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9261e050b6
We've had ->read_tsc() and ->read_tscp() paravirt hooks since the very beginning of paravirt, i.e.,d3561b7fa0("[PATCH] paravirt: header and stubs for paravirtualisation"). AFAICT, the only paravirt guest implementation that ever replaced these calls was vmware, and it's gone. Arguably even vmware shouldn't have hooked RDTSC -- we fully support systems that don't have a TSC at all, so there's no point for a paravirt implementation to pretend that we have a TSC but to replace it. I also doubt that these hooks actually worked. Calls to rdtscl() and rdtscll(), which respected the hooks, were used seemingly interchangeably with native_read_tsc(), which did not. Just remove them. If anyone ever needs them again, they can try to make a case for why they need them. Before, on a paravirt config: text data bss dec hex filename 12618257 1816384109363215528273 ecf151 vmlinux After: text data bss dec hex filename 12617207 1816384109363215527223 eced37 vmlinux Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Huang Rui <ray.huang@amd.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Len Brown <lenb@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kvm ML <kvm@vger.kernel.org> Cc: virtualization@lists.linux-foundation.org Link: http://lkml.kernel.org/r/d08a2600fb298af163681e5efd8e599d889a5b97.1434501121.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
73 lines
2.1 KiB
C
73 lines
2.1 KiB
C
#include <asm/paravirt.h>
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DEF_NATIVE(pv_irq_ops, irq_disable, "cli");
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DEF_NATIVE(pv_irq_ops, irq_enable, "sti");
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DEF_NATIVE(pv_irq_ops, restore_fl, "push %eax; popf");
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DEF_NATIVE(pv_irq_ops, save_fl, "pushf; pop %eax");
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DEF_NATIVE(pv_cpu_ops, iret, "iret");
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DEF_NATIVE(pv_cpu_ops, irq_enable_sysexit, "sti; sysexit");
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DEF_NATIVE(pv_mmu_ops, read_cr2, "mov %cr2, %eax");
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DEF_NATIVE(pv_mmu_ops, write_cr3, "mov %eax, %cr3");
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DEF_NATIVE(pv_mmu_ops, read_cr3, "mov %cr3, %eax");
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DEF_NATIVE(pv_cpu_ops, clts, "clts");
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#if defined(CONFIG_PARAVIRT_SPINLOCKS) && defined(CONFIG_QUEUED_SPINLOCKS)
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DEF_NATIVE(pv_lock_ops, queued_spin_unlock, "movb $0, (%eax)");
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#endif
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unsigned paravirt_patch_ident_32(void *insnbuf, unsigned len)
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{
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/* arg in %eax, return in %eax */
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return 0;
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}
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unsigned paravirt_patch_ident_64(void *insnbuf, unsigned len)
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{
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/* arg in %edx:%eax, return in %edx:%eax */
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return 0;
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}
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extern bool pv_is_native_spin_unlock(void);
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unsigned native_patch(u8 type, u16 clobbers, void *ibuf,
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unsigned long addr, unsigned len)
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{
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const unsigned char *start, *end;
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unsigned ret;
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#define PATCH_SITE(ops, x) \
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case PARAVIRT_PATCH(ops.x): \
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start = start_##ops##_##x; \
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end = end_##ops##_##x; \
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goto patch_site
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switch (type) {
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PATCH_SITE(pv_irq_ops, irq_disable);
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PATCH_SITE(pv_irq_ops, irq_enable);
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PATCH_SITE(pv_irq_ops, restore_fl);
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PATCH_SITE(pv_irq_ops, save_fl);
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PATCH_SITE(pv_cpu_ops, iret);
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PATCH_SITE(pv_cpu_ops, irq_enable_sysexit);
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PATCH_SITE(pv_mmu_ops, read_cr2);
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PATCH_SITE(pv_mmu_ops, read_cr3);
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PATCH_SITE(pv_mmu_ops, write_cr3);
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PATCH_SITE(pv_cpu_ops, clts);
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#if defined(CONFIG_PARAVIRT_SPINLOCKS) && defined(CONFIG_QUEUED_SPINLOCKS)
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case PARAVIRT_PATCH(pv_lock_ops.queued_spin_unlock):
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if (pv_is_native_spin_unlock()) {
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start = start_pv_lock_ops_queued_spin_unlock;
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end = end_pv_lock_ops_queued_spin_unlock;
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goto patch_site;
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}
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#endif
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default:
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ret = paravirt_patch_default(type, clobbers, ibuf, addr, len);
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break;
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patch_site:
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ret = paravirt_patch_insns(ibuf, len, start, end);
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break;
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}
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#undef PATCH_SITE
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return ret;
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}
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