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Peter Anvin" , "linux-toolchains@vger.kernel.org" Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-toolchains@vger.kernel.org On Tue, Mar 7, 2023 at 1:11=E2=80=AFPM Luck, Tony wro= te: > > > (a) it shouldn't define and declare a static function in a header file > > > > (b) the resctrl_sched_in() inline function is midesigned to begin with > > Fixing "b" would seem to be to just pass "next_p" to the function to > use instead of "current". ``` diff --git a/arch/x86/include/asm/resctrl.h b/arch/x86/include/asm/resctrl.= h index 52788f79786f..f46c0b97334d 100644 --- a/arch/x86/include/asm/resctrl.h +++ b/arch/x86/include/asm/resctrl.h @@ -49,7 +49,7 @@ DECLARE_STATIC_KEY_FALSE(rdt_mon_enable_key); * simple as possible. * Must be called with preemption disabled. */ -static void __resctrl_sched_in(void) +static void __resctrl_sched_in(struct task_struct *next) { struct resctrl_pqr_state *state =3D this_cpu_ptr(&pqr_state); u32 closid =3D state->default_closid; @@ -61,13 +61,13 @@ static void __resctrl_sched_in(void) * Else use the closid/rmid assigned to this cpu. */ if (static_branch_likely(&rdt_alloc_enable_key)) { - tmp =3D READ_ONCE(current->closid); + tmp =3D READ_ONCE(next->closid); if (tmp) closid =3D tmp; } if (static_branch_likely(&rdt_mon_enable_key)) { - tmp =3D READ_ONCE(current->rmid); + tmp =3D READ_ONCE(next->rmid); if (tmp) rmid =3D tmp; } @@ -88,17 +88,17 @@ static inline unsigned int resctrl_arch_round_mon_val(unsigned int val) return val * scale; } -static inline void resctrl_sched_in(void) +static inline void resctrl_sched_in(struct task_struct *next) { if (static_branch_likely(&rdt_enable_key)) - __resctrl_sched_in(); + __resctrl_sched_in(next); } void resctrl_cpu_detect(struct cpuinfo_x86 *c); #else -static inline void resctrl_sched_in(void) {} +static inline void resctrl_sched_in(struct task_struct *next) {} static inline void resctrl_cpu_detect(struct cpuinfo_x86 *c) {} #endif /* CONFIG_X86_CPU_RESCTRL */ diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c index e2c1599d1b37..d970347838a4 100644 --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c @@ -314,7 +314,7 @@ static void update_cpu_closid_rmid(void *info) * executing task might have its own closid selected. Just reuse * the context switch code. */ - resctrl_sched_in(); + resctrl_sched_in(current); } /* @@ -530,7 +530,7 @@ static void _update_task_closid_rmid(void *task) * Otherwise, the MSR is updated when the task is scheduled in. */ if (task =3D=3D current) - resctrl_sched_in(); + resctrl_sched_in(current); } static void update_task_closid_rmid(struct task_struct *t) diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index 470c128759ea..708c87b88cc1 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -212,7 +212,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) switch_fpu_finish(); /* Load the Intel cache allocation PQR MSR. */ - resctrl_sched_in(); + resctrl_sched_in(next_p); return prev_p; } diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 4e34b3b68ebd..bb65a68b4b49 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -656,7 +656,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) } /* Load the Intel cache allocation PQR MSR. */ - resctrl_sched_in(); + resctrl_sched_in(next_p); return prev_p; } ``` ? > > Can you expand about part "a" ... Linux has zillions of static inline fun= ctions > in header files to handle CONFIG options. One version is the real McCoy > while the other is just a stub for the CONFIG=3Dn case. Right, I had the same question. Perhaps it's more so that no one calls __resctrl_sched_in, only resctrl_sched_in, therefor they should be folded into one function? > > What's different about this one? > > -Tony --=20 Thanks, ~Nick Desaulniers