linux/arch/x86/events/probe.c
Xin Li (Intel) efef7f184f x86/msr: Add explicit includes of <asm/msr.h>
For historic reasons there are some TSC-related functions in the
<asm/msr.h> header, even though there's an <asm/tsc.h> header.

To facilitate the relocation of rdtsc{,_ordered}() from <asm/msr.h>
to <asm/tsc.h> and to eventually eliminate the inclusion of
<asm/msr.h> in <asm/tsc.h>, add an explicit <asm/msr.h> dependency
to the source files that reference definitions from <asm/msr.h>.

[ mingo: Clarified the changelog. ]

Signed-off-by: Xin Li (Intel) <xin@zytor.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Uros Bizjak <ubizjak@gmail.com>
Link: https://lore.kernel.org/r/20250501054241.1245648-1-xin@zytor.com
2025-05-02 10:23:47 +02:00

65 lines
1.3 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/export.h>
#include <linux/types.h>
#include <linux/bits.h>
#include <asm/msr.h>
#include "probe.h"
static umode_t
not_visible(struct kobject *kobj, struct attribute *attr, int i)
{
return 0;
}
/*
* Accepts msr[] array with non populated entries as long as either
* msr[i].msr is 0 or msr[i].grp is NULL. Note that the default sysfs
* visibility is visible when group->is_visible callback is set.
*/
unsigned long
perf_msr_probe(struct perf_msr *msr, int cnt, bool zero, void *data)
{
unsigned long avail = 0;
unsigned int bit;
u64 val;
if (cnt >= BITS_PER_LONG)
return 0;
for (bit = 0; bit < cnt; bit++) {
if (!msr[bit].no_check) {
struct attribute_group *grp = msr[bit].grp;
u64 mask;
/* skip entry with no group */
if (!grp)
continue;
grp->is_visible = not_visible;
/* skip unpopulated entry */
if (!msr[bit].msr)
continue;
if (msr[bit].test && !msr[bit].test(bit, data))
continue;
/* Virt sucks; you cannot tell if a R/O MSR is present :/ */
if (rdmsrq_safe(msr[bit].msr, &val))
continue;
mask = msr[bit].mask;
if (!mask)
mask = ~0ULL;
/* Disable zero counters if requested. */
if (!zero && !(val & mask))
continue;
grp->is_visible = NULL;
}
avail |= BIT(bit);
}
return avail;
}
EXPORT_SYMBOL_GPL(perf_msr_probe);