU() might be slow, being a QOM cast macro. > + * cpu_env() is its fast equivalent. > + * CPU() macro is a no-op. > + * > + * SPDX-License-Identifier: GPL-2.0-or-later > + * SPDX-FileCopyrightText: Linaro Ltd 2024 > + * SPDX-FileContributor: Philippe Mathieu-Daudé > + */ > + > +@@ > +type ArchCPU =~ "CPU$"; > +identifier cpu; > +type CPUArchState =~ "^CPU"; > +identifier env; > +@@ > + ArchCPU *cpu; > + ... > + CPUArchState *env = &cpu->env; > + <... > +- &cpu->env > ++ env > + ...> > + > + > +/* > + * Due to commit 8ce5c64499 ("semihosting: Return failure from > + * softmmu-uaccess.h functions"), skip functions using softmmu-uaccess.h > + * macros (they don't pass 'env' as argument). > + */ > +@ uaccess_api_used exists @ > +identifier semihosting_func =~ "^(put|get)_user_[us](al|8|16|32)$"; > +@@ > + semihosting_func(...) Hmm, s/semihosting/uaccess/ > + > + > +/* > + * Argument is CPUState* > + */ > +@ cpustate_arg depends on !uaccess_api_used @ > +identifier cpu; > +type ArchCPU =~ "CPU$"; > +type CPUArchState; > +identifier ARCH_CPU =~ "CPU$"; > +identifier env; > +CPUState *cs; > +@@ > +- ArchCPU *cpu = ARCH_CPU(cs); > + ... > +- CPUArchState *env = &cpu->env; > ++ CPUArchState *env = cpu_env(cs); > + ... when != cpu > + > + > +/* > + * Argument is not CPUState* but a related QOM object. > + * CPU() is not a QOM macro but a cast (See commit 0d6d1ab499). > + */ > +@ depends on !uaccess_api_used && !cpustate_arg @ > +identifier cpu; > +type ArchCPU =~ "CPU$"; > +type CPUArchState; > +identifier ARCH_CPU =~ "CPU$"; > +identifier env; > +expression cs; > +@@ > +- ArchCPU *cpu = ARCH_CPU(cs); > + ... > +- CPUArchState *env = &cpu->env; > ++ CPUArchState *env = cpu_env(CPU(cs)); > + ... when != cpu > + > + > +/* When single use of 'env', call cpu_env() in place */ > +@ depends on !uaccess_api_used @ > +type CPUArchState; > +identifier env; > +expression cs; > +@@ > +- CPUArchState *env = cpu_env(cs); > + ... when != env > +- env > ++ cpu_env(cs) > + ... when != env > + > + > +/* Both first_cpu/current_cpu are extern CPUState* */ > +@@ > +symbol first_cpu; > +symbol current_cpu; > +@@ > +( > +- CPU(first_cpu) > ++ first_cpu > +| > +- CPU(current_cpu) > ++ current_cpu > +)
diff --git a/MAINTAINERS b/MAINTAINERS index dfaca8323e..ca3c8c18ab 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -157,6 +157,7 @@ F: accel/tcg/ F: accel/stubs/tcg-stub.c F: util/cacheinfo.c F: util/cacheflush.c +F: scripts/coccinelle/cpu_env.cocci F: scripts/decodetree.py F: docs/devel/decodetree.rst F: docs/devel/tcg* diff --git a/scripts/coccinelle/cpu_env.cocci b/scripts/coccinelle/cpu_env.cocci new file mode 100644 index 0000000000..5a70c2211a --- /dev/null +++ b/scripts/coccinelle/cpu_env.cocci @@ -0,0 +1,100 @@ +/* + * Convert &ARCH_CPU(..)->env to use cpu_env(..). + * + * Rationale: ARCH_CPU() might be slow, being a QOM cast macro. + * cpu_env() is its fast equivalent. + * CPU() macro is a no-op. + * + * SPDX-License-Identifier: GPL-2.0-or-later + * SPDX-FileCopyrightText: Linaro Ltd 2024 + * SPDX-FileContributor: Philippe Mathieu-Daudé + */ + +@@ +type ArchCPU =~ "CPU$"; +identifier cpu; +type CPUArchState =~ "^CPU"; +identifier env; +@@ + ArchCPU *cpu; + ... + CPUArchState *env = &cpu->env; + <... +- &cpu->env ++ env + ...> + + +/* + * Due to commit 8ce5c64499 ("semihosting: Return failure from + * softmmu-uaccess.h functions"), skip functions using softmmu-uaccess.h + * macros (they don't pass 'env' as argument). + */ +@ uaccess_api_used exists @ +identifier semihosting_func =~ "^(put|get)_user_[us](al|8|16|32)$"; +@@ + semihosting_func(...) + + +/* + * Argument is CPUState* + */ +@ cpustate_arg depends on !uaccess_api_used @ +identifier cpu; +type ArchCPU =~ "CPU$"; +type CPUArchState; +identifier ARCH_CPU =~ "CPU$"; +identifier env; +CPUState *cs; +@@ +- ArchCPU *cpu = ARCH_CPU(cs); + ... +- CPUArchState *env = &cpu->env; ++ CPUArchState *env = cpu_env(cs); + ... when != cpu + + +/* + * Argument is not CPUState* but a related QOM object. + * CPU() is not a QOM macro but a cast (See commit 0d6d1ab499). + */ +@ depends on !uaccess_api_used && !cpustate_arg @ +identifier cpu; +type ArchCPU =~ "CPU$"; +type CPUArchState; +identifier ARCH_CPU =~ "CPU$"; +identifier env; +expression cs; +@@ +- ArchCPU *cpu = ARCH_CPU(cs); + ... +- CPUArchState *env = &cpu->env; ++ CPUArchState *env = cpu_env(CPU(cs)); + ... when != cpu + + +/* When single use of 'env', call cpu_env() in place */ +@ depends on !uaccess_api_used @ +type CPUArchState; +identifier env; +expression cs; +@@ +- CPUArchState *env = cpu_env(cs); + ... when != env +- env ++ cpu_env(cs) + ... when != env + + +/* Both first_cpu/current_cpu are extern CPUState* */ +@@ +symbol first_cpu; +symbol current_cpu; +@@ +( +- CPU(first_cpu) ++ first_cpu +| +- CPU(current_cpu) ++ current_cpu +)
Add a Coccinelle script to convert the following slow path (due to the QOM cast macro): &ARCH_CPU(..)->env to the following fast path: cpu_env(..) Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> --- MAINTAINERS | 1 + scripts/coccinelle/cpu_env.cocci | 100 +++++++++++++++++++++++++++++++ 2 files changed, 101 insertions(+) create mode 100644 scripts/coccinelle/cpu_env.cocci