diff options
author | jhb <jhb@FreeBSD.org> | 2004-01-28 20:44:08 +0000 |
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committer | jhb <jhb@FreeBSD.org> | 2004-01-28 20:44:08 +0000 |
commit | 657a196e7a050d9d36fa60573c770822bdffdd5a (patch) | |
tree | 2c0d2a9ee57dcbe1354ee965e75ed09a0646aa35 /sys/i386 | |
parent | 7c38a96e26ea6ac5011842d1d51cd51ed70eb958 (diff) | |
download | FreeBSD-src-657a196e7a050d9d36fa60573c770822bdffdd5a.zip FreeBSD-src-657a196e7a050d9d36fa60573c770822bdffdd5a.tar.gz |
Optimize the i386 interrupt entry code to not reload the segment registers
if they already contain the correct kernel selectors.
Reviewed by: peter
Suggested by: peter
Diffstat (limited to 'sys/i386')
-rw-r--r-- | sys/i386/i386/apic_vector.s | 69 | ||||
-rw-r--r-- | sys/i386/isa/atpic_vector.s | 5 |
2 files changed, 34 insertions, 40 deletions
diff --git a/sys/i386/i386/apic_vector.s b/sys/i386/i386/apic_vector.s index 871fd79..ad7038c 100644 --- a/sys/i386/i386/apic_vector.s +++ b/sys/i386/i386/apic_vector.s @@ -57,6 +57,18 @@ pushl %es ; \ pushl %fs +#define PUSH_FRAME_AND_SET_SEGS \ + PUSH_FRAME ; \ + mov %fs,%ax ; /* get current per-cpu selector */ \ + cmp $KPSEL,%ax ; /* are we already in the kernel? */ \ + je 1f ; /* skip expensive segment reloads */ \ + mov $KDSEL,%ax ; /* load kernel ds, es and fs */ \ + mov %ax,%ds ; \ + mov %ax,%es ; \ + mov $KPSEL,%ax ; \ + mov %ax,%fs ; \ +1: + #define POP_FRAME \ popl %fs ; \ popl %es ; \ @@ -75,12 +87,7 @@ .text ; \ SUPERALIGN_TEXT ; \ IDTVEC(vec_name) ; \ - PUSH_FRAME ; \ - movl $KDSEL, %eax ; /* reload with kernel's data segment */ \ - mov %ax, %ds ; \ - mov %ax, %es ; \ - movl $KPSEL, %eax ; /* reload with per-CPU data segment */ \ - mov %ax, %fs ; \ + PUSH_FRAME_AND_SET_SEGS ; \ FAKE_MCOUNT(13*4(%esp)) ; \ movl lapic, %edx ; /* pointer to local APIC */ \ movl LA_ISR + 16 * (index)(%edx), %eax ; /* load ISR */ \ @@ -130,9 +137,12 @@ MCOUNT_LABEL(eintr2) IDTVEC(invltlb) pushl %eax pushl %ds + mov %ds,%ax /* get current data selector */ + cmp $KDSEL,%ax /* are we already in the kernel? */ + je 1f /* skip expensive segment reload */ movl $KDSEL, %eax /* Kernel data selector */ mov %ax, %ds - +1: #ifdef COUNT_XINVLTLB_HITS pushl %fs movl $KPSEL, %eax /* Private space selector */ @@ -163,9 +173,12 @@ IDTVEC(invltlb) IDTVEC(invlpg) pushl %eax pushl %ds + mov %ds,%ax /* get current data selector */ + cmp $KDSEL,%ax /* are we already in the kernel? */ + je 1f /* skip expensive segment reload */ movl $KDSEL, %eax /* Kernel data selector */ mov %ax, %ds - +1: #ifdef COUNT_XINVLTLB_HITS pushl %fs movl $KPSEL, %eax /* Private space selector */ @@ -197,9 +210,12 @@ IDTVEC(invlrng) pushl %eax pushl %edx pushl %ds + mov %ds,%ax /* get current data selector */ + cmp $KDSEL,%ax /* are we already in the kernel? */ + je 1f /* skip expensive segment reload */ movl $KDSEL, %eax /* Kernel data selector */ mov %ax, %ds - +1: #ifdef COUNT_XINVLTLB_HITS pushl %fs movl $KPSEL, %eax /* Private space selector */ @@ -234,12 +250,7 @@ IDTVEC(invlrng) .text SUPERALIGN_TEXT IDTVEC(hardclock) - PUSH_FRAME - movl $KDSEL, %eax /* reload with kernel's data segment */ - mov %ax, %ds - mov %ax, %es - movl $KPSEL, %eax - mov %ax, %fs + PUSH_FRAME_AND_SET_SEGS movl lapic, %edx movl $0, LA_EOI(%edx) /* End Of Interrupt to APIC */ @@ -257,12 +268,7 @@ IDTVEC(hardclock) .text SUPERALIGN_TEXT IDTVEC(statclock) - PUSH_FRAME - movl $KDSEL, %eax /* reload with kernel's data segment */ - mov %ax, %ds - mov %ax, %es - movl $KPSEL, %eax - mov %ax, %fs + PUSH_FRAME_AND_SET_SEGS movl lapic, %edx movl $0, LA_EOI(%edx) /* End Of Interrupt to APIC */ @@ -286,12 +292,7 @@ IDTVEC(statclock) .text SUPERALIGN_TEXT IDTVEC(cpuast) - PUSH_FRAME - movl $KDSEL, %eax - mov %ax, %ds /* use KERNEL data segment */ - mov %ax, %es - movl $KPSEL, %eax - mov %ax, %fs + PUSH_FRAME_AND_SET_SEGS movl lapic, %edx movl $0, LA_EOI(%edx) /* End Of Interrupt to APIC */ @@ -377,12 +378,7 @@ IDTVEC(cpustop) .text SUPERALIGN_TEXT IDTVEC(rendezvous) - PUSH_FRAME - movl $KDSEL, %eax - mov %ax, %ds /* use KERNEL data segment */ - mov %ax, %es - movl $KPSEL, %eax - mov %ax, %fs + PUSH_FRAME_AND_SET_SEGS call smp_rendezvous_action @@ -397,12 +393,7 @@ IDTVEC(rendezvous) */ SUPERALIGN_TEXT IDTVEC(lazypmap) - PUSH_FRAME - movl $KDSEL, %eax - mov %ax, %ds /* use KERNEL data segment */ - mov %ax, %es - movl $KPSEL, %eax - mov %ax, %fs + PUSH_FRAME_AND_SET_SEGS call pmap_lazyfix_action diff --git a/sys/i386/isa/atpic_vector.s b/sys/i386/isa/atpic_vector.s index e3dc38f..4b819ce 100644 --- a/sys/i386/isa/atpic_vector.s +++ b/sys/i386/isa/atpic_vector.s @@ -63,12 +63,15 @@ IDTVEC(vec_name) ; \ pushl %ds ; /* save data and extra segments ... */ \ pushl %es ; \ pushl %fs ; \ + mov %fs,%ax ; /* get current per-cpu selector */ \ + cmp $KPSEL,%ax ; /* are we already in the kernel? */ \ + je 1f ; /* skip expensive segment reloads */ \ mov $KDSEL,%ax ; /* load kernel ds, es and fs */ \ mov %ax,%ds ; \ mov %ax,%es ; \ mov $KPSEL,%ax ; \ mov %ax,%fs ; \ -; \ +1: ; \ FAKE_MCOUNT(13*4(%esp)) ; /* XXX late to avoid double count */ \ pushl $irq_num; /* pass the IRQ */ \ call atpic_handle_intr ; \ |